[PATCH 0/5] ALSA: usb-audio: Audient iD14 MkI vendor controls

[PATCH 0/5] ALSA: usb-audio: Audient iD14 MkI vendor controls

[Will Porter]

The Audient iD14 MkI (2708:0002) keeps its monitor section, output
routing, mixer and input options on vendor extension units. It also
uses feature units whose descriptors declare no controls. On Linux a
user cannot change the routing. The device powers up with every output
on DAW Thru, which bypasses the volume knob.

This series adds those controls in a new mixer_audient_id.c, one group
per patch. A MkI-only name map hides the generic controls that each
group replaces. The MkII keeps audient_id14_map.

Scope: only the iD14 MkI is supported, and only its USB ID reaches the
new code. Other Audient iD models keep the generic driver. Their units
may differ, and this series does not cover them. The file follows
mixer_scarlett2.c, which began with one model and added others through
per-model tables. Names with id14_ hold the MkI's unit IDs and tables. A
later iD model can add its own tables to this file.

sound for-next also has mixer_evo.c for the Audient EVO 4 (2708:0006).
EVO and iD are separate Audient product lines. The iD14 MkI uses other
units and a larger control set: a monitor controller, output routing, a
14 x 4 mixer and write-only controls. So this series keeps the iD line
in its own file.

At probe the driver writes only controls that it cannot read back: the
write-only controls (patch 4) and FU 12 (patch 5). They get the launch
values of Audient's iD application. If a probe write fails, the control
shows the fallback value that those patches describe. The driver does
not write the routing or the mix. User space (alsactl, an application)
sets the rest of the iD application's launch state.

There is no resume code. Every write to a write-only control reaches
the device, so alsactl restore also repairs a device that was reset.
The state across a suspend depends on the power source:
- On USB bus power, a system suspend re-enumerates the device.
- With its mains adapter connected, the device keeps its state across a
  system suspend. This is also true when the host controller resets the
  device and the card stays. The sampled readable controls did not
  change.
- A runtime suspend left the readable controls unchanged on both power
  sources, with no reset logged. A runtime suspend is possible only
  after usbhid releases the HID interface.

Patch 5 replaces the generic "Monitor Mix Playback Volume" (FU 12) with
one of the same name, count and range. FU 12 GET CUR returns stale data
from other units. Its Main L channel ignores writes, but Main R applies
them. audient_id14_map already notes this asymmetry. The new control
holds Main at 0 dB. This is a deliberate change for existing users: a
Main R attenuation set through the generic control no longer applies.

The protocol comes from Audient's iD application (version 4.4.5 for
macOS). USB captures of the application confirmed it.

Test setup:
- iD14 MkI, firmware 1.1.1
- Bazzite 44, kernel 7.2.9-ogc3.1.fc44
- snd-usb-audio built out of tree from the v7.2.9 sound/usb sources
  with this series applied

Tests:
- listening tests: routing, dim, talkback, Cue
- a loopback cable: gain boost, polarity, FU 12 per channel
- alsactl store and restore across a replug
- an out-of-list routing value
- a runtime suspend
- three system suspends (S3) with control reads running at about 3000
  per second: no read failed after a resume
- the optical power-on mode, read on macOS 27.0.1 with no Audient
  software running

The series is based on sound for-next a4ef328ce3b3. Each patch builds
on its own there with make W=1 sound/usb/. The hardware tests used the
complete series on 7.2.9 sources, where snd_usb_mixer_add_list() has no
look_for_empty argument. The series passes true, which keeps that
behaviour.

Will Porter (5):
  ALSA: usb-audio: Give the Audient iD14 MkI its own mixer map
  ALSA: usb-audio: Add Audient iD14 MkI monitor and routing controls
  ALSA: usb-audio: Add Audient iD14 MkI mixer matrix
  ALSA: usb-audio: Add Audient iD14 MkI write-only controls
  ALSA: usb-audio: Replace the Audient iD14 MkI FU 12 control

 sound/usb/Makefile           |   1 +
 sound/usb/mixer_audient_id.c | 790 +++++++++++++++++++++++++++++++++++
 sound/usb/mixer_audient_id.h |   7 +
 sound/usb/mixer_maps.c       |  10 +-
 sound/usb/mixer_quirks.c     |   4 +
 5 files changed, 811 insertions(+), 1 deletion(-)
 create mode 100644 sound/usb/mixer_audient_id.c
 create mode 100644 sound/usb/mixer_audient_id.h


base-commit: a4ef328ce3b3ab1bf63c6350e890f13b9b25e3f1
-- 
2.47.3

[PATCH 1/5] ALSA: usb-audio: Give the Audient iD14 MkI its own mixer map

[Will Porter]

The iD14 MkI (2708:0002) and MkII (2708:0008) share audient_id14_map.
Later commits add MkI vendor controls that replace some of the generic
MkI controls. The MkII keeps the generic controls. Give the MkI its own
copy of the map.

No functional change.

Assisted-by: Claude:claude-opus-5-5
Signed-off-by: Will Porter <mrwillporter@gmail.com>
---
 sound/usb/mixer_maps.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/sound/usb/mixer_maps.c b/sound/usb/mixer_maps.c
index 98b414621..7795a5fbe 100644
--- a/sound/usb/mixer_maps.c
+++ b/sound/usb/mixer_maps.c
@@ -526,6 +526,12 @@ static const struct usbmix_name_map audient_id14_map[] = {
 	{}
 };
 
+/* Audient iD14 MkI: model-specific control map. */
+static const struct usbmix_name_map audient_id14_mk1_map[] = {
+	{ 12, "Monitor Mix Playback" },	/* FU, partial coverage */
+	{}
+};
+
 /*
  * Audient iD24: feature unit 12 ("Speaker Playback Volume") sits in the
  * monitor-mixer branch and does not apply volume to all of its channels;
@@ -638,7 +644,7 @@ static const struct usbmix_ctl_map usbmix_ctl_maps[] = {
 	{
 		/* Audient iD14 MkI */
 		.id = USB_ID(0x2708, 0x0002),
-		.map = audient_id14_map,
+		.map = audient_id14_mk1_map,
 	},
 	{
 		/* Audient EVO4 MkI */
-- 
2.47.3

[PATCH 2/5] ALSA: usb-audio: Add Audient iD14 MkI monitor and routing controls

[Will Porter]

The iD14 MkI keeps three groups of controls where the generic driver
cannot discover them:
- the monitor controller, on Audient extension unit 54
- the headphone level, on feature unit 10, whose descriptor declares
  no controls
- the output routing, on extension unit 51

So Linux users cannot change the routing. The MkI powers up with every
output on DAW Thru: the USB stream goes straight to the output and
bypasses the volume knob.

Add mixer_audient_id.c with these controls:

- Monitor Speaker Playback Volume and Switch (speaker level and cut)
- Monitor Dim Playback Switch, Monitor Dim Level Playback Volume
- Monitor Mono Playback Switch, Monitor Mono Mode Playback Enum
- Monitor Polarity Invert Playback Switch
- Monitor Headphone Playback Volume and Switch (FU 10, channels 3-4)
- Talkback Playback Switch
- Main Out L/R Source Playback Enum, Headphone L/R Source Playback Enum:
  "Main Mix", "Cue Mix" or "DAW Thru (full scale)"

Every get reads the device, because the volume knob changes the speaker
and headphone levels. The volumes are 0-128 in 1 dB steps: 0 is -128 dB
(mute) and 128 is 0 dB. The driver converts them to the device's s16 in
1/256 dB.

The routing controls are mono enums, as in mixer_scarlett2.c. Thus one
output on DAW Thru cannot hide behind its pair. The "... Playback Enum"
names follow the same driver. A source outside the list reads as an
extra item, "Other". A put rejects "Other", but alsactl store saves it.
A restore of it then fails for that control only, or for the card with
--pedantic. The restore cannot recreate the original source. So after a
replug on bus power, that output stays on its power-on source, DAW Thru.

The file is named for the iD family and keeps model data in per-model
tables, as mixer_scarlett2.c does. Only the iD14 MkI is supported. Other
iD models keep the generic driver.

The driver writes nothing at probe. User space sets the launch state of
Audient's iD application (all outputs on Main Mix).

Test setup:
- iD14 MkI, firmware 1.1.1
- Bazzite 44, kernel 7.2.9-ogc3.1.fc44
- snd-usb-audio built out of tree from the v7.2.9 sound/usb sources
  and the complete driver (this commit and the later ones)

Results:
- routing: listening tests (Main Mix and Cue Mix, left and right) and
  read-back
- dim, by ear: host switch and iD key
- talkback, by ear (a later commit adds the talkback source control)
- alsactl store and restore across a replug
- an out-of-list routing byte (0x13) reads as "Other"

Assisted-by: Claude:claude-opus-5-5
Signed-off-by: Will Porter <mrwillporter@gmail.com>
---
 sound/usb/Makefile           |   1 +
 sound/usb/mixer_audient_id.c | 407 +++++++++++++++++++++++++++++++++++
 sound/usb/mixer_audient_id.h |   7 +
 sound/usb/mixer_quirks.c     |   4 +
 4 files changed, 419 insertions(+)
 create mode 100644 sound/usb/mixer_audient_id.c
 create mode 100644 sound/usb/mixer_audient_id.h

diff --git a/sound/usb/Makefile b/sound/usb/Makefile
index 2e842dcc7..7e4e6553d 100644
--- a/sound/usb/Makefile
+++ b/sound/usb/Makefile
@@ -11,6 +11,7 @@ snd-usb-audio-y := 	card.o \
 			helper.o \
 			implicit.o \
 			mixer.o \
+			mixer_audient_id.o \
 			mixer_evo.o \
 			mixer_quirks.o \
 			mixer_scarlett.o \
diff --git a/sound/usb/mixer_audient_id.c b/sound/usb/mixer_audient_id.c
new file mode 100644
index 000000000..b4d1e1697
--- /dev/null
+++ b/sound/usb/mixer_audient_id.c
@@ -0,0 +1,407 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Audient iD mixer controls
+ *
+ * Supported models:
+ * - iD14 MkI (2708:0002)
+ *
+ * Other Audient iD models keep the generic driver. Their units may differ,
+ * and this code does not cover them. As in mixer_scarlett2.c, a later
+ * model can add its own control tables to this file. Unit IDs, tables and
+ * functions named id14_* are for the iD14 MkI only. The id_* helpers take
+ * a table.
+ *
+ * The iD14 MkI (2708:0002) has its monitor controller, output routing,
+ * headphone level, input options and a 14 x 4 mixer on Audient extension
+ * units and on feature units whose descriptors declare no controls. The
+ * generic driver cannot discover these. This file adds them.
+ *
+ * The protocol comes from Audient's iD application (version 4.4.5 for
+ * macOS). USB captures of the application confirmed it.
+ *
+ * The controls read the device on every get: the front panel changes
+ * several of them.
+ *
+ * Get and put need no lock of their own: the control core runs put with
+ * card->controls_rwsem held for writing and get with it held for reading.
+ */
+
+#include <linux/slab.h>
+#include <linux/unaligned.h>
+#include <linux/usb.h>
+#include <linux/usb/audio.h>
+#include <linux/usb/audio-v2.h>
+#include <sound/control.h>
+#include <sound/tlv.h>
+
+#include "usbaudio.h"
+#include "mixer.h"
+#include "helper.h"
+#include "mixer_audient_id.h"
+
+/* Unit IDs */
+#define ID14_FU_OUT		0x0a	/* feature unit before the outputs */
+#define ID14_ROUTE		0x33	/* routing XU: CN = destination */
+#define ID14_MON		0x36	/* monitor controller XU */
+
+/* Control selectors */
+#define ID14_ROUTE_SOURCE	0x06	/* u8: source of the destination */
+#define ID14_MON_MONO		0x00
+#define ID14_MON_MONO_MODE	0x01
+#define ID14_MON_POLARITY	0x03
+#define ID14_MON_CUT		0x04
+#define ID14_MON_DIM		0x05
+#define ID14_MON_DIM_LEVEL	0x06	/* s16, 1/256 dB */
+#define ID14_MON_TALKBACK	0x07
+#define ID14_MON_VOLUME		0x12	/* s16, 1/256 dB; the knob also sets it */
+
+/*
+ * Volumes are the device's s16 in 1/256 dB; the knob and the iD application
+ * use 1 dB steps. The controls show the steps: 0 (-128 dB, mute) ... 128 (0 dB).
+ */
+#define ID_DB(db)		((db) * 256)
+#define ID_VOL_MAX		128		/* control value for 0 dB */
+
+enum id_kind {
+	ID_BOOL,	/* u8: 1 = on */
+	ID_BOOL_INV,	/* u8: 1 = cut or mute, shown as a switch that is off */
+	ID_VOL,		/* s16 in 1/256 dB; control value 0 ... ID_VOL_MAX, 1 dB steps */
+	ID_ENUM,	/* item list with device values (struct id_enum) */
+};
+
+struct id_enum {
+	const char *const *texts;
+	const u32 *values;
+	unsigned int items;
+	u8 len;		/* bytes on the wire */
+};
+
+struct id_ctl {
+	const char *name;
+	enum id_kind kind;
+	u8 unit;
+	u8 cs;
+	u8 cn;		/* first channel number */
+	u8 channels;
+	const struct id_enum *e;
+};
+
+/*
+ * The texts have one item more than the values. A put cannot select the last
+ * item, "Other": it shows a device value outside the list.
+ */
+#define ID_ENUM_TEXTS(name, texts_, len_, ...)					\
+	static const u32 name##_values[] = { __VA_ARGS__ };			\
+	static const struct id_enum name = {					\
+		.texts = texts_, .values = name##_values,			\
+		.items = ARRAY_SIZE(name##_values), .len = len_,		\
+	}
+#define ID_ENUM_DEF(name, len_, ...)						\
+	ID_ENUM_TEXTS(name, name##_texts, len_, __VA_ARGS__);			\
+	static_assert(ARRAY_SIZE(name##_texts) == ARRAY_SIZE(name##_values) + 1)
+
+/* Mono mode: one-speaker sum (Left, Right) or phantom centre. */
+static const char *const id14_mono_mode_texts[] = { "Left", "Centre", "Right", "Other" };
+
+ID_ENUM_DEF(id14_mono_mode, 1, 1, 0, 2);
+
+/*
+ * Routing sources for each destination. DAW Thru plays the USB stream
+ * directly and bypasses the volume knob: full scale. Main Mix is 0x14/0x15
+ * on the main outputs and 0x18/0x19 on the headphones.
+ */
+static const char *const id14_route_texts[] = {
+	"Main Mix", "Cue Mix", "DAW Thru (full scale)", "Other",
+};
+
+ID_ENUM_TEXTS(id14_route_ml, id14_route_texts, 1, 0x14, 0x10, 0x00);
+ID_ENUM_TEXTS(id14_route_mr, id14_route_texts, 1, 0x15, 0x11, 0x01);
+ID_ENUM_TEXTS(id14_route_hl, id14_route_texts, 1, 0x18, 0x10, 0x02);
+ID_ENUM_TEXTS(id14_route_hr, id14_route_texts, 1, 0x19, 0x11, 0x03);
+static_assert(ARRAY_SIZE(id14_route_texts) == ARRAY_SIZE(id14_route_ml_values) + 1);
+
+static const struct id_ctl id14_mk1_ctls[] = {
+	{ .name = "Monitor Speaker Playback Volume", .kind = ID_VOL, .unit = ID14_MON,
+	  .cs = ID14_MON_VOLUME, .channels = 1 },
+	{ .name = "Monitor Speaker Playback Switch", .kind = ID_BOOL_INV, .unit = ID14_MON,
+	  .cs = ID14_MON_CUT, .channels = 1 },
+	{ .name = "Monitor Dim Playback Switch", .kind = ID_BOOL, .unit = ID14_MON,
+	  .cs = ID14_MON_DIM, .channels = 1 },
+	{ .name = "Monitor Dim Level Playback Volume", .kind = ID_VOL, .unit = ID14_MON,
+	  .cs = ID14_MON_DIM_LEVEL, .channels = 1 },
+	{ .name = "Monitor Mono Playback Switch", .kind = ID_BOOL, .unit = ID14_MON,
+	  .cs = ID14_MON_MONO, .channels = 1 },
+	{ .name = "Monitor Mono Mode Playback Enum", .kind = ID_ENUM, .unit = ID14_MON,
+	  .cs = ID14_MON_MONO_MODE, .channels = 1, .e = &id14_mono_mode },
+	{ .name = "Monitor Polarity Invert Playback Switch", .kind = ID_BOOL, .unit = ID14_MON,
+	  .cs = ID14_MON_POLARITY, .channels = 1 },
+	/* The descriptor declares no controls on FU 10; the headphones are CN 3-4. */
+	{ .name = "Monitor Headphone Playback Volume", .kind = ID_VOL, .unit = ID14_FU_OUT,
+	  .cs = UAC_FU_VOLUME, .cn = 3, .channels = 2 },
+	{ .name = "Monitor Headphone Playback Switch", .kind = ID_BOOL_INV, .unit = ID14_FU_OUT,
+	  .cs = UAC_FU_MUTE, .cn = 3, .channels = 2 },
+	{ .name = "Talkback Playback Switch", .kind = ID_BOOL, .unit = ID14_MON,
+	  .cs = ID14_MON_TALKBACK, .channels = 1 },
+	{ .name = "Main Out L Source Playback Enum", .kind = ID_ENUM, .unit = ID14_ROUTE,
+	  .cs = ID14_ROUTE_SOURCE, .cn = 0, .channels = 1, .e = &id14_route_ml },
+	{ .name = "Main Out R Source Playback Enum", .kind = ID_ENUM, .unit = ID14_ROUTE,
+	  .cs = ID14_ROUTE_SOURCE, .cn = 1, .channels = 1, .e = &id14_route_mr },
+	{ .name = "Headphone L Source Playback Enum", .kind = ID_ENUM, .unit = ID14_ROUTE,
+	  .cs = ID14_ROUTE_SOURCE, .cn = 2, .channels = 1, .e = &id14_route_hl },
+	{ .name = "Headphone R Source Playback Enum", .kind = ID_ENUM, .unit = ID14_ROUTE,
+	  .cs = ID14_ROUTE_SOURCE, .cn = 3, .channels = 1, .e = &id14_route_hr },
+	{ }
+};
+
+/* Per-control state; the usb_mixer_elem_list must come first (snd_usb_mixer_elem_free). */
+struct id_elem {
+	struct usb_mixer_elem_list list;
+	const struct id_ctl *ctl;
+};
+
+/* 0 = -128 dB (mute), 1 dB per step: ID_VOL_MAX = 0 dB. */
+static const DECLARE_TLV_DB_SCALE(id_vol_tlv, -12800, 100, 1);
+
+static int id_xfer(struct usb_mixer_interface *mixer, bool set,
+		   u8 unit, u8 cs, u8 cn, void *buf, int len)
+{
+	struct snd_usb_audio *chip = mixer->chip;
+	struct usb_device *dev = chip->dev;
+	int err;
+
+	CLASS(snd_usb_lock, pm)(chip);
+	if (pm.err < 0)
+		return pm.err;
+	err = snd_usb_ctl_msg(dev,
+			      set ? usb_sndctrlpipe(dev, 0) : usb_rcvctrlpipe(dev, 0),
+			      UAC2_CS_CUR,
+			      USB_TYPE_CLASS | USB_RECIP_INTERFACE |
+			      (set ? USB_DIR_OUT : USB_DIR_IN),
+			      cs << 8 | cn, unit << 8 | mixer->hostif->desc.bInterfaceNumber,
+			      buf, len);
+	if (err < 0)
+		return err;
+	return err == len ? 0 : -EIO;	/* a short transfer is not a value */
+}
+
+static int id_len(const struct id_ctl *c)
+{
+	switch (c->kind) {
+	case ID_ENUM:
+		return c->e->len;
+	case ID_VOL:
+		return 2;
+	default:
+		return 1;
+	}
+}
+
+static bool id_valid(const struct id_ctl *c, long val)
+{
+	switch (c->kind) {
+	case ID_BOOL:
+	case ID_BOOL_INV:
+		return val == 0 || val == 1;
+	case ID_VOL:
+		return val >= 0 && val <= ID_VOL_MAX;
+	case ID_ENUM:
+		return val >= 0 && val < c->e->items;	/* never "Other" */
+	}
+	return false;
+}
+
+/* Read channel i. An item outside the list reads as the extra last item. */
+static int id_read(struct usb_mixer_interface *mixer, const struct id_ctl *c,
+		   unsigned int i, long *val)
+{
+	u8 buf[4] = { 0 };
+	unsigned int item;
+	s16 raw;
+	u32 dev;
+	int err;
+
+	err = id_xfer(mixer, false, c->unit, c->cs, c->cn + i, buf, id_len(c));
+	if (err < 0)
+		return err;
+	raw = get_unaligned_le16(buf);
+
+	switch (c->kind) {
+	case ID_BOOL:
+		*val = !!buf[0];
+		break;
+	case ID_BOOL_INV:
+		*val = !buf[0];
+		break;
+	case ID_VOL:
+		/* the knob moves in whole dB; round anything else to the nearest step */
+		*val = clamp_t(long, DIV_ROUND_CLOSEST(raw, ID_DB(1)) + ID_VOL_MAX,
+			       0, ID_VOL_MAX);
+		break;
+	case ID_ENUM:
+		dev = get_unaligned_le32(buf);
+		for (item = 0; item < c->e->items; item++)
+			if (c->e->values[item] == dev)
+				break;
+		*val = item;	/* c->e->items: "Other" */
+		break;
+	}
+	return 0;
+}
+
+static int id_write(struct usb_mixer_interface *mixer, const struct id_ctl *c,
+		    unsigned int i, long val)
+{
+	u8 buf[4] = { 0 };
+
+	switch (c->kind) {
+	case ID_BOOL:
+		buf[0] = val;
+		break;
+	case ID_BOOL_INV:
+		buf[0] = !val;
+		break;
+	case ID_VOL:
+		put_unaligned_le16(ID_DB(val - ID_VOL_MAX), buf);
+		break;
+	case ID_ENUM:
+		put_unaligned_le32(c->e->values[val], buf);
+		break;
+	}
+	return id_xfer(mixer, true, c->unit, c->cs, c->cn + i, buf, id_len(c));
+}
+
+static int id_info(struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
+{
+	struct id_elem *e = snd_kcontrol_chip(kctl);
+	const struct id_ctl *c = e->ctl;
+
+	switch (c->kind) {
+	case ID_ENUM:
+		return snd_ctl_enum_info(uinfo, c->channels, c->e->items + 1, c->e->texts);
+	case ID_VOL:
+		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+		uinfo->value.integer.min = 0;
+		uinfo->value.integer.max = ID_VOL_MAX;
+		break;
+	default:
+		uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
+		uinfo->value.integer.min = 0;
+		uinfo->value.integer.max = 1;
+		break;
+	}
+	uinfo->count = c->channels;
+	return 0;
+}
+
+static void id_set_value(const struct id_ctl *c, struct snd_ctl_elem_value *v,
+			 unsigned int i, long val)
+{
+	if (c->kind == ID_ENUM)
+		v->value.enumerated.item[i] = val;
+	else
+		v->value.integer.value[i] = val;
+}
+
+static long id_get_value(const struct id_ctl *c, const struct snd_ctl_elem_value *v,
+			 unsigned int i)
+{
+	return c->kind == ID_ENUM ? v->value.enumerated.item[i] : v->value.integer.value[i];
+}
+
+static int id_get(struct snd_kcontrol *kctl, struct snd_ctl_elem_value *v)
+{
+	struct id_elem *e = snd_kcontrol_chip(kctl);
+	const struct id_ctl *c = e->ctl;
+	unsigned int i;
+	long val;
+	int err;
+
+	for (i = 0; i < c->channels; i++) {
+		err = id_read(e->list.mixer, c, i, &val);
+		if (err < 0)
+			return err;
+		id_set_value(c, v, i, val);
+	}
+	return 0;
+}
+
+static int id_put(struct snd_kcontrol *kctl, struct snd_ctl_elem_value *v)
+{
+	struct id_elem *e = snd_kcontrol_chip(kctl);
+	struct usb_mixer_interface *mixer = e->list.mixer;
+	const struct id_ctl *c = e->ctl;
+	unsigned int i;
+	long cur, val;
+	int err, changed = 0;
+
+	for (i = 0; i < c->channels; i++)
+		if (!id_valid(c, id_get_value(c, v, i)))
+			return -EINVAL;
+
+	CLASS(snd_usb_lock, pm)(mixer->chip);
+	if (pm.err < 0)
+		return pm.err;
+
+	for (i = 0; i < c->channels; i++) {
+		val = id_get_value(c, v, i);
+		err = id_read(mixer, c, i, &cur);
+		if (err < 0)
+			return err;
+		if (cur == val)
+			continue;
+		changed = 1;
+		err = id_write(mixer, c, i, val);
+		if (err < 0)
+			return err;
+	}
+	return changed;
+}
+
+static int id_add_ctl(struct usb_mixer_interface *mixer, const struct id_ctl *c)
+{
+	struct snd_kcontrol_new knew = {
+		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+		.name = c->name,
+		/* The front panel changes values: user space must not cache them. */
+		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+		.info = id_info,
+		.get = id_get,
+		.put = id_put,
+	};
+	struct snd_kcontrol *kctl;
+	struct id_elem *e;
+
+	if (c->kind == ID_VOL) {
+		knew.access |= SNDRV_CTL_ELEM_ACCESS_TLV_READ;
+		knew.tlv.p = id_vol_tlv;
+	}
+
+	e = kzalloc_obj(*e);
+	if (!e)
+		return -ENOMEM;
+	e->list.mixer = mixer;
+	e->list.id = c->unit;
+	e->ctl = c;
+
+	kctl = snd_ctl_new1(&knew, e);
+	if (!kctl) {
+		kfree(e);
+		return -ENOMEM;
+	}
+	kctl->private_free = snd_usb_mixer_elem_free;
+	return snd_usb_mixer_add_list(&e->list, kctl, false, true);
+}
+
+/* called from mixer_quirks.c */
+int snd_audient_id14_mk1_controls_create(struct usb_mixer_interface *mixer)
+{
+	const struct id_ctl *c;
+	int err;
+
+	for (c = id14_mk1_ctls; c->name; c++) {
+		err = id_add_ctl(mixer, c);
+		if (err < 0)
+			return err;
+	}
+	return 0;
+}
diff --git a/sound/usb/mixer_audient_id.h b/sound/usb/mixer_audient_id.h
new file mode 100644
index 000000000..c456353ed
--- /dev/null
+++ b/sound/usb/mixer_audient_id.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __USB_MIXER_AUDIENT_ID_H
+#define __USB_MIXER_AUDIENT_ID_H
+
+int snd_audient_id14_mk1_controls_create(struct usb_mixer_interface *mixer);
+
+#endif /* __USB_MIXER_AUDIENT_ID_H */
diff --git a/sound/usb/mixer_quirks.c b/sound/usb/mixer_quirks.c
index 01210cc3f..478e6152c 100644
--- a/sound/usb/mixer_quirks.c
+++ b/sound/usb/mixer_quirks.c
@@ -34,6 +34,7 @@
 #include "usbaudio.h"
 #include "mixer.h"
 #include "mixer_quirks.h"
+#include "mixer_audient_id.h"
 #include "mixer_scarlett.h"
 #include "mixer_scarlett2.h"
 #include "mixer_us16x08.h"
@@ -4609,6 +4610,9 @@ int snd_usb_mixer_apply_create_quirk(struct usb_mixer_interface *mixer)
 	case USB_ID(0x03f0, 0x0269): /* HP TB Dock G2 */
 		err = hp_dock_mixer_create(mixer);
 		break;
+	case USB_ID(0x2708, 0x0002): /* Audient iD14 MkI */
+		err = snd_audient_id14_mk1_controls_create(mixer);
+		break;
 	}
 
 	return err;
-- 
2.47.3

[PATCH 3/5] ALSA: usb-audio: Add Audient iD14 MkI mixer matrix

[Will Porter]

Mixer unit 60 mixes 14 inputs (Mic 1-2, Digi 1-8, DAW 1-4) into four
outputs (Main L/R, Cue L/R). GET RANGE reports -127 to 0 dB in 1 dB
steps, so the generic driver creates four "Analogue 4 Volume" controls
with values from 0 to 127. The crosspoints take -128 dB (mute) to +6 dB
in 1/256 dB steps. The reported range cannot show the gains above 0 dB
or the fine steps that Audient's iD application uses.

Add one control per crosspoint, "Mix <output> <input> Playback Volume".
The value is the device's s16 in 1/256 dB, from -128 dB (mute) to
+6 dB. The fine steps carry the pan law of Audient's iD application.
GET CUR works, so get reads the device. Hide the generic controls in
the MkI map. The driver writes nothing to the mixer at probe.

Test setup:
- iD14 MkI, firmware 1.1.1
- Bazzite 44, kernel 7.2.9-ogc3.1.fc44
- snd-usb-audio built out of tree from the v7.2.9 sound/usb sources
  and the complete driver (this commit and the later ones)

Results:
- crosspoints read back after writes
- DAW 1/2 reach Main L/R and Cue L/R through them (listening test)

Assisted-by: Claude:claude-opus-5-5
Signed-off-by: Will Porter <mrwillporter@gmail.com>
---
 sound/usb/mixer_audient_id.c | 124 +++++++++++++++++++++++++++++++++++
 sound/usb/mixer_maps.c       |   1 +
 2 files changed, 125 insertions(+)

diff --git a/sound/usb/mixer_audient_id.c b/sound/usb/mixer_audient_id.c
index b4d1e1697..5b38590ce 100644
--- a/sound/usb/mixer_audient_id.c
+++ b/sound/usb/mixer_audient_id.c
@@ -43,6 +43,7 @@
 #define ID14_FU_OUT		0x0a	/* feature unit before the outputs */
 #define ID14_ROUTE		0x33	/* routing XU: CN = destination */
 #define ID14_MON		0x36	/* monitor controller XU */
+#define ID14_MIXER		0x3c	/* mixer unit: 14 inputs x 4 outputs */
 
 /* Control selectors */
 #define ID14_ROUTE_SOURCE	0x06	/* u8: source of the destination */
@@ -60,6 +61,7 @@
  * use 1 dB steps. The controls show the steps: 0 (-128 dB, mute) ... 128 (0 dB).
  */
 #define ID_DB(db)		((db) * 256)
+#define ID_DB_MIN		ID_DB(-128)	/* 0x8000: mute */
 #define ID_VOL_MAX		128		/* control value for 0 dB */
 
 enum id_kind {
@@ -392,10 +394,125 @@ static int id_add_ctl(struct usb_mixer_interface *mixer, const struct id_ctl *c)
 	return snd_usb_mixer_add_list(&e->list, kctl, false, true);
 }
 
+/*
+ * iD14 MkI mixer crosspoints: CS 1, CN = input * 4 + output, s16 in
+ * 1/256 dB. The control value is the raw s16, -128 dB (mute) ... +6 dB;
+ * the iD application's pan law needs the fine steps. GET CUR works; no
+ * probe writes.
+ */
+#define ID14_MIX_OUTPUTS	4
+#define ID14_MIX_MAX		ID_DB(6)
+
+static const char *const id14_mix_inputs[] = {
+	"Mic 1", "Mic 2",
+	"Digi 1", "Digi 2", "Digi 3", "Digi 4", "Digi 5", "Digi 6", "Digi 7", "Digi 8",
+	"DAW 1", "DAW 2", "DAW 3", "DAW 4",
+};
+
+static const char *const id14_mix_outputs[ID14_MIX_OUTPUTS] = {
+	"Main L", "Main R", "Cue L", "Cue R",
+};
+
+static const DECLARE_TLV_DB_MINMAX_MUTE(id14_mix_tlv, -12800, 600);
+
+static int id14_mix_info(struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
+{
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+	uinfo->count = 1;
+	uinfo->value.integer.min = ID_DB_MIN;
+	uinfo->value.integer.max = ID14_MIX_MAX;
+	return 0;
+}
+
+struct id14_mix {
+	struct usb_mixer_elem_list list;	/* first: snd_usb_mixer_elem_free */
+	u8 cn;
+};
+
+static int id14_mix_read(struct id14_mix *m, long *val)
+{
+	u8 buf[2];
+	int err;
+
+	err = id_xfer(m->list.mixer, false, ID14_MIXER, UAC2_MU_MIXER, m->cn, buf, sizeof(buf));
+	if (err < 0)
+		return err;
+	*val = clamp_t(long, (s16)get_unaligned_le16(buf), ID_DB_MIN, ID14_MIX_MAX);
+	return 0;
+}
+
+static int id14_mix_get(struct snd_kcontrol *kctl, struct snd_ctl_elem_value *v)
+{
+	struct id14_mix *m = snd_kcontrol_chip(kctl);
+	long val;
+	int err;
+
+	err = id14_mix_read(m, &val);
+	if (err < 0)
+		return err;
+	v->value.integer.value[0] = val;
+	return 0;
+}
+
+static int id14_mix_put(struct snd_kcontrol *kctl, struct snd_ctl_elem_value *v)
+{
+	struct id14_mix *m = snd_kcontrol_chip(kctl);
+	long cur, val = v->value.integer.value[0];
+	u8 buf[2];
+	int err;
+
+	if (val < ID_DB_MIN || val > ID14_MIX_MAX)
+		return -EINVAL;
+	CLASS(snd_usb_lock, pm)(m->list.mixer->chip);
+	if (pm.err < 0)
+		return pm.err;
+	err = id14_mix_read(m, &cur);
+	if (err < 0 || cur == val)
+		return err;
+	put_unaligned_le16(val, buf);
+	err = id_xfer(m->list.mixer, true, ID14_MIXER, UAC2_MU_MIXER, m->cn, buf, sizeof(buf));
+	return err < 0 ? err : 1;
+}
+
+static int id14_mix_add_ctl(struct usb_mixer_interface *mixer, unsigned int in,
+			    unsigned int out)
+{
+	struct snd_kcontrol_new knew = {
+		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
+			  SNDRV_CTL_ELEM_ACCESS_VOLATILE |
+			  SNDRV_CTL_ELEM_ACCESS_TLV_READ,
+		.info = id14_mix_info,
+		.get = id14_mix_get,
+		.put = id14_mix_put,
+		.tlv.p = id14_mix_tlv,
+	};
+	struct snd_kcontrol *kctl;
+	struct id14_mix *m;
+
+	m = kzalloc_obj(*m);
+	if (!m)
+		return -ENOMEM;
+	m->list.mixer = mixer;
+	m->list.id = ID14_MIXER;
+	m->cn = in * ID14_MIX_OUTPUTS + out;
+
+	kctl = snd_ctl_new1(&knew, m);
+	if (!kctl) {
+		kfree(m);
+		return -ENOMEM;
+	}
+	snprintf(kctl->id.name, sizeof(kctl->id.name), "Mix %s %s Playback Volume",
+		 id14_mix_outputs[out], id14_mix_inputs[in]);
+	kctl->private_free = snd_usb_mixer_elem_free;
+	return snd_usb_mixer_add_list(&m->list, kctl, false, true);
+}
+
 /* called from mixer_quirks.c */
 int snd_audient_id14_mk1_controls_create(struct usb_mixer_interface *mixer)
 {
 	const struct id_ctl *c;
+	unsigned int in, out;
 	int err;
 
 	for (c = id14_mk1_ctls; c->name; c++) {
@@ -403,5 +520,12 @@ int snd_audient_id14_mk1_controls_create(struct usb_mixer_interface *mixer)
 		if (err < 0)
 			return err;
 	}
+	for (in = 0; in < ARRAY_SIZE(id14_mix_inputs); in++) {
+		for (out = 0; out < ID14_MIX_OUTPUTS; out++) {
+			err = id14_mix_add_ctl(mixer, in, out);
+			if (err < 0)
+				return err;
+		}
+	}
 	return 0;
 }
diff --git a/sound/usb/mixer_maps.c b/sound/usb/mixer_maps.c
index 7795a5fbe..e147c1a48 100644
--- a/sound/usb/mixer_maps.c
+++ b/sound/usb/mixer_maps.c
@@ -529,6 +529,7 @@ static const struct usbmix_name_map audient_id14_map[] = {
 /* Audient iD14 MkI: model-specific control map. */
 static const struct usbmix_name_map audient_id14_mk1_map[] = {
 	{ 12, "Monitor Mix Playback" },	/* FU, partial coverage */
+	{ 60, NULL },			/* MU, see mixer_audient_id.c */
 	{}
 };
 
-- 
2.47.3

[PATCH 4/5] ALSA: usb-audio: Add Audient iD14 MkI write-only controls

[Will Porter]

Some MkI controls cannot be read back:
- GET stalls for the input gain boost and polarity (feature unit 11),
  the iD key function and the digital input mode.
- GET of the talkback source answers 0, whatever value a SET wrote.

