[PATCH v2 0/9] iio: ad3552r-hs: add support for ad3541/42r

[PATCH v2 0/9] iio: ad3552r-hs: add support for ad3541/42r

[Angelo Dureghello]

This patchset add support for ad3541/42r, 16MUPS, respectively
single and dual channel DACs, together with some minor fixes.

The ad354xr connect through a DSPI bus (while ad355xr through
QSPI), so a new fpga HDL supporting bus mode switch has been
developed to support them.

Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
---
Changes in v2:
- reproposing the patchset using platform data for bus mode
  change functionality,
- improve commit messages,
- add separate patch for instruction mode,
- add separate patch for sharing model data structures,
- remove error on wrong id,
- fix id detection info message in case of wrong id.

---
Angelo Dureghello (9):
      iio: dac: ad3552r-common: fix ad3541/2r ranges
      iio: dac: ad3552r-hs: clear reset status flag
      iio: dac: adi-axi-dac: modify stream enable
      iio: dac: adi-axi-dac: add bus mode setup
      iio: dac: ad3552r-hs: fix message on wrong chip id
      iio: dac: ad3552r-hs: use instruction mode for configuration
      iio: dac: ad3552r: share model data structures
      iio: dac: ad3552r-hs: add ad3541/2r support
      iio: dac: ad3552r-hs: update function name (non functional)

 drivers/iio/dac/ad3552r-common.c |  49 ++++++-
 drivers/iio/dac/ad3552r-hs.c     | 303 ++++++++++++++++++++++++++++++---------
 drivers/iio/dac/ad3552r-hs.h     |   8 ++
 drivers/iio/dac/ad3552r.c        |  36 -----
 drivers/iio/dac/ad3552r.h        |  16 ++-
 drivers/iio/dac/adi-axi-dac.c    |  37 ++++-
 6 files changed, 339 insertions(+), 110 deletions(-)
---
base-commit: 5f8c6f117400b7b21ad248959ae2cb6e0d634e97
change-id: 20250108-wip-bl-ad3552r-axi-v0-iio-testing-carlos-9fae2ab88a12

Best regards,
-- 
Angelo Dureghello <adureghello@baylibre.com>

[PATCH v2 1/9] iio: dac: ad3552r-common: fix ad3541/2r ranges

[Angelo Dureghello]

From: Angelo Dureghello <adureghello@baylibre.com>

Fix ad3541/2r voltage ranges to be as per ad3542r datasheet,
rev. C, table 38 (page 57).

The wrong ad354xr ranges was generating erroneous Vpp output.

In more details:
- fix wrong number of ranges, they are 5 ranges, not 6,
- remove non-existent 0-3V range,
- adjust order, since ad3552r_find_range() get a wrong index,
  producing a wrong Vpp as output.

Retested all the ranges on real hardware, EVALAD3542RFMCZ:

adi,output-range-microvolt (fdt):
<(000000) (2500000)>;   ok (Rfbx1, switch 10)
<(000000) (5000000)>;   ok (Rfbx1, switch 10)
<(000000) (10000000)>;  ok (Rfbx1, switch 10)
<(-5000000) (5000000)>; ok (Rfbx2, switch +/- 5)
<(-2500000) (7500000)>; ok (Rfbx2, switch -2.5/7.5)

Fixes: 8f2b54824b28 ("drivers:iio:dac: Add AD3552R driver support")
Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
---
 drivers/iio/dac/ad3552r-common.c | 5 ++---
 drivers/iio/dac/ad3552r.h        | 8 +++-----
 2 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/drivers/iio/dac/ad3552r-common.c b/drivers/iio/dac/ad3552r-common.c
index 0f495df2e5ce..03e0864f5084 100644
--- a/drivers/iio/dac/ad3552r-common.c
+++ b/drivers/iio/dac/ad3552r-common.c
@@ -22,11 +22,10 @@ EXPORT_SYMBOL_NS_GPL(ad3552r_ch_ranges, "IIO_AD3552R");
 
 const s32 ad3542r_ch_ranges[AD3542R_MAX_RANGES][2] = {
 	[AD3542R_CH_OUTPUT_RANGE_0__2P5V]	= { 0, 2500 },
-	[AD3542R_CH_OUTPUT_RANGE_0__3V]		= { 0, 3000 },
 	[AD3542R_CH_OUTPUT_RANGE_0__5V]		= { 0, 5000 },
 	[AD3542R_CH_OUTPUT_RANGE_0__10V]	= { 0, 10000 },
-	[AD3542R_CH_OUTPUT_RANGE_NEG_2P5__7P5V]	= { -2500, 7500 },
-	[AD3542R_CH_OUTPUT_RANGE_NEG_5__5V]	= { -5000, 5000 }
+	[AD3542R_CH_OUTPUT_RANGE_NEG_5__5V]	= { -5000, 5000 },
+	[AD3542R_CH_OUTPUT_RANGE_NEG_2P5__7P5V]	= { -2500, 7500 }
 };
 EXPORT_SYMBOL_NS_GPL(ad3542r_ch_ranges, "IIO_AD3552R");
 
diff --git a/drivers/iio/dac/ad3552r.h b/drivers/iio/dac/ad3552r.h
index fd5a3dfd1d1c..4b5581039ae9 100644
--- a/drivers/iio/dac/ad3552r.h
+++ b/drivers/iio/dac/ad3552r.h
@@ -131,7 +131,7 @@
 #define AD3552R_CH1_ACTIVE				BIT(1)
 
 #define AD3552R_MAX_RANGES	5
-#define AD3542R_MAX_RANGES	6
+#define AD3542R_MAX_RANGES	5
 #define AD3552R_QUAD_SPI	2
 
 extern const s32 ad3552r_ch_ranges[AD3552R_MAX_RANGES][2];
@@ -189,16 +189,14 @@ enum ad3552r_ch_vref_select {
 enum ad3542r_ch_output_range {
 	/* Range from 0 V to 2.5 V. Requires Rfb1x connection */
 	AD3542R_CH_OUTPUT_RANGE_0__2P5V,
-	/* Range from 0 V to 3 V. Requires Rfb1x connection  */
-	AD3542R_CH_OUTPUT_RANGE_0__3V,
 	/* Range from 0 V to 5 V. Requires Rfb1x connection  */
 	AD3542R_CH_OUTPUT_RANGE_0__5V,
 	/* Range from 0 V to 10 V. Requires Rfb2x connection  */
 	AD3542R_CH_OUTPUT_RANGE_0__10V,
-	/* Range from -2.5 V to 7.5 V. Requires Rfb2x connection  */
-	AD3542R_CH_OUTPUT_RANGE_NEG_2P5__7P5V,
 	/* Range from -5 V to 5 V. Requires Rfb2x connection  */
 	AD3542R_CH_OUTPUT_RANGE_NEG_5__5V,
+	/* Range from -2.5 V to 7.5 V. Requires Rfb2x connection  */
+	AD3542R_CH_OUTPUT_RANGE_NEG_2P5__7P5V,
 };
 
 enum ad3552r_ch_output_range {

-- 
2.47.0

[PATCH v2 2/9] iio: dac: ad3552r-hs: clear reset status flag

[Angelo Dureghello]

From: Angelo Dureghello <adureghello@baylibre.com>

Clear reset status flag, to keep error status register
clean after reset (ad3552r manual, rev B table 38).

Reset error flag was left to 1, so debugging registers, the
"Error Status Register" was dirty (0x01). It is important
to clear this bit, so if there is any reset event over normal
working mode, it is possible to detect it.

Fixes: 0b4d9fe58be8 ("iio: dac: ad3552r: add high-speed platform driver")
Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
---
 drivers/iio/dac/ad3552r-hs.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c
index 216c634f3eaf..8974df625670 100644
--- a/drivers/iio/dac/ad3552r-hs.c
+++ b/drivers/iio/dac/ad3552r-hs.c
@@ -329,6 +329,12 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
 		dev_info(st->dev, "Chip ID error. Expected 0x%x, Read 0x%x\n",
 			 AD3552R_ID, id);
 
+	/* Clear reset error flag, see ad3552r manual, rev B table 38. */
+	ret = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_ERR_STATUS,
+				      AD3552R_MASK_RESET_STATUS, 1);
+	if (ret)
+		return ret;
+
 	ret = st->data->bus_reg_write(st->back,
 				      AD3552R_REG_ADDR_SH_REFERENCE_CONFIG,
 				      0, 1);

-- 
2.47.0

[PATCH v2 3/9] iio: dac: adi-axi-dac: modify stream enable

[Angelo Dureghello]

From: Angelo Dureghello <adureghello@baylibre.com>

Change suggested from the AXI HDL team, modify the function
axi_dac_data_stream_enable() to check for interface busy, to avoid
possible issues when starting the stream.

Fixes: e61d7178429a ("iio: dac: adi-axi-dac: extend features")
Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
---
 drivers/iio/dac/adi-axi-dac.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/iio/dac/adi-axi-dac.c b/drivers/iio/dac/adi-axi-dac.c
index b143f7ed6847..d02eb535b648 100644
--- a/drivers/iio/dac/adi-axi-dac.c
+++ b/drivers/iio/dac/adi-axi-dac.c
@@ -585,6 +585,17 @@ static int axi_dac_ddr_disable(struct iio_backend *back)
 static int axi_dac_data_stream_enable(struct iio_backend *back)
 {
 	struct axi_dac_state *st = iio_backend_get_priv(back);
+	int ret, val;
+
+	ret = regmap_read_poll_timeout(st->regmap,
+				AXI_DAC_UI_STATUS_REG, val,
+				FIELD_GET(AXI_DAC_UI_STATUS_IF_BUSY, val) == 0,
+				10, 100 * KILO);
+	if (ret) {
+		if (ret == -ETIMEDOUT)
+			dev_err(st->dev, "AXI read timeout\n");
+		return ret;
+	}
 
 	return regmap_set_bits(st->regmap, AXI_DAC_CUSTOM_CTRL_REG,
 			       AXI_DAC_CUSTOM_CTRL_STREAM_ENABLE);

-- 
2.47.0

[PATCH v2 4/9] iio: dac: adi-axi-dac: add bus mode setup

[Angelo Dureghello]

From: Angelo Dureghello <adureghello@baylibre.com>

The ad354xr requires DSPI mode (2 data lanes) to work in buffering
mode, so backend needs to allow a mode selection between:
    SPI  (entire ad35xxr family),
    DSPI (ad354xr),
    QSPI (ad355xr).

Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
---
 drivers/iio/dac/ad3552r-hs.h  |  8 ++++++++
 drivers/iio/dac/adi-axi-dac.c | 26 +++++++++++++++++++++++++-
 2 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/dac/ad3552r-hs.h b/drivers/iio/dac/ad3552r-hs.h
index 724261d38dea..4a9e35234124 100644
--- a/drivers/iio/dac/ad3552r-hs.h
+++ b/drivers/iio/dac/ad3552r-hs.h
@@ -8,11 +8,19 @@
 
 struct iio_backend;
 
+enum ad3552r_io_mode {
+	AD3552R_IO_MODE_SPI,
+	AD3552R_IO_MODE_DSPI,
+	AD3552R_IO_MODE_QSPI,
+};
+
 struct ad3552r_hs_platform_data {
 	int (*bus_reg_read)(struct iio_backend *back, u32 reg, u32 *val,
 			    size_t data_size);
 	int (*bus_reg_write)(struct iio_backend *back, u32 reg, u32 val,
 			     size_t data_size);
+	int (*bus_set_io_mode)(struct iio_backend *back,
+			       enum ad3552r_io_mode mode);
 	u32 bus_sample_data_clock_hz;
 };
 
diff --git a/drivers/iio/dac/adi-axi-dac.c b/drivers/iio/dac/adi-axi-dac.c
index d02eb535b648..79ca158c1ad9 100644
--- a/drivers/iio/dac/adi-axi-dac.c
+++ b/drivers/iio/dac/adi-axi-dac.c
@@ -64,7 +64,7 @@
 #define   AXI_DAC_UI_STATUS_IF_BUSY		BIT(4)
 #define AXI_DAC_CUSTOM_CTRL_REG			0x008C
 #define   AXI_DAC_CUSTOM_CTRL_ADDRESS		GENMASK(31, 24)
-#define   AXI_DAC_CUSTOM_CTRL_SYNCED_TRANSFER	BIT(2)
+#define   AXI_DAC_CUSTOM_CTRL_MULTI_IO_MODE	GENMASK(3, 2)
 #define   AXI_DAC_CUSTOM_CTRL_STREAM		BIT(1)
 #define   AXI_DAC_CUSTOM_CTRL_TRANSFER_DATA	BIT(0)
 
@@ -725,6 +725,29 @@ static int axi_dac_bus_reg_read(struct iio_backend *back, u32 reg, u32 *val,
 	return regmap_read(st->regmap, AXI_DAC_CUSTOM_RD_REG, val);
 }
 
+static int axi_dac_bus_set_io_mode(struct iio_backend *back,
+				   enum ad3552r_io_mode mode)
+{
+	struct axi_dac_state *st = iio_backend_get_priv(back);
+	int ival, ret;
+
+	ret = regmap_update_bits(st->regmap, AXI_DAC_CUSTOM_CTRL_REG,
+				 AXI_DAC_CUSTOM_CTRL_MULTI_IO_MODE,
+				 FIELD_PREP(AXI_DAC_CUSTOM_CTRL_MULTI_IO_MODE, mode));
+	if (ret)
+		return ret;
+
+	ret = regmap_read_poll_timeout(st->regmap,
+				       AXI_DAC_UI_STATUS_REG, ival,
+				       FIELD_GET(AXI_DAC_UI_STATUS_IF_BUSY, ival) == 0,
+				       10, 100 * KILO);
+
+	if (ret == -ETIMEDOUT)
+		dev_err(st->dev, "AXI read timeout\n");
+
+	return ret;
+}
+
 static void axi_dac_child_remove(void *data)
 {
 	platform_device_unregister(data);
@@ -736,6 +759,7 @@ static int axi_dac_create_platform_device(struct axi_dac_state *st,
 	struct ad3552r_hs_platform_data pdata = {
 		.bus_reg_read = axi_dac_bus_reg_read,
 		.bus_reg_write = axi_dac_bus_reg_write,
+		.bus_set_io_mode = axi_dac_bus_set_io_mode,
 		.bus_sample_data_clock_hz = st->dac_clk_rate,
 	};
 	struct platform_device_info pi = {

-- 
2.47.0

[PATCH v2 5/9] iio: dac: ad3552r-hs: fix message on wrong chip id

[Angelo Dureghello]

From: Angelo Dureghello <adureghello@baylibre.com>

Set a better info message on wrong chip id, fixing the
expected value as read from the info struct.

Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
---
 drivers/iio/dac/ad3552r-hs.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c
index 8974df625670..27949f207d42 100644
--- a/drivers/iio/dac/ad3552r-hs.c
+++ b/drivers/iio/dac/ad3552r-hs.c
@@ -326,8 +326,9 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
 
 	id |= val << 8;
 	if (id != st->model_data->chip_id)
-		dev_info(st->dev, "Chip ID error. Expected 0x%x, Read 0x%x\n",
-			 AD3552R_ID, id);
+		dev_info(st->dev,
+			 "Chip ID mismatch, detected 0x%x but expected 0x%x\n",
+			 id, st->model_data->chip_id);
 
 	/* Clear reset error flag, see ad3552r manual, rev B table 38. */
 	ret = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_ERR_STATUS,

-- 
2.47.0

[PATCH v2 6/9] iio: dac: ad3552r-hs: use instruction mode for configuration

[Angelo Dureghello]

From: Angelo Dureghello <adureghello@baylibre.com>

Use "instruction" mode over initial configuration and all other
non-streaming operations.

DAC boots in streaming mode as default, and the driver is not
changing this mode.

Instruction r/w is still working becouse instruction is processed
from the DAC after chip select is deasserted, this works until
loop mode is 0 or greater than the instruction size.

All initial operations should be more safely done in instruction
mode, a mode provided for this.

Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
---
 drivers/iio/dac/ad3552r-hs.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c
index 27949f207d42..991b11702273 100644
--- a/drivers/iio/dac/ad3552r-hs.c
+++ b/drivers/iio/dac/ad3552r-hs.c
@@ -132,6 +132,13 @@ static int ad3552r_hs_buffer_postenable(struct iio_dev *indio_dev)
 		return -EINVAL;
 	}
 
+	/* Primary region access, set streaming mode (now in SPI + SDR). */
+	ret = ad3552r_qspi_update_reg_bits(st,
+					   AD3552R_REG_ADDR_INTERFACE_CONFIG_B,
+					   AD3552R_MASK_SINGLE_INST, 0, 1);
+	if (ret)
+		return ret;
+
 	ret = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_STREAM_MODE,
 				      loop_len, 1);
 	if (ret)
@@ -198,6 +205,14 @@ static int ad3552r_hs_buffer_predisable(struct iio_dev *indio_dev)
 	if (ret)
 		return ret;
 
+	/* Back to single instruction mode, disabling loop. */
+	ret = ad3552r_qspi_update_reg_bits(st,
+					   AD3552R_REG_ADDR_INTERFACE_CONFIG_B,
+					   AD3552R_MASK_SINGLE_INST,
+					   AD3552R_MASK_SINGLE_INST, 1);
+	if (ret)
+		return ret;
+
 	return 0;
 }
 
@@ -308,6 +323,13 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
 	if (ret)
 		return ret;
 
+	ret = st->data->bus_reg_write(st->back,
+				      AD3552R_REG_ADDR_INTERFACE_CONFIG_B,
+				      AD3552R_MASK_SINGLE_INST |
+				      AD3552R_MASK_SHORT_INSTRUCTION, 1);
+	if (ret)
+		return ret;
+
 	ret = ad3552r_hs_scratch_pad_test(st);
 	if (ret)
 		return ret;

-- 
2.47.0

[PATCH v2 7/9] iio: dac: ad3552r: share model data structures

[Angelo Dureghello]

From: Angelo Dureghello <adureghello@baylibre.com>

Preparing for new parts to be added also in the hs driver,
set model data structures in ad3552r-common.c, to be accessible
from both -hs and non hs driver.

Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
---
 drivers/iio/dac/ad3552r-common.c | 40 ++++++++++++++++++++++++++++++++++++++++
 drivers/iio/dac/ad3552r-hs.c     |  8 --------
 drivers/iio/dac/ad3552r.c        | 36 ------------------------------------
 drivers/iio/dac/ad3552r.h        |  5 +++++
 4 files changed, 45 insertions(+), 44 deletions(-)

diff --git a/drivers/iio/dac/ad3552r-common.c b/drivers/iio/dac/ad3552r-common.c
index 03e0864f5084..36920ec95836 100644
--- a/drivers/iio/dac/ad3552r-common.c
+++ b/drivers/iio/dac/ad3552r-common.c
@@ -37,6 +37,46 @@ static const s32 gains_scaling_table[] = {
 	[AD3552R_CH_GAIN_SCALING_0_125]		= 125
 };
 
+const struct ad3552r_model_data ad3541r_model_data = {
+	.model_name = "ad3541r",
+	.chip_id = AD3541R_ID,
+	.num_hw_channels = 1,
+	.ranges_table = ad3542r_ch_ranges,
+	.num_ranges = ARRAY_SIZE(ad3542r_ch_ranges),
+	.requires_output_range = true,
+};
+EXPORT_SYMBOL_NS_GPL(ad3541r_model_data, "IIO_AD3552R");
+
+const struct ad3552r_model_data ad3542r_model_data = {
+	.model_name = "ad3542r",
+	.chip_id = AD3542R_ID,
+	.num_hw_channels = 2,
+	.ranges_table = ad3542r_ch_ranges,
+	.num_ranges = ARRAY_SIZE(ad3542r_ch_ranges),
+	.requires_output_range = true,
+};
+EXPORT_SYMBOL_NS_GPL(ad3542r_model_data, "IIO_AD3552R");
+
+const struct ad3552r_model_data ad3551r_model_data = {
+	.model_name = "ad3551r",
+	.chip_id = AD3551R_ID,
+	.num_hw_channels = 1,
+	.ranges_table = ad3552r_ch_ranges,
+	.num_ranges = ARRAY_SIZE(ad3552r_ch_ranges),
+	.requires_output_range = false,
+};
+EXPORT_SYMBOL_NS_GPL(ad3551r_model_data, "IIO_AD3552R");
+
+const struct ad3552r_model_data ad3552r_model_data = {
+	.model_name = "ad3552r",
+	.chip_id = AD3552R_ID,
+	.num_hw_channels = 2,
+	.ranges_table = ad3552r_ch_ranges,
+	.num_ranges = ARRAY_SIZE(ad3552r_ch_ranges),
+	.requires_output_range = false,
+};
+EXPORT_SYMBOL_NS_GPL(ad3552r_model_data, "IIO_AD3552R");
+
 u16 ad3552r_calc_custom_gain(u8 p, u8 n, s16 goffs)
 {
 	return FIELD_PREP(AD3552R_MASK_CH_RANGE_OVERRIDE, 1) |
diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c
index 991b11702273..bfb6228c9b9b 100644
--- a/drivers/iio/dac/ad3552r-hs.c
+++ b/drivers/iio/dac/ad3552r-hs.c
@@ -527,14 +527,6 @@ static int ad3552r_hs_probe(struct platform_device *pdev)
 	return devm_iio_device_register(&pdev->dev, indio_dev);
 }
 
-static const struct ad3552r_model_data ad3552r_model_data = {
-	.model_name = "ad3552r",
-	.chip_id = AD3552R_ID,
-	.num_hw_channels = 2,
-	.ranges_table = ad3552r_ch_ranges,
-	.num_ranges = ARRAY_SIZE(ad3552r_ch_ranges),
-};
-
 static const struct of_device_id ad3552r_hs_of_id[] = {
 	{ .compatible = "adi,ad3552r", .data = &ad3552r_model_data },
 	{ }
diff --git a/drivers/iio/dac/ad3552r.c b/drivers/iio/dac/ad3552r.c
index e7206af53af6..9d28e06b80c0 100644
--- a/drivers/iio/dac/ad3552r.c
+++ b/drivers/iio/dac/ad3552r.c
@@ -649,42 +649,6 @@ static int ad3552r_probe(struct spi_device *spi)
 	return devm_iio_device_register(&spi->dev, indio_dev);
 }
 
-static const struct ad3552r_model_data ad3541r_model_data = {
-	.model_name = "ad3541r",
-	.chip_id = AD3541R_ID,
-	.num_hw_channels = 1,
-	.ranges_table = ad3542r_ch_ranges,
-	.num_ranges = ARRAY_SIZE(ad3542r_ch_ranges),
-	.requires_output_range = true,
-};
-
-static const struct ad3552r_model_data ad3542r_model_data = {
-	.model_name = "ad3542r",
-	.chip_id = AD3542R_ID,
-	.num_hw_channels = 2,
-	.ranges_table = ad3542r_ch_ranges,
-	.num_ranges = ARRAY_SIZE(ad3542r_ch_ranges),
-	.requires_output_range = true,
-};
-
-static const struct ad3552r_model_data ad3551r_model_data = {
-	.model_name = "ad3551r",
-	.chip_id = AD3551R_ID,
-	.num_hw_channels = 1,
-	.ranges_table = ad3552r_ch_ranges,
-	.num_ranges = ARRAY_SIZE(ad3552r_ch_ranges),
-	.requires_output_range = false,
-};
-
-static const struct ad3552r_model_data ad3552r_model_data = {
-	.model_name = "ad3552r",
-	.chip_id = AD3552R_ID,
-	.num_hw_channels = 2,
-	.ranges_table = ad3552r_ch_ranges,
-	.num_ranges = ARRAY_SIZE(ad3552r_ch_ranges),
-	.requires_output_range = false,
-};
-
 static const struct spi_device_id ad3552r_id[] = {
 	{
 		.name = "ad3541r",
diff --git a/drivers/iio/dac/ad3552r.h b/drivers/iio/dac/ad3552r.h
index 4b5581039ae9..23f038464a0c 100644
--- a/drivers/iio/dac/ad3552r.h
+++ b/drivers/iio/dac/ad3552r.h
@@ -137,6 +137,11 @@
 extern const s32 ad3552r_ch_ranges[AD3552R_MAX_RANGES][2];
 extern const s32 ad3542r_ch_ranges[AD3542R_MAX_RANGES][2];
 
+extern const struct ad3552r_model_data ad3541r_model_data;
+extern const struct ad3552r_model_data ad3542r_model_data;
+extern const struct ad3552r_model_data ad3551r_model_data;
+extern const struct ad3552r_model_data ad3552r_model_data;
+
 enum ad3552r_id {
 	AD3541R_ID = 0x400b,
 	AD3542R_ID = 0x4009,

-- 
2.47.0

[PATCH v2 8/9] iio: dac: ad3552r-hs: add ad3541/2r support

[Angelo Dureghello]

From: Angelo Dureghello <adureghello@baylibre.com>

A new fpga HDL has been developed from ADI to support ad354xr
devices.

Add support for ad3541r and ad3542r with following additions:

- use common device_info structures for hs and non hs drivers,
- DMA buffering, use DSPI mode for ad354xr and QSPI for ad355xr,
- change samplerate to respect number of lanes.

Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
---
 drivers/iio/dac/ad3552r-common.c |   4 +
 drivers/iio/dac/ad3552r-hs.c     | 240 ++++++++++++++++++++++++++++++++-------
 drivers/iio/dac/ad3552r.h        |   3 +
 3 files changed, 206 insertions(+), 41 deletions(-)

diff --git a/drivers/iio/dac/ad3552r-common.c b/drivers/iio/dac/ad3552r-common.c
index 36920ec95836..fa3050dc2efa 100644
--- a/drivers/iio/dac/ad3552r-common.c
+++ b/drivers/iio/dac/ad3552r-common.c
@@ -44,6 +44,7 @@ const struct ad3552r_model_data ad3541r_model_data = {
 	.ranges_table = ad3542r_ch_ranges,
 	.num_ranges = ARRAY_SIZE(ad3542r_ch_ranges),
 	.requires_output_range = true,
+	.num_spi_data_lanes = 2,
 };
 EXPORT_SYMBOL_NS_GPL(ad3541r_model_data, "IIO_AD3552R");
 
@@ -54,6 +55,7 @@ const struct ad3552r_model_data ad3542r_model_data = {
 	.ranges_table = ad3542r_ch_ranges,
 	.num_ranges = ARRAY_SIZE(ad3542r_ch_ranges),
 	.requires_output_range = true,
+	.num_spi_data_lanes = 2,
 };
 EXPORT_SYMBOL_NS_GPL(ad3542r_model_data, "IIO_AD3552R");
 
@@ -64,6 +66,7 @@ const struct ad3552r_model_data ad3551r_model_data = {
 	.ranges_table = ad3552r_ch_ranges,
 	.num_ranges = ARRAY_SIZE(ad3552r_ch_ranges),
 	.requires_output_range = false,
+	.num_spi_data_lanes = 4,
 };
 EXPORT_SYMBOL_NS_GPL(ad3551r_model_data, "IIO_AD3552R");
 
@@ -74,6 +77,7 @@ const struct ad3552r_model_data ad3552r_model_data = {
 	.ranges_table = ad3552r_ch_ranges,
 	.num_ranges = ARRAY_SIZE(ad3552r_ch_ranges),
 	.requires_output_range = false,
+	.num_spi_data_lanes = 4,
 };
 EXPORT_SYMBOL_NS_GPL(ad3552r_model_data, "IIO_AD3552R");
 
diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c
index bfb6228c9b9b..5995bab6a9b1 100644
--- a/drivers/iio/dac/ad3552r-hs.c
+++ b/drivers/iio/dac/ad3552r-hs.c
@@ -19,6 +19,31 @@
 #include "ad3552r.h"
 #include "ad3552r-hs.h"
 