For FU 11 the generic driver creates "Input Gain Control" and "Phase
Inverter Control" and logs "cannot get min/max values".

Add:
- Mic 1/2 Boost Capture Switch (+10 dB)
- Mic 1/2 and Digi 1/2 Polarity Invert Capture Switch
- iD Key Function Playback Enum (ScrollControl, Mono, Mono + Polarity,
  Dim, Talkback)
- Talkback Source Capture Enum (None, Mic 1-2, Digi 1-8)
- Digital In Mode Capture Enum (ADAT, S/PDIF)

and hide the generic FU 11 controls in the MkI map. The named polarity
switches replace the ten values of "Phase Inverter Control". The
controls follow Audient's iD application. It offers gain boost on the
Mic inputs only, and polarity on the Mic and Digi inputs. The device
refuses polarity on Digi 3-8 with EPIPE, in ADAT and in S/PDIF mode
(no ADAT signal connected). So Digi 3-8 have no polarity control.

These controls show the last value the device accepted. Every put sends
its value, also an unchanged one, so that a restore reaches a device
that was reset. At probe the driver sets each control once, so that the
value it shows is true:
- boost and polarity off, iD key ScrollControl, talkback source None:
  the defaults of the iD application and the manual
- S/PDIF: the MkI's measured power-on mode

If that write fails, the control reads "Unknown" (or off) until a put
succeeds. alsactl store saves that value.

The probe write replaces any value the device kept. The device keeps
its values across a module reload or a rebind. On mains power it also
keeps them across a replug. In each of these cases the controls return
to the probe values (for example from ADAT to S/PDIF) until alsactl
restore runs.

Test setup:
- iD14 MkI, firmware 1.1.1
- Bazzite 44, kernel 7.2.9-ogc3.1.fc44
- snd-usb-audio built out of tree from the v7.2.9 sound/usb sources
  and the complete driver (this commit and the later ones)

Results:
- a loopback cable measured the gain boost (+10.0 dB) and the Mic
  polarity
- listening tests: the iD key set to Dim, talkback from Mic 2
- alsactl restored the controls across a replug
- the optical power-on mode, read on macOS 27.0.1 with no Audient
  software running: S/PDIF
- the device accepts the Digi 1/2 polarity request. Its effect was not
  measured.

Assisted-by: Claude:claude-opus-5-5
Signed-off-by: Will Porter <mrwillporter@gmail.com>
---
 sound/usb/mixer_audient_id.c | 144 +++++++++++++++++++++++++++++++----
 sound/usb/mixer_maps.c       |   1 +
 2 files changed, 129 insertions(+), 16 deletions(-)

diff --git a/sound/usb/mixer_audient_id.c b/sound/usb/mixer_audient_id.c
index 5b38590ce..47e16e572 100644
--- a/sound/usb/mixer_audient_id.c
+++ b/sound/usb/mixer_audient_id.c
@@ -19,8 +19,10 @@
  * The protocol comes from Audient's iD application (version 4.4.5 for
  * macOS). USB captures of the application confirmed it.
  *
- * The controls read the device on every get: the front panel changes
- * several of them.
+ * Most controls read the device on every get. Controls whose GET cannot
+ * report the current state show the last value the device accepted.
+ * Every put to these controls sends the value, even when unchanged, so
+ * that alsactl restore also reaches a device that was reset.
  *
  * Get and put need no lock of their own: the control core runs put with
  * card->controls_rwsem held for writing and get with it held for reading.
@@ -40,12 +42,17 @@
 #include "mixer_audient_id.h"
 
 /* Unit IDs */
+#define ID14_IT_DIGITAL		0x01	/* input terminal: optical and coaxial inputs */
 #define ID14_FU_OUT		0x0a	/* feature unit before the outputs */
+#define ID14_FU_IN		0x0b	/* feature unit on the inputs: CN 1-2 Mic, 3-10 Digi */
 #define ID14_ROUTE		0x33	/* routing XU: CN = destination */
 #define ID14_MON		0x36	/* monitor controller XU */
 #define ID14_MIXER		0x3c	/* mixer unit: 14 inputs x 4 outputs */
 
 /* Control selectors */
+#define ID14_IT_OPTICAL_MODE	0x00	/* u32: 0 ADAT, 1 S/PDIF */
+#define ID14_IN_BOOST		0x0b	/* s16: 0x0a00 = +10 dB, 0 = off */
+#define ID14_IN_POLARITY	0x0d
 #define ID14_ROUTE_SOURCE	0x06	/* u8: source of the destination */
 #define ID14_MON_MONO		0x00
 #define ID14_MON_MONO_MODE	0x01
@@ -54,6 +61,8 @@
 #define ID14_MON_DIM		0x05
 #define ID14_MON_DIM_LEVEL	0x06	/* s16, 1/256 dB */
 #define ID14_MON_TALKBACK	0x07
+#define ID14_MON_TALKBACK_SRC	0x08	/* GET always returns 0 */
+#define ID14_MON_ID_KEY		0x10	/* u16: the selector the iD key toggles */
 #define ID14_MON_VOLUME		0x12	/* s16, 1/256 dB; the knob also sets it */
 
 /*
@@ -68,6 +77,7 @@ enum id_kind {
 	ID_BOOL,	/* u8: 1 = on */
 	ID_BOOL_INV,	/* u8: 1 = cut or mute, shown as a switch that is off */
 	ID_VOL,		/* s16 in 1/256 dB; control value 0 ... ID_VOL_MAX, 1 dB steps */
+	ID_BOOST,	/* s16: on = +10 dB */
 	ID_ENUM,	/* item list with device values (struct id_enum) */
 };
 
@@ -78,6 +88,8 @@ struct id_enum {
 	u8 len;		/* bytes on the wire */
 };
 
+#define ID_WO		BIT(0)	/* write-only: GET stalls or does not report writes */
+
 struct id_ctl {
 	const char *name;
 	enum id_kind kind;
@@ -85,12 +97,15 @@ struct id_ctl {
 	u8 cs;
 	u8 cn;		/* first channel number */
 	u8 channels;
+	u8 flags;
+	int init;	/* ID_WO: value written at probe */
 	const struct id_enum *e;
 };
 
 /*
  * The texts have one item more than the values. A put cannot select the last
- * item, "Other": it shows a device value outside the list.
+ * item: a readable control shows it for a device value outside the list
+ * ("Other"), a write-only control while its value is not known ("Unknown").
  */
 #define ID_ENUM_TEXTS(name, texts_, len_, ...)					\
 	static const u32 name##_values[] = { __VA_ARGS__ };			\
@@ -102,11 +117,35 @@ struct id_ctl {
 	ID_ENUM_TEXTS(name, name##_texts, len_, __VA_ARGS__);			\
 	static_assert(ARRAY_SIZE(name##_texts) == ARRAY_SIZE(name##_values) + 1)
 
+/*
+ * iD key function: the value is the monitor-controller selector the key
+ * toggles. ScrollControl (0xffff) toggles nothing: the knob then scrolls
+ * through the HID interface.
+ */
+static const char *const id14_id_key_texts[] = {
+	"ScrollControl", "Mono", "Mono + Polarity", "Dim", "Talkback", "Unknown",
+};
+
+ID_ENUM_DEF(id14_id_key, 2, 0xffff, ID14_MON_MONO, ID14_MON_POLARITY, ID14_MON_DIM,
+	    ID14_MON_TALKBACK);
+
 /* Mono mode: one-speaker sum (Left, Right) or phantom centre. */
 static const char *const id14_mono_mode_texts[] = { "Left", "Centre", "Right", "Other" };
 
 ID_ENUM_DEF(id14_mono_mode, 1, 1, 0, 2);
 
+/* Talkback source: the routing source of the input; none = 0xff. */
+static const char *const id14_talkback_texts[] = {
+	"None", "Mic 1", "Mic 2", "Digi 1", "Digi 2", "Digi 3", "Digi 4", "Digi 5", "Digi 6",
+	"Digi 7", "Digi 8", "Unknown",
+};
+
+ID_ENUM_DEF(id14_talkback, 1, 0xff, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13);
+
+static const char *const id14_optical_texts[] = { "ADAT", "S/PDIF", "Unknown" };
+
+ID_ENUM_DEF(id14_optical, 4, 0, 1);
+
 /*
  * Routing sources for each destination. DAW Thru plays the USB stream
  * directly and bypasses the volume knob: full scale. Main Mix is 0x14/0x15
@@ -122,6 +161,16 @@ ID_ENUM_TEXTS(id14_route_hl, id14_route_texts, 1, 0x18, 0x10, 0x02);
 ID_ENUM_TEXTS(id14_route_hr, id14_route_texts, 1, 0x19, 0x11, 0x03);
 static_assert(ARRAY_SIZE(id14_route_texts) == ARRAY_SIZE(id14_route_ml_values) + 1);
 
+/*
+ * The iD application offers polarity on the Mic and Digi strips, not on
+ * DAW. The MkI accepts it on Digi 1-2 only: CN 5-10 stall in both optical modes
+ * (tested without an ADAT signal).
+ */
+#define ID14_DIGI_POLARITY(n)							\
+	{ .name = "Digi " #n " Polarity Invert Capture Switch", .kind = ID_BOOL,	\
+	  .unit = ID14_FU_IN, .cs = ID14_IN_POLARITY, .cn = 2 + (n), .channels = 1,	\
+	  .flags = ID_WO, .init = 0 }
+
 static const struct id_ctl id14_mk1_ctls[] = {
 	{ .name = "Monitor Speaker Playback Volume", .kind = ID_VOL, .unit = ID14_MON,
 	  .cs = ID14_MON_VOLUME, .channels = 1 },
@@ -152,6 +201,26 @@ static const struct id_ctl id14_mk1_ctls[] = {
 	  .cs = ID14_ROUTE_SOURCE, .cn = 2, .channels = 1, .e = &id14_route_hl },
 	{ .name = "Headphone R Source Playback Enum", .kind = ID_ENUM, .unit = ID14_ROUTE,
 	  .cs = ID14_ROUTE_SOURCE, .cn = 3, .channels = 1, .e = &id14_route_hr },
+	/* Write-only: GET stalls. The probe writes the iD application defaults. */
+	{ .name = "Mic 1 Boost Capture Switch", .kind = ID_BOOST, .unit = ID14_FU_IN,
+	  .cs = ID14_IN_BOOST, .cn = 1, .channels = 1, .flags = ID_WO, .init = 0 },
+	{ .name = "Mic 2 Boost Capture Switch", .kind = ID_BOOST, .unit = ID14_FU_IN,
+	  .cs = ID14_IN_BOOST, .cn = 2, .channels = 1, .flags = ID_WO, .init = 0 },
+	{ .name = "Mic 1 Polarity Invert Capture Switch", .kind = ID_BOOL, .unit = ID14_FU_IN,
+	  .cs = ID14_IN_POLARITY, .cn = 1, .channels = 1, .flags = ID_WO, .init = 0 },
+	{ .name = "Mic 2 Polarity Invert Capture Switch", .kind = ID_BOOL, .unit = ID14_FU_IN,
+	  .cs = ID14_IN_POLARITY, .cn = 2, .channels = 1, .flags = ID_WO, .init = 0 },
+	ID14_DIGI_POLARITY(1), ID14_DIGI_POLARITY(2),
+	{ .name = "iD Key Function Playback Enum", .kind = ID_ENUM, .unit = ID14_MON,
+	  .cs = ID14_MON_ID_KEY, .channels = 1, .flags = ID_WO, .init = 0, .e = &id14_id_key },
+	/* Write-only: GET returns 0 whatever was written. */
+	{ .name = "Talkback Source Capture Enum", .kind = ID_ENUM, .unit = ID14_MON,
+	  .cs = ID14_MON_TALKBACK_SRC, .channels = 1, .flags = ID_WO, .init = 0,
+	  .e = &id14_talkback },
+	/* Write-only: GET stalls. The probe writes the power-on mode, S/PDIF. */
+	{ .name = "Digital In Mode Capture Enum", .kind = ID_ENUM, .unit = ID14_IT_DIGITAL,
+	  .cs = ID14_IT_OPTICAL_MODE, .channels = 1, .flags = ID_WO, .init = 1,
+	  .e = &id14_optical },
 	{ }
 };
 
@@ -159,6 +228,8 @@ static const struct id_ctl id14_mk1_ctls[] = {
 struct id_elem {
 	struct usb_mixer_elem_list list;
 	const struct id_ctl *ctl;
+	long val[2];	/* ID_WO: the last value the device accepted */
+	u8 valid;	/* ID_WO: bit per channel, set when val[] is that value */
 };
 
 /* 0 = -128 dB (mute), 1 dB per step: ID_VOL_MAX = 0 dB. */
@@ -192,6 +263,7 @@ static int id_len(const struct id_ctl *c)
 	case ID_ENUM:
 		return c->e->len;
 	case ID_VOL:
+	case ID_BOOST:
 		return 2;
 	default:
 		return 1;
@@ -203,11 +275,12 @@ static bool id_valid(const struct id_ctl *c, long val)
 	switch (c->kind) {
 	case ID_BOOL:
 	case ID_BOOL_INV:
+	case ID_BOOST:
 		return val == 0 || val == 1;
 	case ID_VOL:
 		return val >= 0 && val <= ID_VOL_MAX;
 	case ID_ENUM:
-		return val >= 0 && val < c->e->items;	/* never "Other" */
+		return val >= 0 && val < c->e->items;	/* never "Other" or "Unknown" */
 	}
 	return false;
 }
@@ -234,6 +307,9 @@ static int id_read(struct usb_mixer_interface *mixer, const struct id_ctl *c,
 	case ID_BOOL_INV:
 		*val = !buf[0];
 		break;
+	case ID_BOOST:
+		*val = raw != 0;
+		break;
 	case ID_VOL:
 		/* the knob moves in whole dB; round anything else to the nearest step */
 		*val = clamp_t(long, DIV_ROUND_CLOSEST(raw, ID_DB(1)) + ID_VOL_MAX,
@@ -262,6 +338,9 @@ static int id_write(struct usb_mixer_interface *mixer, const struct id_ctl *c,
 	case ID_BOOL_INV:
 		buf[0] = !val;
 		break;
+	case ID_BOOST:
+		put_unaligned_le16(val ? ID_DB(10) : 0, buf);
+		break;
 	case ID_VOL:
 		put_unaligned_le16(ID_DB(val - ID_VOL_MAX), buf);
 		break;
@@ -319,9 +398,14 @@ static int id_get(struct snd_kcontrol *kctl, struct snd_ctl_elem_value *v)
 	int err;
 
 	for (i = 0; i < c->channels; i++) {
-		err = id_read(e->list.mixer, c, i, &val);
-		if (err < 0)
-			return err;
+		if (c->flags & ID_WO) {
+			/* No last value (the probe write failed): "Unknown", or off. */
+			val = e->valid & BIT(i) ? e->val[i] : c->kind == ID_ENUM ? c->e->items : 0;
+		} else {
+			err = id_read(e->list.mixer, c, i, &val);
+			if (err < 0)
+				return err;
+		}
 		id_set_value(c, v, i, val);
 	}
 	return 0;
@@ -346,15 +430,25 @@ static int id_put(struct snd_kcontrol *kctl, struct snd_ctl_elem_value *v)
 
 	for (i = 0; i < c->channels; i++) {
 		val = id_get_value(c, v, i);
-		err = id_read(mixer, c, i, &cur);
-		if (err < 0)
-			return err;
-		if (cur == val)
-			continue;
-		changed = 1;
+		if (c->flags & ID_WO) {
+			/* Always send: the device may have been reset since the last write. */
+			if (!(e->valid & BIT(i)) || e->val[i] != val)
+				changed = 1;
+		} else {
+			err = id_read(mixer, c, i, &cur);
+			if (err < 0)
+				return err;
+			if (cur == val)
+				continue;
+			changed = 1;
+		}
 		err = id_write(mixer, c, i, val);
 		if (err < 0)
-			return err;
+			return err;	/* a write-only channel keeps its last accepted value */
+		if (c->flags & ID_WO) {
+			e->val[i] = val;
+			e->valid |= BIT(i);
+		}
 	}
 	return changed;
 }
@@ -364,15 +458,19 @@ static int id_add_ctl(struct usb_mixer_interface *mixer, const struct id_ctl *c)
 	struct snd_kcontrol_new knew = {
 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 		.name = c->name,
-		/* The front panel changes values: user space must not cache them. */
-		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
 		.info = id_info,
 		.get = id_get,
 		.put = id_put,
 	};
 	struct snd_kcontrol *kctl;
 	struct id_elem *e;
+	unsigned int i;
+	int err;
 
+	/* The front panel changes readable values: user space must not cache them. */
+	if (!(c->flags & ID_WO))
+		knew.access |= SNDRV_CTL_ELEM_ACCESS_VOLATILE;
 	if (c->kind == ID_VOL) {
 		knew.access |= SNDRV_CTL_ELEM_ACCESS_TLV_READ;
 		knew.tlv.p = id_vol_tlv;
@@ -385,6 +483,20 @@ static int id_add_ctl(struct usb_mixer_interface *mixer, const struct id_ctl *c)
 	e->list.id = c->unit;
 	e->ctl = c;
 
+	/* A write-only control needs a known value. On failure it reads "Unknown" (or off). */
+	if (c->flags & ID_WO) {
+		for (i = 0; i < c->channels; i++) {
+			err = id_write(mixer, c, i, c->init);
+			if (err < 0) {
+				usb_audio_warn(mixer->chip, "iD14: cannot set '%s' (%d)\n",
+					       c->name, err);
+				continue;
+			}
+			e->val[i] = c->init;
+			e->valid |= BIT(i);
+		}
+	}
+
 	kctl = snd_ctl_new1(&knew, e);
 	if (!kctl) {
 		kfree(e);
diff --git a/sound/usb/mixer_maps.c b/sound/usb/mixer_maps.c
index e147c1a48..63a77f3eb 100644
--- a/sound/usb/mixer_maps.c
+++ b/sound/usb/mixer_maps.c
@@ -528,6 +528,7 @@ static const struct usbmix_name_map audient_id14_map[] = {
 
 /* Audient iD14 MkI: model-specific control map. */
 static const struct usbmix_name_map audient_id14_mk1_map[] = {
+	{ 11, NULL },			/* FU, see mixer_audient_id.c */
 	{ 12, "Monitor Mix Playback" },	/* FU, partial coverage */
 	{ 60, NULL },			/* MU, see mixer_audient_id.c */
 	{}
-- 
2.47.3

[PATCH 5/5] ALSA: usb-audio: Replace the Audient iD14 MkI FU 12 control

[Will Porter]

Feature unit 12 sets the level of the mixer outputs: channels 1-2 Main,
3-4 Cue. Two firmware faults make the generic control wrong on the
MkI:

- GET CUR does not return the FU 12 value. It returns a reply buffer
  that the device shares with FU 10, MU 60 and XU 51. The buffer holds
  the data of the last GET or SET to any of them. So the generic
  sticky-GET check passes, because GET echoes the SET just sent. The
  check then writes the stale value that it read first to channel 1.
- Main L ignores its level, but Main R applies it. So any Main value
  other than 0 dB unbalances the main outputs. audient_id14_map already
  records this asymmetry. A loopback cable measured it: Main R at
  -20 dB, -40 dB and mute changes its output by -20.0, -40.9 and
  -56.6 dB. Main L at the same values changes nothing. Cue L and Cue R
  both work.

Replace the generic control with one of the same name, count and range.
It is "Monitor Mix Playback Volume", with four values from 0 to 127 in
1 dB steps. 127 is 0 dB. Value 0 is mute (0x8000), the floor that
Audient's iD application writes, and the TLV says so. The four values
keep the Main L/R, Cue L/R layout of existing saved ALSA states, but
Main is now held at 0 dB.

The control holds Main at 0 dB, as the iD application does. (The
application has no Main fader and writes 0 dB at launch.) A put always
sends 0 dB to channels 1-2 and returns that value to the caller. Get
reports it too. For Cue the control shows the last value the device
accepted. At probe the driver writes the iD application's launch values
once per channel: Main 0 dB, Cue muted. A channel whose probe write
fails reads as mute until a put succeeds.

The iD14 MkI profile in alsa-ucm-conf writes 127,127,127,127 to this
control at boot and when its HiFi verb starts. The new control accepts
that write: Main stays at 0 dB and Cue goes to 0 dB, the same result as
with the generic control.

Differences from the generic control:
- Value 0 is now mute. It was -127 dB.
- The control holds Main at 0 dB. A Main R attenuation stored with the
  generic control (for example 107, -20 dB) now restores as 0 dB, which
  raises Main R by 20 dB. Main L never applied that attenuation, so
  Main R comes up to the level that Main L already had. FU 12 comes
  before the monitor controller (XU 54) and the headphone level
  (FU 10), so the volume knob still sets the listening level.
- Cue starts muted at every probe. An output routed to the Cue Mix
  keeps that routing across a module reload or a rebind. On mains
  power it also keeps it across a replug. That output is then silent
  until alsactl restore runs. On bus power the MkI returns to DAW Thru
  when it enumerates, so no output is on the Cue Mix at probe.

Test setup:
- iD14 MkI, firmware 1.1.1
- Bazzite 44, kernel 7.2.9-ogc3.1.fc44
- snd-usb-audio built out of tree from the v7.2.9 sound/usb sources
  and the complete driver (this commit and the later ones)

Results:
- the loopback measurements above
- the Cue master, by ear
- a put of 107,107,90,90 reads back 127,127,90,90
- alsactl restore of the Cue level across a replug

Assisted-by: Claude:claude-opus-5-5
Signed-off-by: Will Porter <mrwillporter@gmail.com>
---
 sound/usb/mixer_audient_id.c | 147 +++++++++++++++++++++++++++++++++++
 sound/usb/mixer_maps.c       |   2 +-
 2 files changed, 148 insertions(+), 1 deletion(-)

diff --git a/sound/usb/mixer_audient_id.c b/sound/usb/mixer_audient_id.c
index 47e16e572..b729ca0d7 100644
--- a/sound/usb/mixer_audient_id.c
+++ b/sound/usb/mixer_audient_id.c
@@ -45,6 +45,7 @@
 #define ID14_IT_DIGITAL		0x01	/* input terminal: optical and coaxial inputs */
 #define ID14_FU_OUT		0x0a	/* feature unit before the outputs */
 #define ID14_FU_IN		0x0b	/* feature unit on the inputs: CN 1-2 Mic, 3-10 Digi */
+#define ID14_FU_MIX		0x0c	/* feature unit after the mixer: CN 1-2 Main, 3-4 Cue */
 #define ID14_ROUTE		0x33	/* routing XU: CN = destination */
 #define ID14_MON		0x36	/* monitor controller XU */
 #define ID14_MIXER		0x3c	/* mixer unit: 14 inputs x 4 outputs */
@@ -506,6 +507,149 @@ static int id_add_ctl(struct usb_mixer_interface *mixer, const struct id_ctl *c)
 	return snd_usb_mixer_add_list(&e->list, kctl, false, true);
 }
 
+/*
+ * iD14 MkI FU 12, the mixer output level: CN 1-2 Main, 3-4 Cue. GET RANGE works
+ * (-127 ... 0 dB, 1 dB steps), but GET CUR returns a reply buffer the
+ * device shares with other units, not the FU 12 value. So the generic
+ * control (hidden by the name map) shows stale data, and its sticky-GET
+ * check passes and then writes that stale value to Main L.
+ *
+ * The firmware ignores Main L (CN 1) but applies Main R (CN 2), so any Main
+ * level other than 0 dB unbalances the main outputs (measured with a
+ * loopback; Cue L and Cue R both work). The iD application has no Main
+ * fader and writes 0 dB to Main at launch. This control holds Main at 0 dB:
+ * a put sends 0 dB to CN 1-2 whatever it asks for, and get reports it.
+ *
+ * It keeps the generic control's name and format: four values, 0 ... 127
+ * in 1 dB steps, 127 = 0 dB. Value 0 is mute (0x8000), the floor the iD
+ * application writes. It shows the last value the device accepted, and
+ * every put sends all four channels.
+ */
+#define ID14_FU12_CHANNELS	4
+#define ID14_FU12_MAIN_CHANNELS	2	/* CN 1-2, held at 0 dB */
+#define ID14_FU12_MAX		127
+#define ID14_FU12_MUTE		0
+
+static const DECLARE_TLV_DB_MINMAX_MUTE(id14_fu12_tlv, -12700, 0);
+
+struct id14_fu12 {
+	struct usb_mixer_elem_list list;	/* first: snd_usb_mixer_elem_free */
+	long val[ID14_FU12_CHANNELS];
+	u8 valid;	/* bit per channel */
+};
+
+static s16 id14_fu12_raw(long val)
+{
+	return val == ID14_FU12_MUTE ? ID_DB_MIN : ID_DB(val - ID14_FU12_MAX);
+}
+
+static int id14_fu12_write(struct id14_fu12 *f, unsigned int ch, long val)
+{
+	u8 buf[2];
+	int err;
+
+	put_unaligned_le16(id14_fu12_raw(val), buf);
+	err = id_xfer(f->list.mixer, true, ID14_FU_MIX, UAC_FU_VOLUME, ch + 1, buf, sizeof(buf));
+	if (err < 0)
+		return err;
+	f->val[ch] = val;
+	f->valid |= BIT(ch);
+	return 0;
+}
+
+static int id14_fu12_info(struct snd_kcontrol *kctl, struct snd_ctl_elem_info *uinfo)
+{
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+	uinfo->count = ID14_FU12_CHANNELS;
+	uinfo->value.integer.min = 0;
+	uinfo->value.integer.max = ID14_FU12_MAX;
+	return 0;
+}
+
+static int id14_fu12_get(struct snd_kcontrol *kctl, struct snd_ctl_elem_value *v)
+{
+	struct id14_fu12 *f = snd_kcontrol_chip(kctl);
+	unsigned int ch;
+
+	/* A channel that was never written reads as mute. */
+	for (ch = 0; ch < ID14_FU12_CHANNELS; ch++)
+		v->value.integer.value[ch] = f->valid & BIT(ch) ? f->val[ch] : ID14_FU12_MUTE;
+	return 0;
+}
+
+static int id14_fu12_put(struct snd_kcontrol *kctl, struct snd_ctl_elem_value *v)
+{
+	struct id14_fu12 *f = snd_kcontrol_chip(kctl);
+	unsigned int ch;
+	long val;
+	int err, changed = 0;
+
+	for (ch = 0; ch < ID14_FU12_CHANNELS; ch++)
+		if (v->value.integer.value[ch] < 0 || v->value.integer.value[ch] > ID14_FU12_MAX)
+			return -EINVAL;
+
+	CLASS(snd_usb_lock, pm)(f->list.mixer->chip);
+	if (pm.err < 0)
+		return pm.err;
+
+	/* Main is held at 0 dB: report that back to the caller. */
+	for (ch = 0; ch < ID14_FU12_MAIN_CHANNELS; ch++)
+		v->value.integer.value[ch] = ID14_FU12_MAX;
+
+	for (ch = 0; ch < ID14_FU12_CHANNELS; ch++) {
+		val = v->value.integer.value[ch];
+		if (!(f->valid & BIT(ch)) || f->val[ch] != val)
+			changed = 1;
+		err = id14_fu12_write(f, ch, val);
+		if (err < 0)
+			return err;
+	}
+	return changed;
+}
+
+/*
+ * At probe, write the iD application's launch values: Main at 0 dB (the
+ * iD application has no Main fader) and Cue muted.
+ */
+static int id14_fu12_create(struct usb_mixer_interface *mixer)
+{
+	struct snd_kcontrol_new knew = {
+		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+		.name = "Monitor Mix Playback Volume",
+		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE | SNDRV_CTL_ELEM_ACCESS_TLV_READ,
+		.info = id14_fu12_info,
+		.get = id14_fu12_get,
+		.put = id14_fu12_put,
+		.tlv.p = id14_fu12_tlv,
+	};
+	struct snd_kcontrol *kctl;
+	struct id14_fu12 *f;
+	unsigned int ch;
+	int err;
+
+	f = kzalloc_obj(*f);
+	if (!f)
+		return -ENOMEM;
+	f->list.mixer = mixer;
+	f->list.id = ID14_FU_MIX;
+
+	for (ch = 0; ch < ID14_FU12_CHANNELS; ch++) {
+		err = id14_fu12_write(f, ch, ch < ID14_FU12_MAIN_CHANNELS ?
+				      ID14_FU12_MAX : ID14_FU12_MUTE);
+		if (err < 0)	/* the channel stays unknown and reads as mute */
+			usb_audio_warn(mixer->chip, "iD14: cannot set FU 12 channel %u (%d)\n",
+				       ch + 1, err);
+	}
+
+	kctl = snd_ctl_new1(&knew, f);
+	if (!kctl) {
+		kfree(f);
+		return -ENOMEM;
+	}
+	kctl->private_free = snd_usb_mixer_elem_free;
+	return snd_usb_mixer_add_list(&f->list, kctl, false, true);
+}
+
 /*
  * iD14 MkI mixer crosspoints: CS 1, CN = input * 4 + output, s16 in
  * 1/256 dB. The control value is the raw s16, -128 dB (mute) ... +6 dB;
@@ -632,6 +776,9 @@ int snd_audient_id14_mk1_controls_create(struct usb_mixer_interface *mixer)
 		if (err < 0)
 			return err;
 	}
+	err = id14_fu12_create(mixer);
+	if (err < 0)
+		return err;
 	for (in = 0; in < ARRAY_SIZE(id14_mix_inputs); in++) {
 		for (out = 0; out < ID14_MIX_OUTPUTS; out++) {
 			err = id14_mix_add_ctl(mixer, in, out);
diff --git a/sound/usb/mixer_maps.c b/sound/usb/mixer_maps.c
index 63a77f3eb..2228fd34f 100644
--- a/sound/usb/mixer_maps.c
+++ b/sound/usb/mixer_maps.c
@@ -529,7 +529,7 @@ static const struct usbmix_name_map audient_id14_map[] = {
 /* Audient iD14 MkI: model-specific control map. */
 static const struct usbmix_name_map audient_id14_mk1_map[] = {
 	{ 11, NULL },			/* FU, see mixer_audient_id.c */
-	{ 12, "Monitor Mix Playback" },	/* FU, partial coverage */
+	{ 12, NULL },			/* FU, see mixer_audient_id.c */
 	{ 60, NULL },			/* MU, see mixer_audient_id.c */
 	{}
 };
-- 
2.47.3

Re: [PATCH 0/5] ALSA: usb-audio: Audient iD14 MkI vendor controls

[Takashi Iwai]

On Tue, 20 Oct 2026 01:01:54 +0200,
Will Porter wrote:
> 
> The Audient iD14 MkI (2708:0002) keeps its monitor section, output
> routing, mixer and input options on vendor extension units. It also
> uses feature units whose descriptors declare no controls. On Linux a
> user cannot change the routing. The device powers up with every output
> on DAW Thru, which bypasses the volume knob.
> 
> This series adds those controls in a new mixer_audient_id.c, one group
> per patch. A MkI-only name map hides the generic controls that each
> group replaces. The MkII keeps audient_id14_map.
> 
> Scope: only the iD14 MkI is supported, and only its USB ID reaches the
> new code. Other Audient iD models keep the generic driver. Their units
> may differ, and this series does not cover them. The file follows
> mixer_scarlett2.c, which began with one model and added others through
> per-model tables. Names with id14_ hold the MkI's unit IDs and tables. A
> later iD model can add its own tables to this file.
> 
> sound for-next also has mixer_evo.c for the Audient EVO 4 (2708:0006).
> EVO and iD are separate Audient product lines. The iD14 MkI uses other
> units and a larger control set: a monitor controller, output routing, a
> 14 x 4 mixer and write-only controls. So this series keeps the iD line
> in its own file.
> 
> At probe the driver writes only controls that it cannot read back: the
> write-only controls (patch 4) and FU 12 (patch 5). They get the launch
> values of Audient's iD application. If a probe write fails, the control
> shows the fallback value that those patches describe. The driver does
> not write the routing or the mix. User space (alsactl, an application)
> sets the rest of the iD application's launch state.
> 
> There is no resume code. Every write to a write-only control reaches
> the device, so alsactl restore also repairs a device that was reset.
> The state across a suspend depends on the power source:
> - On USB bus power, a system suspend re-enumerates the device.
> - With its mains adapter connected, the device keeps its state across a
>   system suspend. This is also true when the host controller resets the
>   device and the card stays. The sampled readable controls did not
>   change.
> - A runtime suspend left the readable controls unchanged on both power
>   sources, with no reset logged. A runtime suspend is possible only
>   after usbhid releases the HID interface.
> 
> Patch 5 replaces the generic "Monitor Mix Playback Volume" (FU 12) with
> one of the same name, count and range. FU 12 GET CUR returns stale data
> from other units. Its Main L channel ignores writes, but Main R applies
> them. audient_id14_map already notes this asymmetry. The new control
> holds Main at 0 dB. This is a deliberate change for existing users: a
> Main R attenuation set through the generic control no longer applies.
> 
> The protocol comes from Audient's iD application (version 4.4.5 for
> macOS). USB captures of the application confirmed it.
> 
> Test setup:
> - iD14 MkI, firmware 1.1.1
> - Bazzite 44, kernel 7.2.9-ogc3.1.fc44
> - snd-usb-audio built out of tree from the v7.2.9 sound/usb sources
>   with this series applied
> 
> Tests:
> - listening tests: routing, dim, talkback, Cue
> - a loopback cable: gain boost, polarity, FU 12 per channel
> - alsactl store and restore across a replug
> - an out-of-list routing value
> - a runtime suspend
> - three system suspends (S3) with control reads running at about 3000
>   per second: no read failed after a resume
> - the optical power-on mode, read on macOS 27.0.1 with no Audient
>   software running
> 
> The series is based on sound for-next a4ef328ce3b3. Each patch builds
> on its own there with make W=1 sound/usb/. The hardware tests used the
> complete series on 7.2.9 sources, where snd_usb_mixer_add_list() has no
> look_for_empty argument. The series passes true, which keeps that
> behaviour.
> 
> Will Porter (5):
>   ALSA: usb-audio: Give the Audient iD14 MkI its own mixer map
>   ALSA: usb-audio: Add Audient iD14 MkI monitor and routing controls
>   ALSA: usb-audio: Add Audient iD14 MkI mixer matrix
>   ALSA: usb-audio: Add Audient iD14 MkI write-only controls
>   ALSA: usb-audio: Replace the Audient iD14 MkI FU 12 control
> 
>  sound/usb/Makefile           |   1 +
>  sound/usb/mixer_audient_id.c | 790 +++++++++++++++++++++++++++++++++++
>  sound/usb/mixer_audient_id.h |   7 +
>  sound/usb/mixer_maps.c       |  10 +-
>  sound/usb/mixer_quirks.c     |   4 +
>  5 files changed, 811 insertions(+), 1 deletion(-)
>  create mode 100644 sound/usb/mixer_audient_id.c
>  create mode 100644 sound/usb/mixer_audient_id.h

FYI, I postpone this to 7.5, as 7.4 merge window was already opened
and this PR has too big changes as a last-minute fix.


thanks,

Takashi

Re: [PATCH 0/5] ALSA: usb-audio: Audient iD14 MkI vendor controls

[Christian Ruppert]

[-- Attachment #1: Type: text/plain, Size: 6569 bytes --]

Hi Will,

On Mon, Oct 19, 2026 at 06:01:54PM -0500, Will Porter wrote:
> [...]
> 
> sound for-next also has mixer_evo.c for the Audient EVO 4 (2708:0006).
> EVO and iD are separate Audient product lines. The iD14 MkI uses other
> units and a larger control set: a monitor controller, output routing, a
> 14 x 4 mixer and write-only controls. So this series keeps the iD line
> in its own file.
> 
> [...]

I took a look at this question and it seems like we can share the majority
of code in the EVO driver by complementing it with the following features:
- variable width read/write
- caching of write-only values
- enum data type

Most of these changes should be trivial as the EVO driver controls are
also structured in tabular form and the driver was intended from the start
to be extensible to the evo8 and possibly other hardware. See below diff
for an example of how to support the first point (just to illustrate these
changes are minor, others should be of similar extent, not properly tested
so use with caution).

Adding those features should allow to simply add a new table (allocated at
probe time for WO caching) with entries for most id14 controls. The only
part which seems more problematic is probably FU12 which looks like it
requires some custom logic and would still need actual code.

Happy to support a common driver activity and rename everything to audient
if you think this makes sense in order to reduce code size but no problem
if you think this is too complex to manage, up to you.

  Christian

diff --git a/sound/usb/mixer_evo.c b/sound/usb/mixer_evo.c
index c327b82c8d2d..92f3c6d108a9 100644
--- a/sound/usb/mixer_evo.c
+++ b/sound/usb/mixer_evo.c
@@ -31,9 +31,13 @@ enum snd_evo_type {
 	SND_EVO_TYPE_NCTYPES
 };
 
+#define SND_EVO_CTRL_FLAGS_SIGNED (1L<<0)
+#define SND_EVO_CTRL_FLAGS_INVERT (1L<<1)
+
 static const struct snd_evo_ctrl_type {
 	snd_ctl_elem_type_t type;
-	bool invert;
+	unsigned long width;
+	unsigned long flags;
 	union {
 		int integer;
 	} min;
@@ -45,6 +49,7 @@ static const struct snd_evo_ctrl_type {
 } snd_evo_ctypes[SND_EVO_TYPE_NCTYPES] = {
 	[SND_EVO_TYPE_MONITOR] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
+		.width = 2,
 		.min.integer = 0,
 		.max.integer = 127,
 		.wValue = 0x0000,
@@ -52,7 +57,7 @@ static const struct snd_evo_ctrl_type {
 	},
 	[SND_EVO_TYPE_PHANTOM] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
-		.invert = false,
+		.width = 4,
 		.min.integer = 0,
 		.max.integer = 1,
 		.wValue = 0x0000,
@@ -60,7 +65,8 @@ static const struct snd_evo_ctrl_type {
 	},
 	[SND_EVO_TYPE_MUTE] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
-		.invert = true,
+		.width = 4,
+		.flags = SND_EVO_CTRL_FLAGS_INVERT,
 		.min.integer = 0,
 		.max.integer = 1,
 		.wValue = 0x0200,
@@ -68,7 +74,8 @@ static const struct snd_evo_ctrl_type {
 	},
 	[SND_EVO_TYPE_MUTE_OUT] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
-		.invert = true,
+		.width = 4,
+		.flags = SND_EVO_CTRL_FLAGS_INVERT,
 		.min.integer = 0,
 		.max.integer = 1,
 		.wValue = 0x0100,
@@ -76,6 +83,8 @@ static const struct snd_evo_ctrl_type {
 	},
 	[SND_EVO_TYPE_MIXER] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
+		.width = 2,
+		.flags = SND_EVO_CTRL_FLAGS_SIGNED,
 		.min.integer = -128 * 256,
 		.max.integer = 6 * 256,
 		.wValue = 0x0100,
@@ -280,24 +289,24 @@ static int snd_ctl_evo_boolean_get(struct snd_kcontrol *kctl,
 	int i;
 
 	for (i = 0; i < hwchan; i++) {
-		u32 buf;
+		u32 buf = 0;
 		int ret;
 
 		ret = snd_evo_get_cur(mixer, value + i, index,
-				      &buf, sizeof(buf));
+				      &buf, ctype->width);
 		if (ret < 0)
 			return ret;
 
 		ctl_val->value.integer.value[i] = le32_to_cpu(buf) ? 1 : 0;
 
-		if (ctype->invert)
+		if (ctype->flags & SND_EVO_CTRL_FLAGS_INVERT)
 			ctl_val->value.integer.value[i] ^= 0x1;
 	}
 
 	for (; i < nchan; i++)
-		ctl_val->value.integer.value[i] = ctype->invert
-							? ctype->max.integer
-							: ctype->min.integer;
+		ctl_val->value.integer.value[i]
+				= (ctype->flags & SND_EVO_CTRL_FLAGS_INVERT)
+				  ? ctype->max.integer : ctype->min.integer;
 
 	return 0;
 }
@@ -317,15 +326,15 @@ static int snd_ctl_evo_boolean_set(struct snd_kcontrol *kctl,
 	int i;
 
 	for (i = 0; i < hwchan; i++) {
-		u32 rbuf;
+		u32 rbuf = 0;
 		u32 buf = cpu_to_le32(ctl_val->value.integer.value[i] ? 1 : 0);
 		int ret;
 
-		if (ctype->invert)
+		if (ctype->flags & SND_EVO_CTRL_FLAGS_INVERT)
 			buf ^= 0x1;
 
 		ret = snd_evo_get_cur(mixer, value + i, index,
-				      &rbuf, sizeof(rbuf));
+				      &rbuf, ctype->width);
 		if (ret < 0)
 			return ret;
 
@@ -333,7 +342,7 @@ static int snd_ctl_evo_boolean_set(struct snd_kcontrol *kctl,
 			changed = 1;
 
 			ret = snd_evo_set_cur(mixer, value + i, index,
-					      &buf, sizeof(buf));
+					      &buf, ctype->width);
 			if (ret < 0)
 				return ret;
 		}
@@ -342,6 +351,19 @@ static int snd_ctl_evo_boolean_set(struct snd_kcontrol *kctl,
 	return changed;
 }
 
+static inline long buf2cpu(const struct snd_evo_ctrl_type *const ctype, u32 in)
+{
+	const u32 u = le32_to_cpu(in);
+
+	if  (ctype->flags & SND_EVO_CTRL_FLAGS_SIGNED) {
+		const int sh = 32 - ctype->width * 8;
+		const s32 s = u << sh;
+
+		return s >> sh;
+	} else
+		return u;
+}
+
 static int snd_ctl_evo_integer_get(struct snd_kcontrol *kctl,
 				   struct snd_ctl_elem_value *ctl_val)
 {
@@ -357,16 +379,16 @@ static int snd_ctl_evo_integer_get(struct snd_kcontrol *kctl,
 	int i;
 
 	for (i = 0; i < hwchan; i++) {
-		u16 buf;
-		s16 val;
+		u32 buf = 0;
+		s32 val;
 		int ret;
 
 		ret = snd_evo_get_cur(mixer, value + i, index,
-				      &buf, sizeof(buf));
+				      &buf, ctype->width);
 		if (ret < 0)
 			return ret;
 
-		val = le16_to_cpu(buf);
+		val = buf2cpu(ctype, buf);
 		ctl_val->value.integer.value[i] = val;
 	}
 
@@ -391,16 +413,16 @@ static int snd_ctl_evo_integer_set(struct snd_kcontrol *kctl,
 	int i;
 
 	for (i = 0; i < hwchan; i++) {
-		s16 rbuf;
-		s16 buf = cpu_to_le16(ctl_val->value.integer.value[i]);
+		s32 rbuf = 0;
+		s32 buf = cpu_to_le32(ctl_val->value.integer.value[i]);
 		int ret;
 
 		ret = snd_evo_get_cur(mixer, value + i, index,
-				      &rbuf, sizeof(rbuf));
+				      &rbuf, ctype->width);
 		if (ret < 0)
 			return ret;
 
-		if (rbuf != buf) {
+		if (buf2cpu(ctype, rbuf) != ctl_val->value.integer.value[i]) {
 			changed = 1;
 
 			ret = snd_evo_set_cur(mixer, value + i, index,

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 870 bytes --]

Re: [PATCH 0/5] ALSA: usb-audio: Audient iD14 MkI vendor controls

[Will Porter]

Hi Christian,

On Mon, Oct 26, 2026 at 07:36:24PM +0100, Christian Ruppert wrote:
> I took a look at this question and it seems like we can share the majority
> of code in the EVO driver by complementing it with the following features:
> - variable width read/write
> - caching of write-only values
> - enum data type

Thanks for looking into this so closely, and for the fixes. I like
the idea of one driver, and I'd like to find out whether the iD line fits.

Your TLV in patch 4/4 is the same one I use for the iD14 matrix: same
unit 0x3C, s16 in 1/256 dB, -128 to +6 dB. That made me wonder whether
the iD14 matrix could use your MIXER type almost as it is. Its channel
number is input * 4 + output, so Main L/R and Cue L/R of each input
are adjacent, like your stereo pairs. Could we expose it as 28
controls with two values each, rather than my 56 single-value ones?
An input's level and pan in a mix set its L and R values together,
so a pair seems a natural fit. Does that look right to you?

> The only part which seems more problematic is probably FU12 which looks
> like it requires some custom logic and would still need actual code.

Agreed. I'd keep FU 12 as its own code.

A few questions about the rest:

1. Read before write. As I understand it, the put handlers in
   mixer_evo.c read the value first to see if it changed. On the iD14,
   GET stalls for mic boost, input polarity, optical mode and the iD
   key function, so a put that reads first would fail there. Talkback
   source always reads 0, so a read would hide real changes. Could
   these write-only controls skip GET in both get and put, with get
   returning the cached value? And could every put still send the
   value, even when it matches the cache, so that "alsactl restore"
   reaches a device that was reset?

2. The cache. My driver writes a known value at probe (off or none,
   and for optical mode its measured power-on mode, S/PDIF) and
   updates the cache only after a full-length write. If the probe
   write fails, an enum reads "Unknown" and a switch reads off. Would
   that approach work for you?

3. Control entries. The iD14 table uses 16 unit/selector pairs and
   explicit control names, such as "Main Out L Source Playback Enum".
   It also needs volumes in 1 dB steps (0..128, stored as s16
   1/256 dB), a boost switch that writes 0x0a00 for on, and enums
   that map items to device values, plus an "Other" item that only
   get reports, for values outside the list. Would it make sense to
   move the unit, selector and an optional full name into each control
   entry, and add the new value formats (1 dB volumes, boost, enum)
   as ctypes? Or would you structure it differently?

4. Checks. My helper returns -EIO on a short read or write, before
   it decodes a value or updates the cache. My matrix put also rejects
   values outside -128..+6 dB, and get clamps what it reads back.
   Could the shared code keep these checks?

I don't have a firm view yet on which way is better. If the iD14
fits the table without many special cases, one driver seems clearly
worth it. If it needs a lot of per-device branches, two smaller files
might be easier to read and review. What do you think, now that you
have seen what the iD14 needs?

If we do combine them, the order I imagined is: your four fixes first,
then the rename to Audient, then the generic changes, then the iD14
tables on top as v2 of my series.

In that case, would you prefer to do the rename and the generic part
yourself? The rename would also touch MAINTAINERS; how would you like
to handle review of the iD14 parts? I can write the iD14 parts and
test them on my MkI. I don't have an EVO 4, so would you be able to
test that side? And which base should I work against, sound for-next
once your fixes are in? I'm also not sure how a combined change
should reach Takashi: as one series, or as two with a stated
dependency.

Thanks,
Will

Re: [PATCH 0/5] ALSA: usb-audio: Audient iD14 MkI vendor controls

[Takashi Iwai]

On Mon, 26 Oct 2026 22:44:50 +0100,
Will Porter wrote:
> 
> Hi Christian,
> 
> On Mon, Oct 26, 2026 at 07:36:24PM +0100, Christian Ruppert wrote:
> > I took a look at this question and it seems like we can share the majority
> > of code in the EVO driver by complementing it with the following features:
> > - variable width read/write
> > - caching of write-only values
> > - enum data type
> 
> Thanks for looking into this so closely, and for the fixes. I like
> the idea of one driver, and I'd like to find out whether the iD line fits.
> 
> Your TLV in patch 4/4 is the same one I use for the iD14 matrix: same
> unit 0x3C, s16 in 1/256 dB, -128 to +6 dB. That made me wonder whether
> the iD14 matrix could use your MIXER type almost as it is. Its channel
> number is input * 4 + output, so Main L/R and Cue L/R of each input
> are adjacent, like your stereo pairs. Could we expose it as 28
> controls with two values each, rather than my 56 single-value ones?
> An input's level and pan in a mix set its L and R values together,
> so a pair seems a natural fit. Does that look right to you?
> 
> > The only part which seems more problematic is probably FU12 which looks
> > like it requires some custom logic and would still need actual code.
> 
> Agreed. I'd keep FU 12 as its own code.
> 
> A few questions about the rest:
> 
> 1. Read before write. As I understand it, the put handlers in
>    mixer_evo.c read the value first to see if it changed. On the iD14,
>    GET stalls for mic boost, input polarity, optical mode and the iD
>    key function, so a put that reads first would fail there. Talkback
>    source always reads 0, so a read would hide real changes. Could
>    these write-only controls skip GET in both get and put, with get
>    returning the cached value? And could every put still send the
>    value, even when it matches the cache, so that "alsactl restore"
>    reaches a device that was reset?
> 
> 2. The cache. My driver writes a known value at probe (off or none,
>    and for optical mode its measured power-on mode, S/PDIF) and
>    updates the cache only after a full-length write. If the probe
>    write fails, an enum reads "Unknown" and a switch reads off. Would
>    that approach work for you?
> 
> 3. Control entries. The iD14 table uses 16 unit/selector pairs and
>    explicit control names, such as "Main Out L Source Playback Enum".
>    It also needs volumes in 1 dB steps (0..128, stored as s16
>    1/256 dB), a boost switch that writes 0x0a00 for on, and enums
>    that map items to device values, plus an "Other" item that only
>    get reports, for values outside the list. Would it make sense to
>    move the unit, selector and an optional full name into each control
>    entry, and add the new value formats (1 dB volumes, boost, enum)
>    as ctypes? Or would you structure it differently?
> 
> 4. Checks. My helper returns -EIO on a short read or write, before
>    it decodes a value or updates the cache. My matrix put also rejects
>    values outside -128..+6 dB, and get clamps what it reads back.
>    Could the shared code keep these checks?
> 
> I don't have a firm view yet on which way is better. If the iD14
> fits the table without many special cases, one driver seems clearly
> worth it. If it needs a lot of per-device branches, two smaller files
> might be easier to read and review. What do you think, now that you
> have seen what the iD14 needs?
> 
> If we do combine them, the order I imagined is: your four fixes first,
> then the rename to Audient, then the generic changes, then the iD14
> tables on top as v2 of my series.
> 
> In that case, would you prefer to do the rename and the generic part
> yourself? The rename would also touch MAINTAINERS; how would you like
> to handle review of the iD14 parts? I can write the iD14 parts and
> test them on my MkI. I don't have an EVO 4, so would you be able to
> test that side? And which base should I work against, sound for-next
> once your fixes are in? I'm also not sure how a combined change
> should reach Takashi: as one series, or as two with a stated
> dependency.

Well, it's all up to you guys :)
Just arrange between Christian and you, then resubmit, either v2 or
additional patches.  I'll be traveling from tomorrow and can't react
for a few days, in anyway.


thanks,

Takashi

Re: [PATCH 0/5] ALSA: usb-audio: Audient iD14 MkI vendor controls

[Christian Ruppert]

Hi Will,

On Mon, Oct 26, 2026 at 04:44:50PM -0500, Will Porter wrote:
> On Mon, Oct 26, 2026 at 07:36:24PM +0100, Christian Ruppert wrote:
> > I took a look at this question and it seems like we can share the majority
> > of code in the EVO driver by complementing it with the following features:
> > - variable width read/write
> > - caching of write-only values
> > - enum data type
> 
> Thanks for looking into this so closely, and for the fixes. I like
> the idea of one driver, and I'd like to find out whether the iD line fits.
> 
> Your TLV in patch 4/4 is the same one I use for the iD14 matrix: same
> unit 0x3C, s16 in 1/256 dB, -128 to +6 dB. That made me wonder whether
> the iD14 matrix could use your MIXER type almost as it is.

Agreed. If my understanding is correct, this type could be reused without
any modifications. The others would have to be newly defined due to
different unit IDs/control selectors. BTW: the mixer matrix seems to be
identical also for the EVO8 so chances are it's the same for most audient
devices and we could simply use a width and height parameter to generate
it in a loop.

> Its channel
> number is input * 4 + output, so Main L/R and Cue L/R of each input
> are adjacent, like your stereo pairs. Could we expose it as 28
> controls with two values each, rather than my 56 single-value ones?
> An input's level and pan in a mix set its L and R values together,
> so a pair seems a natural fit. Does that look right to you?

This is exactly what the stereo pairs do for the EVO. For example, mic 1
shows up as one stereo pair which can be either recorded on both channels
(paned between L and R) or exclusively on the left one if it's connected
to a stereo mic. Same for mic 2 (which can be used as the right channel
of a stereo mic or an independently paned mic). The same principle applies
for the L and R outputs of the monitor and USB main out where it seems a
bit more quirky but is coherent with the Mics. That said, the existing
table system would also allow for individual channels or grouping them in
"mini-matrices of four" but neither seemed right when looking at them in
alsamixer and so I stuck with one stereo mixer for each (mono) input
channel, similar to most mixing consoles.

> > The only part which seems more problematic is probably FU12 which looks
> > like it requires some custom logic and would still need actual code.
> 
> Agreed. I'd keep FU 12 as its own code.
> 
> A few questions about the rest:
> 
> 1. Read before write. As I understand it, the put handlers in
>    mixer_evo.c read the value first to see if it changed. On the iD14,
>    GET stalls for mic boost, input polarity, optical mode and the iD
>    key function, so a put that reads first would fail there. Talkback
>    source always reads 0, so a read would hide real changes. Could
>    these write-only controls skip GET in both get and put, with get
>    returning the cached value? And could every put still send the
>    value, even when it matches the cache, so that "alsactl restore"
>    reaches a device that was reset?

My view of the WO implementation would be to add three flags: cache, init
and force_write:
- If cache is set, the values will be cached and the channel not marked as
  volatile. No need to read back actual values from USB before a write in
  this case. This could also be used in the EVO for the mixer matrix which
  doesn't have physical controls that can change values while the driver
  doesn't look. Didn't implement it to not complicate the driver with
  unnecessary caching but if we need caching anyway we should use it.
- If init is set, the driver will initialize the control at probe. The EVO
  mixer matrix' initial read returns a wrong value so initialization would
  be great. Also not implemented today because there's no need to complicate
  the driver for a control which must be fiddled with anyway before it is
  useful but if we have the feature we should use it.
- If force_write is set, the driver will always write the value, no matter
  if a cached (or previously read) value is identical. IMHO this is mainly
  required for broken or quirky controls but I'm a bit undecided if it
  would really hurt to simply make this behaviour the default for
  everything.

> 2. The cache. My driver writes a known value at probe (off or none,
>    and for optical mode its measured power-on mode, S/PDIF) and
>    updates the cache only after a full-length write. If the probe
>    write fails, an enum reads "Unknown" and a switch reads off. Would
>    that approach work for you?

This is very much in line with what I was thinking, see above.

> 3. Control entries. The iD14 table uses 16 unit/selector pairs and
>    explicit control names, such as "Main Out L Source Playback Enum".
>    It also needs volumes in 1 dB steps (0..128, stored as s16
>    1/256 dB), a boost switch that writes 0x0a00 for on, and enums
>    that map items to device values, plus an "Other" item that only
>    get reports, for values outside the list. Would it make sense to
>    move the unit, selector and an optional full name into each control
>    entry, and add the new value formats (1 dB volumes, boost, enum)
>    as ctypes? Or would you structure it differently?

This is several questions in one, let me try not to forget an answer ;)
- The intent of the control types was to associate unit/selector pairs
  with data types. I would add a new ctype for each unit/selector pair
  but am open to move unit/selector to the controls and only leave the
  data type definition in ctype (which will then become rather a dtype)
  if it significantly reduces repetition. I'm afraid it might just shift
  repetition to the controls table, though. Btw: I like the unit/selector
  macros, will introduce this also for the EVO.
- I don't have a preference between explicit control names and the
  basename/suffix system the EVO driver currently uses. If you prefer we
  can simply replace the basename with a full name and remove the flags
  field in the controls.
- The boost switch writing 0x0 for 0dB gain and 0x0a00 for 10dB gain looks
  suspiciously like a volume control between 0dB and 10dB * 256steps/dB.
  Does this control only accept these two values or can we simply
  implement it as a standard volume type controlling a mic pre-amp? If
  it's only 0xa00 or 0x0 I would suggest to slightly redefine the boolean
  type to use the max value for true and the min value for false which
  would also be an elegant way to remove the inversion flag.
- We definitely need a new snd_evo_type entry and get/set functions for
  enums, up to you to define those in the most suitable manner for the
  id14.

> 4. Checks. My helper returns -EIO on a short read or write, before
>    it decodes a value or updates the cache. My matrix put also rejects
>    values outside -128..+6 dB, and get clamps what it reads back.
>    Could the shared code keep these checks?

Sure, error management is always good to have. I never encountered any
short reads/writes or out of range reads with the EVO so I didn't add any
logic for this until now. Also, for the controls I checked, the EVO
cleanly rejects out-of-range writes but if the id14 doesn't we should add
those checks as well.

> I don't have a firm view yet on which way is better. If the iD14
> fits the table without many special cases, one driver seems clearly
> worth it. If it needs a lot of per-device branches, two smaller files
> might be easier to read and review. What do you think, now that you
> have seen what the iD14 needs?

I think we can put everything except for FU12 into the tables and the EVO
driver would even benefit from the added features (see above).

> If we do combine them, the order I imagined is: your four fixes first,
> then the rename to Audient, then the generic changes, then the iD14
> tables on top as v2 of my series.

Agreed. Renaming the file first might turn out to be annoying because it's
the one thing which might create rebase conflicts we'll have to deal with
while we work on this but it's probably preferable to keep as much of the
commit history as possible after the rename.

> In that case, would you prefer to do the rename and the generic part
> yourself?

I suppose we can cut one testing loop if I do the part of the generic part
that touches the EVO myself so I can do that, no problem.

> The rename would also touch MAINTAINERS; how would you like
> to handle review of the iD14 parts?

I would definitely prefer to list both of us as maintainers. Practically
all code will be shared and I can't speak for the id14 in any way.

> I can write the iD14 parts and
> test them on my MkI. I don't have an EVO 4, so would you be able to
> test that side? And which base should I work against, sound for-next
> once your fixes are in?

It shouldn't make a huge difference because we're rather independent on
this file. I'll probably prepare everything on 7.3 and then rebase it onto
sound/master to test it there and submit (that's what I did until now, but
for-next is also fine). I suggest I submit an RFC with the generic part
that you can apply locally to work against (and potentially adjust) before
you submit everything in a final series which, if everything goes well, I
only need to retest and tag.

> I'm also not sure how a combined change
> should reach Takashi: as one series, or as two with a stated
> dependency.

Re: [PATCH 0/5] ALSA: usb-audio: Audient iD14 MkI vendor controls

[Will Porter]

Hi Christian,

On Wed, Oct 28, 2026 at 12:21:51AM +0100, Christian Ruppert wrote:
> BTW: the mixer matrix seems to be identical also for the EVO8 so
> chances are it's the same for most audient devices and we could
> simply use a width and height parameter to generate it in a loop.

That sounds good to me. On the iD14 it would be 14 inputs by 4
outputs.

> My view of the WO implementation would be to add three flags: cache,
> init and force_write:

These look right to me. As per-control flags, you could set init on the
EVO matrix, and for the iD14 entries, could we set it only on the
write-only controls? The matrix, routing and readable monitor controls
keep their values across a replug on mains power, so I'd leave those
untouched at probe. Would each entry also carry its init value? On the
iD14 most start at off or the first item, but optical mode starts at
S/PDIF.

I'd keep force_write on the cached write-only controls, as a precaution
against a reset that leaves the card registered. I haven't seen that
on the iD14: the resets I've seen re-enumerate it and run probe again.
For the readable controls, skipping an unchanged write seems fine to me.

> - The intent of the control types was to associate unit/selector
>   pairs with data types. I would add a new ctype for each
>   unit/selector pair [...]
> - I don't have a preference between explicit control names and the
>   basename/suffix system the EVO driver currently uses. If you prefer
>   we can simply replace the basename with a full name and remove the
>   flags field in the controls.

Yes, full names would make the iD14 table easier to check. And
one ctype per unit/selector pair is fine with me.

> - The boost switch writing 0x0 for 0dB gain and 0x0a00 for 10dB gain
>   looks suspiciously like a volume control between 0dB and 10dB *
>   256steps/dB. Does this control only accept these two values or can
>   we simply implement it as a standard volume type controlling a mic
>   pre-amp?

Your guess was correct! The device answers no RANGE request for it, so
I tried intermediate values with a loopback cable: 0x0100, 0x0280 and
0x0500 gave +1, +2.5 and +5 dB on both mic inputs, each tested
successfully within 0.01 dB of nominal. I didn't test outside 0..+10 dB
though.

Even so, I'd like to keep it as a switch in this series, because the
iD14's documentation describes a fixed +10 dB boost. Your max-for-true,
min-for-false boolean would fit that, with 0 and 0x0a00. A 0..10 dB
volume could follow as its own patch if people want it later. Does that
sound reasonable?

> - We definitely need a new snd_evo_type entry and get/set functions
>   for enums, up to you to define those in the most suitable manner
>   for the id14.

OK, I'll write the enum type with the iD14 tables.

> Sure, error management is always good to have. [...] Also, for the
> controls I checked, the EVO cleanly rejects out-of-range writes but
> if the id14 doesn't we should add those checks as well.

I haven't tested whether the iD14 rejects them. Could the generic put
handlers reject values outside each control's writable ALSA range with
-EINVAL, before converting them to device values? That would cover
both devices.

> I would definitely prefer to list both of us as maintainers.

Okay, let's do that.

> I suggest I submit an RFC with the generic part that you can apply
> locally to work against (and potentially adjust) before you submit
> everything in a final series which, if everything goes well, I only
> need to retest and tag.

That works for me. I'll carry your rename and generic patches in the
final series, with your authorship and Signed-off-by kept and mine
added, followed by the iD14 patches. Are your four fixes still going in
separately first? And could you include the base commit in the RFC?

Thanks,
Will

[RFC PATCH 00/11] Re: ALSA: usb-audio: Audient iD14 MkI vendor controls

[Christian Ruppert]

Hi Will,

As discussed here an RFC to prepare iD14 support. It goes on top of the
previous patch set (minor fixes and tlv addition) which I hope can still
make it into 7.4.

The driver was restructured as agreed, with one (short) patch per item to
make the changes as understandable as possible. Up to you to squash them
into fewer ones before submitting everything in order to keep the final
patch series short.

The patches were generated for sound/master commit 603a4df9e6ae60a26adb335f
and tested with linux-7.3.1. In both cases, the "minor fixes and tlv
addition" patch series was applied first. Note that I could not fully test
everything using the EVO4 hardware, some of the newly possible
configurations are only usable with the iD14.

See below for a few more comments about the technical details.

  Christian

On Tue, Oct 27, 2026 at 09:36:23PM -0500, Will Porter wrote:
> On Wed, Oct 28, 2026 at 12:21:51AM +0100, Christian Ruppert wrote:
> > BTW: the mixer matrix seems to be identical also for the EVO8 so
> > chances are it's the same for most audient devices and we could
> > simply use a width and height parameter to generate it in a loop.
> 
> That sounds good to me. On the iD14 it would be 14 inputs by 4
> outputs.

OK, defined as a list of names, see patch 11.

> > My view of the WO implementation would be to add three flags: cache,
> > init and force_write:
> 
> These look right to me. As per-control flags, you could set init on the
> EVO matrix, and for the iD14 entries, could we set it only on the
> write-only controls? The matrix, routing and readable monitor controls
> keep their values across a replug on mains power, so I'd leave those
> untouched at probe. Would each entry also carry its init value? On the
> iD14 most start at off or the first item, but optical mode starts at
> S/PDIF.

Actually, the matrix settings also seem to survive a reboot on the EVO (as
long as the device remains powered) so finally I decided not to initialize
at enumeration either to make the behaviour consistent with the iD14.

Init values are defined in the control type and apply to both the hardware
(if the INIT_HW flag is set) and the cache (e.g. if the FORCE_SET flag is
set without INIT_HW).

> I'd keep force_write on the cached write-only controls, as a precaution
> against a reset that leaves the card registered. I haven't seen that
> on the iD14: the resets I've seen re-enumerate it and run probe again.
> For the readable controls, skipping an unchanged write seems fine to me.

OK, the flags should be rather orthogonal. I couldn't test all combinations
with the EVO, though, so don't hesitate to fix potential issues you might
discover.

> > - The intent of the control types was to associate unit/selector
> >   pairs with data types. I would add a new ctype for each
> >   unit/selector pair [...]
> > - I don't have a preference between explicit control names and the
> >   basename/suffix system the EVO driver currently uses. If you prefer
> >   we can simply replace the basename with a full name and remove the
> >   flags field in the controls.
> 
> Yes, full names would make the iD14 table easier to check. And
> one ctype per unit/selector pair is fine with me.

ok, see patch 2 for the names and patch 3 to make the unit/selector pairs
more explicit.

> > - The boost switch writing 0x0 for 0dB gain and 0x0a00 for 10dB gain
> >   looks suspiciously like a volume control between 0dB and 10dB *
> >   256steps/dB. Does this control only accept these two values or can
> >   we simply implement it as a standard volume type controlling a mic
> >   pre-amp?
> 
> Your guess was correct! The device answers no RANGE request for it, so
> I tried intermediate values with a loopback cable: 0x0100, 0x0280 and
> 0x0500 gave +1, +2.5 and +5 dB on both mic inputs, each tested
> successfully within 0.01 dB of nominal. I didn't test outside 0..+10 dB
> though.
> 
> Even so, I'd like to keep it as a switch in this series, because the
> iD14's documentation describes a fixed +10 dB boost. Your max-for-true,
> min-for-false boolean would fit that, with 0 and 0x0a00. A 0..10 dB
> volume could follow as its own patch if people want it later. Does that
> sound reasonable?

OK, with the current implementation both should be possible with a simple
table change.

> [...]
> I haven't tested whether the iD14 rejects them. Could the generic put
> handlers reject values outside each control's writable ALSA range with
> -EINVAL, before converting them to device values? That would cover
> both devices.

OK, see patch 7.

> [...]