+/*
+ * Important notes for register map access:
+ * ========================================
+ *
+ * Register address space is divided in 2 regions, primary (config) and
+ * secondary (DAC). Primary region can only be accessed in simple SPI mode,
+ * with exception for ad355x models where setting QSPI pin high allows QSPI
+ * access to both the regions.
+ *
+ * Due to the fact that ad3541/2r do not implement QSPI, for proper device
+ * detection, HDL keeps "QSPI" pin level low at boot (see ad3552r manual, rev B
+ * table 7, pin 31, digital input). For this reason, actually the working mode
+ * between SPI, DSPI and QSPI must be set via software, configuring the target
+ * DAC appropriately, together with the backend api to configure the bus mode
+ * accordingly.
+ *
+ * Also, important to note that none of the three modes allow to read in DDR.
+ *
+ * In non-buffering operations, mode is set to simple SPI SDR for all primary
+ * and secondary region r/w accesses, to avoid to switch the mode each time DAC
+ * register is accessed (raw accesses, r/w), and to be able to dump registers
+ * content (possible as non DDR only).
+ * In buffering mode, driver sets best possible mode, D/QSPI and DDR.
+ */
+
 struct ad3552r_hs_state {
 	const struct ad3552r_model_data *model_data;
 	struct gpio_desc *reset_gpio;
@@ -27,6 +52,8 @@ struct ad3552r_hs_state {
 	bool single_channel;
 	struct ad3552r_ch_data ch_data[AD3552R_MAX_CH];
 	struct ad3552r_hs_platform_data *data;
+	/* INTERFACE_CONFIG_D register cache, in DDR we cannot read values. */
+	u32 config_d;
 };
 
 static int ad3552r_qspi_update_reg_bits(struct ad3552r_hs_state *st,
@@ -56,15 +83,19 @@ static int ad3552r_hs_read_raw(struct iio_dev *indio_dev,
 	switch (mask) {
 	case IIO_CHAN_INFO_SAMP_FREQ:
 		/*
-		 * Using 4 lanes (QSPI), then using 2 as DDR mode is
-		 * considered always on (considering buffering mode always).
+		 * Using a "num_spi_data_lanes" variable since ad3541/2 have
+		 * only DSPI interface, while ad355x is QSPI. Then using 2 as
+		 * DDR mode is considered always on (considering buffering
+		 * mode always).
 		 */
 		*val = DIV_ROUND_CLOSEST(st->data->bus_sample_data_clock_hz *
-					 4 * 2, chan->scan_type.realbits);
+					 st->model_data->num_spi_data_lanes * 2,
+					 chan->scan_type.realbits);
 
 		return IIO_VAL_INT;
 
 	case IIO_CHAN_INFO_RAW:
+		/* For RAW accesses, stay always in simple-spi. */
 		ret = st->data->bus_reg_read(st->back,
 				AD3552R_REG_ADDR_CH_DAC_16B(chan->channel),
 				val, 2);
@@ -93,6 +124,7 @@ static int ad3552r_hs_write_raw(struct iio_dev *indio_dev,
 
 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
+		/* For RAW accesses, stay always in simple-spi. */
 		iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {
 			return st->data->bus_reg_write(st->back,
 				    AD3552R_REG_ADDR_CH_DAC_16B(chan->channel),
@@ -104,6 +136,42 @@ static int ad3552r_hs_write_raw(struct iio_dev *indio_dev,
 	}
 }
 
+static int ad3552r_hs_set_bus_io_mode_hs(struct ad3552r_hs_state *st)
+{
+	int bus_mode;
+
+	if (st->model_data->num_spi_data_lanes == 4)
+		bus_mode = AD3552R_IO_MODE_QSPI;
+	else
+		bus_mode = AD3552R_IO_MODE_DSPI;
+
+	return st->data->bus_set_io_mode(st->back, bus_mode);
+}
+
+static int ad3552r_hs_set_target_io_mode_hs(struct ad3552r_hs_state *st)
+{
+	int mode_target;
+
+	/*
+	 * Best access for secondary reg area, QSPI where possible,
+	 * else as DSPI.
+	 */
+	if (st->model_data->num_spi_data_lanes == 4)
+		mode_target = AD3552R_QUAD_SPI;
+	else
+		mode_target = AD3552R_DUAL_SPI;
+
+	/*
+	 * Better to not use update here, since generally it is already
+	 * set as DDR mode, and it's not possible to read in DDR mode.
+	 */
+	return st->data->bus_reg_write(st->back,
+				AD3552R_REG_ADDR_TRANSFER_REGISTER,
+				FIELD_PREP(AD3552R_MASK_MULTI_IO_MODE,
+					   mode_target) |
+				AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE, 1);
+}
+
 static int ad3552r_hs_buffer_postenable(struct iio_dev *indio_dev)
 {
 	struct ad3552r_hs_state *st = iio_priv(indio_dev);
@@ -132,6 +200,11 @@ static int ad3552r_hs_buffer_postenable(struct iio_dev *indio_dev)
 		return -EINVAL;
 	}
 
+	/*
+	 * With ad3541/2r supoport, QSPI pin is held low at reset from HDL,
+	 * streaming start sequence must respect strictly the order below.
+	 */
+
 	/* Primary region access, set streaming mode (now in SPI + SDR). */
 	ret = ad3552r_qspi_update_reg_bits(st,
 					   AD3552R_REG_ADDR_INTERFACE_CONFIG_B,
@@ -139,48 +212,114 @@ static int ad3552r_hs_buffer_postenable(struct iio_dev *indio_dev)
 	if (ret)
 		return ret;
 
-	ret = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_STREAM_MODE,
+	/*
+	 * Set target loop len, 0x2c 0r 0x2a, descending loop,
+	 * and keeping loop len value so it's not cleared hereafter when
+	 * enabling streaming mode (cleared by CS_ up).
+	 */
+	ret = ad3552r_qspi_update_reg_bits(st,
+		AD3552R_REG_ADDR_TRANSFER_REGISTER,
+		AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE,
+		AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE, 1);
+	if (ret)
+		goto exit_err_streaming;
+
+	ret = st->data->bus_reg_write(st->back,
+				      AD3552R_REG_ADDR_STREAM_MODE,
 				      loop_len, 1);
 	if (ret)
-		return ret;
+		goto exit_err_streaming;
 
-	/* Inform DAC chip to switch into DDR mode */
-	ret = ad3552r_qspi_update_reg_bits(st,
-					   AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
-					   AD3552R_MASK_SPI_CONFIG_DDR,
-					   AD3552R_MASK_SPI_CONFIG_DDR, 1);
+	/*
+	 * Registers dump for debug purposes is only possible until here,
+	 * read in primary region must be SPI SDR (DDR read is never possible,
+	 * D/QSPI SDR read in primary region is also not possible).
+	 */
+
+	/* Setting DDR now, caching current config_d. */
+	ret = st->data->bus_reg_read(st->back,
+				     AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
+				     &st->config_d, 1);
 	if (ret)
-		return ret;
+		goto exit_err_streaming;
+
+	st->config_d |= AD3552R_MASK_SPI_CONFIG_DDR;
+	ret = st->data->bus_reg_write(st->back,
+				      AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
+				      st->config_d, 1);
+
+	if (ret)
+		goto exit_err_streaming;
 
-	/* Inform DAC IP to go for DDR mode from now on */
 	ret = iio_backend_ddr_enable(st->back);
-	if (ret) {
-		dev_err(st->dev, "could not set DDR mode, not streaming");
-		goto exit_err;
-	}
+	if (ret)
+		goto exit_err_ddr_mode_target;
 
+	/*
+	 * From here onward mode is DDR, so reading any register is not
+	 * possible anymore, including calling "ad3552r_qspi_update_reg_bits"
+	 * function.
+	 */
+
+	/* Set target to best high speed mode (D or QSPI). */
+	ret = ad3552r_hs_set_target_io_mode_hs(st);
+	if (ret)
+		goto exit_err_ddr_mode;
+
+	/* Set bus to best high speed mode (D or QSPI). */
+	ret = ad3552r_hs_set_bus_io_mode_hs(st);
+	if (ret)
+		goto exit_err_bus_mode_target;
+
+	/*
+	 * Backend setup must be done now only, or related register values
+	 * will be disrupted by previous bus accesses.
+	 */
 	ret = iio_backend_data_transfer_addr(st->back, val);
 	if (ret)
-		goto exit_err;
+		goto exit_err_bus_mode_target;
 
 	ret = iio_backend_data_format_set(st->back, 0, &fmt);
 	if (ret)
-		goto exit_err;
+		goto exit_err_bus_mode_target;
 
 	ret = iio_backend_data_stream_enable(st->back);
 	if (ret)
-		goto exit_err;
+		goto exit_err_bus_mode_target;
 
 	return 0;
 
-exit_err:
-	ad3552r_qspi_update_reg_bits(st,
-				     AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
-				     AD3552R_MASK_SPI_CONFIG_DDR,
-				     0, 1);
+exit_err_bus_mode_target:
+	/* Back to simple SPI, not using update to avoid read. */
+	st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_TRANSFER_REGISTER,
+				FIELD_PREP(AD3552R_MASK_MULTI_IO_MODE,
+					   AD3552R_SPI) |
+				AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE, 1);
 
+	/*
+	 * Back bus to simple SPI, this must be executed together with above
+	 * target mode unwind, and can be done only after it.
+	 */
+	st->data->bus_set_io_mode(st->back, AD3552R_IO_MODE_SPI);
+
+exit_err_ddr_mode:
 	iio_backend_ddr_disable(st->back);
 
+exit_err_ddr_mode_target:
+	/*
+	 * Back to SDR.
+	 * In DDR we cannot read, whatever the mode is, so not using update.
+	 */
+	st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
+				FIELD_PREP(AD3552R_MASK_SDO_DRIVE_STRENGTH, 1),
+				1);
+
+exit_err_streaming:
+	/* Back to single instruction mode, disabling loop. */
+	st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_INTERFACE_CONFIG_B,
+				AD3552R_MASK_SINGLE_INST |
+				AD3552R_MASK_SHORT_INSTRUCTION, 1);
+
 	return ret;
 }
 