Christian Ruppert (11):
  ALSA: rename mixer_evo to mixer_audient
  ALSA: mixer_audient: explicitly define full control names
  ALSA: mixer_audient: clarify USB control message definition
  ALSA: mixer_audient: Add length check to USB transfer
  ALSA: mixer_audient: make USB control transfer size configurable
  ALSA: mixer_audient: Allow arbitrary boolean control values
  ALSA: mixer_audient: Add integer range checks
  ALSA: mixer_audient: Add control initialization at probe
  ALSA: mixer_audient: Add readback-free parameter set
  ALSA: mixer_audient: add control value caching
  ALSA: mixer_audient: Create matrix programmatically

 MAINTAINERS               |   7 +-
 sound/usb/Makefile        |   2 +-
 sound/usb/mixer_audient.c | 633 ++++++++++++++++++++++++++++++++++++++
 sound/usb/mixer_audient.h |  12 +
 sound/usb/mixer_evo.c     | 526 -------------------------------
 sound/usb/mixer_evo.h     |  12 -
 sound/usb/mixer_quirks.c  |   4 +-
 7 files changed, 652 insertions(+), 544 deletions(-)
 create mode 100644 sound/usb/mixer_audient.c
 create mode 100644 sound/usb/mixer_audient.h
 delete mode 100644 sound/usb/mixer_evo.c
 delete mode 100644 sound/usb/mixer_evo.h

-- 
2.56.0

[RFC PATCH 01/11] ALSA: rename mixer_evo to mixer_audient

[Christian Ruppert]

Rename mixer_evo files and functions to *_audient in preparation of a more
generic driver for audient devices.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 MAINTAINERS                                |   7 +-
 sound/usb/Makefile                         |   2 +-
 sound/usb/{mixer_evo.c => mixer_audient.c} | 247 +++++++++++----------
 sound/usb/mixer_audient.h                  |  12 +
 sound/usb/mixer_evo.h                      |  12 -
 sound/usb/mixer_quirks.c                   |   4 +-
 6 files changed, 147 insertions(+), 137 deletions(-)
 rename sound/usb/{mixer_evo.c => mixer_audient.c} (54%)
 create mode 100644 sound/usb/mixer_audient.h
 delete mode 100644 sound/usb/mixer_evo.h

diff --git a/MAINTAINERS b/MAINTAINERS
index fee9d090b280..a1139ae3404d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4354,12 +4354,13 @@ F:	drivers/net/ieee802154/at86rf230.h
 F:	drivers/net/ieee802154/atusb.c
 F:	drivers/net/ieee802154/atusb.h
 
-AUDIENT EVO MIXER DRIVER
+AUDIENT MIXER DRIVER
 M:	Christian Ruppert <arc@gmx.li>
+M:	Will Porter <mrwillporter@gmail.com>
 L:	linux-sound@vger.kernel.org
 S:	Maintained
-F:	sound/usb/mixer_evo.c
-F:	sound/usb/mixer_evo.h
+F:	sound/usb/mixer_audient.c
+F:	sound/usb/mixer_audient.h
 
 AUDIT SUBSYSTEM
 M:	Paul Moore <paul@paul-moore.com>
diff --git a/sound/usb/Makefile b/sound/usb/Makefile
index 2e842dcc73de..44f4e4c820fb 100644
--- a/sound/usb/Makefile
+++ b/sound/usb/Makefile
@@ -11,7 +11,7 @@ snd-usb-audio-y := 	card.o \
 			helper.o \
 			implicit.o \
 			mixer.o \
-			mixer_evo.o \
+			mixer_audient.o \
 			mixer_quirks.o \
 			mixer_scarlett.o \
 			mixer_scarlett2.o \
diff --git a/sound/usb/mixer_evo.c b/sound/usb/mixer_audient.c
similarity index 54%
rename from sound/usb/mixer_evo.c
rename to sound/usb/mixer_audient.c
index c1e0332232f2..8c1524c9b165 100644
--- a/sound/usb/mixer_evo.c
+++ b/sound/usb/mixer_audient.c
@@ -3,7 +3,7 @@
  * Audient EVO driver for ALSA
  * Copyright (C) 2026 Christian Ruppert <arc@gmx.li>
  *
- * Based on the work of Ivan Hazucha for audient-evo-py.
+ * EVO4 support is based on the work of Ivan Hazucha for audient-evo-py.
  * https://github.com/vanzaho/audient-evo-py/
  */
 
@@ -20,22 +20,22 @@
 #include "mixer.h"
 #include "mixer_quirks.h"
 #include "helper.h"
-#include "mixer_evo.h"
+#include "mixer_audient.h"
 
 
-enum snd_evo_type {
-	SND_EVO_TYPE_MONITOR = 0,
-	SND_EVO_TYPE_PHANTOM,
-	SND_EVO_TYPE_MUTE,
-	SND_EVO_TYPE_MUTE_OUT,
-	SND_EVO_TYPE_MIXER,
-	SND_EVO_TYPE_NCTYPES
+enum snd_audient_type {
+	SND_AUDIENT_TYPE_MONITOR = 0,
+	SND_AUDIENT_TYPE_PHANTOM,
+	SND_AUDIENT_TYPE_MUTE,
+	SND_AUDIENT_TYPE_MUTE_OUT,
+	SND_AUDIENT_TYPE_MIXER,
+	SND_AUDIENT_TYPE_NCTYPES
 };
 
 /* Mixer matrix: -128dB (mute) to +6dB */
-static const DECLARE_TLV_DB_MINMAX_MUTE(snd_evo_tlv_mixer, -12800, 600);
+static const DECLARE_TLV_DB_MINMAX_MUTE(snd_audient_tlv_mixer, -12800, 600);
 
-static const struct snd_evo_ctrl_type {
+static const struct snd_audient_ctrl_type {
 	snd_ctl_elem_type_t type;
 	bool invert;
 	union {
@@ -47,8 +47,8 @@ static const struct snd_evo_ctrl_type {
 	const unsigned int *tlv;
 	u16 wValue;
 	u16 wIndex;
-} snd_evo_ctypes[SND_EVO_TYPE_NCTYPES] = {
-	[SND_EVO_TYPE_MONITOR] = {
+} snd_audient_ctypes[SND_AUDIENT_TYPE_NCTYPES] = {
+	[SND_AUDIENT_TYPE_MONITOR] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
 		.min.integer = 0,
 		.max.integer = 127,
@@ -56,7 +56,7 @@ static const struct snd_evo_ctrl_type {
 		.wIndex = 0x3800,
 		/* no TLV here because we can't describe the cross-fader */
 	},
-	[SND_EVO_TYPE_PHANTOM] = {
+	[SND_AUDIENT_TYPE_PHANTOM] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = false,
 		.min.integer = 0,
@@ -64,7 +64,7 @@ static const struct snd_evo_ctrl_type {
 		.wValue = 0x0000,
 		.wIndex = 0x3A00,
 	},
-	[SND_EVO_TYPE_MUTE] = {
+	[SND_AUDIENT_TYPE_MUTE] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = true,
 		.min.integer = 0,
@@ -72,7 +72,7 @@ static const struct snd_evo_ctrl_type {
 		.wValue = 0x0200,
 		.wIndex = 0x3A00,
 	},
-	[SND_EVO_TYPE_MUTE_OUT] = {
+	[SND_AUDIENT_TYPE_MUTE_OUT] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = true,
 		.min.integer = 0,
@@ -80,135 +80,135 @@ static const struct snd_evo_ctrl_type {
 		.wValue = 0x0100,
 		.wIndex = 0x3B00,
 	},
-	[SND_EVO_TYPE_MIXER] = {
+	[SND_AUDIENT_TYPE_MIXER] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
 		.min.integer = -128 * 256,
 		.max.integer = 6 * 256,
 		.wValue = 0x0100,
 		.wIndex = 0x3C00,
-		.tlv = snd_evo_tlv_mixer,
+		.tlv = snd_audient_tlv_mixer,
 	},
 };
 
-#define SND_EVO_FLAGS_DIRECTION (1L<<0)
-#define SND_EVO_FLAGS_CAPTURE (1L<<0)
-#define SND_EVO_FLAGS_PLAYBACK (0L<<0)
+#define SND_AUDIENT_FLAGS_DIRECTION (1L<<0)
+#define SND_AUDIENT_FLAGS_CAPTURE (1L<<0)
+#define SND_AUDIENT_FLAGS_PLAYBACK (0L<<0)
 
-struct snd_evo_ctrl {
+struct snd_audient_ctrl {
 	char *basename;
-	enum snd_evo_type type;
+	enum snd_audient_type type;
 	unsigned int channels;
 	unsigned int hwchannels;
 	unsigned int val_offs;
 	unsigned long flags;
 };
 
-static const struct snd_evo_ctrl evo4_controls[] = {
+static const struct snd_audient_ctrl snd_audient_evo4_controls[] = {
 	{
 		.basename = "Master",
-		.type = SND_EVO_TYPE_MUTE_OUT,
+		.type = SND_AUDIENT_TYPE_MUTE_OUT,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 0,
-		.flags = SND_EVO_FLAGS_PLAYBACK,
+		.flags = SND_AUDIENT_FLAGS_PLAYBACK,
 	},
 	{
 		.basename = "Mic",
-		.type = SND_EVO_TYPE_MUTE,
+		.type = SND_AUDIENT_TYPE_MUTE,
 		.channels = 4,
 		.hwchannels = 2,
 		.val_offs = 0,
-		.flags = SND_EVO_FLAGS_PLAYBACK,
+		.flags = SND_AUDIENT_FLAGS_PLAYBACK,
 	},
 	{
 		.basename = "Monitor",
-		.type = SND_EVO_TYPE_MONITOR,
+		.type = SND_AUDIENT_TYPE_MONITOR,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 0,
-		.flags = SND_EVO_FLAGS_PLAYBACK,
+		.flags = SND_AUDIENT_FLAGS_PLAYBACK,
 	},
 	{
 		.basename = "Mic 1",
-		.type = SND_EVO_TYPE_MIXER,
+		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 0,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
 		.basename = "Mic 2",
-		.type = SND_EVO_TYPE_MIXER,
+		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 2,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
 		.basename = "Master Left",
-		.type = SND_EVO_TYPE_MIXER,
+		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 4,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
 		.basename = "Master Right",
-		.type = SND_EVO_TYPE_MIXER,
+		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 6,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
 		.basename = "Loopback Left",
-		.type = SND_EVO_TYPE_MIXER,
+		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 8,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
 		.basename = "Loopback Right",
-		.type = SND_EVO_TYPE_MIXER,
+		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 10,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
 		.basename = "Mic 1 Phantom",
-		.type = SND_EVO_TYPE_PHANTOM,
+		.type = SND_AUDIENT_TYPE_PHANTOM,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 0,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
 		.basename = "Mic 2 Phantom",
-		.type = SND_EVO_TYPE_PHANTOM,
+		.type = SND_AUDIENT_TYPE_PHANTOM,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 1,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{ 0 }, /* sentinel */
 };
 
-static const struct evo_devinfo {
+static const struct audient_devinfo {
 	u32 usb_id;
-	const struct snd_evo_ctrl *controls;
-} evo_devinfo[] = {
+	const struct snd_audient_ctrl *controls;
+} audient_devinfo[] = {
 	{
 		.usb_id = USB_ID(USB_AUDIENT_VID, USB_EVO4_PID),
-		.controls = evo4_controls,
+		.controls = snd_audient_evo4_controls,
 	},
 	{ 0 } /* sentinel */
 };
 
 
-static inline unsigned long snd_evo_kctl_priv(enum snd_evo_type type,
-					      u8 valoffs, u8 hwchannels)
+static inline unsigned long snd_audient_kctl_priv(enum snd_audient_type type,
+						  u8 valoffs, u8 hwchannels)
 {
 	unsigned long type_l = type & 0xFF;
 	unsigned long valoffs_l = valoffs & 0xFF;
@@ -218,22 +218,24 @@ static inline unsigned long snd_evo_kctl_priv(enum snd_evo_type type,
 }
 
 static __always_inline
-const struct snd_evo_ctrl_type *snd_evo_kctl_type(struct snd_kcontrol *kctl)
+const struct snd_audient_ctrl_type *snd_audient_kctl_type(struct snd_kcontrol
+							  *kctl)
 {
-	return &snd_evo_ctypes[kctl->private_value & 0xFF];
+	return &snd_audient_ctypes[kctl->private_value & 0xFF];
 }
 
-static __always_inline u16 snd_evo_kctl_valoffs(struct snd_kcontrol *kctl)
+static __always_inline u16 snd_audient_kctl_valoffs(struct snd_kcontrol *kctl)
 {
 	return (kctl->private_value >> 8) & 0xFF;
 }
 
-static __always_inline u16 snd_evo_kctl_hwchannels(struct snd_kcontrol *kctl)
+static __always_inline
+u16 snd_audient_kctl_hwchannels(struct snd_kcontrol *kctl)
 {
 	return (kctl->private_value >> 16) & 0xFF;
 }
 
-static inline u16 snd_evo_kctl_channels(struct snd_kcontrol *kctl)
+static inline u16 snd_audient_kctl_channels(struct snd_kcontrol *kctl)
 {
 	struct usb_mixer_elem_info *info = kctl->private_data;
 
@@ -241,43 +243,45 @@ static inline u16 snd_evo_kctl_channels(struct snd_kcontrol *kctl)
 }
 
 
-#define EVO_REQ_CUR (0x01)
-#define EVO_REQTYPE_SET (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE)
-#define EVO_REQTYPE_GET (USB_DIR_IN  | USB_TYPE_CLASS | USB_RECIP_INTERFACE)
+#define AUDIENT_REQTYPE_SET (USB_DIR_OUT | USB_TYPE_CLASS \
+					 | USB_RECIP_INTERFACE)
+#define AUDIENT_REQTYPE_GET (USB_DIR_IN  | USB_TYPE_CLASS \
+					 | USB_RECIP_INTERFACE)
 
-static inline int snd_evo_get_cur(struct usb_mixer_interface *mixer,
-				  u16 value, u16 index,
-				  void *buf, size_t len)
+static inline int snd_audient_get_cur(struct usb_mixer_interface *mixer,
+				      u16 value, u16 index,
+				      void *buf, size_t len)
 {
 	struct usb_device *const dev = mixer->chip->dev;
 
 	return snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
-			       EVO_REQ_CUR, EVO_REQTYPE_GET,
+			       UAC2_CS_CUR, AUDIENT_REQTYPE_GET,
 			       value, index, buf, len);
 }
 
-static inline int snd_evo_set_cur(struct usb_mixer_interface *mixer,
-				  u16 value, u16 index,
-				  void *buf, size_t len)
+static inline int snd_audient_set_cur(struct usb_mixer_interface *mixer,
+				      u16 value, u16 index,
+				      void *buf, size_t len)
 {
 	struct usb_device *const dev = mixer->chip->dev;
 
 	return snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0),
-			       EVO_REQ_CUR, EVO_REQTYPE_SET,
+			       UAC2_CS_CUR, AUDIENT_REQTYPE_SET,
 			       value, index, buf, len);
 }
 
 
-static int snd_ctl_evo_boolean_get(struct snd_kcontrol *kctl,
-				   struct snd_ctl_elem_value *ctl_val)
+static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
+				       struct snd_ctl_elem_value *ctl_val)
 {
 	struct usb_mixer_elem_list *const list = snd_kcontrol_chip(kctl);
 	struct usb_mixer_interface *const mixer = list->mixer;
 
-	const unsigned int nchan = snd_evo_kctl_channels(kctl);
-	const unsigned int hwchan = snd_evo_kctl_hwchannels(kctl);
-	const struct snd_evo_ctrl_type *const ctype = snd_evo_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_evo_kctl_valoffs(kctl);
+	const unsigned int nchan = snd_audient_kctl_channels(kctl);
+	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
+	const struct snd_audient_ctrl_type *const ctype
+						= snd_audient_kctl_type(kctl);
+	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
 	const u16 index = ctype->wIndex;
 
 	int i;
@@ -290,8 +294,8 @@ static int snd_ctl_evo_boolean_get(struct snd_kcontrol *kctl,
 		u32 buf;
 		int ret;
 
-		ret = snd_evo_get_cur(mixer, value + i, index,
-				      &buf, sizeof(buf));
+		ret = snd_audient_get_cur(mixer, value + i, index,
+					  &buf, sizeof(buf));
 		if (ret < 0)
 			return ret;
 
@@ -309,15 +313,16 @@ static int snd_ctl_evo_boolean_get(struct snd_kcontrol *kctl,
 	return 0;
 }
 
-static int snd_ctl_evo_boolean_set(struct snd_kcontrol *kctl,
-				   struct snd_ctl_elem_value *ctl_val)
+static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
+				       struct snd_ctl_elem_value *ctl_val)
 {
 	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kctl);
 	struct usb_mixer_interface *mixer = list->mixer;
 
-	const unsigned int hwchan = snd_evo_kctl_hwchannels(kctl);
-	const struct snd_evo_ctrl_type *const ctype = snd_evo_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_evo_kctl_valoffs(kctl);
+	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
+	const struct snd_audient_ctrl_type *const ctype
+						= snd_audient_kctl_type(kctl);
+	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
 	const u16 index = ctype->wIndex;
 
 	int changed = 0;
@@ -335,7 +340,7 @@ static int snd_ctl_evo_boolean_set(struct snd_kcontrol *kctl,
 		if (ctype->invert)
 			buf ^= cpu_to_le32(0x1);
 
-		ret = snd_evo_get_cur(mixer, value + i, index,
+		ret = snd_audient_get_cur(mixer, value + i, index,
 				      &rbuf, sizeof(rbuf));
 		if (ret < 0)
 			return ret;
@@ -343,8 +348,8 @@ static int snd_ctl_evo_boolean_set(struct snd_kcontrol *kctl,
 		if (rbuf != buf) {
 			changed = 1;
 
-			ret = snd_evo_set_cur(mixer, value + i, index,
-					      &buf, sizeof(buf));
+			ret = snd_audient_set_cur(mixer, value + i, index,
+						  &buf, sizeof(buf));
 			if (ret < 0)
 				return ret;
 		}
@@ -353,16 +358,17 @@ static int snd_ctl_evo_boolean_set(struct snd_kcontrol *kctl,
 	return changed;
 }
 
-static int snd_ctl_evo_integer_get(struct snd_kcontrol *kctl,
+static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 				   struct snd_ctl_elem_value *ctl_val)
 {
 	struct usb_mixer_elem_list *const list = snd_kcontrol_chip(kctl);
 	struct usb_mixer_interface *const mixer = list->mixer;
 
-	const unsigned int nchan = snd_evo_kctl_channels(kctl);
-	const unsigned int hwchan = snd_evo_kctl_hwchannels(kctl);
-	const struct snd_evo_ctrl_type *const ctype = snd_evo_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_evo_kctl_valoffs(kctl);
+	const unsigned int nchan = snd_audient_kctl_channels(kctl);
+	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
+	const struct snd_audient_ctrl_type *const ctype
+						= snd_audient_kctl_type(kctl);
+	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
 	const u16 index = ctype->wIndex;
 
 	int i;
@@ -376,8 +382,8 @@ static int snd_ctl_evo_integer_get(struct snd_kcontrol *kctl,
 		s16 val;
 		int ret;
 
-		ret = snd_evo_get_cur(mixer, value + i, index,
-				      &buf, sizeof(buf));
+		ret = snd_audient_get_cur(mixer, value + i, index,
+					  &buf, sizeof(buf));
 		if (ret < 0)
 			return ret;
 
@@ -391,15 +397,16 @@ static int snd_ctl_evo_integer_get(struct snd_kcontrol *kctl,
 	return 0;
 }
 
-static int snd_ctl_evo_integer_set(struct snd_kcontrol *kctl,
+static int snd_ctl_audient_integer_set(struct snd_kcontrol *kctl,
 				   struct snd_ctl_elem_value *ctl_val)
 {
 	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kctl);
 	struct usb_mixer_interface *mixer = list->mixer;
 
-	const unsigned int hwchan = snd_evo_kctl_hwchannels(kctl);
-	const struct snd_evo_ctrl_type *const ctype = snd_evo_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_evo_kctl_valoffs(kctl);
+	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
+	const struct snd_audient_ctrl_type *const ctype
+						= snd_audient_kctl_type(kctl);
+	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
 	const u16 index = ctype->wIndex;
 
 	int changed = 0;
@@ -414,16 +421,16 @@ static int snd_ctl_evo_integer_set(struct snd_kcontrol *kctl,
 		s16 buf = cpu_to_le16(ctl_val->value.integer.value[i]);
 		int ret;
 
-		ret = snd_evo_get_cur(mixer, value + i, index,
-				      &rbuf, sizeof(rbuf));
+		ret = snd_audient_get_cur(mixer, value + i, index,
+					  &rbuf, sizeof(rbuf));
 		if (ret < 0)
 			return ret;
 
 		if (rbuf != buf) {
 			changed = 1;
 
-			ret = snd_evo_set_cur(mixer, value + i, index,
-					      &buf, sizeof(buf));
+			ret = snd_audient_set_cur(mixer, value + i, index,
+						  &buf, sizeof(buf));
 			if (ret < 0)
 				return ret;
 		}
@@ -432,23 +439,25 @@ static int snd_ctl_evo_integer_set(struct snd_kcontrol *kctl,
 	return changed;
 }
 
-static int snd_ctl_evo_info(struct snd_kcontrol *kctl,
+static int snd_ctl_audient_info(struct snd_kcontrol *kctl,
 			    struct snd_ctl_elem_info *uinfo)
 {
-	const struct snd_evo_ctrl_type *const ctype = snd_evo_kctl_type(kctl);
+	const struct snd_audient_ctrl_type *const ctype
+						= snd_audient_kctl_type(kctl);
 
 	uinfo->type = ctype->type;
-	uinfo->count = snd_evo_kctl_channels(kctl);
+	uinfo->count = snd_audient_kctl_channels(kctl);
 	uinfo->value.integer.min = ctype->min.integer;
 	uinfo->value.integer.max = ctype->max.integer;
 	return 0;
 }
 
 
-static int snd_evo_add_ctrl(struct usb_mixer_interface *mixer,
-			    const struct snd_evo_ctrl *ctrl)
+static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
+			    const struct snd_audient_ctrl *ctrl)
 {
-	const struct snd_evo_ctrl_type *ctype = &snd_evo_ctypes[ctrl->type];
+	const struct snd_audient_ctrl_type *ctype
+					= &snd_audient_ctypes[ctrl->type];
 	char name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
 	struct snd_kcontrol_new knew = { 0 };
 	struct snd_kcontrol *kctl;
@@ -456,9 +465,9 @@ static int snd_evo_add_ctrl(struct usb_mixer_interface *mixer,
 
 	knew.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
 	knew.name = name;
-	knew.info = snd_ctl_evo_info;
-	knew.private_value = snd_evo_kctl_priv(ctrl->type, ctrl->val_offs,
-					       ctrl->hwchannels);
+	knew.info = snd_ctl_audient_info;
+	knew.private_value = snd_audient_kctl_priv(ctrl->type, ctrl->val_offs,
+						   ctrl->hwchannels);
 	knew.tlv.p = ctype->tlv;
 	knew.access = SNDRV_CTL_ELEM_ACCESS_READWRITE
 			| SNDRV_CTL_ELEM_ACCESS_VOLATILE
@@ -466,20 +475,20 @@ static int snd_evo_add_ctrl(struct usb_mixer_interface *mixer,
 
 	switch (ctype->type) {
 	case SNDRV_CTL_ELEM_TYPE_INTEGER:
-		knew.get = snd_ctl_evo_integer_get;
-		knew.put = snd_ctl_evo_integer_set;
+		knew.get = snd_ctl_audient_integer_get;
+		knew.put = snd_ctl_audient_integer_set;
 		break;
 	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
-		knew.get = snd_ctl_evo_boolean_get;
-		knew.put = snd_ctl_evo_boolean_set;
+		knew.get = snd_ctl_audient_boolean_get;
+		knew.put = snd_ctl_audient_boolean_set;
 		break;
 	default:
 		return -EINVAL;
 	}
 
 	snprintf(name, sizeof(name), "%s %s %s", ctrl->basename,
-		 ((ctrl->flags & SND_EVO_FLAGS_DIRECTION)
-			== SND_EVO_FLAGS_CAPTURE) ? "Capture" : "Playback",
+		 ((ctrl->flags & SND_AUDIENT_FLAGS_DIRECTION)
+			== SND_AUDIENT_FLAGS_CAPTURE) ? "Capture" : "Playback",
 		 (ctype->type == SNDRV_CTL_ELEM_TYPE_BOOLEAN)
 			? "Switch" : "Volume");
 
@@ -503,12 +512,12 @@ static int snd_evo_add_ctrl(struct usb_mixer_interface *mixer,
 
 
 /* called from mixer_quirks.c */
-int snd_evo_controls_create(struct usb_mixer_interface *mixer)
+int snd_audient_controls_create(struct usb_mixer_interface *mixer)
 {
-	const struct evo_devinfo *info;
-	const struct snd_evo_ctrl *ctrl;
+	const struct audient_devinfo *info;
+	const struct snd_audient_ctrl *ctrl;
 
-	for (info = evo_devinfo; info->controls; info++)
+	for (info = audient_devinfo; info->controls; info++)
 		if (info->usb_id == mixer->chip->usb_id)
 			break;
 
@@ -516,7 +525,7 @@ int snd_evo_controls_create(struct usb_mixer_interface *mixer)
 		return -ENODEV;
 
 	for (ctrl = info->controls; ctrl->basename; ctrl++) {
-		const int ret = snd_evo_add_ctrl(mixer, ctrl);
+		const int ret = snd_audient_add_ctrl(mixer, ctrl);
 
 		if (ret < 0)
 			return ret;
diff --git a/sound/usb/mixer_audient.h b/sound/usb/mixer_audient.h
new file mode 100644
index 000000000000..db4f31e02b5e
--- /dev/null
+++ b/sound/usb/mixer_audient.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __USB_MIXER_AUDIENT_H
+#define __USB_MIXER_AUDIENT_H
+
+#include "mixer.h"
+
+#define USB_AUDIENT_VID (0x2708)
+#define USB_EVO4_PID (0x0006)
+
+int snd_audient_controls_create(struct usb_mixer_interface *mixer);
+
+#endif /* __USB_MIXER_AUDIENT_H */
diff --git a/sound/usb/mixer_evo.h b/sound/usb/mixer_evo.h
deleted file mode 100644
index 7fe7e197185c..000000000000
--- a/sound/usb/mixer_evo.h
+++ /dev/null
@@ -1,12 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __USB_MIXER_EVO_H
-#define __USB_MIXER_EVO_H
-
-#include "mixer.h"
-
-#define USB_AUDIENT_VID (0x2708)
-#define USB_EVO4_PID (0x0006)
-
-int snd_evo_controls_create(struct usb_mixer_interface *mixer);
-
-#endif /* __USB_MIXER_EVO_H */
diff --git a/sound/usb/mixer_quirks.c b/sound/usb/mixer_quirks.c
index 01210cc3fae7..af53c5c20e65 100644
--- a/sound/usb/mixer_quirks.c
+++ b/sound/usb/mixer_quirks.c
@@ -38,7 +38,7 @@
 #include "mixer_scarlett2.h"
 #include "mixer_us16x08.h"
 #include "mixer_s1810c.h"
-#include "mixer_evo.h"
+#include "mixer_audient.h"
 #include "helper.h"
 #include "fcp.h"
 
@@ -4541,7 +4541,7 @@ int snd_usb_mixer_apply_create_quirk(struct usb_mixer_interface *mixer)
 		break;
 
 	case USB_ID(USB_AUDIENT_VID, USB_EVO4_PID): /* Audient EVO 4 */
-		err = snd_evo_controls_create(mixer);
+		err = snd_audient_controls_create(mixer);
 		break;
 
 	case USB_ID(0x041e, 0x323b): /* Creative Sound Blaster E1 */
-- 
2.56.0

[RFC PATCH 02/11] ALSA: mixer_audient: explicitly define full control names

[Christian Ruppert]

Previously, control names were dynamically created depending if the
control was an input or an output, a volume or a switch. Get rid of this
logic by simply defining the full name in the control structure.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 50 +++++++++++----------------------------
 1 file changed, 14 insertions(+), 36 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 8c1524c9b165..917b5bc53869 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -90,107 +90,92 @@ static const struct snd_audient_ctrl_type {
 	},
 };
 
-#define SND_AUDIENT_FLAGS_DIRECTION (1L<<0)
-#define SND_AUDIENT_FLAGS_CAPTURE (1L<<0)
-#define SND_AUDIENT_FLAGS_PLAYBACK (0L<<0)
 
 struct snd_audient_ctrl {
-	char *basename;
+	char *name;
 	enum snd_audient_type type;
 	unsigned int channels;
 	unsigned int hwchannels;
 	unsigned int val_offs;
-	unsigned long flags;
 };
 
 static const struct snd_audient_ctrl snd_audient_evo4_controls[] = {
 	{
-		.basename = "Master",
+		.name = "Master Playback Switch",
 		.type = SND_AUDIENT_TYPE_MUTE_OUT,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 0,
-		.flags = SND_AUDIENT_FLAGS_PLAYBACK,
 	},
 	{
-		.basename = "Mic",
+		.name = "Mic Playback Switch",
 		.type = SND_AUDIENT_TYPE_MUTE,
 		.channels = 4,
 		.hwchannels = 2,
 		.val_offs = 0,
-		.flags = SND_AUDIENT_FLAGS_PLAYBACK,
 	},
 	{
-		.basename = "Monitor",
+		.name = "Monitor Playback Volume",
 		.type = SND_AUDIENT_TYPE_MONITOR,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 0,
-		.flags = SND_AUDIENT_FLAGS_PLAYBACK,
 	},
 	{
-		.basename = "Mic 1",
+		.name = "Mic 1 Capture Volume",
 		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 0,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
-		.basename = "Mic 2",
+		.name = "Mic 2 Capture Volume",
 		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 2,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
-		.basename = "Master Left",
+		.name = "Master Left Capture Volume",
 		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 4,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
-		.basename = "Master Right",
+		.name = "Master Right Capture Volume",
 		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 6,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
-		.basename = "Loopback Left",
+		.name = "Loopback Left Capture Volume",
 		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 8,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
-		.basename = "Loopback Right",
+		.name = "Loopback Right Capture Volume",
 		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 10,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
-		.basename = "Mic 1 Phantom",
+		.name = "Mic 1 Phantom Capture Switch",
 		.type = SND_AUDIENT_TYPE_PHANTOM,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 0,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
-		.basename = "Mic 2 Phantom",
+		.name = "Mic 2 Phantom Capture Switch",
 		.type = SND_AUDIENT_TYPE_PHANTOM,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 1,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{ 0 }, /* sentinel */
 };
@@ -458,13 +443,12 @@ static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
 {
 	const struct snd_audient_ctrl_type *ctype
 					= &snd_audient_ctypes[ctrl->type];
-	char name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
 	struct snd_kcontrol_new knew = { 0 };
 	struct snd_kcontrol *kctl;
 	struct usb_mixer_elem_info *elem;
 
 	knew.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
-	knew.name = name;
+	knew.name = ctrl->name;
 	knew.info = snd_ctl_audient_info;
 	knew.private_value = snd_audient_kctl_priv(ctrl->type, ctrl->val_offs,
 						   ctrl->hwchannels);
@@ -486,12 +470,6 @@ static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
 		return -EINVAL;
 	}
 
-	snprintf(name, sizeof(name), "%s %s %s", ctrl->basename,
-		 ((ctrl->flags & SND_AUDIENT_FLAGS_DIRECTION)
-			== SND_AUDIENT_FLAGS_CAPTURE) ? "Capture" : "Playback",
-		 (ctype->type == SNDRV_CTL_ELEM_TYPE_BOOLEAN)
-			? "Switch" : "Volume");
-
 	elem = kzalloc_obj(*elem);
 	if (!elem)
 		return -ENOMEM;
@@ -524,7 +502,7 @@ int snd_audient_controls_create(struct usb_mixer_interface *mixer)
 	if (!info->controls)
 		return -ENODEV;
 
-	for (ctrl = info->controls; ctrl->basename; ctrl++) {
+	for (ctrl = info->controls; ctrl->name; ctrl++) {
 		const int ret = snd_audient_add_ctrl(mixer, ctrl);
 
 		if (ret < 0)
-- 
2.56.0

[RFC PATCH 03/11] ALSA: mixer_audient: clarify USB control message definition

[Christian Ruppert]

Previously, base values for wIndex and wValue were directly given in the
control type. Construct them from a unit ID and selector for clarity.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 76 +++++++++++++++++++++------------------
 1 file changed, 41 insertions(+), 35 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 917b5bc53869..82591c32140f 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -45,15 +45,15 @@ static const struct snd_audient_ctrl_type {
 		int integer;
 	} max;
 	const unsigned int *tlv;
-	u16 wValue;
-	u16 wIndex;
+	u8 unit;
+	u8 sel;
 } snd_audient_ctypes[SND_AUDIENT_TYPE_NCTYPES] = {
 	[SND_AUDIENT_TYPE_MONITOR] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
 		.min.integer = 0,
 		.max.integer = 127,
-		.wValue = 0x0000,
-		.wIndex = 0x3800,
+		.unit = 0x38,
+		.sel = 0x00,
 		/* no TLV here because we can't describe the cross-fader */
 	},
 	[SND_AUDIENT_TYPE_PHANTOM] = {
@@ -61,31 +61,31 @@ static const struct snd_audient_ctrl_type {
 		.invert = false,
 		.min.integer = 0,
 		.max.integer = 1,
-		.wValue = 0x0000,
-		.wIndex = 0x3A00,
+		.unit = 0x3A,
+		.sel = 0x00,
 	},
 	[SND_AUDIENT_TYPE_MUTE] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = true,
 		.min.integer = 0,
 		.max.integer = 1,
-		.wValue = 0x0200,
-		.wIndex = 0x3A00,
+		.unit = 0x3A,
+		.sel = 0x02,
 	},
 	[SND_AUDIENT_TYPE_MUTE_OUT] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = true,
 		.min.integer = 0,
 		.max.integer = 1,
-		.wValue = 0x0100,
-		.wIndex = 0x3B00,
+		.unit = 0x3B,
+		.sel = 0x01,
 	},
 	[SND_AUDIENT_TYPE_MIXER] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
 		.min.integer = -128 * 256,
 		.max.integer = 6 * 256,
-		.wValue = 0x0100,
-		.wIndex = 0x3C00,
+		.unit = 0x3C,
+		.sel = 0x01,
 		.tlv = snd_audient_tlv_mixer,
 	},
 };
@@ -209,7 +209,7 @@ const struct snd_audient_ctrl_type *snd_audient_kctl_type(struct snd_kcontrol
 	return &snd_audient_ctypes[kctl->private_value & 0xFF];
 }
 
-static __always_inline u16 snd_audient_kctl_valoffs(struct snd_kcontrol *kctl)
+static __always_inline u16 snd_audient_kctl_cidxoffs(struct snd_kcontrol *kctl)
 {
 	return (kctl->private_value >> 8) & 0xFF;
 }
@@ -233,11 +233,16 @@ static inline u16 snd_audient_kctl_channels(struct snd_kcontrol *kctl)
 #define AUDIENT_REQTYPE_GET (USB_DIR_IN  | USB_TYPE_CLASS \
 					 | USB_RECIP_INTERFACE)
 
+#define U8_U8(HI, LO) ((((u16)(HI)) << 8) | ((LO) & 0xFF))
+
 static inline int snd_audient_get_cur(struct usb_mixer_interface *mixer,
-				      u16 value, u16 index,
-				      void *buf, size_t len)
+				      const u8 unit, const u8 sel,
+				      const u8 cidx,
+				      void *const buf, const size_t len)
 {
 	struct usb_device *const dev = mixer->chip->dev;
+	const u16 value = U8_U8(sel, cidx);
+	const u16 index = U8_U8(unit, mixer->hostif->desc.bInterfaceNumber);
 
 	return snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
 			       UAC2_CS_CUR, AUDIENT_REQTYPE_GET,
@@ -245,10 +250,13 @@ static inline int snd_audient_get_cur(struct usb_mixer_interface *mixer,
 }
 
 static inline int snd_audient_set_cur(struct usb_mixer_interface *mixer,
-				      u16 value, u16 index,
-				      void *buf, size_t len)
+				      const u8 unit, const u8 sel,
+				      const u8 cidx,
+				      void *const buf, const size_t len)
 {
 	struct usb_device *const dev = mixer->chip->dev;
+	const u16 value = U8_U8(sel, cidx);
+	const u16 index = U8_U8(unit, mixer->hostif->desc.bInterfaceNumber);
 
 	return snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0),
 			       UAC2_CS_CUR, AUDIENT_REQTYPE_SET,
@@ -266,8 +274,7 @@ static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
 	const struct snd_audient_ctrl_type *const ctype
 						= snd_audient_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
-	const u16 index = ctype->wIndex;
+	const u8 base = snd_audient_kctl_cidxoffs(kctl);
 
 	int i;
 
@@ -279,8 +286,8 @@ static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 		u32 buf;
 		int ret;
 
-		ret = snd_audient_get_cur(mixer, value + i, index,
-					  &buf, sizeof(buf));
+		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
+					  base + i, &buf, sizeof(buf));
 		if (ret < 0)
 			return ret;
 
@@ -307,8 +314,7 @@ static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
 	const struct snd_audient_ctrl_type *const ctype
 						= snd_audient_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
-	const u16 index = ctype->wIndex;
+	const u8 base = snd_audient_kctl_cidxoffs(kctl);
 
 	int changed = 0;
 	int i;
@@ -325,15 +331,16 @@ static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
 		if (ctype->invert)
 			buf ^= cpu_to_le32(0x1);
 
-		ret = snd_audient_get_cur(mixer, value + i, index,
-				      &rbuf, sizeof(rbuf));
+		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
+					  base + i, &rbuf, sizeof(rbuf));
 		if (ret < 0)
 			return ret;
 
 		if (rbuf != buf) {
 			changed = 1;
 
-			ret = snd_audient_set_cur(mixer, value + i, index,
+			ret = snd_audient_set_cur(mixer, ctype->unit,
+						  ctype->sel, base + i,
 						  &buf, sizeof(buf));
 			if (ret < 0)
 				return ret;
@@ -353,8 +360,7 @@ static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
 	const struct snd_audient_ctrl_type *const ctype
 						= snd_audient_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
-	const u16 index = ctype->wIndex;
+	const u8 base = snd_audient_kctl_cidxoffs(kctl);
 
 	int i;
 
@@ -367,8 +373,8 @@ static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 		s16 val;
 		int ret;
 
-		ret = snd_audient_get_cur(mixer, value + i, index,
-					  &buf, sizeof(buf));
+		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
+					  base + i, &buf, sizeof(buf));
 		if (ret < 0)
 			return ret;
 
@@ -391,8 +397,7 @@ static int snd_ctl_audient_integer_set(struct snd_kcontrol *kctl,
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
 	const struct snd_audient_ctrl_type *const ctype
 						= snd_audient_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
-	const u16 index = ctype->wIndex;
+	const u8 base = snd_audient_kctl_cidxoffs(kctl);
 
 	int changed = 0;
 	int i;
@@ -406,15 +411,16 @@ static int snd_ctl_audient_integer_set(struct snd_kcontrol *kctl,
 		s16 buf = cpu_to_le16(ctl_val->value.integer.value[i]);
 		int ret;
 
-		ret = snd_audient_get_cur(mixer, value + i, index,
-					  &rbuf, sizeof(rbuf));
+		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
+					  base + i, &rbuf, sizeof(rbuf));
 		if (ret < 0)
 			return ret;
 
 		if (rbuf != buf) {
 			changed = 1;
 
-			ret = snd_audient_set_cur(mixer, value + i, index,
+			ret = snd_audient_set_cur(mixer, ctype->unit,
+						  ctype->sel, base + i,
 						  &buf, sizeof(buf));
 			if (ret < 0)
 				return ret;
-- 
2.56.0

[RFC PATCH 04/11] ALSA: mixer_audient: Add length check to USB transfer

[Christian Ruppert]

Check USB control transfers not only for errors but also for expected
length and return -EIO in case of error.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 82591c32140f..24d2f7a0bdc2 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -244,9 +244,14 @@ static inline int snd_audient_get_cur(struct usb_mixer_interface *mixer,
 	const u16 value = U8_U8(sel, cidx);
 	const u16 index = U8_U8(unit, mixer->hostif->desc.bInterfaceNumber);
 
-	return snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
-			       UAC2_CS_CUR, AUDIENT_REQTYPE_GET,
-			       value, index, buf, len);
+	const int ret = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
+					UAC2_CS_CUR, AUDIENT_REQTYPE_GET,
+					value, index, buf, len);
+
+	if ((ret >= 0) && (ret != len))
+		return -EIO;
+
+	return ret;
 }
 
 static inline int snd_audient_set_cur(struct usb_mixer_interface *mixer,
@@ -258,9 +263,14 @@ static inline int snd_audient_set_cur(struct usb_mixer_interface *mixer,
 	const u16 value = U8_U8(sel, cidx);
 	const u16 index = U8_U8(unit, mixer->hostif->desc.bInterfaceNumber);
 
-	return snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0),
-			       UAC2_CS_CUR, AUDIENT_REQTYPE_SET,
-			       value, index, buf, len);
+	const int ret = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0),
+					UAC2_CS_CUR, AUDIENT_REQTYPE_SET,
+					value, index, buf, len);
+
+	if ((ret >= 0) && (ret != len))
+		return -EIO;
+
+	return ret;
 }
 
 
-- 
2.56.0

[RFC PATCH 05/11] ALSA: mixer_audient: make USB control transfer size configurable

[Christian Ruppert]

Previously, the USB transfer size was hardcoded in the datatype get/set
functions. Make it configurable in the ctype structure in preparation of
new control types for the id14.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 130 ++++++++++++++++++++++++--------------
 1 file changed, 83 insertions(+), 47 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 24d2f7a0bdc2..1438cc192d34 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -35,8 +35,12 @@ enum snd_audient_type {
 /* Mixer matrix: -128dB (mute) to +6dB */
 static const DECLARE_TLV_DB_MINMAX_MUTE(snd_audient_tlv_mixer, -12800, 600);
 
+#define SND_AUDIENT_CTYPE_FLAGS_SIGNED		(1L <<  0)
+
 static const struct snd_audient_ctrl_type {
 	snd_ctl_elem_type_t type;
+	unsigned long flags;
+	size_t len;
 	bool invert;
 	union {
 		int integer;
@@ -50,6 +54,7 @@ static const struct snd_audient_ctrl_type {
 } snd_audient_ctypes[SND_AUDIENT_TYPE_NCTYPES] = {
 	[SND_AUDIENT_TYPE_MONITOR] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
+		.len = 2,
 		.min.integer = 0,
 		.max.integer = 127,
 		.unit = 0x38,
@@ -59,6 +64,7 @@ static const struct snd_audient_ctrl_type {
 	[SND_AUDIENT_TYPE_PHANTOM] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = false,
+		.len = 4,
 		.min.integer = 0,
 		.max.integer = 1,
 		.unit = 0x3A,
@@ -67,6 +73,7 @@ static const struct snd_audient_ctrl_type {
 	[SND_AUDIENT_TYPE_MUTE] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = true,
+		.len = 4,
 		.min.integer = 0,
 		.max.integer = 1,
 		.unit = 0x3A,
@@ -75,6 +82,7 @@ static const struct snd_audient_ctrl_type {
 	[SND_AUDIENT_TYPE_MUTE_OUT] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = true,
+		.len = 4,
 		.min.integer = 0,
 		.max.integer = 1,
 		.unit = 0x3B,
@@ -82,6 +90,8 @@ static const struct snd_audient_ctrl_type {
 	},
 	[SND_AUDIENT_TYPE_MIXER] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
+		.flags = SND_AUDIENT_CTYPE_FLAGS_SIGNED,
+		.len = 2,
 		.min.integer = -128 * 256,
 		.max.integer = 6 * 256,
 		.unit = 0x3C,
@@ -236,44 +246,92 @@ static inline u16 snd_audient_kctl_channels(struct snd_kcontrol *kctl)
 #define U8_U8(HI, LO) ((((u16)(HI)) << 8) | ((LO) & 0xFF))
 
 static inline int snd_audient_get_cur(struct usb_mixer_interface *mixer,
-				      const u8 unit, const u8 sel,
-				      const u8 cidx,
-				      void *const buf, const size_t len)
+			const struct snd_audient_ctrl_type *const ctype,
+			const u8 cidx, void *const buf)
 {
 	struct usb_device *const dev = mixer->chip->dev;
-	const u16 value = U8_U8(sel, cidx);
-	const u16 index = U8_U8(unit, mixer->hostif->desc.bInterfaceNumber);
+	const u16 value = U8_U8(ctype->sel, cidx);
+	const u16 index = U8_U8(ctype->unit,
+				mixer->hostif->desc.bInterfaceNumber);
 
 	const int ret = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
 					UAC2_CS_CUR, AUDIENT_REQTYPE_GET,
-					value, index, buf, len);
+					value, index, buf, ctype->len);
 
-	if ((ret >= 0) && (ret != len))
+	if ((ret >= 0) && (ret != ctype->len))
 		return -EIO;
 
 	return ret;
 }
 
 static inline int snd_audient_set_cur(struct usb_mixer_interface *mixer,
-				      const u8 unit, const u8 sel,
-				      const u8 cidx,
-				      void *const buf, const size_t len)
+			const struct snd_audient_ctrl_type *const ctype,
+			const u8 cidx, void *const buf)
 {
 	struct usb_device *const dev = mixer->chip->dev;
-	const u16 value = U8_U8(sel, cidx);
-	const u16 index = U8_U8(unit, mixer->hostif->desc.bInterfaceNumber);
+	const u16 value = U8_U8(ctype->sel, cidx);
+	const u16 index = U8_U8(ctype->unit,
+				mixer->hostif->desc.bInterfaceNumber);
 
 	const int ret = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0),
 					UAC2_CS_CUR, AUDIENT_REQTYPE_SET,
-					value, index, buf, len);
+					value, index, buf, ctype->len);
 
-	if ((ret >= 0) && (ret != len))
+	if ((ret >= 0) && (ret != ctype->len))
 		return -EIO;
 
 	return ret;
 }
 
 
+static int snd_audient_raw_get_one(struct usb_mixer_interface *const mixer,
+			const struct snd_audient_ctrl_type *const ctype,
+			const u8 cidx, u32 *const value)
+{
+	int ret;
+	s32 buf = 0;
+
+	ret = snd_audient_get_cur(mixer, ctype, cidx, &buf);
+	if (ret < 0)
+		return ret;
+
+	buf = le32_to_cpu(buf);
+
+	if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_SIGNED) {
+		const unsigned int sh = 32 - 8 * ctype->len;
+
+		buf = (buf << sh) >> sh;
+	}
+
+	*value = buf;
+
+	return ret;
+}
+
+static int snd_audient_raw_set_one(struct usb_mixer_interface *const mixer,
+			const struct snd_audient_ctrl_type *const ctype,
+			const u8 cidx, const u32 value)
+{
+	int ret;
+	u32 buf;
+
+	ret = snd_audient_raw_get_one(mixer, ctype, cidx, &buf);
+	if (ret < 0)
+		return ret;
+
+	if (buf != value) {
+		buf = cpu_to_le32(value);
+		ret = snd_audient_set_cur(mixer, ctype, cidx, &buf);
+		if (ret < 0)
+			return ret;
+
+		return 1;
+	}
+
+	return 0;
+}
+
+
 static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 				       struct snd_ctl_elem_value *ctl_val)
 {
@@ -296,12 +354,11 @@ static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 		u32 buf;
 		int ret;
 
-		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
-					  base + i, &buf, sizeof(buf));
+		ret = snd_audient_raw_get_one(mixer, ctype, base + i, &buf);
 		if (ret < 0)
 			return ret;
 
-		ctl_val->value.integer.value[i] = le32_to_cpu(buf) ? 1 : 0;
+		ctl_val->value.integer.value[i] = buf ? 1 : 0;
 
 		if (ctype->invert)
 			ctl_val->value.integer.value[i] ^= 0x1;
@@ -334,27 +391,18 @@ static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
 		return pm.err;
 
 	for (i = 0; i < hwchan; i++) {
-		u32 rbuf;
-		u32 buf = cpu_to_le32(ctl_val->value.integer.value[i] ? 1 : 0);
+		u32 buf = ctl_val->value.integer.value[i] ? 1 : 0;
 		int ret;
 
 		if (ctype->invert)
-			buf ^= cpu_to_le32(0x1);
+			buf ^= 0x1;
 
-		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
-					  base + i, &rbuf, sizeof(rbuf));
+		ret = snd_audient_raw_set_one(mixer, ctype, base + i, buf);
 		if (ret < 0)
 			return ret;
 
-		if (rbuf != buf) {
+		if (ret)
 			changed = 1;
-
-			ret = snd_audient_set_cur(mixer, ctype->unit,
-						  ctype->sel, base + i,
-						  &buf, sizeof(buf));
-			if (ret < 0)
-				return ret;
-		}
 	}
 
 	return changed;
@@ -379,16 +427,13 @@ static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 		return pm.err;
 
 	for (i = 0; i < hwchan; i++) {
-		u16 buf;
-		s16 val;
+		s32 val;
 		int ret;
 
-		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
-					  base + i, &buf, sizeof(buf));
+		ret = snd_audient_raw_get_one(mixer, ctype, base + i, &val);
 		if (ret < 0)
 			return ret;
 
-		val = le16_to_cpu(buf);
 		ctl_val->value.integer.value[i] = val;
 	}
 
@@ -417,24 +462,15 @@ static int snd_ctl_audient_integer_set(struct snd_kcontrol *kctl,
 		return pm.err;
 
 	for (i = 0; i < hwchan; i++) {
-		s16 rbuf;
-		s16 buf = cpu_to_le16(ctl_val->value.integer.value[i]);
+		s32 val = ctl_val->value.integer.value[i];
 		int ret;
 
-		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
-					  base + i, &rbuf, sizeof(rbuf));
+		ret = snd_audient_raw_set_one(mixer, ctype, base + i, val);
 		if (ret < 0)
 			return ret;
 
-		if (rbuf != buf) {
+		if (ret)
 			changed = 1;
-
-			ret = snd_audient_set_cur(mixer, ctype->unit,
-						  ctype->sel, base + i,
-						  &buf, sizeof(buf));
-			if (ret < 0)
-				return ret;
-		}
 	}
 
 	return changed;
-- 
2.56.0

[RFC PATCH 06/11] ALSA: mixer_audient: Allow arbitrary boolean control values

[Christian Ruppert]

In preparation of id14 support, allow arbitrary values for true and false
of boolean switches. This also rids us of the tedious invert flag.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 43 ++++++++++++++++++---------------------
 1 file changed, 20 insertions(+), 23 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 1438cc192d34..6352aee0fb5e 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -41,13 +41,12 @@ static const struct snd_audient_ctrl_type {
 	snd_ctl_elem_type_t type;
 	unsigned long flags;
 	size_t len;
-	bool invert;
 	union {
 		int integer;
-	} min;
+	} min;		/* for booleans holds physical int value for false */
 	union {
 		int integer;
-	} max;
+	} max;		/* for booleans holds physical int value for true */
 	const unsigned int *tlv;
 	u8 unit;
 	u8 sel;
@@ -63,7 +62,6 @@ static const struct snd_audient_ctrl_type {
 	},
 	[SND_AUDIENT_TYPE_PHANTOM] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
-		.invert = false,
 		.len = 4,
 		.min.integer = 0,
 		.max.integer = 1,
@@ -72,19 +70,17 @@ static const struct snd_audient_ctrl_type {
 	},
 	[SND_AUDIENT_TYPE_MUTE] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
-		.invert = true,
 		.len = 4,
-		.min.integer = 0,
-		.max.integer = 1,
+		.min.integer = 1,
+		.max.integer = 0,
 		.unit = 0x3A,
 		.sel = 0x02,
 	},
 	[SND_AUDIENT_TYPE_MUTE_OUT] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
-		.invert = true,
 		.len = 4,
-		.min.integer = 0,
-		.max.integer = 1,
+		.min.integer = 1,
+		.max.integer = 0,
 		.unit = 0x3B,
 		.sel = 0x01,
 	},
@@ -358,16 +354,12 @@ static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 		if (ret < 0)
 			return ret;
 
-		ctl_val->value.integer.value[i] = buf ? 1 : 0;
-
-		if (ctype->invert)
-			ctl_val->value.integer.value[i] ^= 0x1;
+		ctl_val->value.integer.value[i] = (buf == ctype->min.integer)
+						  ? false : true;
 	}
 
 	for (; i < nchan; i++)
-		ctl_val->value.integer.value[i] = ctype->invert
-							? ctype->max.integer
-							: ctype->min.integer;
+		ctl_val->value.integer.value[i] = 0;
 
 	return 0;
 }
@@ -391,12 +383,10 @@ static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
 		return pm.err;
 
 	for (i = 0; i < hwchan; i++) {
-		u32 buf = ctl_val->value.integer.value[i] ? 1 : 0;
+		u32 buf = ctl_val->value.integer.value[i] ? ctype->max.integer
+							  : ctype->min.integer;
 		int ret;
 
-		if (ctype->invert)
-			buf ^= 0x1;
-
 		ret = snd_audient_raw_set_one(mixer, ctype, base + i, buf);
 		if (ret < 0)
 			return ret;
@@ -484,8 +474,15 @@ static int snd_ctl_audient_info(struct snd_kcontrol *kctl,
 
 	uinfo->type = ctype->type;
 	uinfo->count = snd_audient_kctl_channels(kctl);
-	uinfo->value.integer.min = ctype->min.integer;
-	uinfo->value.integer.max = ctype->max.integer;
+
+	if (ctype->type == SNDRV_CTL_ELEM_TYPE_BOOLEAN) {
+		uinfo->value.integer.min = 0;
+		uinfo->value.integer.max = 1;
+	} else {
+		uinfo->value.integer.min = ctype->min.integer;
+		uinfo->value.integer.max = ctype->max.integer;
+	}
+
 	return 0;
 }
 
-- 
2.56.0

[RFC PATCH 07/11] ALSA: mixer_audient: Add integer range checks

[Christian Ruppert]

Add range checks to integer parameters to improve error management:
- Reject out-of-range write attempts with -EINVAL
- Prune out-of-range values returned by the device to the range limits

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 6352aee0fb5e..2f1b332859c9 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -42,10 +42,10 @@ static const struct snd_audient_ctrl_type {
 	unsigned long flags;
 	size_t len;
 	union {
-		int integer;
+		long integer;
 	} min;		/* for booleans holds physical int value for false */
 	union {
-		int integer;
+		long integer;
 	} max;		/* for booleans holds physical int value for true */
 	const unsigned int *tlv;
 	u8 unit;
@@ -424,6 +424,12 @@ static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 		if (ret < 0)
 			return ret;
 
+		if (val < ctype->min.integer)
+			val = ctype->min.integer;
+
+		if (val > ctype->max.integer)
+			val = ctype->max.integer;
+
 		ctl_val->value.integer.value[i] = val;
 	}
 
@@ -447,6 +453,13 @@ static int snd_ctl_audient_integer_set(struct snd_kcontrol *kctl,
 	int changed = 0;
 	int i;
 
+	for (i = 0; i < hwchan; i++) {
+		long val = ctl_val->value.integer.value[i];
+
+		if ((val < ctype->min.integer) || (val > ctype->max.integer))
+			return -EINVAL;
+	}
+
 	CLASS(snd_usb_lock, pm)(mixer->chip);
 	if (pm.err < 0)
 		return pm.err;
-- 
2.56.0

[RFC PATCH 08/11] ALSA: mixer_audient: Add control initialization at probe

[Christian Ruppert]

Add the possibility to initialize certain control types to known values at
probe time. This is particularly useful for controls which initially read
wrong values and for controls which cannot be read at all.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 2f1b332859c9..803487ced997 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -36,6 +36,7 @@ enum snd_audient_type {
 static const DECLARE_TLV_DB_MINMAX_MUTE(snd_audient_tlv_mixer, -12800, 600);
 
 #define SND_AUDIENT_CTYPE_FLAGS_SIGNED		(1L <<  0)
+#define SND_AUDIENT_CTYPE_FLAGS_INIT_HW		(1L <<  1)
 
 static const struct snd_audient_ctrl_type {
 	snd_ctl_elem_type_t type;
@@ -47,6 +48,7 @@ static const struct snd_audient_ctrl_type {
 	union {
 		long integer;
 	} max;		/* for booleans holds physical int value for true */
+	u32 init;
 	const unsigned int *tlv;
 	u8 unit;
 	u8 sel;
@@ -532,6 +534,18 @@ static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
 		return -EINVAL;
 	}
 
+	if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_INIT_HW) {
+		int i;
+
+		for (i = 0; i < ctrl->hwchannels; i++) {
+			int ret = snd_audient_raw_set_one(mixer, ctype,
+							  ctrl->val_offs + i,
+							  ctype->init);
+			if (ret < 0)
+				return ret;
+		}
+	}
+
 	elem = kzalloc_obj(*elem);
 	if (!elem)
 		return -ENOMEM;
-- 
2.56.0

[RFC PATCH 09/11] ALSA: mixer_audient: Add readback-free parameter set

[Christian Ruppert]

Add a flag to systematically force parameter writing without prior readback
to certain control types. In preparation of the id14 driver.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 803487ced997..7cb8245a64d0 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -37,6 +37,7 @@ static const DECLARE_TLV_DB_MINMAX_MUTE(snd_audient_tlv_mixer, -12800, 600);
 
 #define SND_AUDIENT_CTYPE_FLAGS_SIGNED		(1L <<  0)
 #define SND_AUDIENT_CTYPE_FLAGS_INIT_HW		(1L <<  1)
+#define SND_AUDIENT_CTYPE_FLAGS_FORCE_SET	(1L <<  2)
 
 static const struct snd_audient_ctrl_type {
 	snd_ctl_elem_type_t type;
@@ -313,9 +314,13 @@ static int snd_audient_raw_set_one(struct usb_mixer_interface *const mixer,
 	int ret;
 	u32 buf;
 
-	ret = snd_audient_raw_get_one(mixer, ctype, cidx, &buf);
-	if (ret < 0)
-		return ret;
+	if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_FORCE_SET) {
+		buf = !value;		/* just make it different */
+	} else {
+		ret = snd_audient_raw_get_one(mixer, ctype, cidx, &buf);
+		if (ret < 0)
+			return ret;
+	}
 
 	if (buf != value) {
 		buf = cpu_to_le32(value);
-- 
2.56.0

[RFC PATCH 10/11] ALSA: mixer_audient: add control value caching

[Christian Ruppert]

In preparation of id14 support, add control value caching.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 112 +++++++++++++++++++++++++++-----------
 1 file changed, 81 insertions(+), 31 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 7cb8245a64d0..24b594fb1bc7 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -38,6 +38,7 @@ static const DECLARE_TLV_DB_MINMAX_MUTE(snd_audient_tlv_mixer, -12800, 600);
 #define SND_AUDIENT_CTYPE_FLAGS_SIGNED		(1L <<  0)
 #define SND_AUDIENT_CTYPE_FLAGS_INIT_HW		(1L <<  1)
 #define SND_AUDIENT_CTYPE_FLAGS_FORCE_SET	(1L <<  2)
+#define SND_AUDIENT_CTYPE_FLAGS_CACHE		(1L <<  3)
 
 static const struct snd_audient_ctrl_type {
 	snd_ctl_elem_type_t type;
@@ -49,7 +50,7 @@ static const struct snd_audient_ctrl_type {
 	union {
 		long integer;
 	} max;		/* for booleans holds physical int value for true */
-	u32 init;
+	u32 init;	/* hardware and cache are initialized to this value */
 	const unsigned int *tlv;
 	u8 unit;
 	u8 sel;
@@ -89,7 +90,8 @@ static const struct snd_audient_ctrl_type {
 	},
 	[SND_AUDIENT_TYPE_MIXER] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
-		.flags = SND_AUDIENT_CTYPE_FLAGS_SIGNED,
+		.flags = SND_AUDIENT_CTYPE_FLAGS_SIGNED
+			 | SND_AUDIENT_CTYPE_FLAGS_CACHE,
 		.len = 2,
 		.min.integer = -128 * 256,
 		.max.integer = 6 * 256,
@@ -285,11 +287,18 @@ static inline int snd_audient_set_cur(struct usb_mixer_interface *mixer,
 
 static int snd_audient_raw_get_one(struct usb_mixer_interface *const mixer,
 			const struct snd_audient_ctrl_type *const ctype,
+			const u32 *const cache,
 			const u8 cidx, u32 *const value)
 {
 	int ret;
 	s32 buf = 0;
 
+	if (cache) {
+		*value = cache[cidx];
+
+		return ctype->len;
+	}
+
 	ret = snd_audient_get_cur(mixer, ctype, cidx, &buf);
 	if (ret < 0)
 		return ret;
@@ -309,15 +318,16 @@ static int snd_audient_raw_get_one(struct usb_mixer_interface *const mixer,
 
 static int snd_audient_raw_set_one(struct usb_mixer_interface *const mixer,
 			const struct snd_audient_ctrl_type *const ctype,
-			const u8 cidx, const u32 value)
+			u32 *const cache, const u8 cidx, const u32 value,
+			bool force)
 {
 	int ret;
 	u32 buf;
 
-	if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_FORCE_SET) {
+	if ((ctype->flags & SND_AUDIENT_CTYPE_FLAGS_FORCE_SET) || force) {
 		buf = !value;		/* just make it different */
 	} else {
-		ret = snd_audient_raw_get_one(mixer, ctype, cidx, &buf);
+		ret = snd_audient_raw_get_one(mixer, ctype, cache, cidx, &buf);
 		if (ret < 0)
 			return ret;
 	}
@@ -328,6 +338,9 @@ static int snd_audient_raw_set_one(struct usb_mixer_interface *const mixer,
 		if (ret < 0)
 			return ret;
 
+		if (cache)
+			cache[cidx] = value;
+
 		return 1;
 	}
 
@@ -338,8 +351,8 @@ static int snd_audient_raw_set_one(struct usb_mixer_interface *const mixer,
 static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 				       struct snd_ctl_elem_value *ctl_val)
 {
-	struct usb_mixer_elem_list *const list = snd_kcontrol_chip(kctl);
-	struct usb_mixer_interface *const mixer = list->mixer;
+	struct usb_mixer_elem_info *const elem = snd_kcontrol_chip(kctl);
+	struct usb_mixer_interface *const mixer = elem->head.mixer;
 
 	const unsigned int nchan = snd_audient_kctl_channels(kctl);
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
@@ -357,7 +370,8 @@ static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 		u32 buf;
 		int ret;
 
-		ret = snd_audient_raw_get_one(mixer, ctype, base + i, &buf);
+		ret = snd_audient_raw_get_one(mixer, ctype, elem->private_data,
+					      base + i, &buf);
 		if (ret < 0)
 			return ret;
 
@@ -374,8 +388,8 @@ static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
 				       struct snd_ctl_elem_value *ctl_val)
 {
-	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kctl);
-	struct usb_mixer_interface *mixer = list->mixer;
+	struct usb_mixer_elem_info *const elem = snd_kcontrol_chip(kctl);
+	struct usb_mixer_interface *const mixer = elem->head.mixer;
 
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
 	const struct snd_audient_ctrl_type *const ctype
@@ -394,7 +408,8 @@ static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
 							  : ctype->min.integer;
 		int ret;
 
-		ret = snd_audient_raw_set_one(mixer, ctype, base + i, buf);
+		ret = snd_audient_raw_set_one(mixer, ctype, elem->private_data,
+					      base + i, buf, false);
 		if (ret < 0)
 			return ret;
 
@@ -408,8 +423,8 @@ static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
 static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 				   struct snd_ctl_elem_value *ctl_val)
 {
-	struct usb_mixer_elem_list *const list = snd_kcontrol_chip(kctl);
-	struct usb_mixer_interface *const mixer = list->mixer;
+	struct usb_mixer_elem_info *const elem = snd_kcontrol_chip(kctl);
+	struct usb_mixer_interface *const mixer = elem->head.mixer;
 
 	const unsigned int nchan = snd_audient_kctl_channels(kctl);
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
@@ -427,7 +442,8 @@ static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 		s32 val;
 		int ret;
 
-		ret = snd_audient_raw_get_one(mixer, ctype, base + i, &val);
+		ret = snd_audient_raw_get_one(mixer, ctype, elem->private_data,
+					      base + i, &val);
 		if (ret < 0)
 			return ret;
 
@@ -449,8 +465,8 @@ static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 static int snd_ctl_audient_integer_set(struct snd_kcontrol *kctl,
 				   struct snd_ctl_elem_value *ctl_val)
 {
-	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kctl);
-	struct usb_mixer_interface *mixer = list->mixer;
+	struct usb_mixer_elem_info *const elem = snd_kcontrol_chip(kctl);
+	struct usb_mixer_interface *mixer = elem->head.mixer;
 
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
 	const struct snd_audient_ctrl_type *const ctype
@@ -475,7 +491,8 @@ static int snd_ctl_audient_integer_set(struct snd_kcontrol *kctl,
 		s32 val = ctl_val->value.integer.value[i];
 		int ret;
 
-		ret = snd_audient_raw_set_one(mixer, ctype, base + i, val);
+		ret = snd_audient_raw_set_one(mixer, ctype, elem->private_data,
+					      base + i, val, false);
 		if (ret < 0)
 			return ret;
 
@@ -516,6 +533,8 @@ static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
 	struct snd_kcontrol *kctl;
 	struct usb_mixer_elem_info *elem;
 
+	int ret;
+
 	knew.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
 	knew.name = ctrl->name;
 	knew.info = snd_ctl_audient_info;
@@ -523,7 +542,9 @@ static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
 						   ctrl->hwchannels);
 	knew.tlv.p = ctype->tlv;
 	knew.access = SNDRV_CTL_ELEM_ACCESS_READWRITE
-			| SNDRV_CTL_ELEM_ACCESS_VOLATILE
+			| ((ctype->flags & SND_AUDIENT_CTYPE_FLAGS_CACHE)
+			   ? 0
+			   : SNDRV_CTL_ELEM_ACCESS_VOLATILE)
 			| (ctype->tlv ? SNDRV_CTL_ELEM_ACCESS_TLV_READ : 0);
 
 	switch (ctype->type) {
@@ -539,34 +560,63 @@ static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
 		return -EINVAL;
 	}
 
+	elem = kzalloc(sizeof(*elem)
+		       + ((ctype->flags & SND_AUDIENT_CTYPE_FLAGS_CACHE)
+			  ? (sizeof(u32) * ctrl->hwchannels)
+			  : 0),
+		       GFP_KERNEL);
+	if (!elem)
+		return -ENOMEM;
+
+	elem->head.mixer = mixer;
+	elem->channels = ctrl->channels;
+
+	if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_CACHE)
+		elem->private_data = elem + 1;
+
 	if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_INIT_HW) {
 		int i;
 
 		for (i = 0; i < ctrl->hwchannels; i++) {
-			int ret = snd_audient_raw_set_one(mixer, ctype,
-							  ctrl->val_offs + i,
-							  ctype->init);
+			ret = snd_audient_raw_set_one(mixer, ctype,
+						      elem->private_data,
+						      ctrl->val_offs + i,
+						      ctype->init, true);
 			if (ret < 0)
-				return ret;
+				goto free_elem;
 		}
-	}
-
-	elem = kzalloc_obj(*elem);
-	if (!elem)
-		return -ENOMEM;
+	} else if (elem->private_data) {
+		u32 *const cache = elem->private_data;
+		int i;
 
-	elem->head.mixer = mixer;
-	elem->channels = ctrl->channels;
+		if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_FORCE_SET)
+			for (i = 0; i < ctrl->hwchannels; i++)
+				cache[i] = ctype->init;
+		else
+			for (i = 0; i < ctrl->hwchannels; i++) {
+				ret = snd_audient_raw_get_one(
+							mixer, ctype, NULL,
+							ctrl->val_offs + i,
+							cache + i);
+				if (ret < 0)
+					goto free_elem;
+			}
+	}
 
 	kctl = snd_ctl_new1(&knew, elem);
 	if (!kctl) {
-		kfree(elem);
-		return -ENOMEM;
+		ret = -ENOMEM;
+		goto free_elem;
 	}
 
 	kctl->private_free = snd_usb_mixer_elem_free;
 
 	return snd_usb_mixer_add_control(&elem->head, kctl);
+
+free_elem:
+	kfree(elem);
+
+	return ret;
 }
 
 
-- 
2.56.0

[RFC PATCH 11/11] ALSA: mixer_audient: Create matrix programmatically

[Christian Ruppert]

Most Audient devices seem to have a similar mixer matrix with many
identical channels. The only difference between devices seems to be
the matrix' dimension. Create it programmatically in a loop rather
than from the controls table.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 75 +++++++++++++++++----------------------
 1 file changed, 32 insertions(+), 43 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 24b594fb1bc7..30f2f20b1dbb 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -103,7 +103,7 @@ static const struct snd_audient_ctrl_type {
 
 
 struct snd_audient_ctrl {
-	char *name;
+	const char *const name;
 	enum snd_audient_type type;
 	unsigned int channels;
 	unsigned int hwchannels;
@@ -132,48 +132,6 @@ static const struct snd_audient_ctrl snd_audient_evo4_controls[] = {
 		.hwchannels = 1,
 		.val_offs = 0,
 	},
-	{
-		.name = "Mic 1 Capture Volume",
-		.type = SND_AUDIENT_TYPE_MIXER,
-		.channels = 2,
-		.hwchannels = 2,
-		.val_offs = 0,
-	},
-	{
-		.name = "Mic 2 Capture Volume",
-		.type = SND_AUDIENT_TYPE_MIXER,
-		.channels = 2,
-		.hwchannels = 2,
-		.val_offs = 2,
-	},
-	{
-		.name = "Master Left Capture Volume",
-		.type = SND_AUDIENT_TYPE_MIXER,
-		.channels = 2,
-		.hwchannels = 2,
-		.val_offs = 4,
-	},
-	{
-		.name = "Master Right Capture Volume",
-		.type = SND_AUDIENT_TYPE_MIXER,
-		.channels = 2,
-		.hwchannels = 2,
-		.val_offs = 6,
-	},
-	{
-		.name = "Loopback Left Capture Volume",
-		.type = SND_AUDIENT_TYPE_MIXER,
-		.channels = 2,
-		.hwchannels = 2,
-		.val_offs = 8,
-	},
-	{
-		.name = "Loopback Right Capture Volume",
-		.type = SND_AUDIENT_TYPE_MIXER,
-		.channels = 2,
-		.hwchannels = 2,
-		.val_offs = 10,
-	},
 	{
 		.name = "Mic 1 Phantom Capture Switch",
 		.type = SND_AUDIENT_TYPE_PHANTOM,
@@ -191,13 +149,27 @@ static const struct snd_audient_ctrl snd_audient_evo4_controls[] = {
 	{ 0 }, /* sentinel */
 };
 
+static const char *const snd_audient_evo4_matrix[] = {
+	"Mic 1 Capture Volume",
+	"Mic 2 Capture Volume",
+	"Master Left Capture Volume",
+	"Master Right Capture Volume",
+	"Loopback Left Capture Volume",
+	"Loopback Right Capture Volume",
+	NULL
+};
+
 static const struct audient_devinfo {
 	u32 usb_id;
 	const struct snd_audient_ctrl *controls;
+	const char *const *const matrix_names;
+	const unsigned int matrix_channels;
 } audient_devinfo[] = {
 	{
 		.usb_id = USB_ID(USB_AUDIENT_VID, USB_EVO4_PID),
 		.controls = snd_audient_evo4_controls,
+		.matrix_names = snd_audient_evo4_matrix,
+		.matrix_channels = 2,
 	},
 	{ 0 } /* sentinel */
 };
@@ -626,6 +598,8 @@ int snd_audient_controls_create(struct usb_mixer_interface *mixer)
 	const struct audient_devinfo *info;
 	const struct snd_audient_ctrl *ctrl;
 
+	int i;
+
 	for (info = audient_devinfo; info->controls; info++)
 		if (info->usb_id == mixer->chip->usb_id)
 			break;
@@ -640,5 +614,20 @@ int snd_audient_controls_create(struct usb_mixer_interface *mixer)
 			return ret;
 	}
 
+	for (i = 0; info->matrix_names[i]; i++) {
+		const struct snd_audient_ctrl c = {
+			.name = info->matrix_names[i],
+			.type = SND_AUDIENT_TYPE_MIXER,
+			.channels = info->matrix_channels,
+			.hwchannels = info->matrix_channels,
+			.val_offs = i * info->matrix_channels,
+		};
+
+		const int ret = snd_audient_add_ctrl(mixer, &c);
+
+		if (ret < 0)
+			return ret;
+	}
+
 	return 0;
 }
-- 
2.56.0

Re: [RFC PATCH 00/11] Re: ALSA: usb-audio: Audient iD14 MkI vendor controls

[Will Porter]

Hi Christian,

Thanks for the RFC, and for splitting it into small patches. It made
the review easy, and the cover letter answers my three questions.