@@ -193,11 +332,22 @@ static int ad3552r_hs_buffer_predisable(struct iio_dev *indio_dev)
 	if (ret)
 		return ret;
 
-	/* Inform DAC to set in SDR mode */
-	ret = ad3552r_qspi_update_reg_bits(st,
-					   AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
-					   AD3552R_MASK_SPI_CONFIG_DDR,
-					   0, 1);
+	/*
+	 * Set us to simple SPI, even if still in ddr, so to be able
+	 * to write in primary region.
+	 */
+	ret = st->data->bus_set_io_mode(st->back, AD3552R_IO_MODE_SPI);
+	if (ret)
+		return ret;
+
+	/*
+	 * Back to SDR
+	 * (in DDR we cannot read, whatever the mode is, so not using update).
+	 */
+	st->config_d &= ~AD3552R_MASK_SPI_CONFIG_DDR;
+	ret = st->data->bus_reg_write(st->back,
+				      AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
+				      st->config_d, 1);
 	if (ret)
 		return ret;
 
@@ -205,11 +355,21 @@ static int ad3552r_hs_buffer_predisable(struct iio_dev *indio_dev)
 	if (ret)
 		return ret;
 
-	/* Back to single instruction mode, disabling loop. */
+	/*
+	 * Back to simple SPI for secondary region too now,
+	 * so to be able to dump/read registers there too if needed.
+	 */
 	ret = ad3552r_qspi_update_reg_bits(st,
-					   AD3552R_REG_ADDR_INTERFACE_CONFIG_B,
-					   AD3552R_MASK_SINGLE_INST,
-					   AD3552R_MASK_SINGLE_INST, 1);
+					   AD3552R_REG_ADDR_TRANSFER_REGISTER,
+					   AD3552R_MASK_MULTI_IO_MODE,
+					   AD3552R_SPI, 1);
+	if (ret)
+		return ret;
+
+	/* Back to single instruction mode, disabling loop. */
+	ret = ad3552r_update_reg_bits(st, AD3552R_REG_ADDR_INTERFACE_CONFIG_B,
+				      AD3552R_MASK_SINGLE_INST,
+				      AD3552R_MASK_SINGLE_INST, 1);
 	if (ret)
 		return ret;
 
@@ -319,6 +479,7 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
 	if (ret)
 		return ret;
 
+	/* HDL starts with DDR enabled, disabling it. */
 	ret = iio_backend_ddr_disable(st->back);
 	if (ret)
 		return ret;
@@ -352,6 +513,8 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
 			 "Chip ID mismatch, detected 0x%x but expected 0x%x\n",
 			 id, st->model_data->chip_id);
 
+	dev_info(st->dev, "chip id %s detected", st->model_data->model_name);
+
 	/* Clear reset error flag, see ad3552r manual, rev B table 38. */
 	ret = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_ERR_STATUS,
 				      AD3552R_MASK_RESET_STATUS, 1);
@@ -364,14 +527,6 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
 	if (ret)
 		return ret;
 
-	ret = st->data->bus_reg_write(st->back,
-				AD3552R_REG_ADDR_TRANSFER_REGISTER,
-				FIELD_PREP(AD3552R_MASK_MULTI_IO_MODE,
-					   AD3552R_QUAD_SPI) |
-				AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE, 1);
-	if (ret)
-		return ret;
-
 	ret = iio_backend_data_source_set(st->back, 0, IIO_BACKEND_EXTERNAL);
 	if (ret)
 		return ret;
@@ -528,6 +683,9 @@ static int ad3552r_hs_probe(struct platform_device *pdev)
 }
 
 static const struct of_device_id ad3552r_hs_of_id[] = {
+	{ .compatible = "adi,ad3541r", .data = &ad3541r_model_data },
+	{ .compatible = "adi,ad3542r", .data = &ad3542r_model_data },
+	{ .compatible = "adi,ad3551r", .data = &ad3551r_model_data },
 	{ .compatible = "adi,ad3552r", .data = &ad3552r_model_data },
 	{ }
 };
diff --git a/drivers/iio/dac/ad3552r.h b/drivers/iio/dac/ad3552r.h
index 23f038464a0c..9d450019ece9 100644
--- a/drivers/iio/dac/ad3552r.h
+++ b/drivers/iio/dac/ad3552r.h
@@ -132,6 +132,8 @@
 
 #define AD3552R_MAX_RANGES	5
 #define AD3542R_MAX_RANGES	5
+#define AD3552R_SPI		0
+#define AD3552R_DUAL_SPI	1
 #define AD3552R_QUAD_SPI	2
 
 extern const s32 ad3552r_ch_ranges[AD3552R_MAX_RANGES][2];
@@ -156,6 +158,7 @@ struct ad3552r_model_data {
 	const s32 (*ranges_table)[2];
 	int num_ranges;
 	bool requires_output_range;
+	int num_spi_data_lanes;
 };
 
 struct ad3552r_ch_data {

-- 
2.47.0

[PATCH v2 9/9] iio: dac: ad3552r-hs: update function name (non functional)

[Angelo Dureghello]

From: Angelo Dureghello <adureghello@baylibre.com>

Update ad3552r_qspi_update_reg_bits function name to a more
generic name, since used mode can be SIMPLE/DUAL/QUAD SPI.

Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
---
 drivers/iio/dac/ad3552r-hs.c | 58 ++++++++++++++++++++------------------------
 1 file changed, 26 insertions(+), 32 deletions(-)

diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c
index 5995bab6a9b1..53ab912eea11 100644
--- a/drivers/iio/dac/ad3552r-hs.c
+++ b/drivers/iio/dac/ad3552r-hs.c
@@ -56,9 +56,9 @@ struct ad3552r_hs_state {
 	u32 config_d;
 };
 
-static int ad3552r_qspi_update_reg_bits(struct ad3552r_hs_state *st,
-					u32 reg, u32 mask, u32 val,
-					size_t xfer_size)
+static int ad3552r_update_reg_bits(struct ad3552r_hs_state *st,
+				   u32 reg, u32 mask, u32 val,
+				   size_t xfer_size)
 {
 	u32 rval;
 	int ret;
@@ -206,9 +206,8 @@ static int ad3552r_hs_buffer_postenable(struct iio_dev *indio_dev)
 	 */
 
 	/* Primary region access, set streaming mode (now in SPI + SDR). */
-	ret = ad3552r_qspi_update_reg_bits(st,
-					   AD3552R_REG_ADDR_INTERFACE_CONFIG_B,
-					   AD3552R_MASK_SINGLE_INST, 0, 1);
+	ret = ad3552r_update_reg_bits(st, AD3552R_REG_ADDR_INTERFACE_CONFIG_B,
+				      AD3552R_MASK_SINGLE_INST, 0, 1);
 	if (ret)
 		return ret;
 
@@ -217,10 +216,9 @@ static int ad3552r_hs_buffer_postenable(struct iio_dev *indio_dev)
 	 * and keeping loop len value so it's not cleared hereafter when
 	 * enabling streaming mode (cleared by CS_ up).
 	 */
-	ret = ad3552r_qspi_update_reg_bits(st,
-		AD3552R_REG_ADDR_TRANSFER_REGISTER,
-		AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE,
-		AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE, 1);
+	ret = ad3552r_update_reg_bits(st, AD3552R_REG_ADDR_TRANSFER_REGISTER,
+				      AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE,
+				      AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE, 1);
 	if (ret)
 		goto exit_err_streaming;
 
@@ -247,7 +245,6 @@ static int ad3552r_hs_buffer_postenable(struct iio_dev *indio_dev)
 	ret = st->data->bus_reg_write(st->back,
 				      AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
 				      st->config_d, 1);
-
 	if (ret)
 		goto exit_err_streaming;
 
@@ -257,7 +254,7 @@ static int ad3552r_hs_buffer_postenable(struct iio_dev *indio_dev)
 
 	/*
 	 * From here onward mode is DDR, so reading any register is not
-	 * possible anymore, including calling "ad3552r_qspi_update_reg_bits"
+	 * possible anymore, including calling "ad3552r_update_reg_bits"
 	 * function.
 	 */
 
@@ -359,10 +356,9 @@ static int ad3552r_hs_buffer_predisable(struct iio_dev *indio_dev)
 	 * Back to simple SPI for secondary region too now,
 	 * so to be able to dump/read registers there too if needed.
 	 */
-	ret = ad3552r_qspi_update_reg_bits(st,
-					   AD3552R_REG_ADDR_TRANSFER_REGISTER,
-					   AD3552R_MASK_MULTI_IO_MODE,
-					   AD3552R_SPI, 1);
+	ret = ad3552r_update_reg_bits(st, AD3552R_REG_ADDR_TRANSFER_REGISTER,
+				      AD3552R_MASK_MULTI_IO_MODE,
+				      AD3552R_SPI, 1);
 	if (ret)
 		return ret;
 
@@ -386,10 +382,10 @@ static inline int ad3552r_hs_set_output_range(struct ad3552r_hs_state *st,
 	else
 		val = FIELD_PREP(AD3552R_MASK_CH1_RANGE, mode);
 
-	return ad3552r_qspi_update_reg_bits(st,
-					AD3552R_REG_ADDR_CH0_CH1_OUTPUT_RANGE,
-					AD3552R_MASK_CH_OUTPUT_RANGE_SEL(ch),
-					val, 1);
+	return ad3552r_update_reg_bits(st,
+				       AD3552R_REG_ADDR_CH0_CH1_OUTPUT_RANGE,
+				       AD3552R_MASK_CH_OUTPUT_RANGE_SEL(ch),
+				       val, 1);
 }
 
 static int ad3552r_hs_reset(struct ad3552r_hs_state *st)
@@ -405,10 +401,10 @@ static int ad3552r_hs_reset(struct ad3552r_hs_state *st)
 		fsleep(10);
 		gpiod_set_value_cansleep(st->reset_gpio, 0);
 	} else {
-		ret = ad3552r_qspi_update_reg_bits(st,
-					AD3552R_REG_ADDR_INTERFACE_CONFIG_A,
-					AD3552R_MASK_SOFTWARE_RESET,
-					AD3552R_MASK_SOFTWARE_RESET, 1);
+		ret = ad3552r_update_reg_bits(st,
+			AD3552R_REG_ADDR_INTERFACE_CONFIG_A,
+			AD3552R_MASK_SOFTWARE_RESET,
+			AD3552R_MASK_SOFTWARE_RESET, 1);
 		if (ret)
 			return ret;
 	}
@@ -541,19 +537,17 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
 
 	val = ret;
 
-	ret = ad3552r_qspi_update_reg_bits(st,
-				AD3552R_REG_ADDR_SH_REFERENCE_CONFIG,
-				AD3552R_MASK_REFERENCE_VOLTAGE_SEL,
-				val, 1);
+	ret = ad3552r_update_reg_bits(st, AD3552R_REG_ADDR_SH_REFERENCE_CONFIG,
+				      AD3552R_MASK_REFERENCE_VOLTAGE_SEL,
+				      val, 1);
 	if (ret)
 		return ret;
 
 	ret = ad3552r_get_drive_strength(st->dev, &val);
 	if (!ret) {
-		ret = ad3552r_qspi_update_reg_bits(st,
-					AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
-					AD3552R_MASK_SDO_DRIVE_STRENGTH,
-					val, 1);
+		ret = ad3552r_update_reg_bits(st,
+			AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
+			AD3552R_MASK_SDO_DRIVE_STRENGTH, val, 1);
 		if (ret)
 			return ret;
 	}

-- 
2.47.0

Re: [PATCH v2 1/9] iio: dac: ad3552r-common: fix ad3541/2r ranges

[David Lechner]

On 1/8/25 11:29 AM, Angelo Dureghello wrote:
> From: Angelo Dureghello <adureghello@baylibre.com>
> 
> Fix ad3541/2r voltage ranges to be as per ad3542r datasheet,
> rev. C, table 38 (page 57).
> 
> The wrong ad354xr ranges was generating erroneous Vpp output.
> 
> In more details:
> - fix wrong number of ranges, they are 5 ranges, not 6,
> - remove non-existent 0-3V range,
> - adjust order, since ad3552r_find_range() get a wrong index,
>   producing a wrong Vpp as output.
> 
> Retested all the ranges on real hardware, EVALAD3542RFMCZ:
> 
> adi,output-range-microvolt (fdt):
> <(000000) (2500000)>;   ok (Rfbx1, switch 10)
> <(000000) (5000000)>;   ok (Rfbx1, switch 10)
> <(000000) (10000000)>;  ok (Rfbx1, switch 10)
> <(-5000000) (5000000)>; ok (Rfbx2, switch +/- 5)
> <(-2500000) (7500000)>; ok (Rfbx2, switch -2.5/7.5)
> 
> Fixes: 8f2b54824b28 ("drivers:iio:dac: Add AD3552R driver support")
> Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
> ---
Reviewed-by: David Lechner <dlechner@baylibre.com>

Re: [PATCH v2 2/9] iio: dac: ad3552r-hs: clear reset status flag

[David Lechner]

On 1/8/25 11:29 AM, Angelo Dureghello wrote:
> From: Angelo Dureghello <adureghello@baylibre.com>
> 
> Clear reset status flag, to keep error status register
> clean after reset (ad3552r manual, rev B table 38).
> 
> Reset error flag was left to 1, so debugging registers, the
> "Error Status Register" was dirty (0x01). It is important
> to clear this bit, so if there is any reset event over normal
> working mode, it is possible to detect it.

Do we need to do the same for ad3552r.c as well? Separate patch of course.

> 
> Fixes: 0b4d9fe58be8 ("iio: dac: ad3552r: add high-speed platform driver")
> Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
> ---
Reviewed-by: David Lechner <dlechner@baylibre.com>

Re: [PATCH v2 3/9] iio: dac: adi-axi-dac: modify stream enable

[David Lechner]

On 1/8/25 11:29 AM, Angelo Dureghello wrote:
> From: Angelo Dureghello <adureghello@baylibre.com>
> 
> Change suggested from the AXI HDL team, modify the function
> axi_dac_data_stream_enable() to check for interface busy, to avoid
> possible issues when starting the stream.
> 
> Fixes: e61d7178429a ("iio: dac: adi-axi-dac: extend features")
> Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
> ---
>  drivers/iio/dac/adi-axi-dac.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/drivers/iio/dac/adi-axi-dac.c b/drivers/iio/dac/adi-axi-dac.c
> index b143f7ed6847..d02eb535b648 100644
> --- a/drivers/iio/dac/adi-axi-dac.c
> +++ b/drivers/iio/dac/adi-axi-dac.c
> @@ -585,6 +585,17 @@ static int axi_dac_ddr_disable(struct iio_backend *back)
>  static int axi_dac_data_stream_enable(struct iio_backend *back)
>  {
>  	struct axi_dac_state *st = iio_backend_get_priv(back);
> +	int ret, val;
> +
> +	ret = regmap_read_poll_timeout(st->regmap,
> +				AXI_DAC_UI_STATUS_REG, val,
> +				FIELD_GET(AXI_DAC_UI_STATUS_IF_BUSY, val) == 0,
> +				10, 100 * KILO);
> +	if (ret) {
> +		if (ret == -ETIMEDOUT)
> +			dev_err(st->dev, "AXI read timeout\n");

Do we really need the `dev_err()`? I think the ETIMEDOUT will bubble up to
userspace anyway via buffer_postenable.

If we keep it though, it could use a better message. The important part is that
the AXI IP block never became ready, not that reading the register timed out.

> +		return ret;
> +	}
>  
>  	return regmap_set_bits(st->regmap, AXI_DAC_CUSTOM_CTRL_REG,
>  			       AXI_DAC_CUSTOM_CTRL_STREAM_ENABLE);
> 

Re: [PATCH v2 4/9] iio: dac: adi-axi-dac: add bus mode setup

[David Lechner]

On 1/8/25 11:29 AM, Angelo Dureghello wrote:
> From: Angelo Dureghello <adureghello@baylibre.com>
> 
> The ad354xr requires DSPI mode (2 data lanes) to work in buffering
> mode, so backend needs to allow a mode selection between:
>     SPI  (entire ad35xxr family),
>     DSPI (ad354xr),
>     QSPI (ad355xr).
> 

It wouldn't hurt to mention here why AXI_DAC_CUSTOM_CTRL_SYNCED_TRANSFER is
removed. It looks like it was just added by mistake in the original code and
isn't used anywhere.

> Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
> ---
>  drivers/iio/dac/ad3552r-hs.h  |  8 ++++++++
>  drivers/iio/dac/adi-axi-dac.c | 26 +++++++++++++++++++++++++-
>  2 files changed, 33 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/dac/ad3552r-hs.h b/drivers/iio/dac/ad3552r-hs.h
> index 724261d38dea..4a9e35234124 100644
> --- a/drivers/iio/dac/ad3552r-hs.h
> +++ b/drivers/iio/dac/ad3552r-hs.h
> @@ -8,11 +8,19 @@
>  
>  struct iio_backend;
>  
> +enum ad3552r_io_mode {
> +	AD3552R_IO_MODE_SPI,
> +	AD3552R_IO_MODE_DSPI,
> +	AD3552R_IO_MODE_QSPI,
> +};
> +
>  struct ad3552r_hs_platform_data {
>  	int (*bus_reg_read)(struct iio_backend *back, u32 reg, u32 *val,
>  			    size_t data_size);
>  	int (*bus_reg_write)(struct iio_backend *back, u32 reg, u32 val,
>  			     size_t data_size);
> +	int (*bus_set_io_mode)(struct iio_backend *back,
> +			       enum ad3552r_io_mode mode);
>  	u32 bus_sample_data_clock_hz;
>  };
>  
> diff --git a/drivers/iio/dac/adi-axi-dac.c b/drivers/iio/dac/adi-axi-dac.c
> index d02eb535b648..79ca158c1ad9 100644
> --- a/drivers/iio/dac/adi-axi-dac.c
> +++ b/drivers/iio/dac/adi-axi-dac.c
> @@ -64,7 +64,7 @@
>  #define   AXI_DAC_UI_STATUS_IF_BUSY		BIT(4)
>  #define AXI_DAC_CUSTOM_CTRL_REG			0x008C
>  #define   AXI_DAC_CUSTOM_CTRL_ADDRESS		GENMASK(31, 24)
> -#define   AXI_DAC_CUSTOM_CTRL_SYNCED_TRANSFER	BIT(2)
> +#define   AXI_DAC_CUSTOM_CTRL_MULTI_IO_MODE	GENMASK(3, 2)
>  #define   AXI_DAC_CUSTOM_CTRL_STREAM		BIT(1)
>  #define   AXI_DAC_CUSTOM_CTRL_TRANSFER_DATA	BIT(0)
>  
> @@ -725,6 +725,29 @@ static int axi_dac_bus_reg_read(struct iio_backend *back, u32 reg, u32 *val,
>  	return regmap_read(st->regmap, AXI_DAC_CUSTOM_RD_REG, val);
>  }
>  
> +static int axi_dac_bus_set_io_mode(struct iio_backend *back,
> +				   enum ad3552r_io_mode mode)
> +{
> +	struct axi_dac_state *st = iio_backend_get_priv(back);
> +	int ival, ret;

Don't we need to protect against concurrent register access?

	guard(mutex)(&st->lock);

> +
> +	ret = regmap_update_bits(st->regmap, AXI_DAC_CUSTOM_CTRL_REG,
> +				 AXI_DAC_CUSTOM_CTRL_MULTI_IO_MODE,
> +				 FIELD_PREP(AXI_DAC_CUSTOM_CTRL_MULTI_IO_MODE, mode));
> +	if (ret)
> +		return ret;
> +
> +	ret = regmap_read_poll_timeout(st->regmap,
> +				       AXI_DAC_UI_STATUS_REG, ival,
> +				       FIELD_GET(AXI_DAC_UI_STATUS_IF_BUSY, ival) == 0,
> +				       10, 100 * KILO);
> +
> +	if (ret == -ETIMEDOUT)
> +		dev_err(st->dev, "AXI read timeout\n");

Same comment here as previous patch, is `dev_err()` really that helpful?