I compiled mixer_audient.c after each patch with W=1, out of tree
against a 7.2 kernel's headers: no warnings. checkpatch --strict
gives only CHECK-level style notes. I can't test on an EVO, so the
points below come from reading the code.

1. Patch 10, cache index

The cache has hwchannels entries, and the probe fills it by element
index (cache[i]). But get, put and the INIT_HW write index it by device
channel:

    *value = cache[cidx];    /* cidx = val_offs + i */
    cache[cidx] = value;

So a nonzero val_offs can access past the allocation. On the EVO4,
"Mic 2 Capture Volume" (val_offs 2) uses cache[2] and cache[3] of a
2-entry array, and "Loopback Right Capture Volume" uses cache[10] and
cache[11]. Those rows would also show other memory, not the value read
at probe. On the iD14 the last matrix element would use cache[54] and
cache[55].

Would indexing relative to the element fix it? The diff at the end of
this mail passes the cache entry of channel i instead of the array, so
that raw_get_one() and raw_set_one() never see cidx for the cache.

2. Probe-time USB errors now fail the whole card

With patch 10 the EVO matrix is read at probe, and with INIT_HW a
control is written at probe. If one of those transfers fails,
snd_audient_controls_create() returns the error, snd_usb_create_mixer()
fails, and the card does not register. As far as I can see,
QUIRK_FLAG_IGNORE_CTL_ERROR does not suppress errors returned by
snd_usb_mixer_apply_create_quirk(). Before this series the quirk sent no
USB traffic at probe, so this is new.

Could we keep the card registering after a failed probe transfer, while
keeping the cache entry invalid until a transfer succeeds?

To save a round, I wrote it out; the diff is at the end of this mail, on
top of your series. Please change or drop anything that doesn't fit your
plans.

It gives each cache entry a valid flag, set when a transfer confirms the
value (a read, or a write that succeeded). A failed probe transfer logs
a warning and keeps the control with an invalid entry. For a cached
write-only control, get still succeeds after a failed probe write, so
that failure alone does not stop alsactl store: boolean and integer
controls return their minimum, and my enum type reports "Unknown". A
readable control retries the GET and returns an error if that retry
fails. Since a get can now fill the cache, the callbacks take
mixer->lock. Control allocation and registration errors still fail the
probe. It contains the point 1 fix as well, since both change the same
cache code.

On the iD14 I tested it with a test-only control that the device
refuses (polarity on Digi 3). The card registered, the log showed one
warning for that control, and get returned off. A put returned -EPIPE;
a subsequent get still returned off.

3. Smaller points

- Patch 05: would sign_extend32(buf, 8 * ctype->len - 1) work in
  place of the shift pair?
- Patch 05: the buffers mix u32/s32 with cpu_to_le32()/le32_to_cpu().
  Would __le32 buffers keep sparse quiet?
- Patch 05: the transfer buffer is 4 bytes on the stack, but nothing
  checks the table's len. Could snd_audient_add_ctrl() return -EINVAL
  unless 1 <= len <= 4?
- Patch 09: with FORCE_SET, a put of the cached value still writes
  (good) but also reports a change, so each alsactl restore sends a
  change event for every such control. Could it write but return 0
  when the cache already holds the value?
- Patch 11: a device with no matrix list would dereference NULL in the
  loop. Would a check on info->matrix_names be worth adding?
- Patch 01: FYI, the file header still says "Audient EVO driver for
  ALSA".

4. iD14 tables on top

I built the iD14 tables on your series, with the cache fix applied.
On an iD14 MkI they passed control read and write checks, the range
checks and a loopback test of the matrix crosspoints. The crosspoints
also kept their values across a module reload and were read back into
the cache.

On top of your patches I needed three generic additions:

- a step size for integer types (res): the iD14 level controls use
  s16 in 1/256 dB; I expose them in whole-dB steps, matching the
  volume knob. The control counts steps from min, as the generic USB
  mixer does with the RANGE resolution;
- an enumerated type with a value list, plus one extra last item that
  a get shows for a device value outside the list;
- a per-device create hook, for the FU 12 control that does not fit
  the tables (in the same patch as that control).

The matrix uses your loop as it is: with 2 channels per element and the
names in the order Mic 1 Main, Mic 1 Cue, Mic 2 Main, ..., element n
starts at CN 2 * n, which is input * 4 + output on the iD14. Does that
fit what you had in mind?

5. Next steps

Would you prefer to incorporate these changes in an RFC v2, or shall I
fold them into the relevant patches when I carry your series, with
notes in the commit messages?

Thanks,
Will

-- >8 --
From: Will Porter <mrwillporter@gmail.com>
Subject: [RFC PATCH] ALSA: mixer_audient: Fix cache indexing and probe error handling

The cache has hwchannels entries, but get, put and the INIT_HW write
indexed it with the device channel (val_offs + i). Pass the entry of
element channel i instead.

A failed probe transfer made snd_audient_controls_create() fail, so
the card did not register. Give each cache entry a valid flag, set
when a transfer confirms the value: a read, or a write that
succeeded. A failed probe transfer logs a warning and leaves the entry
invalid. A readable control then reads the device on its next get,
and returns an error if that read fails; a write-only (FORCE_SET)
control shows its minimum until a put succeeds. CACHE | FORCE_SET
without INIT_HW keeps the earlier behaviour: the init value is
assumed, without a transfer.

A get can now fill the cache, and the control core runs gets in
parallel, so the callbacks take mixer->lock around the transfers and
the cache.

Control allocation and registration errors still fail the probe.

Assisted-by: Claude:claude-opus-5-5
Signed-off-by: Will Porter <mrwillporter@gmail.com>
---
Proposed changes to patches 08 and 10.

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 30f2f20..ef8fcdf 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -210,6 +210,26 @@ static inline u16 snd_audient_kctl_channels(struct snd_kcontrol *kctl)
 	return info->channels;
 }
 
+/*
+ * A cached value is valid once a transfer confirmed it: a read, or a write
+ * that succeeded. A probe transfer that fails leaves it invalid. CACHE |
+ * FORCE_SET without INIT_HW keeps the earlier behaviour: the init value is
+ * assumed, without a transfer.
+ */
+struct snd_audient_cache_entry {
+	u32 value;
+	bool valid;
+};
+
+/* Cache entry of element channel i, or NULL for an uncached control. */
+static inline struct snd_audient_cache_entry *
+snd_audient_cache_slot(struct usb_mixer_elem_info *elem, unsigned int i)
+{
+	struct snd_audient_cache_entry *const cache = elem->private_data;
+
+	return cache ? cache + i : NULL;
+}
+
 
 #define AUDIENT_REQTYPE_SET (USB_DIR_OUT | USB_TYPE_CLASS \
 					 | USB_RECIP_INTERFACE)
@@ -259,18 +279,25 @@ static inline int snd_audient_set_cur(struct usb_mixer_interface *mixer,
 
 static int snd_audient_raw_get_one(struct usb_mixer_interface *const mixer,
 			const struct snd_audient_ctrl_type *const ctype,
-			const u32 *const cache,
+			struct snd_audient_cache_entry *const slot,
 			const u8 cidx, u32 *const value)
 {
 	int ret;
 	s32 buf = 0;
 
-	if (cache) {
-		*value = cache[cidx];
+	if (slot && slot->valid) {
+		*value = slot->value;
 
 		return ctype->len;
 	}
 
+	/*
+	 * Cached FORCE_SET controls are treated as write-only: an invalid
+	 * cache entry does not trigger a GET.
+	 */
+	if (slot && (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_FORCE_SET))
+		return -ENODATA;
+
 	ret = snd_audient_get_cur(mixer, ctype, cidx, &buf);
 	if (ret < 0)
 		return ret;
@@ -285,12 +312,18 @@ static int snd_audient_raw_get_one(struct usb_mixer_interface *const mixer,
 
 	*value = buf;
 
+	if (slot) {
+		slot->value = buf;
+		slot->valid = true;
+	}
+
 	return ret;
 }
 
 static int snd_audient_raw_set_one(struct usb_mixer_interface *const mixer,
 			const struct snd_audient_ctrl_type *const ctype,
-			u32 *const cache, const u8 cidx, const u32 value,
+			struct snd_audient_cache_entry *const slot,
+			const u8 cidx, const u32 value,
 			bool force)
 {
 	int ret;
@@ -299,7 +332,7 @@ static int snd_audient_raw_set_one(struct usb_mixer_interface *const mixer,
 	if ((ctype->flags & SND_AUDIENT_CTYPE_FLAGS_FORCE_SET) || force) {
 		buf = !value;		/* just make it different */
 	} else {
-		ret = snd_audient_raw_get_one(mixer, ctype, cache, cidx, &buf);
+		ret = snd_audient_raw_get_one(mixer, ctype, slot, cidx, &buf);
 		if (ret < 0)
 			return ret;
 	}
@@ -310,8 +343,10 @@ static int snd_audient_raw_set_one(struct usb_mixer_interface *const mixer,
 		if (ret < 0)
 			return ret;
 
-		if (cache)
-			cache[cidx] = value;
+		if (slot) {
+			slot->value = value;
+			slot->valid = true;
+		}
 
 		return 1;
 	}
@@ -337,14 +372,18 @@ static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 	CLASS(snd_usb_lock, pm)(mixer->chip);
 	if (pm.err < 0)
 		return pm.err;
+	/* serializes the transfers and the cache, also between gets */
+	guard(mutex)(&mixer->lock);
 
 	for (i = 0; i < hwchan; i++) {
 		u32 buf;
 		int ret;
 
-		ret = snd_audient_raw_get_one(mixer, ctype, elem->private_data,
+		ret = snd_audient_raw_get_one(mixer, ctype, snd_audient_cache_slot(elem, i),
 					      base + i, &buf);
-		if (ret < 0)
+		if (ret == -ENODATA)	/* unknown write-only value: off */
+			buf = ctype->min.integer;
+		else if (ret < 0)
 			return ret;
 
 		ctl_val->value.integer.value[i] = (buf == ctype->min.integer)
@@ -374,13 +413,15 @@ static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
 	CLASS(snd_usb_lock, pm)(mixer->chip);
 	if (pm.err < 0)
 		return pm.err;
+	/* serializes the transfers and the cache, also between gets */
+	guard(mutex)(&mixer->lock);
 
 	for (i = 0; i < hwchan; i++) {
 		u32 buf = ctl_val->value.integer.value[i] ? ctype->max.integer
 							  : ctype->min.integer;
 		int ret;
 
-		ret = snd_audient_raw_set_one(mixer, ctype, elem->private_data,
+		ret = snd_audient_raw_set_one(mixer, ctype, snd_audient_cache_slot(elem, i),
 					      base + i, buf, false);
 		if (ret < 0)
 			return ret;
@@ -409,14 +450,18 @@ static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 	CLASS(snd_usb_lock, pm)(mixer->chip);
 	if (pm.err < 0)
 		return pm.err;
+	/* serializes the transfers and the cache, also between gets */
+	guard(mutex)(&mixer->lock);
 
 	for (i = 0; i < hwchan; i++) {
 		s32 val;
 		int ret;
 
-		ret = snd_audient_raw_get_one(mixer, ctype, elem->private_data,
+		ret = snd_audient_raw_get_one(mixer, ctype, snd_audient_cache_slot(elem, i),
 					      base + i, &val);
-		if (ret < 0)
+		if (ret == -ENODATA)	/* unknown write-only value: minimum */
+			val = ctype->min.integer;
+		else if (ret < 0)
 			return ret;
 
 		if (val < ctype->min.integer)
@@ -458,12 +503,14 @@ static int snd_ctl_audient_integer_set(struct snd_kcontrol *kctl,
 	CLASS(snd_usb_lock, pm)(mixer->chip);
 	if (pm.err < 0)
 		return pm.err;
+	/* serializes the transfers and the cache, also between gets */
+	guard(mutex)(&mixer->lock);
 
 	for (i = 0; i < hwchan; i++) {
 		s32 val = ctl_val->value.integer.value[i];
 		int ret;
 
-		ret = snd_audient_raw_set_one(mixer, ctype, elem->private_data,
+		ret = snd_audient_raw_set_one(mixer, ctype, snd_audient_cache_slot(elem, i),
 					      base + i, val, false);
 		if (ret < 0)
 			return ret;
@@ -534,7 +581,8 @@ static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
 
 	elem = kzalloc(sizeof(*elem)
 		       + ((ctype->flags & SND_AUDIENT_CTYPE_FLAGS_CACHE)
-			  ? (sizeof(u32) * ctrl->hwchannels)
+			  ? (sizeof(struct snd_audient_cache_entry)
+			     * ctrl->hwchannels)
 			  : 0),
 		       GFP_KERNEL);
 	if (!elem)
@@ -546,33 +594,44 @@ static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
 	if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_CACHE)
 		elem->private_data = elem + 1;
 
+	/*
+	 * A failed probe transfer must not fail the card: warn and keep the
+	 * control. Its cache entry stays invalid, so a readable control reads
+	 * the device again on its next get, and a write-only control shows an
+	 * unknown value until a put succeeds.
+	 */
 	if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_INIT_HW) {
 		int i;
 
 		for (i = 0; i < ctrl->hwchannels; i++) {
 			ret = snd_audient_raw_set_one(mixer, ctype,
-						      elem->private_data,
+						      snd_audient_cache_slot(elem, i),
 						      ctrl->val_offs + i,
 						      ctype->init, true);
 			if (ret < 0)
-				goto free_elem;
+				usb_audio_warn(mixer->chip,
+					       "%s: cannot set channel %d (%d)\n",
+					       ctrl->name, i, ret);
 		}
 	} else if (elem->private_data) {
-		u32 *const cache = elem->private_data;
+		struct snd_audient_cache_entry *const cache = elem->private_data;
 		int i;
 
-		if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_FORCE_SET)
-			for (i = 0; i < ctrl->hwchannels; i++)
-				cache[i] = ctype->init;
-		else
-			for (i = 0; i < ctrl->hwchannels; i++) {
-				ret = snd_audient_raw_get_one(
-							mixer, ctype, NULL,
-							ctrl->val_offs + i,
-							cache + i);
-				if (ret < 0)
-					goto free_elem;
+		for (i = 0; i < ctrl->hwchannels; i++) {
+			if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_FORCE_SET) {
+				cache[i].value = ctype->init;
+				cache[i].valid = true;
+				continue;
 			}
+
+			ret = snd_audient_raw_get_one(mixer, ctype, cache + i,
+						      ctrl->val_offs + i,
+						      &cache[i].value);
+			if (ret < 0)
+				usb_audio_warn(mixer->chip,
+					       "%s: cannot read channel %d (%d)\n",
+					       ctrl->name, i, ret);
+		}
 	}
 
 	kctl = snd_ctl_new1(&knew, elem);

[RFC V2 PATCH 00/11] Re: ALSA: usb-audio: Audient iD14 MkI vendor

[Christian Ruppert]

Hi Will,

On Sun, Nov 01, 2026 at 11:35:57AM -0600, Will Porter wrote:
> [...]
> 
> 1. Patch 10, cache index
> 
> The cache has hwchannels entries, and the probe fills it by element
> index (cache[i]). But get, put and the INIT_HW write index it by device
> channel:
> [...]

Good catch and thanks for the fix, applied in RFC V2.

> 2. Probe-time USB errors now fail the whole card
> [...]
> Could we keep the card registering after a failed probe transfer, while
> keeping the cache entry invalid until a transfer succeeds?
> 
> To save a round, I wrote it out; the diff is at the end of this mail, on
> top of your series. Please change or drop anything that doesn't fit your
> plans.
> [...]

Fine with me, I suppose the question if individual reads should be allowed
to fail during driver initialization is more philosophical in this case.
I don't see any harm. Patch applied in RFC V2

> 3. Smaller points
> 
> - Patch 05: would sign_extend32(buf, 8 * ctype->len - 1) work in
>   place of the shift pair?
> - Patch 05: the buffers mix u32/s32 with cpu_to_le32()/le32_to_cpu().
>   Would __le32 buffers keep sparse quiet?

OK, these make the code a bit cleaner, added to RFC V2.

> - Patch 05: the transfer buffer is 4 bytes on the stack, but nothing
>   checks the table's len. Could snd_audient_add_ctrl() return -EINVAL
>   unless 1 <= len <= 4?

I don't think this is necessary as it should be rather obvious to everyone
touching the driver that the u32 argument can't carry more than 4 bytes.
Added a comment to the parameter definition.

> - Patch 09: with FORCE_SET, a put of the cached value still writes
>   (good) but also reports a change, so each alsactl restore sends a
>   change event for every such control. Could it write but return 0
>   when the cache already holds the value?

Makes sense. Added to RFC V2 (in patch 10 where the cache is added). Please
double-check if the logic reflects what you had in mind.

> - Patch 11: a device with no matrix list would dereference NULL in the
>   loop. Would a check on info->matrix_names be worth adding?

Makes sense although this could also be held off until somebody actually
adds such a device. Added to RFC V2.

> - Patch 01: FYI, the file header still says "Audient EVO driver for
>   ALSA".

Fixed in RFC V2.

> 4. iD14 tables on top
> 
> I built the iD14 tables on your series, with the cache fix applied.
> On an iD14 MkI they passed control read and write checks, the range
> checks and a loopback test of the matrix crosspoints. The crosspoints
> also kept their values across a module reload and were read back into
> the cache.
> 
> On top of your patches I needed three generic additions:
> 
> - a step size for integer types (res): the iD14 level controls use
>   s16 in 1/256 dB; I expose them in whole-dB steps, matching the
>   volume knob. The control counts steps from min, as the generic USB
>   mixer does with the RANGE resolution;
> - an enumerated type with a value list, plus one extra last item that
>   a get shows for a device value outside the list;
> - a per-device create hook, for the FU 12 control that does not fit
>   the tables (in the same patch as that control).
> 
> The matrix uses your loop as it is: with 2 channels per element and the
> names in the order Mic 1 Main, Mic 1 Cue, Mic 2 Main, ..., element n
> starts at CN 2 * n, which is input * 4 + output on the iD14. Does that
> fit what you had in mind?

Yep, sounds good.

> 5. Next steps
> 
> Would you prefer to incorporate these changes in an RFC v2, or shall I
> fold them into the relevant patches when I carry your series, with
> notes in the commit messages?

I created RFC V2 with your patch and the fixes you suggested. This will
make things easier to review when we submit the everything, compared to
fixes on top of a long series of patches.

Based on the same commit as before and retested on 7.3.1.

  Christian

Christian Ruppert (11):
  ALSA: rename mixer_evo to mixer_audient
  ALSA: mixer_audient: explicitly define full control names
  ALSA: mixer_audient: clarify USB control message definition
  ALSA: mixer_audient: Add length check to USB transfer
  ALSA: mixer_audient: make USB control transfer size configurable
  ALSA: mixer_audient: Allow arbitrary boolean control values
  ALSA: mixer_audient: Add integer range checks
  ALSA: mixer_audient: Add control initialization at probe
  ALSA: mixer_audient: Add readback-free parameter set
  ALSA: mixer_audient: add control value caching
  ALSA: mixer_audient: Create matrix programmatically

 MAINTAINERS               |   7 +-
 sound/usb/Makefile        |   2 +-
 sound/usb/mixer_audient.c | 702 ++++++++++++++++++++++++++++++++++++++
 sound/usb/mixer_audient.h |  12 +
 sound/usb/mixer_evo.c     | 526 ----------------------------
 sound/usb/mixer_evo.h     |  12 -
 sound/usb/mixer_quirks.c  |   4 +-
 7 files changed, 721 insertions(+), 544 deletions(-)
 create mode 100644 sound/usb/mixer_audient.c
 create mode 100644 sound/usb/mixer_audient.h
 delete mode 100644 sound/usb/mixer_evo.c
 delete mode 100644 sound/usb/mixer_evo.h

-- 
2.56.0

[RFC V2 PATCH 01/11] ALSA: rename mixer_evo to mixer_audient

[Christian Ruppert]

Rename mixer_evo files and functions to *_audient in preparation of a more
generic driver for audient devices.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 MAINTAINERS                                |   7 +-
 sound/usb/Makefile                         |   2 +-
 sound/usb/{mixer_evo.c => mixer_audient.c} | 249 +++++++++++----------
 sound/usb/mixer_audient.h                  |  12 +
 sound/usb/mixer_evo.h                      |  12 -
 sound/usb/mixer_quirks.c                   |   4 +-
 6 files changed, 148 insertions(+), 138 deletions(-)
 rename sound/usb/{mixer_evo.c => mixer_audient.c} (54%)
 create mode 100644 sound/usb/mixer_audient.h
 delete mode 100644 sound/usb/mixer_evo.h

diff --git a/MAINTAINERS b/MAINTAINERS
index fee9d090b280..a1139ae3404d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4354,12 +4354,13 @@ F:	drivers/net/ieee802154/at86rf230.h
 F:	drivers/net/ieee802154/atusb.c
 F:	drivers/net/ieee802154/atusb.h
 
-AUDIENT EVO MIXER DRIVER
+AUDIENT MIXER DRIVER
 M:	Christian Ruppert <arc@gmx.li>
+M:	Will Porter <mrwillporter@gmail.com>
 L:	linux-sound@vger.kernel.org
 S:	Maintained
-F:	sound/usb/mixer_evo.c
-F:	sound/usb/mixer_evo.h
+F:	sound/usb/mixer_audient.c
+F:	sound/usb/mixer_audient.h
 
 AUDIT SUBSYSTEM
 M:	Paul Moore <paul@paul-moore.com>
diff --git a/sound/usb/Makefile b/sound/usb/Makefile
index 2e842dcc73de..44f4e4c820fb 100644
--- a/sound/usb/Makefile
+++ b/sound/usb/Makefile
@@ -11,7 +11,7 @@ snd-usb-audio-y := 	card.o \
 			helper.o \
 			implicit.o \
 			mixer.o \
-			mixer_evo.o \
+			mixer_audient.o \
 			mixer_quirks.o \
 			mixer_scarlett.o \
 			mixer_scarlett2.o \
diff --git a/sound/usb/mixer_evo.c b/sound/usb/mixer_audient.c
similarity index 54%
rename from sound/usb/mixer_evo.c
rename to sound/usb/mixer_audient.c
index c1e0332232f2..e2700b08cf80 100644
--- a/sound/usb/mixer_evo.c
+++ b/sound/usb/mixer_audient.c
@@ -1,9 +1,9 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * Audient EVO driver for ALSA
+ * Audient driver for ALSA
  * Copyright (C) 2026 Christian Ruppert <arc@gmx.li>
  *
- * Based on the work of Ivan Hazucha for audient-evo-py.
+ * EVO4 support is based on the work of Ivan Hazucha for audient-evo-py.
  * https://github.com/vanzaho/audient-evo-py/
  */
 
@@ -20,22 +20,22 @@
 #include "mixer.h"
 #include "mixer_quirks.h"
 #include "helper.h"
-#include "mixer_evo.h"
+#include "mixer_audient.h"
 
 
-enum snd_evo_type {
-	SND_EVO_TYPE_MONITOR = 0,
-	SND_EVO_TYPE_PHANTOM,
-	SND_EVO_TYPE_MUTE,
-	SND_EVO_TYPE_MUTE_OUT,
-	SND_EVO_TYPE_MIXER,
-	SND_EVO_TYPE_NCTYPES
+enum snd_audient_type {
+	SND_AUDIENT_TYPE_MONITOR = 0,
+	SND_AUDIENT_TYPE_PHANTOM,
+	SND_AUDIENT_TYPE_MUTE,
+	SND_AUDIENT_TYPE_MUTE_OUT,
+	SND_AUDIENT_TYPE_MIXER,
+	SND_AUDIENT_TYPE_NCTYPES
 };
 
 /* Mixer matrix: -128dB (mute) to +6dB */
-static const DECLARE_TLV_DB_MINMAX_MUTE(snd_evo_tlv_mixer, -12800, 600);
+static const DECLARE_TLV_DB_MINMAX_MUTE(snd_audient_tlv_mixer, -12800, 600);
 
-static const struct snd_evo_ctrl_type {
+static const struct snd_audient_ctrl_type {
 	snd_ctl_elem_type_t type;
 	bool invert;
 	union {
@@ -47,8 +47,8 @@ static const struct snd_evo_ctrl_type {
 	const unsigned int *tlv;
 	u16 wValue;
 	u16 wIndex;
-} snd_evo_ctypes[SND_EVO_TYPE_NCTYPES] = {
-	[SND_EVO_TYPE_MONITOR] = {
+} snd_audient_ctypes[SND_AUDIENT_TYPE_NCTYPES] = {
+	[SND_AUDIENT_TYPE_MONITOR] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
 		.min.integer = 0,
 		.max.integer = 127,
@@ -56,7 +56,7 @@ static const struct snd_evo_ctrl_type {
 		.wIndex = 0x3800,
 		/* no TLV here because we can't describe the cross-fader */
 	},
-	[SND_EVO_TYPE_PHANTOM] = {
+	[SND_AUDIENT_TYPE_PHANTOM] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = false,
 		.min.integer = 0,
@@ -64,7 +64,7 @@ static const struct snd_evo_ctrl_type {
 		.wValue = 0x0000,
 		.wIndex = 0x3A00,
 	},
-	[SND_EVO_TYPE_MUTE] = {
+	[SND_AUDIENT_TYPE_MUTE] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = true,
 		.min.integer = 0,
@@ -72,7 +72,7 @@ static const struct snd_evo_ctrl_type {
 		.wValue = 0x0200,
 		.wIndex = 0x3A00,
 	},
-	[SND_EVO_TYPE_MUTE_OUT] = {
+	[SND_AUDIENT_TYPE_MUTE_OUT] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = true,
 		.min.integer = 0,
@@ -80,135 +80,135 @@ static const struct snd_evo_ctrl_type {
 		.wValue = 0x0100,
 		.wIndex = 0x3B00,
 	},
-	[SND_EVO_TYPE_MIXER] = {
+	[SND_AUDIENT_TYPE_MIXER] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
 		.min.integer = -128 * 256,
 		.max.integer = 6 * 256,
 		.wValue = 0x0100,
 		.wIndex = 0x3C00,
-		.tlv = snd_evo_tlv_mixer,
+		.tlv = snd_audient_tlv_mixer,
 	},
 };
 
-#define SND_EVO_FLAGS_DIRECTION (1L<<0)
-#define SND_EVO_FLAGS_CAPTURE (1L<<0)
-#define SND_EVO_FLAGS_PLAYBACK (0L<<0)
+#define SND_AUDIENT_FLAGS_DIRECTION (1L<<0)
+#define SND_AUDIENT_FLAGS_CAPTURE (1L<<0)
+#define SND_AUDIENT_FLAGS_PLAYBACK (0L<<0)
 
-struct snd_evo_ctrl {
+struct snd_audient_ctrl {
 	char *basename;
-	enum snd_evo_type type;
+	enum snd_audient_type type;
 	unsigned int channels;
 	unsigned int hwchannels;
 	unsigned int val_offs;
 	unsigned long flags;
 };
 
-static const struct snd_evo_ctrl evo4_controls[] = {
+static const struct snd_audient_ctrl snd_audient_evo4_controls[] = {
 	{
 		.basename = "Master",
-		.type = SND_EVO_TYPE_MUTE_OUT,
+		.type = SND_AUDIENT_TYPE_MUTE_OUT,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 0,
-		.flags = SND_EVO_FLAGS_PLAYBACK,
+		.flags = SND_AUDIENT_FLAGS_PLAYBACK,
 	},
 	{
 		.basename = "Mic",
-		.type = SND_EVO_TYPE_MUTE,
+		.type = SND_AUDIENT_TYPE_MUTE,
 		.channels = 4,
 		.hwchannels = 2,
 		.val_offs = 0,
-		.flags = SND_EVO_FLAGS_PLAYBACK,
+		.flags = SND_AUDIENT_FLAGS_PLAYBACK,
 	},
 	{
 		.basename = "Monitor",
-		.type = SND_EVO_TYPE_MONITOR,
+		.type = SND_AUDIENT_TYPE_MONITOR,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 0,
-		.flags = SND_EVO_FLAGS_PLAYBACK,
+		.flags = SND_AUDIENT_FLAGS_PLAYBACK,
 	},
 	{
 		.basename = "Mic 1",
-		.type = SND_EVO_TYPE_MIXER,
+		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 0,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
 		.basename = "Mic 2",
-		.type = SND_EVO_TYPE_MIXER,
+		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 2,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
 		.basename = "Master Left",
-		.type = SND_EVO_TYPE_MIXER,
+		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 4,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
 		.basename = "Master Right",
-		.type = SND_EVO_TYPE_MIXER,
+		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 6,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
 		.basename = "Loopback Left",
-		.type = SND_EVO_TYPE_MIXER,
+		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 8,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
 		.basename = "Loopback Right",
-		.type = SND_EVO_TYPE_MIXER,
+		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 10,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
 		.basename = "Mic 1 Phantom",
-		.type = SND_EVO_TYPE_PHANTOM,
+		.type = SND_AUDIENT_TYPE_PHANTOM,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 0,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
 		.basename = "Mic 2 Phantom",
-		.type = SND_EVO_TYPE_PHANTOM,
+		.type = SND_AUDIENT_TYPE_PHANTOM,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 1,
-		.flags = SND_EVO_FLAGS_CAPTURE,
+		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{ 0 }, /* sentinel */
 };
 
-static const struct evo_devinfo {
+static const struct audient_devinfo {
 	u32 usb_id;
-	const struct snd_evo_ctrl *controls;
-} evo_devinfo[] = {
+	const struct snd_audient_ctrl *controls;
+} audient_devinfo[] = {
 	{
 		.usb_id = USB_ID(USB_AUDIENT_VID, USB_EVO4_PID),
-		.controls = evo4_controls,
+		.controls = snd_audient_evo4_controls,
 	},
 	{ 0 } /* sentinel */
 };
 