> +
> +	return ret;
> +}
> +
>  static void axi_dac_child_remove(void *data)
>  {
>  	platform_device_unregister(data);
> @@ -736,6 +759,7 @@ static int axi_dac_create_platform_device(struct axi_dac_state *st,
>  	struct ad3552r_hs_platform_data pdata = {
>  		.bus_reg_read = axi_dac_bus_reg_read,
>  		.bus_reg_write = axi_dac_bus_reg_write,
> +		.bus_set_io_mode = axi_dac_bus_set_io_mode,
>  		.bus_sample_data_clock_hz = st->dac_clk_rate,
>  	};
>  	struct platform_device_info pi = {
> 

Re: [PATCH v2 6/9] iio: dac: ad3552r-hs: use instruction mode for configuration

[David Lechner]

On 1/8/25 11:29 AM, Angelo Dureghello wrote:
> From: Angelo Dureghello <adureghello@baylibre.com>
> 
> Use "instruction" mode over initial configuration and all other
> non-streaming operations.
> 
> DAC boots in streaming mode as default, and the driver is not
> changing this mode.
> 
> Instruction r/w is still working becouse instruction is processed

s/becouse/because/

> from the DAC after chip select is deasserted, this works until
> loop mode is 0 or greater than the instruction size.
> 
> All initial operations should be more safely done in instruction
> mode, a mode provided for this.

I'm not sure it is really "safer". The way I read the datasheet, this just
enables bulk reads of multiple registers. So unless we need to do bulk reads
it seems like this is just adding extra complexity to the driver without a
tangible benefit.

> 
> Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
> ---
>  drivers/iio/dac/ad3552r-hs.c | 22 ++++++++++++++++++++++
>  1 file changed, 22 insertions(+)
> 
> diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c
> index 27949f207d42..991b11702273 100644
> --- a/drivers/iio/dac/ad3552r-hs.c
> +++ b/drivers/iio/dac/ad3552r-hs.c
> @@ -132,6 +132,13 @@ static int ad3552r_hs_buffer_postenable(struct iio_dev *indio_dev)
>  		return -EINVAL;
>  	}
>  
> +	/* Primary region access, set streaming mode (now in SPI + SDR). */
> +	ret = ad3552r_qspi_update_reg_bits(st,
> +					   AD3552R_REG_ADDR_INTERFACE_CONFIG_B,
> +					   AD3552R_MASK_SINGLE_INST, 0, 1);

Missing undoing this operation in the error path if a later operation in this
function fails?

> +	if (ret)
> +		return ret;
> +
>  	ret = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_STREAM_MODE,
>  				      loop_len, 1);
>  	if (ret)

Re: [PATCH v2 7/9] iio: dac: ad3552r: share model data structures

[David Lechner]

On 1/8/25 11:29 AM, Angelo Dureghello wrote:
> From: Angelo Dureghello <adureghello@baylibre.com>
> 
> Preparing for new parts to be added also in the hs driver,
> set model data structures in ad3552r-common.c, to be accessible
> from both -hs and non hs driver.
> 
> Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
> ---
>  drivers/iio/dac/ad3552r-common.c | 40 ++++++++++++++++++++++++++++++++++++++++
>  drivers/iio/dac/ad3552r-hs.c     |  8 --------
>  drivers/iio/dac/ad3552r.c        | 36 ------------------------------------
>  drivers/iio/dac/ad3552r.h        |  5 +++++
>  4 files changed, 45 insertions(+), 44 deletions(-)
> 
> diff --git a/drivers/iio/dac/ad3552r-common.c b/drivers/iio/dac/ad3552r-common.c
> index 03e0864f5084..36920ec95836 100644
> --- a/drivers/iio/dac/ad3552r-common.c
> +++ b/drivers/iio/dac/ad3552r-common.c
> @@ -37,6 +37,46 @@ static const s32 gains_scaling_table[] = {
>  	[AD3552R_CH_GAIN_SCALING_0_125]		= 125
>  };
>  
> +const struct ad3552r_model_data ad3541r_model_data = {
> +	.model_name = "ad3541r",
> +	.chip_id = AD3541R_ID,
> +	.num_hw_channels = 1,
> +	.ranges_table = ad3542r_ch_ranges,
> +	.num_ranges = ARRAY_SIZE(ad3542r_ch_ranges),
> +	.requires_output_range = true,
> +};
> +EXPORT_SYMBOL_NS_GPL(ad3541r_model_data, "IIO_AD3552R");
> +
> +const struct ad3552r_model_data ad3542r_model_data = {
> +	.model_name = "ad3542r",
> +	.chip_id = AD3542R_ID,
> +	.num_hw_channels = 2,
> +	.ranges_table = ad3542r_ch_ranges,
> +	.num_ranges = ARRAY_SIZE(ad3542r_ch_ranges),
> +	.requires_output_range = true,
> +};
> +EXPORT_SYMBOL_NS_GPL(ad3542r_model_data, "IIO_AD3552R");
> +
> +const struct ad3552r_model_data ad3551r_model_data = {
> +	.model_name = "ad3551r",
> +	.chip_id = AD3551R_ID,
> +	.num_hw_channels = 1,
> +	.ranges_table = ad3552r_ch_ranges,
> +	.num_ranges = ARRAY_SIZE(ad3552r_ch_ranges),
> +	.requires_output_range = false,
> +};
> +EXPORT_SYMBOL_NS_GPL(ad3551r_model_data, "IIO_AD3552R");
> +
> +const struct ad3552r_model_data ad3552r_model_data = {
> +	.model_name = "ad3552r",
> +	.chip_id = AD3552R_ID,
> +	.num_hw_channels = 2,
> +	.ranges_table = ad3552r_ch_ranges,
> +	.num_ranges = ARRAY_SIZE(ad3552r_ch_ranges),
> +	.requires_output_range = false,
> +};
> +EXPORT_SYMBOL_NS_GPL(ad3552r_model_data, "IIO_AD3552R");
> +
>  u16 ad3552r_calc_custom_gain(u8 p, u8 n, s16 goffs)
>  {
>  	return FIELD_PREP(AD3552R_MASK_CH_RANGE_OVERRIDE, 1) |
> diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c
> index 991b11702273..bfb6228c9b9b 100644
> --- a/drivers/iio/dac/ad3552r-hs.c
> +++ b/drivers/iio/dac/ad3552r-hs.c
> @@ -527,14 +527,6 @@ static int ad3552r_hs_probe(struct platform_device *pdev)
>  	return devm_iio_device_register(&pdev->dev, indio_dev);
>  }
>  
> -static const struct ad3552r_model_data ad3552r_model_data = {
> -	.model_name = "ad3552r",
> -	.chip_id = AD3552R_ID,
> -	.num_hw_channels = 2,
> -	.ranges_table = ad3552r_ch_ranges,
> -	.num_ranges = ARRAY_SIZE(ad3552r_ch_ranges),
> -};
> -
>  static const struct of_device_id ad3552r_hs_of_id[] = {
>  	{ .compatible = "adi,ad3552r", .data = &ad3552r_model_data },
>  	{ }
> diff --git a/drivers/iio/dac/ad3552r.c b/drivers/iio/dac/ad3552r.c
> index e7206af53af6..9d28e06b80c0 100644
> --- a/drivers/iio/dac/ad3552r.c
> +++ b/drivers/iio/dac/ad3552r.c
> @@ -649,42 +649,6 @@ static int ad3552r_probe(struct spi_device *spi)
>  	return devm_iio_device_register(&spi->dev, indio_dev);
>  }
>  
> -static const struct ad3552r_model_data ad3541r_model_data = {
> -	.model_name = "ad3541r",
> -	.chip_id = AD3541R_ID,
> -	.num_hw_channels = 1,
> -	.ranges_table = ad3542r_ch_ranges,
> -	.num_ranges = ARRAY_SIZE(ad3542r_ch_ranges),
> -	.requires_output_range = true,
> -};
> -
> -static const struct ad3552r_model_data ad3542r_model_data = {
> -	.model_name = "ad3542r",
> -	.chip_id = AD3542R_ID,
> -	.num_hw_channels = 2,
> -	.ranges_table = ad3542r_ch_ranges,
> -	.num_ranges = ARRAY_SIZE(ad3542r_ch_ranges),
> -	.requires_output_range = true,
> -};
> -
> -static const struct ad3552r_model_data ad3551r_model_data = {
> -	.model_name = "ad3551r",
> -	.chip_id = AD3551R_ID,
> -	.num_hw_channels = 1,
> -	.ranges_table = ad3552r_ch_ranges,
> -	.num_ranges = ARRAY_SIZE(ad3552r_ch_ranges),
> -	.requires_output_range = false,
> -};
> -
> -static const struct ad3552r_model_data ad3552r_model_data = {
> -	.model_name = "ad3552r",
> -	.chip_id = AD3552R_ID,
> -	.num_hw_channels = 2,
> -	.ranges_table = ad3552r_ch_ranges,
> -	.num_ranges = ARRAY_SIZE(ad3552r_ch_ranges),
> -	.requires_output_range = false,
> -};
> -
>  static const struct spi_device_id ad3552r_id[] = {
>  	{
>  		.name = "ad3541r",
> diff --git a/drivers/iio/dac/ad3552r.h b/drivers/iio/dac/ad3552r.h
> index 4b5581039ae9..23f038464a0c 100644
> --- a/drivers/iio/dac/ad3552r.h
> +++ b/drivers/iio/dac/ad3552r.h
> @@ -137,6 +137,11 @@
>  extern const s32 ad3552r_ch_ranges[AD3552R_MAX_RANGES][2];
>  extern const s32 ad3542r_ch_ranges[AD3542R_MAX_RANGES][2];

Do the ranges still need to be extern now or can we make them static in
ad3552r-common.c?