 
-static inline unsigned long snd_evo_kctl_priv(enum snd_evo_type type,
-					      u8 valoffs, u8 hwchannels)
+static inline unsigned long snd_audient_kctl_priv(enum snd_audient_type type,
+						  u8 valoffs, u8 hwchannels)
 {
 	unsigned long type_l = type & 0xFF;
 	unsigned long valoffs_l = valoffs & 0xFF;
@@ -218,22 +218,24 @@ static inline unsigned long snd_evo_kctl_priv(enum snd_evo_type type,
 }
 
 static __always_inline
-const struct snd_evo_ctrl_type *snd_evo_kctl_type(struct snd_kcontrol *kctl)
+const struct snd_audient_ctrl_type *snd_audient_kctl_type(struct snd_kcontrol
+							  *kctl)
 {
-	return &snd_evo_ctypes[kctl->private_value & 0xFF];
+	return &snd_audient_ctypes[kctl->private_value & 0xFF];
 }
 
-static __always_inline u16 snd_evo_kctl_valoffs(struct snd_kcontrol *kctl)
+static __always_inline u16 snd_audient_kctl_valoffs(struct snd_kcontrol *kctl)
 {
 	return (kctl->private_value >> 8) & 0xFF;
 }
 
-static __always_inline u16 snd_evo_kctl_hwchannels(struct snd_kcontrol *kctl)
+static __always_inline
+u16 snd_audient_kctl_hwchannels(struct snd_kcontrol *kctl)
 {
 	return (kctl->private_value >> 16) & 0xFF;
 }
 
-static inline u16 snd_evo_kctl_channels(struct snd_kcontrol *kctl)
+static inline u16 snd_audient_kctl_channels(struct snd_kcontrol *kctl)
 {
 	struct usb_mixer_elem_info *info = kctl->private_data;
 
@@ -241,43 +243,45 @@ static inline u16 snd_evo_kctl_channels(struct snd_kcontrol *kctl)
 }
 
 
-#define EVO_REQ_CUR (0x01)
-#define EVO_REQTYPE_SET (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE)
-#define EVO_REQTYPE_GET (USB_DIR_IN  | USB_TYPE_CLASS | USB_RECIP_INTERFACE)
+#define AUDIENT_REQTYPE_SET (USB_DIR_OUT | USB_TYPE_CLASS \
+					 | USB_RECIP_INTERFACE)
+#define AUDIENT_REQTYPE_GET (USB_DIR_IN  | USB_TYPE_CLASS \
+					 | USB_RECIP_INTERFACE)
 
-static inline int snd_evo_get_cur(struct usb_mixer_interface *mixer,
-				  u16 value, u16 index,
-				  void *buf, size_t len)
+static inline int snd_audient_get_cur(struct usb_mixer_interface *mixer,
+				      u16 value, u16 index,
+				      void *buf, size_t len)
 {
 	struct usb_device *const dev = mixer->chip->dev;
 
 	return snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
-			       EVO_REQ_CUR, EVO_REQTYPE_GET,
+			       UAC2_CS_CUR, AUDIENT_REQTYPE_GET,
 			       value, index, buf, len);
 }
 
-static inline int snd_evo_set_cur(struct usb_mixer_interface *mixer,
-				  u16 value, u16 index,
-				  void *buf, size_t len)
+static inline int snd_audient_set_cur(struct usb_mixer_interface *mixer,
+				      u16 value, u16 index,
+				      void *buf, size_t len)
 {
 	struct usb_device *const dev = mixer->chip->dev;
 
 	return snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0),
-			       EVO_REQ_CUR, EVO_REQTYPE_SET,
+			       UAC2_CS_CUR, AUDIENT_REQTYPE_SET,
 			       value, index, buf, len);
 }
 
 
-static int snd_ctl_evo_boolean_get(struct snd_kcontrol *kctl,
-				   struct snd_ctl_elem_value *ctl_val)
+static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
+				       struct snd_ctl_elem_value *ctl_val)
 {
 	struct usb_mixer_elem_list *const list = snd_kcontrol_chip(kctl);
 	struct usb_mixer_interface *const mixer = list->mixer;
 
-	const unsigned int nchan = snd_evo_kctl_channels(kctl);
-	const unsigned int hwchan = snd_evo_kctl_hwchannels(kctl);
-	const struct snd_evo_ctrl_type *const ctype = snd_evo_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_evo_kctl_valoffs(kctl);
+	const unsigned int nchan = snd_audient_kctl_channels(kctl);
+	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
+	const struct snd_audient_ctrl_type *const ctype
+						= snd_audient_kctl_type(kctl);
+	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
 	const u16 index = ctype->wIndex;
 
 	int i;
@@ -290,8 +294,8 @@ static int snd_ctl_evo_boolean_get(struct snd_kcontrol *kctl,
 		u32 buf;
 		int ret;
 
-		ret = snd_evo_get_cur(mixer, value + i, index,
-				      &buf, sizeof(buf));
+		ret = snd_audient_get_cur(mixer, value + i, index,
+					  &buf, sizeof(buf));
 		if (ret < 0)
 			return ret;
 
@@ -309,15 +313,16 @@ static int snd_ctl_evo_boolean_get(struct snd_kcontrol *kctl,
 	return 0;
 }
 
-static int snd_ctl_evo_boolean_set(struct snd_kcontrol *kctl,
-				   struct snd_ctl_elem_value *ctl_val)
+static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
+				       struct snd_ctl_elem_value *ctl_val)
 {
 	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kctl);
 	struct usb_mixer_interface *mixer = list->mixer;
 
-	const unsigned int hwchan = snd_evo_kctl_hwchannels(kctl);
-	const struct snd_evo_ctrl_type *const ctype = snd_evo_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_evo_kctl_valoffs(kctl);
+	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
+	const struct snd_audient_ctrl_type *const ctype
+						= snd_audient_kctl_type(kctl);
+	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
 	const u16 index = ctype->wIndex;
 
 	int changed = 0;
@@ -335,7 +340,7 @@ static int snd_ctl_evo_boolean_set(struct snd_kcontrol *kctl,
 		if (ctype->invert)
 			buf ^= cpu_to_le32(0x1);
 
-		ret = snd_evo_get_cur(mixer, value + i, index,
+		ret = snd_audient_get_cur(mixer, value + i, index,
 				      &rbuf, sizeof(rbuf));
 		if (ret < 0)
 			return ret;
@@ -343,8 +348,8 @@ static int snd_ctl_evo_boolean_set(struct snd_kcontrol *kctl,
 		if (rbuf != buf) {
 			changed = 1;
 
-			ret = snd_evo_set_cur(mixer, value + i, index,
-					      &buf, sizeof(buf));
+			ret = snd_audient_set_cur(mixer, value + i, index,
+						  &buf, sizeof(buf));
 			if (ret < 0)
 				return ret;
 		}
@@ -353,16 +358,17 @@ static int snd_ctl_evo_boolean_set(struct snd_kcontrol *kctl,
 	return changed;
 }
 
-static int snd_ctl_evo_integer_get(struct snd_kcontrol *kctl,
+static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 				   struct snd_ctl_elem_value *ctl_val)
 {
 	struct usb_mixer_elem_list *const list = snd_kcontrol_chip(kctl);
 	struct usb_mixer_interface *const mixer = list->mixer;
 
-	const unsigned int nchan = snd_evo_kctl_channels(kctl);
-	const unsigned int hwchan = snd_evo_kctl_hwchannels(kctl);
-	const struct snd_evo_ctrl_type *const ctype = snd_evo_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_evo_kctl_valoffs(kctl);
+	const unsigned int nchan = snd_audient_kctl_channels(kctl);
+	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
+	const struct snd_audient_ctrl_type *const ctype
+						= snd_audient_kctl_type(kctl);
+	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
 	const u16 index = ctype->wIndex;
 
 	int i;
@@ -376,8 +382,8 @@ static int snd_ctl_evo_integer_get(struct snd_kcontrol *kctl,
 		s16 val;
 		int ret;
 
-		ret = snd_evo_get_cur(mixer, value + i, index,
-				      &buf, sizeof(buf));
+		ret = snd_audient_get_cur(mixer, value + i, index,
+					  &buf, sizeof(buf));
 		if (ret < 0)
 			return ret;
 
@@ -391,15 +397,16 @@ static int snd_ctl_evo_integer_get(struct snd_kcontrol *kctl,
 	return 0;
 }
 
-static int snd_ctl_evo_integer_set(struct snd_kcontrol *kctl,
+static int snd_ctl_audient_integer_set(struct snd_kcontrol *kctl,
 				   struct snd_ctl_elem_value *ctl_val)
 {
 	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kctl);
 	struct usb_mixer_interface *mixer = list->mixer;
 
-	const unsigned int hwchan = snd_evo_kctl_hwchannels(kctl);
-	const struct snd_evo_ctrl_type *const ctype = snd_evo_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_evo_kctl_valoffs(kctl);
+	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
+	const struct snd_audient_ctrl_type *const ctype
+						= snd_audient_kctl_type(kctl);
+	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
 	const u16 index = ctype->wIndex;
 
 	int changed = 0;
@@ -414,16 +421,16 @@ static int snd_ctl_evo_integer_set(struct snd_kcontrol *kctl,
 		s16 buf = cpu_to_le16(ctl_val->value.integer.value[i]);
 		int ret;
 
-		ret = snd_evo_get_cur(mixer, value + i, index,
-				      &rbuf, sizeof(rbuf));
+		ret = snd_audient_get_cur(mixer, value + i, index,
+					  &rbuf, sizeof(rbuf));
 		if (ret < 0)
 			return ret;
 
 		if (rbuf != buf) {
 			changed = 1;
 
-			ret = snd_evo_set_cur(mixer, value + i, index,
-					      &buf, sizeof(buf));
+			ret = snd_audient_set_cur(mixer, value + i, index,
+						  &buf, sizeof(buf));
 			if (ret < 0)
 				return ret;
 		}
@@ -432,23 +439,25 @@ static int snd_ctl_evo_integer_set(struct snd_kcontrol *kctl,
 	return changed;
 }
 
-static int snd_ctl_evo_info(struct snd_kcontrol *kctl,
+static int snd_ctl_audient_info(struct snd_kcontrol *kctl,
 			    struct snd_ctl_elem_info *uinfo)
 {
-	const struct snd_evo_ctrl_type *const ctype = snd_evo_kctl_type(kctl);
+	const struct snd_audient_ctrl_type *const ctype
+						= snd_audient_kctl_type(kctl);
 
 	uinfo->type = ctype->type;
-	uinfo->count = snd_evo_kctl_channels(kctl);
+	uinfo->count = snd_audient_kctl_channels(kctl);
 	uinfo->value.integer.min = ctype->min.integer;
 	uinfo->value.integer.max = ctype->max.integer;
 	return 0;
 }
 
 
-static int snd_evo_add_ctrl(struct usb_mixer_interface *mixer,
-			    const struct snd_evo_ctrl *ctrl)
+static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
+			    const struct snd_audient_ctrl *ctrl)
 {
-	const struct snd_evo_ctrl_type *ctype = &snd_evo_ctypes[ctrl->type];
+	const struct snd_audient_ctrl_type *ctype
+					= &snd_audient_ctypes[ctrl->type];
 	char name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
 	struct snd_kcontrol_new knew = { 0 };
 	struct snd_kcontrol *kctl;
@@ -456,9 +465,9 @@ static int snd_evo_add_ctrl(struct usb_mixer_interface *mixer,
 
 	knew.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
 	knew.name = name;
-	knew.info = snd_ctl_evo_info;
-	knew.private_value = snd_evo_kctl_priv(ctrl->type, ctrl->val_offs,
-					       ctrl->hwchannels);
+	knew.info = snd_ctl_audient_info;
+	knew.private_value = snd_audient_kctl_priv(ctrl->type, ctrl->val_offs,
+						   ctrl->hwchannels);
 	knew.tlv.p = ctype->tlv;
 	knew.access = SNDRV_CTL_ELEM_ACCESS_READWRITE
 			| SNDRV_CTL_ELEM_ACCESS_VOLATILE
@@ -466,20 +475,20 @@ static int snd_evo_add_ctrl(struct usb_mixer_interface *mixer,
 
 	switch (ctype->type) {
 	case SNDRV_CTL_ELEM_TYPE_INTEGER:
-		knew.get = snd_ctl_evo_integer_get;
-		knew.put = snd_ctl_evo_integer_set;
+		knew.get = snd_ctl_audient_integer_get;
+		knew.put = snd_ctl_audient_integer_set;
 		break;
 	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
-		knew.get = snd_ctl_evo_boolean_get;
-		knew.put = snd_ctl_evo_boolean_set;
+		knew.get = snd_ctl_audient_boolean_get;
+		knew.put = snd_ctl_audient_boolean_set;
 		break;
 	default:
 		return -EINVAL;
 	}
 
 	snprintf(name, sizeof(name), "%s %s %s", ctrl->basename,
-		 ((ctrl->flags & SND_EVO_FLAGS_DIRECTION)
-			== SND_EVO_FLAGS_CAPTURE) ? "Capture" : "Playback",
+		 ((ctrl->flags & SND_AUDIENT_FLAGS_DIRECTION)
+			== SND_AUDIENT_FLAGS_CAPTURE) ? "Capture" : "Playback",
 		 (ctype->type == SNDRV_CTL_ELEM_TYPE_BOOLEAN)
 			? "Switch" : "Volume");
 
@@ -503,12 +512,12 @@ static int snd_evo_add_ctrl(struct usb_mixer_interface *mixer,
 
 
 /* called from mixer_quirks.c */
-int snd_evo_controls_create(struct usb_mixer_interface *mixer)
+int snd_audient_controls_create(struct usb_mixer_interface *mixer)
 {
-	const struct evo_devinfo *info;
-	const struct snd_evo_ctrl *ctrl;
+	const struct audient_devinfo *info;
+	const struct snd_audient_ctrl *ctrl;
 
-	for (info = evo_devinfo; info->controls; info++)
+	for (info = audient_devinfo; info->controls; info++)
 		if (info->usb_id == mixer->chip->usb_id)
 			break;
 
@@ -516,7 +525,7 @@ int snd_evo_controls_create(struct usb_mixer_interface *mixer)
 		return -ENODEV;
 
 	for (ctrl = info->controls; ctrl->basename; ctrl++) {
-		const int ret = snd_evo_add_ctrl(mixer, ctrl);
+		const int ret = snd_audient_add_ctrl(mixer, ctrl);
 
 		if (ret < 0)
 			return ret;
diff --git a/sound/usb/mixer_audient.h b/sound/usb/mixer_audient.h
new file mode 100644
index 000000000000..db4f31e02b5e
--- /dev/null
+++ b/sound/usb/mixer_audient.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __USB_MIXER_AUDIENT_H
+#define __USB_MIXER_AUDIENT_H
+
+#include "mixer.h"
+
+#define USB_AUDIENT_VID (0x2708)
+#define USB_EVO4_PID (0x0006)
+
+int snd_audient_controls_create(struct usb_mixer_interface *mixer);
+
+#endif /* __USB_MIXER_AUDIENT_H */
diff --git a/sound/usb/mixer_evo.h b/sound/usb/mixer_evo.h
deleted file mode 100644
index 7fe7e197185c..000000000000
--- a/sound/usb/mixer_evo.h
+++ /dev/null
@@ -1,12 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __USB_MIXER_EVO_H
-#define __USB_MIXER_EVO_H
-
-#include "mixer.h"
-
-#define USB_AUDIENT_VID (0x2708)
-#define USB_EVO4_PID (0x0006)
-
-int snd_evo_controls_create(struct usb_mixer_interface *mixer);
-
-#endif /* __USB_MIXER_EVO_H */
diff --git a/sound/usb/mixer_quirks.c b/sound/usb/mixer_quirks.c
index 01210cc3fae7..af53c5c20e65 100644
--- a/sound/usb/mixer_quirks.c
+++ b/sound/usb/mixer_quirks.c
@@ -38,7 +38,7 @@
 #include "mixer_scarlett2.h"
 #include "mixer_us16x08.h"
 #include "mixer_s1810c.h"
-#include "mixer_evo.h"
+#include "mixer_audient.h"
 #include "helper.h"
 #include "fcp.h"
 
@@ -4541,7 +4541,7 @@ int snd_usb_mixer_apply_create_quirk(struct usb_mixer_interface *mixer)
 		break;
 
 	case USB_ID(USB_AUDIENT_VID, USB_EVO4_PID): /* Audient EVO 4 */
-		err = snd_evo_controls_create(mixer);
+		err = snd_audient_controls_create(mixer);
 		break;
 
 	case USB_ID(0x041e, 0x323b): /* Creative Sound Blaster E1 */
-- 
2.56.0

[RFC V2 PATCH 02/11] ALSA: mixer_audient: explicitly define full control names

[Christian Ruppert]

Previously, control names were dynamically created depending if the
control was an input or an output, a volume or a switch. Get rid of this
logic by simply defining the full name in the control structure.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 50 +++++++++++----------------------------
 1 file changed, 14 insertions(+), 36 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index e2700b08cf80..2afef52a12d9 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -90,107 +90,92 @@ static const struct snd_audient_ctrl_type {
 	},
 };
 
-#define SND_AUDIENT_FLAGS_DIRECTION (1L<<0)
-#define SND_AUDIENT_FLAGS_CAPTURE (1L<<0)
-#define SND_AUDIENT_FLAGS_PLAYBACK (0L<<0)
 
 struct snd_audient_ctrl {
-	char *basename;
+	char *name;
 	enum snd_audient_type type;
 	unsigned int channels;
 	unsigned int hwchannels;
 	unsigned int val_offs;
-	unsigned long flags;
 };
 
 static const struct snd_audient_ctrl snd_audient_evo4_controls[] = {
 	{
-		.basename = "Master",
+		.name = "Master Playback Switch",
 		.type = SND_AUDIENT_TYPE_MUTE_OUT,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 0,
-		.flags = SND_AUDIENT_FLAGS_PLAYBACK,
 	},
 	{
-		.basename = "Mic",
+		.name = "Mic Playback Switch",
 		.type = SND_AUDIENT_TYPE_MUTE,
 		.channels = 4,
 		.hwchannels = 2,
 		.val_offs = 0,
-		.flags = SND_AUDIENT_FLAGS_PLAYBACK,
 	},
 	{
-		.basename = "Monitor",
+		.name = "Monitor Playback Volume",
 		.type = SND_AUDIENT_TYPE_MONITOR,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 0,
-		.flags = SND_AUDIENT_FLAGS_PLAYBACK,
 	},
 	{
-		.basename = "Mic 1",
+		.name = "Mic 1 Capture Volume",
 		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 0,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
-		.basename = "Mic 2",
+		.name = "Mic 2 Capture Volume",
 		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 2,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
-		.basename = "Master Left",
+		.name = "Master Left Capture Volume",
 		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 4,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
-		.basename = "Master Right",
+		.name = "Master Right Capture Volume",
 		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 6,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
-		.basename = "Loopback Left",
+		.name = "Loopback Left Capture Volume",
 		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 8,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
-		.basename = "Loopback Right",
+		.name = "Loopback Right Capture Volume",
 		.type = SND_AUDIENT_TYPE_MIXER,
 		.channels = 2,
 		.hwchannels = 2,
 		.val_offs = 10,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
-		.basename = "Mic 1 Phantom",
+		.name = "Mic 1 Phantom Capture Switch",
 		.type = SND_AUDIENT_TYPE_PHANTOM,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 0,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{
-		.basename = "Mic 2 Phantom",
+		.name = "Mic 2 Phantom Capture Switch",
 		.type = SND_AUDIENT_TYPE_PHANTOM,
 		.channels = 1,
 		.hwchannels = 1,
 		.val_offs = 1,
-		.flags = SND_AUDIENT_FLAGS_CAPTURE,
 	},
 	{ 0 }, /* sentinel */
 };
@@ -458,13 +443,12 @@ static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
 {
 	const struct snd_audient_ctrl_type *ctype
 					= &snd_audient_ctypes[ctrl->type];
-	char name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
 	struct snd_kcontrol_new knew = { 0 };
 	struct snd_kcontrol *kctl;
 	struct usb_mixer_elem_info *elem;
 
 	knew.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
-	knew.name = name;
+	knew.name = ctrl->name;
 	knew.info = snd_ctl_audient_info;
 	knew.private_value = snd_audient_kctl_priv(ctrl->type, ctrl->val_offs,
 						   ctrl->hwchannels);
@@ -486,12 +470,6 @@ static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
 		return -EINVAL;
 	}
 
-	snprintf(name, sizeof(name), "%s %s %s", ctrl->basename,
-		 ((ctrl->flags & SND_AUDIENT_FLAGS_DIRECTION)
-			== SND_AUDIENT_FLAGS_CAPTURE) ? "Capture" : "Playback",
-		 (ctype->type == SNDRV_CTL_ELEM_TYPE_BOOLEAN)
-			? "Switch" : "Volume");
-
 	elem = kzalloc_obj(*elem);
 	if (!elem)
 		return -ENOMEM;
@@ -524,7 +502,7 @@ int snd_audient_controls_create(struct usb_mixer_interface *mixer)
 	if (!info->controls)
 		return -ENODEV;
 
-	for (ctrl = info->controls; ctrl->basename; ctrl++) {
+	for (ctrl = info->controls; ctrl->name; ctrl++) {
 		const int ret = snd_audient_add_ctrl(mixer, ctrl);
 
 		if (ret < 0)
-- 
2.56.0

[RFC V2 PATCH 03/11] ALSA: mixer_audient: clarify USB control message definition

[Christian Ruppert]

Previously, base values for wIndex and wValue were directly given in the
control type. Construct them from a unit ID and selector for clarity.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 76 +++++++++++++++++++++------------------
 1 file changed, 41 insertions(+), 35 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 2afef52a12d9..63714d00592c 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -45,15 +45,15 @@ static const struct snd_audient_ctrl_type {
 		int integer;
 	} max;
 	const unsigned int *tlv;
-	u16 wValue;
-	u16 wIndex;
+	u8 unit;
+	u8 sel;
 } snd_audient_ctypes[SND_AUDIENT_TYPE_NCTYPES] = {
 	[SND_AUDIENT_TYPE_MONITOR] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
 		.min.integer = 0,
 		.max.integer = 127,
-		.wValue = 0x0000,
-		.wIndex = 0x3800,
+		.unit = 0x38,
+		.sel = 0x00,
 		/* no TLV here because we can't describe the cross-fader */
 	},
 	[SND_AUDIENT_TYPE_PHANTOM] = {
@@ -61,31 +61,31 @@ static const struct snd_audient_ctrl_type {
 		.invert = false,
 		.min.integer = 0,
 		.max.integer = 1,
-		.wValue = 0x0000,
-		.wIndex = 0x3A00,
+		.unit = 0x3A,
+		.sel = 0x00,
 	},
 	[SND_AUDIENT_TYPE_MUTE] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = true,
 		.min.integer = 0,
 		.max.integer = 1,
-		.wValue = 0x0200,
-		.wIndex = 0x3A00,
+		.unit = 0x3A,
+		.sel = 0x02,
 	},
 	[SND_AUDIENT_TYPE_MUTE_OUT] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = true,
 		.min.integer = 0,
 		.max.integer = 1,
-		.wValue = 0x0100,
-		.wIndex = 0x3B00,
+		.unit = 0x3B,
+		.sel = 0x01,
 	},
 	[SND_AUDIENT_TYPE_MIXER] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
 		.min.integer = -128 * 256,
 		.max.integer = 6 * 256,
-		.wValue = 0x0100,
-		.wIndex = 0x3C00,
+		.unit = 0x3C,
+		.sel = 0x01,
 		.tlv = snd_audient_tlv_mixer,
 	},
 };
@@ -209,7 +209,7 @@ const struct snd_audient_ctrl_type *snd_audient_kctl_type(struct snd_kcontrol
 	return &snd_audient_ctypes[kctl->private_value & 0xFF];
 }
 
-static __always_inline u16 snd_audient_kctl_valoffs(struct snd_kcontrol *kctl)
+static __always_inline u16 snd_audient_kctl_cidxoffs(struct snd_kcontrol *kctl)
 {
 	return (kctl->private_value >> 8) & 0xFF;
 }
@@ -233,11 +233,16 @@ static inline u16 snd_audient_kctl_channels(struct snd_kcontrol *kctl)
 #define AUDIENT_REQTYPE_GET (USB_DIR_IN  | USB_TYPE_CLASS \
 					 | USB_RECIP_INTERFACE)
 
+#define U8_U8(HI, LO) ((((u16)(HI)) << 8) | ((LO) & 0xFF))
+
 static inline int snd_audient_get_cur(struct usb_mixer_interface *mixer,
-				      u16 value, u16 index,
-				      void *buf, size_t len)
+				      const u8 unit, const u8 sel,
+				      const u8 cidx,
+				      void *const buf, const size_t len)
 {
 	struct usb_device *const dev = mixer->chip->dev;
+	const u16 value = U8_U8(sel, cidx);
+	const u16 index = U8_U8(unit, mixer->hostif->desc.bInterfaceNumber);
 
 	return snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
 			       UAC2_CS_CUR, AUDIENT_REQTYPE_GET,
@@ -245,10 +250,13 @@ static inline int snd_audient_get_cur(struct usb_mixer_interface *mixer,
 }
 
 static inline int snd_audient_set_cur(struct usb_mixer_interface *mixer,
-				      u16 value, u16 index,
-				      void *buf, size_t len)
+				      const u8 unit, const u8 sel,
+				      const u8 cidx,
+				      void *const buf, const size_t len)
 {
 	struct usb_device *const dev = mixer->chip->dev;
+	const u16 value = U8_U8(sel, cidx);
+	const u16 index = U8_U8(unit, mixer->hostif->desc.bInterfaceNumber);
 
 	return snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0),
 			       UAC2_CS_CUR, AUDIENT_REQTYPE_SET,
@@ -266,8 +274,7 @@ static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
 	const struct snd_audient_ctrl_type *const ctype
 						= snd_audient_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
-	const u16 index = ctype->wIndex;
+	const u8 base = snd_audient_kctl_cidxoffs(kctl);
 
 	int i;
 
@@ -279,8 +286,8 @@ static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 		u32 buf;
 		int ret;
 
-		ret = snd_audient_get_cur(mixer, value + i, index,
-					  &buf, sizeof(buf));
+		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
+					  base + i, &buf, sizeof(buf));
 		if (ret < 0)
 			return ret;
 
@@ -307,8 +314,7 @@ static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
 	const struct snd_audient_ctrl_type *const ctype
 						= snd_audient_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
-	const u16 index = ctype->wIndex;
+	const u8 base = snd_audient_kctl_cidxoffs(kctl);
 
 	int changed = 0;
 	int i;
@@ -325,15 +331,16 @@ static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
 		if (ctype->invert)
 			buf ^= cpu_to_le32(0x1);
 
-		ret = snd_audient_get_cur(mixer, value + i, index,
-				      &rbuf, sizeof(rbuf));
+		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
+					  base + i, &rbuf, sizeof(rbuf));
 		if (ret < 0)
 			return ret;
 
 		if (rbuf != buf) {
 			changed = 1;
 
-			ret = snd_audient_set_cur(mixer, value + i, index,
+			ret = snd_audient_set_cur(mixer, ctype->unit,
+						  ctype->sel, base + i,
 						  &buf, sizeof(buf));
 			if (ret < 0)
 				return ret;
@@ -353,8 +360,7 @@ static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
 	const struct snd_audient_ctrl_type *const ctype
 						= snd_audient_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
-	const u16 index = ctype->wIndex;
+	const u8 base = snd_audient_kctl_cidxoffs(kctl);
 
 	int i;
 
@@ -367,8 +373,8 @@ static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 		s16 val;
 		int ret;
 
-		ret = snd_audient_get_cur(mixer, value + i, index,
-					  &buf, sizeof(buf));
+		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
+					  base + i, &buf, sizeof(buf));
 		if (ret < 0)
 			return ret;
 
@@ -391,8 +397,7 @@ static int snd_ctl_audient_integer_set(struct snd_kcontrol *kctl,
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
 	const struct snd_audient_ctrl_type *const ctype
 						= snd_audient_kctl_type(kctl);
-	const u16 value = ctype->wValue + snd_audient_kctl_valoffs(kctl);
-	const u16 index = ctype->wIndex;
+	const u8 base = snd_audient_kctl_cidxoffs(kctl);
 
 	int changed = 0;
 	int i;
@@ -406,15 +411,16 @@ static int snd_ctl_audient_integer_set(struct snd_kcontrol *kctl,
 		s16 buf = cpu_to_le16(ctl_val->value.integer.value[i]);
 		int ret;
 
-		ret = snd_audient_get_cur(mixer, value + i, index,
-					  &rbuf, sizeof(rbuf));
+		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
+					  base + i, &rbuf, sizeof(rbuf));
 		if (ret < 0)
 			return ret;
 
 		if (rbuf != buf) {
 			changed = 1;
 
-			ret = snd_audient_set_cur(mixer, value + i, index,
+			ret = snd_audient_set_cur(mixer, ctype->unit,
+						  ctype->sel, base + i,
 						  &buf, sizeof(buf));
 			if (ret < 0)
 				return ret;
-- 
2.56.0

[RFC V2 PATCH 04/11] ALSA: mixer_audient: Add length check to USB transfer

[Christian Ruppert]

Check USB control transfers not only for errors but also for expected
length and return -EIO in case of error.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 63714d00592c..1f3744a7c10a 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -244,9 +244,14 @@ static inline int snd_audient_get_cur(struct usb_mixer_interface *mixer,
 	const u16 value = U8_U8(sel, cidx);
 	const u16 index = U8_U8(unit, mixer->hostif->desc.bInterfaceNumber);
 
-	return snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
-			       UAC2_CS_CUR, AUDIENT_REQTYPE_GET,
-			       value, index, buf, len);
+	const int ret = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
+					UAC2_CS_CUR, AUDIENT_REQTYPE_GET,
+					value, index, buf, len);
+
+	if ((ret >= 0) && (ret != len))
+		return -EIO;
+
+	return ret;
 }
 
 static inline int snd_audient_set_cur(struct usb_mixer_interface *mixer,
@@ -258,9 +263,14 @@ static inline int snd_audient_set_cur(struct usb_mixer_interface *mixer,
 	const u16 value = U8_U8(sel, cidx);
 	const u16 index = U8_U8(unit, mixer->hostif->desc.bInterfaceNumber);
 
-	return snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0),
-			       UAC2_CS_CUR, AUDIENT_REQTYPE_SET,
-			       value, index, buf, len);
+	const int ret = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0),
+					UAC2_CS_CUR, AUDIENT_REQTYPE_SET,
+					value, index, buf, len);
+
+	if ((ret >= 0) && (ret != len))
+		return -EIO;
+
+	return ret;
 }
 
 
-- 
2.56.0

[RFC V2 PATCH 05/11] ALSA: mixer_audient: make USB control transfer size configurable

[Christian Ruppert]

Previously, the USB transfer size was hardcoded in the datatype get/set
functions. Make it configurable in the ctype structure in preparation of
new control types for the id14.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 131 ++++++++++++++++++++++++--------------
 1 file changed, 84 insertions(+), 47 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 1f3744a7c10a..57d856d25271 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -12,6 +12,8 @@
 #include <linux/usb.h>
 #include <linux/usb/audio-v2.h>
 #include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/bitops.h>
 #include <sound/core.h>
 #include <sound/control.h>
 #include <sound/tlv.h>
@@ -35,8 +37,12 @@ enum snd_audient_type {
 /* Mixer matrix: -128dB (mute) to +6dB */
 static const DECLARE_TLV_DB_MINMAX_MUTE(snd_audient_tlv_mixer, -12800, 600);
 
+#define SND_AUDIENT_CTYPE_FLAGS_SIGNED		BIT(0)
+
 static const struct snd_audient_ctrl_type {
 	snd_ctl_elem_type_t type;
+	unsigned long flags;
+	size_t len;		/* datatype size, can be 1, 2 or 4 bytes */
 	bool invert;
 	union {
 		int integer;
@@ -50,6 +56,7 @@ static const struct snd_audient_ctrl_type {
 } snd_audient_ctypes[SND_AUDIENT_TYPE_NCTYPES] = {
 	[SND_AUDIENT_TYPE_MONITOR] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
+		.len = 2,
 		.min.integer = 0,
 		.max.integer = 127,
 		.unit = 0x38,
@@ -59,6 +66,7 @@ static const struct snd_audient_ctrl_type {
 	[SND_AUDIENT_TYPE_PHANTOM] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = false,
+		.len = 4,
 		.min.integer = 0,
 		.max.integer = 1,
 		.unit = 0x3A,
@@ -67,6 +75,7 @@ static const struct snd_audient_ctrl_type {
 	[SND_AUDIENT_TYPE_MUTE] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = true,
+		.len = 4,
 		.min.integer = 0,
 		.max.integer = 1,
 		.unit = 0x3A,
@@ -75,6 +84,7 @@ static const struct snd_audient_ctrl_type {
 	[SND_AUDIENT_TYPE_MUTE_OUT] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
 		.invert = true,
+		.len = 4,
 		.min.integer = 0,
 		.max.integer = 1,
 		.unit = 0x3B,
@@ -82,6 +92,8 @@ static const struct snd_audient_ctrl_type {
 	},
 	[SND_AUDIENT_TYPE_MIXER] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
+		.flags = SND_AUDIENT_CTYPE_FLAGS_SIGNED,
+		.len = 2,
 		.min.integer = -128 * 256,
 		.max.integer = 6 * 256,
 		.unit = 0x3C,
@@ -236,44 +248,91 @@ static inline u16 snd_audient_kctl_channels(struct snd_kcontrol *kctl)
 #define U8_U8(HI, LO) ((((u16)(HI)) << 8) | ((LO) & 0xFF))
 
 static inline int snd_audient_get_cur(struct usb_mixer_interface *mixer,
-				      const u8 unit, const u8 sel,
-				      const u8 cidx,
-				      void *const buf, const size_t len)
+			const struct snd_audient_ctrl_type *const ctype,
+			const u8 cidx, void *const buf)
 {
 	struct usb_device *const dev = mixer->chip->dev;
-	const u16 value = U8_U8(sel, cidx);
-	const u16 index = U8_U8(unit, mixer->hostif->desc.bInterfaceNumber);
+	const u16 value = U8_U8(ctype->sel, cidx);
+	const u16 index = U8_U8(ctype->unit,
+				mixer->hostif->desc.bInterfaceNumber);
 
 	const int ret = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
 					UAC2_CS_CUR, AUDIENT_REQTYPE_GET,
-					value, index, buf, len);
+					value, index, buf, ctype->len);
 
-	if ((ret >= 0) && (ret != len))
+	if ((ret >= 0) && (ret != ctype->len))
 		return -EIO;
 
 	return ret;
 }
 
 static inline int snd_audient_set_cur(struct usb_mixer_interface *mixer,
-				      const u8 unit, const u8 sel,
-				      const u8 cidx,
-				      void *const buf, const size_t len)
+			const struct snd_audient_ctrl_type *const ctype,
+			const u8 cidx, void *const buf)
 {
 	struct usb_device *const dev = mixer->chip->dev;
-	const u16 value = U8_U8(sel, cidx);
-	const u16 index = U8_U8(unit, mixer->hostif->desc.bInterfaceNumber);
+	const u16 value = U8_U8(ctype->sel, cidx);
+	const u16 index = U8_U8(ctype->unit,
+				mixer->hostif->desc.bInterfaceNumber);
 
 	const int ret = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0),
 					UAC2_CS_CUR, AUDIENT_REQTYPE_SET,
-					value, index, buf, len);
+					value, index, buf, ctype->len);
 
-	if ((ret >= 0) && (ret != len))
+	if ((ret >= 0) && (ret != ctype->len))
 		return -EIO;
 
 	return ret;
 }
 
 
+static int snd_audient_raw_get_one(struct usb_mixer_interface *const mixer,
+			const struct snd_audient_ctrl_type *const ctype,
+			const u8 cidx, u32 *const value)
+{
+	int ret;
+	__le32 buf = 0;
+	s32 val;
+
+	ret = snd_audient_get_cur(mixer, ctype, cidx, &buf);
+	if (ret < 0)
+		return ret;
+
+	val = le32_to_cpu(buf);
+
+	if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_SIGNED)
+		val = sign_extend32(val, 8 * ctype->len - 1);
+
+	*value = val;
+
+	return ret;
+}
+
+static int snd_audient_raw_set_one(struct usb_mixer_interface *const mixer,
+			const struct snd_audient_ctrl_type *const ctype,
+			const u8 cidx, const u32 value)
+{
+	int ret;
+	u32 val;
+
+	ret = snd_audient_raw_get_one(mixer, ctype, cidx, &val);
+	if (ret < 0)
+		return ret;
+
+	if (val != value) {
+		__le32 buf = cpu_to_le32(value);
+
+		ret = snd_audient_set_cur(mixer, ctype, cidx, &buf);
+		if (ret < 0)
+			return ret;
+
+		return 1;
+	}
+
+	return 0;
+}
+
+
 static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 				       struct snd_ctl_elem_value *ctl_val)
 {
@@ -296,12 +355,11 @@ static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 		u32 buf;
 		int ret;
 
-		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
-					  base + i, &buf, sizeof(buf));
+		ret = snd_audient_raw_get_one(mixer, ctype, base + i, &buf);
 		if (ret < 0)
 			return ret;
 
-		ctl_val->value.integer.value[i] = le32_to_cpu(buf) ? 1 : 0;
+		ctl_val->value.integer.value[i] = buf ? 1 : 0;
 
 		if (ctype->invert)
 			ctl_val->value.integer.value[i] ^= 0x1;
@@ -334,27 +392,18 @@ static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
 		return pm.err;
 
 	for (i = 0; i < hwchan; i++) {
-		u32 rbuf;
-		u32 buf = cpu_to_le32(ctl_val->value.integer.value[i] ? 1 : 0);
+		u32 buf = ctl_val->value.integer.value[i] ? 1 : 0;
 		int ret;
 
 		if (ctype->invert)
-			buf ^= cpu_to_le32(0x1);
+			buf ^= 0x1;
 
-		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
-					  base + i, &rbuf, sizeof(rbuf));
+		ret = snd_audient_raw_set_one(mixer, ctype, base + i, buf);
 		if (ret < 0)
 			return ret;
 
-		if (rbuf != buf) {
+		if (ret)
 			changed = 1;
-
-			ret = snd_audient_set_cur(mixer, ctype->unit,
-						  ctype->sel, base + i,
-						  &buf, sizeof(buf));
-			if (ret < 0)
-				return ret;
-		}
 	}
 
 	return changed;
@@ -379,16 +428,13 @@ static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 		return pm.err;
 
 	for (i = 0; i < hwchan; i++) {
-		u16 buf;
-		s16 val;
+		s32 val;
 		int ret;
 
-		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
-					  base + i, &buf, sizeof(buf));
+		ret = snd_audient_raw_get_one(mixer, ctype, base + i, &val);
 		if (ret < 0)
 			return ret;
 
-		val = le16_to_cpu(buf);
 		ctl_val->value.integer.value[i] = val;
 	}
 
@@ -417,24 +463,15 @@ static int snd_ctl_audient_integer_set(struct snd_kcontrol *kctl,
 		return pm.err;
 
 	for (i = 0; i < hwchan; i++) {
-		s16 rbuf;
-		s16 buf = cpu_to_le16(ctl_val->value.integer.value[i]);
+		s32 val = ctl_val->value.integer.value[i];
 		int ret;
 
-		ret = snd_audient_get_cur(mixer, ctype->unit, ctype->sel,
-					  base + i, &rbuf, sizeof(rbuf));
+		ret = snd_audient_raw_set_one(mixer, ctype, base + i, val);
 		if (ret < 0)
 			return ret;
 
-		if (rbuf != buf) {
+		if (ret)
 			changed = 1;
-
-			ret = snd_audient_set_cur(mixer, ctype->unit,
-						  ctype->sel, base + i,
-						  &buf, sizeof(buf));
-			if (ret < 0)
-				return ret;
-		}
 	}
 
 	return changed;
-- 
2.56.0

[RFC V2 PATCH 06/11] ALSA: mixer_audient: Allow arbitrary boolean control values

[Christian Ruppert]

In preparation of id14 support, allow arbitrary values for true and false
of boolean switches. This also rids us of the tedious invert flag.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 43 ++++++++++++++++++---------------------
 1 file changed, 20 insertions(+), 23 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 57d856d25271..4b20db9a82e2 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -43,13 +43,12 @@ static const struct snd_audient_ctrl_type {
 	snd_ctl_elem_type_t type;
 	unsigned long flags;
 	size_t len;		/* datatype size, can be 1, 2 or 4 bytes */
-	bool invert;
 	union {
 		int integer;
-	} min;
+	} min;		/* for booleans holds physical int value for false */
 	union {
 		int integer;
-	} max;
+	} max;		/* for booleans holds physical int value for true */
 	const unsigned int *tlv;
 	u8 unit;
 	u8 sel;
@@ -65,7 +64,6 @@ static const struct snd_audient_ctrl_type {
 	},
 	[SND_AUDIENT_TYPE_PHANTOM] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
-		.invert = false,
 		.len = 4,
 		.min.integer = 0,
 		.max.integer = 1,
@@ -74,19 +72,17 @@ static const struct snd_audient_ctrl_type {
 	},
 	[SND_AUDIENT_TYPE_MUTE] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
-		.invert = true,
 		.len = 4,
-		.min.integer = 0,
-		.max.integer = 1,
+		.min.integer = 1,
+		.max.integer = 0,
 		.unit = 0x3A,
 		.sel = 0x02,
 	},
 	[SND_AUDIENT_TYPE_MUTE_OUT] = {
 		.type = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
-		.invert = true,
 		.len = 4,
-		.min.integer = 0,
-		.max.integer = 1,
+		.min.integer = 1,
+		.max.integer = 0,
 		.unit = 0x3B,
 		.sel = 0x01,
 	},
@@ -359,16 +355,12 @@ static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 		if (ret < 0)
 			return ret;
 
-		ctl_val->value.integer.value[i] = buf ? 1 : 0;
-
-		if (ctype->invert)
-			ctl_val->value.integer.value[i] ^= 0x1;
+		ctl_val->value.integer.value[i] = (buf == ctype->min.integer)
+						  ? false : true;
 	}
 
 	for (; i < nchan; i++)
-		ctl_val->value.integer.value[i] = ctype->invert
-							? ctype->max.integer
-							: ctype->min.integer;
+		ctl_val->value.integer.value[i] = 0;
 
 	return 0;
 }
@@ -392,12 +384,10 @@ static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
 		return pm.err;
 
 	for (i = 0; i < hwchan; i++) {
-		u32 buf = ctl_val->value.integer.value[i] ? 1 : 0;
+		u32 buf = ctl_val->value.integer.value[i] ? ctype->max.integer
+							  : ctype->min.integer;
 		int ret;
 
-		if (ctype->invert)
-			buf ^= 0x1;
-
 		ret = snd_audient_raw_set_one(mixer, ctype, base + i, buf);
 		if (ret < 0)
 			return ret;
@@ -485,8 +475,15 @@ static int snd_ctl_audient_info(struct snd_kcontrol *kctl,
 
 	uinfo->type = ctype->type;
 	uinfo->count = snd_audient_kctl_channels(kctl);
-	uinfo->value.integer.min = ctype->min.integer;
-	uinfo->value.integer.max = ctype->max.integer;
+
+	if (ctype->type == SNDRV_CTL_ELEM_TYPE_BOOLEAN) {
+		uinfo->value.integer.min = 0;
+		uinfo->value.integer.max = 1;
+	} else {
+		uinfo->value.integer.min = ctype->min.integer;
+		uinfo->value.integer.max = ctype->max.integer;
+	}
+
 	return 0;
 }
 
-- 
2.56.0

[RFC V2 PATCH 07/11] ALSA: mixer_audient: Add integer range checks

[Christian Ruppert]

Add range checks to integer parameters to improve error management:
- Reject out-of-range write attempts with -EINVAL
- Prune out-of-range values returned by the device to the range limits

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 4b20db9a82e2..433bb5479d8e 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -44,10 +44,10 @@ static const struct snd_audient_ctrl_type {
 	unsigned long flags;
 	size_t len;		/* datatype size, can be 1, 2 or 4 bytes */
 	union {
-		int integer;
+		long integer;
 	} min;		/* for booleans holds physical int value for false */
 	union {
-		int integer;
+		long integer;
 	} max;		/* for booleans holds physical int value for true */
 	const unsigned int *tlv;
 	u8 unit;
@@ -425,6 +425,12 @@ static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 		if (ret < 0)
 			return ret;
 
+		if (val < ctype->min.integer)
+			val = ctype->min.integer;
+
+		if (val > ctype->max.integer)
+			val = ctype->max.integer;
+
 		ctl_val->value.integer.value[i] = val;
 	}
 
@@ -448,6 +454,13 @@ static int snd_ctl_audient_integer_set(struct snd_kcontrol *kctl,
 	int changed = 0;
 	int i;
 
+	for (i = 0; i < hwchan; i++) {
+		long val = ctl_val->value.integer.value[i];
+
+		if ((val < ctype->min.integer) || (val > ctype->max.integer))
+			return -EINVAL;
+	}
+
 	CLASS(snd_usb_lock, pm)(mixer->chip);
 	if (pm.err < 0)
 		return pm.err;
-- 
2.56.0

[RFC V2 PATCH 08/11] ALSA: mixer_audient: Add control initialization at probe

[Christian Ruppert]

Add the possibility to initialize certain control types to known values at
probe time. This is particularly useful for controls which initially read
wrong values and for controls which cannot be read at all.

Signed-off-by: Christian Ruppert <arc@gmx.li>
Co-developed-by: Will Porter <mrwillporter@gmail.com>
Signed-off-by: Will Porter <mrwillporter@gmail.com>
Assisted-by: Claude:claude-opus-5-5
---
 sound/usb/mixer_audient.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 433bb5479d8e..70ec3274a5e4 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -38,6 +38,7 @@ enum snd_audient_type {
 static const DECLARE_TLV_DB_MINMAX_MUTE(snd_audient_tlv_mixer, -12800, 600);
 
 #define SND_AUDIENT_CTYPE_FLAGS_SIGNED		BIT(0)
+#define SND_AUDIENT_CTYPE_FLAGS_INIT_HW		BIT(1)
 
 static const struct snd_audient_ctrl_type {
 	snd_ctl_elem_type_t type;
@@ -49,6 +50,7 @@ static const struct snd_audient_ctrl_type {
 	union {
 		long integer;
 	} max;		/* for booleans holds physical int value for true */
+	u32 init;
 	const unsigned int *tlv;
 	u8 unit;
 	u8 sel;
@@ -533,6 +535,20 @@ static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
 		return -EINVAL;
 	}
 
+	if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_INIT_HW) {
+		int i;
+
+		for (i = 0; i < ctrl->hwchannels; i++) {
+			int ret = snd_audient_raw_set_one(mixer, ctype,
+							  ctrl->val_offs + i,
+							  ctype->init);
+			if (ret < 0)
+				usb_audio_warn(mixer->chip,
+					       "%s: cannot set channel %d (%d)\n",
+					       ctrl->name, i, ret);
+		}
+	}
+
 	elem = kzalloc_obj(*elem);
 	if (!elem)
 		return -ENOMEM;
-- 
2.56.0

[RFC V2 PATCH 09/11] ALSA: mixer_audient: Add readback-free parameter set

[Christian Ruppert]

Add a flag to systematically force parameter writing without prior readback
to certain control types. In preparation of the id14 driver.

Signed-off-by: Christian Ruppert <arc@gmx.li>
---
 sound/usb/mixer_audient.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 70ec3274a5e4..f61f9fe61345 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -39,6 +39,7 @@ static const DECLARE_TLV_DB_MINMAX_MUTE(snd_audient_tlv_mixer, -12800, 600);
 
 #define SND_AUDIENT_CTYPE_FLAGS_SIGNED		BIT(0)
 #define SND_AUDIENT_CTYPE_FLAGS_INIT_HW		BIT(1)
+#define SND_AUDIENT_CTYPE_FLAGS_FORCE_SET	BIT(2)
 
 static const struct snd_audient_ctrl_type {
 	snd_ctl_elem_type_t type;
@@ -313,9 +314,13 @@ static int snd_audient_raw_set_one(struct usb_mixer_interface *const mixer,
 	int ret;
 	u32 val;
 
-	ret = snd_audient_raw_get_one(mixer, ctype, cidx, &val);
-	if (ret < 0)
-		return ret;
+	if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_FORCE_SET) {
+		val = !value;		/* just make it different */
+	} else {
+		ret = snd_audient_raw_get_one(mixer, ctype, cidx, &val);
+		if (ret < 0)
+			return ret;
+	}
 
 	if (val != value) {
 		__le32 buf = cpu_to_le32(value);
-- 
2.56.0

[RFC V2 PATCH 10/11] ALSA: mixer_audient: add control value caching

[Christian Ruppert]

In preparation of id14 support, add control value caching.

Signed-off-by: Christian Ruppert <arc@gmx.li>
Co-developed-by: Will Porter <mrwillporter@gmail.com>
Signed-off-by: Will Porter <mrwillporter@gmail.com>
Assisted-by: Claude:claude-opus-5-5
---
 sound/usb/mixer_audient.c | 186 ++++++++++++++++++++++++++++++--------
 1 file changed, 150 insertions(+), 36 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index f61f9fe61345..856fb669af3f 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -40,6 +40,7 @@ static const DECLARE_TLV_DB_MINMAX_MUTE(snd_audient_tlv_mixer, -12800, 600);
 #define SND_AUDIENT_CTYPE_FLAGS_SIGNED		BIT(0)
 #define SND_AUDIENT_CTYPE_FLAGS_INIT_HW		BIT(1)
 #define SND_AUDIENT_CTYPE_FLAGS_FORCE_SET	BIT(2)
+#define SND_AUDIENT_CTYPE_FLAGS_CACHE		BIT(3)
 
 static const struct snd_audient_ctrl_type {
 	snd_ctl_elem_type_t type;
@@ -51,7 +52,7 @@ static const struct snd_audient_ctrl_type {
 	union {
 		long integer;
 	} max;		/* for booleans holds physical int value for true */
-	u32 init;
+	u32 init;	/* hardware and cache are initialized to this value */
 	const unsigned int *tlv;
 	u8 unit;
 	u8 sel;
@@ -91,7 +92,8 @@ static const struct snd_audient_ctrl_type {
 	},
 	[SND_AUDIENT_TYPE_MIXER] = {
 		.type = SNDRV_CTL_ELEM_TYPE_INTEGER,
-		.flags = SND_AUDIENT_CTYPE_FLAGS_SIGNED,
+		.flags = SND_AUDIENT_CTYPE_FLAGS_SIGNED
+			 | SND_AUDIENT_CTYPE_FLAGS_CACHE,
 		.len = 2,
 		.min.integer = -128 * 256,
 		.max.integer = 6 * 256,
@@ -238,6 +240,26 @@ static inline u16 snd_audient_kctl_channels(struct snd_kcontrol *kctl)
 	return info->channels;
 }
 
+/*
+ * A cached value is valid once a transfer confirmed it: a read, or a write
+ * that succeeded. A probe transfer that fails leaves it invalid. CACHE |
+ * FORCE_SET without INIT_HW keeps the earlier behaviour: the init value is
+ * assumed, without a transfer.
+ */
+struct snd_audient_cache_entry {
+	u32 value;
+	bool valid;
+};
+
+/* Cache entry of element channel i, or NULL for an uncached control. */
+static inline struct snd_audient_cache_entry *
+snd_audient_cache_slot(struct usb_mixer_elem_info *elem, unsigned int i)
+{
+	struct snd_audient_cache_entry *const cache = elem->private_data;
+
+	return cache ? cache + i : NULL;
+}
+
 
 #define AUDIENT_REQTYPE_SET (USB_DIR_OUT | USB_TYPE_CLASS \
 					 | USB_RECIP_INTERFACE)
@@ -287,12 +309,26 @@ static inline int snd_audient_set_cur(struct usb_mixer_interface *mixer,
 
 static int snd_audient_raw_get_one(struct usb_mixer_interface *const mixer,
 			const struct snd_audient_ctrl_type *const ctype,
+			struct snd_audient_cache_entry *const slot,
 			const u8 cidx, u32 *const value)
 {
 	int ret;
 	__le32 buf = 0;
 	s32 val;
 
+	if (slot && slot->valid) {
+		*value = slot->value;
+
+		return ctype->len;
+	}
+
+	/*
+	 * Cached FORCE_SET controls are treated as write-only: an invalid
+	 * cache entry does not trigger a GET.
+	 */
+	if (slot && (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_FORCE_SET))
+		return -ENODATA;
+
 	ret = snd_audient_get_cur(mixer, ctype, cidx, &buf);
 	if (ret < 0)
 		return ret;
@@ -304,43 +340,58 @@ static int snd_audient_raw_get_one(struct usb_mixer_interface *const mixer,
 
 	*value = val;
 
+	if (slot) {
+		slot->value = val;
+		slot->valid = true;
+	}
+
 	return ret;
 }
 
 static int snd_audient_raw_set_one(struct usb_mixer_interface *const mixer,
 			const struct snd_audient_ctrl_type *const ctype,
-			const u8 cidx, const u32 value)
+			struct snd_audient_cache_entry *const slot,
+			const u8 cidx, const u32 value,
+			bool force)
 {
 	int ret;
 	u32 val;
 
-	if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_FORCE_SET) {
+	if (force) {
 		val = !value;		/* just make it different */
 	} else {
-		ret = snd_audient_raw_get_one(mixer, ctype, cidx, &val);
-		if (ret < 0)
+		ret = snd_audient_raw_get_one(mixer, ctype, slot, cidx, &val);
+		if (ret == -ENODATA)	/* FORCED_SET and not cached yet */
+			val = !value;	/* just make it different */
+		else if (ret < 0)
 			return ret;
 	}
 
-	if (val != value) {
+	force = force || (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_FORCE_SET);
+
+	if (force || (val != value)) {
 		__le32 buf = cpu_to_le32(value);
 
 		ret = snd_audient_set_cur(mixer, ctype, cidx, &buf);
 		if (ret < 0)
 			return ret;
 
-		return 1;
+		if (slot) {
+			slot->value = value;
+			slot->valid = true;
+		}
+
 	}
 
-	return 0;
+	return val != value;
 }
 
 
 static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 				       struct snd_ctl_elem_value *ctl_val)
 {
-	struct usb_mixer_elem_list *const list = snd_kcontrol_chip(kctl);
-	struct usb_mixer_interface *const mixer = list->mixer;
+	struct usb_mixer_elem_info *const elem = snd_kcontrol_chip(kctl);
+	struct usb_mixer_interface *const mixer = elem->head.mixer;
 
 	const unsigned int nchan = snd_audient_kctl_channels(kctl);
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
@@ -353,13 +404,19 @@ static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 	CLASS(snd_usb_lock, pm)(mixer->chip);
 	if (pm.err < 0)
 		return pm.err;
+	/* serializes the transfers and the cache, also between gets */
+	guard(mutex)(&mixer->lock);
 
 	for (i = 0; i < hwchan; i++) {
 		u32 buf;
 		int ret;
 
-		ret = snd_audient_raw_get_one(mixer, ctype, base + i, &buf);
-		if (ret < 0)
+		ret = snd_audient_raw_get_one(mixer, ctype,
+					      snd_audient_cache_slot(elem, i),
+					      base + i, &buf);
+		if (ret == -ENODATA)	/* unknown write-only value: off */
+			buf = ctype->min.integer;
+		else if (ret < 0)
 			return ret;
 
 		ctl_val->value.integer.value[i] = (buf == ctype->min.integer)
@@ -375,8 +432,8 @@ static int snd_ctl_audient_boolean_get(struct snd_kcontrol *kctl,
 static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
 				       struct snd_ctl_elem_value *ctl_val)
 {
-	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kctl);
-	struct usb_mixer_interface *mixer = list->mixer;
+	struct usb_mixer_elem_info *const elem = snd_kcontrol_chip(kctl);
+	struct usb_mixer_interface *const mixer = elem->head.mixer;
 
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
 	const struct snd_audient_ctrl_type *const ctype
@@ -389,13 +446,17 @@ static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
 	CLASS(snd_usb_lock, pm)(mixer->chip);
 	if (pm.err < 0)
 		return pm.err;
+	/* serializes the transfers and the cache, also between gets */
+	guard(mutex)(&mixer->lock);
 
 	for (i = 0; i < hwchan; i++) {
 		u32 buf = ctl_val->value.integer.value[i] ? ctype->max.integer
 							  : ctype->min.integer;
 		int ret;
 
-		ret = snd_audient_raw_set_one(mixer, ctype, base + i, buf);
+		ret = snd_audient_raw_set_one(mixer, ctype,
+					      snd_audient_cache_slot(elem, i),
+					      base + i, buf, false);
 		if (ret < 0)
 			return ret;
 
@@ -409,8 +470,8 @@ static int snd_ctl_audient_boolean_set(struct snd_kcontrol *kctl,
 static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 				   struct snd_ctl_elem_value *ctl_val)
 {
-	struct usb_mixer_elem_list *const list = snd_kcontrol_chip(kctl);
-	struct usb_mixer_interface *const mixer = list->mixer;
+	struct usb_mixer_elem_info *const elem = snd_kcontrol_chip(kctl);
+	struct usb_mixer_interface *const mixer = elem->head.mixer;
 
 	const unsigned int nchan = snd_audient_kctl_channels(kctl);
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
@@ -423,13 +484,19 @@ static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 	CLASS(snd_usb_lock, pm)(mixer->chip);
 	if (pm.err < 0)
 		return pm.err;
+	/* serializes the transfers and the cache, also between gets */
+	guard(mutex)(&mixer->lock);
 
 	for (i = 0; i < hwchan; i++) {
 		s32 val;
 		int ret;
 
-		ret = snd_audient_raw_get_one(mixer, ctype, base + i, &val);
-		if (ret < 0)
+		ret = snd_audient_raw_get_one(mixer, ctype,
+					      snd_audient_cache_slot(elem, i),
+					      base + i, &val);
+		if (ret == -ENODATA)	/* unknown write-only value: minimum */
+			val = ctype->min.integer;
+		else if (ret < 0)
 			return ret;
 
 		if (val < ctype->min.integer)
@@ -450,8 +517,8 @@ static int snd_ctl_audient_integer_get(struct snd_kcontrol *kctl,
 static int snd_ctl_audient_integer_set(struct snd_kcontrol *kctl,
 				   struct snd_ctl_elem_value *ctl_val)
 {
-	struct usb_mixer_elem_list *list = snd_kcontrol_chip(kctl);
-	struct usb_mixer_interface *mixer = list->mixer;
+	struct usb_mixer_elem_info *const elem = snd_kcontrol_chip(kctl);
+	struct usb_mixer_interface *mixer = elem->head.mixer;
 
 	const unsigned int hwchan = snd_audient_kctl_hwchannels(kctl);
 	const struct snd_audient_ctrl_type *const ctype
@@ -471,12 +538,16 @@ static int snd_ctl_audient_integer_set(struct snd_kcontrol *kctl,
 	CLASS(snd_usb_lock, pm)(mixer->chip);
 	if (pm.err < 0)
 		return pm.err;
+	/* serializes the transfers and the cache, also between gets */
+	guard(mutex)(&mixer->lock);
 
 	for (i = 0; i < hwchan; i++) {
 		s32 val = ctl_val->value.integer.value[i];
 		int ret;
 
-		ret = snd_audient_raw_set_one(mixer, ctype, base + i, val);
+		ret = snd_audient_raw_set_one(mixer, ctype,
+					      snd_audient_cache_slot(elem, i),
+					      base + i, val, false);
 		if (ret < 0)
 			return ret;
 
@@ -517,6 +588,8 @@ static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
 	struct snd_kcontrol *kctl;
 	struct usb_mixer_elem_info *elem;
 
+	int ret;
+
 	knew.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
 	knew.name = ctrl->name;
 	knew.info = snd_ctl_audient_info;
@@ -524,7 +597,9 @@ static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
 						   ctrl->hwchannels);
 	knew.tlv.p = ctype->tlv;
 	knew.access = SNDRV_CTL_ELEM_ACCESS_READWRITE
-			| SNDRV_CTL_ELEM_ACCESS_VOLATILE
+			| ((ctype->flags & SND_AUDIENT_CTYPE_FLAGS_CACHE)
+			   ? 0
+			   : SNDRV_CTL_ELEM_ACCESS_VOLATILE)
 			| (ctype->tlv ? SNDRV_CTL_ELEM_ACCESS_TLV_READ : 0);
 
 	switch (ctype->type) {
@@ -540,36 +615,75 @@ static int snd_audient_add_ctrl(struct usb_mixer_interface *mixer,
 		return -EINVAL;
 	}
 
+	elem = kzalloc(sizeof(*elem)
+		       + ((ctype->flags & SND_AUDIENT_CTYPE_FLAGS_CACHE)
+			  ? (sizeof(struct snd_audient_cache_entry)
+			     * ctrl->hwchannels)
+			  : 0),
+		       GFP_KERNEL);
+	if (!elem)
+		return -ENOMEM;
+
+	elem->head.mixer = mixer;
+	elem->channels = ctrl->channels;
+
+	if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_CACHE)
+		elem->private_data = elem + 1;
+
+	/*
+	 * A failed probe transfer must not fail the card: warn and keep the
+	 * control. Its cache entry stays invalid, so a readable control reads
+	 * the device again on its next get, and a write-only control shows an
+	 * unknown value until a put succeeds.
+	 */
 	if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_INIT_HW) {
 		int i;
 
 		for (i = 0; i < ctrl->hwchannels; i++) {
-			int ret = snd_audient_raw_set_one(mixer, ctype,
-							  ctrl->val_offs + i,
-							  ctype->init);
+			ret = snd_audient_raw_set_one(mixer, ctype,
+						      snd_audient_cache_slot(elem, i),
+						      ctrl->val_offs + i,
+						      ctype->init, true);
 			if (ret < 0)
 				usb_audio_warn(mixer->chip,
 					       "%s: cannot set channel %d (%d)\n",
 					       ctrl->name, i, ret);
 		}
-	}
-
-	elem = kzalloc_obj(*elem);
-	if (!elem)
-		return -ENOMEM;
+	} else if (elem->private_data) {
+		struct snd_audient_cache_entry *const cache = elem->private_data;
+		int i;
 
-	elem->head.mixer = mixer;
-	elem->channels = ctrl->channels;
+		for (i = 0; i < ctrl->hwchannels; i++) {
+			if (ctype->flags & SND_AUDIENT_CTYPE_FLAGS_FORCE_SET) {
+				cache[i].value = ctype->init;
+				cache[i].valid = true;
+				continue;
+			}
+
+			ret = snd_audient_raw_get_one(mixer, ctype, cache + i,
+						      ctrl->val_offs + i,
+						      &cache[i].value);
+			if (ret < 0)
+				usb_audio_warn(mixer->chip,
+					       "%s: cannot read channel %d (%d)\n",
+					       ctrl->name, i, ret);
+		}
+	}
 
 	kctl = snd_ctl_new1(&knew, elem);
 	if (!kctl) {
-		kfree(elem);
-		return -ENOMEM;
+		ret = -ENOMEM;
+		goto free_elem;
 	}
 
 	kctl->private_free = snd_usb_mixer_elem_free;
 
 	return snd_usb_mixer_add_control(&elem->head, kctl);
+
+free_elem:
+	kfree(elem);
+
+	return ret;
 }
 
 
-- 
2.56.0

[RFC V2 PATCH 11/11] ALSA: mixer_audient: Create matrix programmatically

[Christian Ruppert]

Most Audient devices seem to have a similar mixer matrix with many
identical channels. The only difference between devices seems to be
the matrix' dimension. Create it programmatically in a loop rather
than from the controls table.

Signed-off-by: Christian Ruppert <arc@gmx.li>
Co-developed-by: Will Porter <mrwillporter@gmail.com>
Signed-off-by: Will Porter <mrwillporter@gmail.com>
Assisted-by: Claude:claude-opus-5-5
---
 sound/usb/mixer_audient.c | 77 +++++++++++++++++----------------------
 1 file changed, 34 insertions(+), 43 deletions(-)

diff --git a/sound/usb/mixer_audient.c b/sound/usb/mixer_audient.c
index 856fb669af3f..483ab8fe6109 100644
--- a/sound/usb/mixer_audient.c
+++ b/sound/usb/mixer_audient.c
@@ -105,7 +105,7 @@ static const struct snd_audient_ctrl_type {
 
 
 struct snd_audient_ctrl {
-	char *name;
+	const char *const name;
 	enum snd_audient_type type;
 	unsigned int channels;
 	unsigned int hwchannels;
@@ -134,48 +134,6 @@ static const struct snd_audient_ctrl snd_audient_evo4_controls[] = {
 		.hwchannels = 1,
 		.val_offs = 0,
 	},
-	{
-		.name = "Mic 1 Capture Volume",
-		.type = SND_AUDIENT_TYPE_MIXER,
-		.channels = 2,
-		.hwchannels = 2,
-		.val_offs = 0,
-	},
-	{
-		.name = "Mic 2 Capture Volume",
-		.type = SND_AUDIENT_TYPE_MIXER,
-		.channels = 2,
-		.hwchannels = 2,
-		.val_offs = 2,
-	},
-	{
-		.name = "Master Left Capture Volume",
-		.type = SND_AUDIENT_TYPE_MIXER,
-		.channels = 2,
-		.hwchannels = 2,
-		.val_offs = 4,
-	},
-	{
-		.name = "Master Right Capture Volume",
-		.type = SND_AUDIENT_TYPE_MIXER,
-		.channels = 2,
-		.hwchannels = 2,
-		.val_offs = 6,
-	},
-	{
-		.name = "Loopback Left Capture Volume",
-		.type = SND_AUDIENT_TYPE_MIXER,
-		.channels = 2,
-		.hwchannels = 2,
-		.val_offs = 8,
-	},
-	{
-		.name = "Loopback Right Capture Volume",
-		.type = SND_AUDIENT_TYPE_MIXER,
-		.channels = 2,
-		.hwchannels = 2,
-		.val_offs = 10,
-	},
 	{
 		.name = "Mic 1 Phantom Capture Switch",
 		.type = SND_AUDIENT_TYPE_PHANTOM,
@@ -193,13 +151,27 @@ static const struct snd_audient_ctrl snd_audient_evo4_controls[] = {
 	{ 0 }, /* sentinel */
 };
 
+static const char *const snd_audient_evo4_matrix[] = {
+	"Mic 1 Capture Volume",
+	"Mic 2 Capture Volume",
+	"Master Left Capture Volume",
+	"Master Right Capture Volume",
+	"Loopback Left Capture Volume",
+	"Loopback Right Capture Volume",
+	NULL
+};
+
 static const struct audient_devinfo {
 	u32 usb_id;
 	const struct snd_audient_ctrl *controls;
+	const char *const *const matrix_names;
+	const unsigned int matrix_channels;
 } audient_devinfo[] = {
 	{
 		.usb_id = USB_ID(USB_AUDIENT_VID, USB_EVO4_PID),
 		.controls = snd_audient_evo4_controls,
+		.matrix_names = snd_audient_evo4_matrix,
+		.matrix_channels = 2,
 	},
 	{ 0 } /* sentinel */
 };
@@ -693,6 +665,8 @@ int snd_audient_controls_create(struct usb_mixer_interface *mixer)
 	const struct audient_devinfo *info;
 	const struct snd_audient_ctrl *ctrl;
 
+	int i;
+
 	for (info = audient_devinfo; info->controls; info++)
 		if (info->usb_id == mixer->chip->usb_id)
 			break;
@@ -707,5 +681,22 @@ int snd_audient_controls_create(struct usb_mixer_interface *mixer)
 			return ret;
 	}
 
+	if (info->matrix_names) {
+		for (i = 0; info->matrix_names[i]; i++) {
+			const struct snd_audient_ctrl c = {
+				.name = info->matrix_names[i],
+				.type = SND_AUDIENT_TYPE_MIXER,
+				.channels = info->matrix_channels,
+				.hwchannels = info->matrix_channels,
+				.val_offs = i * info->matrix_channels,
+			};
+
+			const int ret = snd_audient_add_ctrl(mixer, &c);
+
+			if (ret < 0)
+				return ret;
+		}
+	}
+
 	return 0;
 }
-- 
2.56.0