>  
> +extern const struct ad3552r_model_data ad3541r_model_data;
> +extern const struct ad3552r_model_data ad3542r_model_data;
> +extern const struct ad3552r_model_data ad3551r_model_data;
> +extern const struct ad3552r_model_data ad3552r_model_data;
> +
>  enum ad3552r_id {
>  	AD3541R_ID = 0x400b,
>  	AD3542R_ID = 0x4009,
> 

Re: [PATCH v2 8/9] iio: dac: ad3552r-hs: add ad3541/2r support

[David Lechner]

On 1/8/25 11:29 AM, Angelo Dureghello wrote:
> From: Angelo Dureghello <adureghello@baylibre.com>
> 
> A new fpga HDL has been developed from ADI to support ad354xr

s/fpga/FPGA/

> devices.
> 
> Add support for ad3541r and ad3542r with following additions:
> 
> - use common device_info structures for hs and non hs drivers,
> - DMA buffering, use DSPI mode for ad354xr and QSPI for ad355xr,
> - change samplerate to respect number of lanes.

s/samplerate/sample rate/

> 
> Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
> ---
>  drivers/iio/dac/ad3552r-common.c |   4 +
>  drivers/iio/dac/ad3552r-hs.c     | 240 ++++++++++++++++++++++++++++++++-------
>  drivers/iio/dac/ad3552r.h        |   3 +
>  3 files changed, 206 insertions(+), 41 deletions(-)
> 
> diff --git a/drivers/iio/dac/ad3552r-common.c b/drivers/iio/dac/ad3552r-common.c
> index 36920ec95836..fa3050dc2efa 100644
> --- a/drivers/iio/dac/ad3552r-common.c
> +++ b/drivers/iio/dac/ad3552r-common.c
> @@ -44,6 +44,7 @@ const struct ad3552r_model_data ad3541r_model_data = {
>  	.ranges_table = ad3542r_ch_ranges,
>  	.num_ranges = ARRAY_SIZE(ad3542r_ch_ranges),
>  	.requires_output_range = true,
> +	.num_spi_data_lanes = 2,
>  };
>  EXPORT_SYMBOL_NS_GPL(ad3541r_model_data, "IIO_AD3552R");
>  
> @@ -54,6 +55,7 @@ const struct ad3552r_model_data ad3542r_model_data = {
>  	.ranges_table = ad3542r_ch_ranges,
>  	.num_ranges = ARRAY_SIZE(ad3542r_ch_ranges),
>  	.requires_output_range = true,
> +	.num_spi_data_lanes = 2,
>  };
>  EXPORT_SYMBOL_NS_GPL(ad3542r_model_data, "IIO_AD3552R");
>  
> @@ -64,6 +66,7 @@ const struct ad3552r_model_data ad3551r_model_data = {
>  	.ranges_table = ad3552r_ch_ranges,
>  	.num_ranges = ARRAY_SIZE(ad3552r_ch_ranges),
>  	.requires_output_range = false,
> +	.num_spi_data_lanes = 4,
>  };
>  EXPORT_SYMBOL_NS_GPL(ad3551r_model_data, "IIO_AD3552R");
>  
> @@ -74,6 +77,7 @@ const struct ad3552r_model_data ad3552r_model_data = {
>  	.ranges_table = ad3552r_ch_ranges,
>  	.num_ranges = ARRAY_SIZE(ad3552r_ch_ranges),
>  	.requires_output_range = false,
> +	.num_spi_data_lanes = 4,
>  };
>  EXPORT_SYMBOL_NS_GPL(ad3552r_model_data, "IIO_AD3552R");
>  
> diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c
> index bfb6228c9b9b..5995bab6a9b1 100644
> --- a/drivers/iio/dac/ad3552r-hs.c
> +++ b/drivers/iio/dac/ad3552r-hs.c
> @@ -19,6 +19,31 @@
>  #include "ad3552r.h"
>  #include "ad3552r-hs.h"
>  
> +/*
> + * Important notes for register map access:
> + * ========================================
> + *
> + * Register address space is divided in 2 regions, primary (config) and
> + * secondary (DAC). Primary region can only be accessed in simple SPI mode,
> + * with exception for ad355x models where setting QSPI pin high allows QSPI
> + * access to both the regions.
> + *
> + * Due to the fact that ad3541/2r do not implement QSPI, for proper device
> + * detection, HDL keeps "QSPI" pin level low at boot (see ad3552r manual, rev B
> + * table 7, pin 31, digital input). For this reason, actually the working mode
> + * between SPI, DSPI and QSPI must be set via software, configuring the target
> + * DAC appropriately, together with the backend api to configure the bus mode

s/api/API/

> + * accordingly.
> + *
> + * Also, important to note that none of the three modes allow to read in DDR.
> + *
> + * In non-buffering operations, mode is set to simple SPI SDR for all primary
> + * and secondary region r/w accesses, to avoid to switch the mode each time DAC
> + * register is accessed (raw accesses, r/w), and to be able to dump registers
> + * content (possible as non DDR only).
> + * In buffering mode, driver sets best possible mode, D/QSPI and DDR.
> + */
> +
>  struct ad3552r_hs_state {
>  	const struct ad3552r_model_data *model_data;
>  	struct gpio_desc *reset_gpio;
> @@ -27,6 +52,8 @@ struct ad3552r_hs_state {
>  	bool single_channel;
>  	struct ad3552r_ch_data ch_data[AD3552R_MAX_CH];
>  	struct ad3552r_hs_platform_data *data;
> +	/* INTERFACE_CONFIG_D register cache, in DDR we cannot read values. */
> +	u32 config_d;
>  };
>  
>  static int ad3552r_qspi_update_reg_bits(struct ad3552r_hs_state *st,
> @@ -56,15 +83,19 @@ static int ad3552r_hs_read_raw(struct iio_dev *indio_dev,
>  	switch (mask) {
>  	case IIO_CHAN_INFO_SAMP_FREQ:
>  		/*
> -		 * Using 4 lanes (QSPI), then using 2 as DDR mode is
> -		 * considered always on (considering buffering mode always).
> +		 * Using a "num_spi_data_lanes" variable since ad3541/2 have
> +		 * only DSPI interface, while ad355x is QSPI. Then using 2 as
> +		 * DDR mode is considered always on (considering buffering
> +		 * mode always).
>  		 */
>  		*val = DIV_ROUND_CLOSEST(st->data->bus_sample_data_clock_hz *
> -					 4 * 2, chan->scan_type.realbits);
> +					 st->model_data->num_spi_data_lanes * 2,
> +					 chan->scan_type.realbits);
>  
>  		return IIO_VAL_INT;
>  
>  	case IIO_CHAN_INFO_RAW:
> +		/* For RAW accesses, stay always in simple-spi. */
>  		ret = st->data->bus_reg_read(st->back,
>  				AD3552R_REG_ADDR_CH_DAC_16B(chan->channel),
>  				val, 2);
> @@ -93,6 +124,7 @@ static int ad3552r_hs_write_raw(struct iio_dev *indio_dev,
>  
>  	switch (mask) {
>  	case IIO_CHAN_INFO_RAW:
> +		/* For RAW accesses, stay always in simple-spi. */
>  		iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {
>  			return st->data->bus_reg_write(st->back,
>  				    AD3552R_REG_ADDR_CH_DAC_16B(chan->channel),
> @@ -104,6 +136,42 @@ static int ad3552r_hs_write_raw(struct iio_dev *indio_dev,
>  	}
>  }
>  
> +static int ad3552r_hs_set_bus_io_mode_hs(struct ad3552r_hs_state *st)
> +{
> +	int bus_mode;
> +
> +	if (st->model_data->num_spi_data_lanes == 4)
> +		bus_mode = AD3552R_IO_MODE_QSPI;
> +	else
> +		bus_mode = AD3552R_IO_MODE_DSPI;
> +
> +	return st->data->bus_set_io_mode(st->back, bus_mode);
> +}
> +
> +static int ad3552r_hs_set_target_io_mode_hs(struct ad3552r_hs_state *st)
> +{
> +	int mode_target;
> +
> +	/*
> +	 * Best access for secondary reg area, QSPI where possible,
> +	 * else as DSPI.
> +	 */
> +	if (st->model_data->num_spi_data_lanes == 4)
> +		mode_target = AD3552R_QUAD_SPI;
> +	else
> +		mode_target = AD3552R_DUAL_SPI;
> +
> +	/*
> +	 * Better to not use update here, since generally it is already
> +	 * set as DDR mode, and it's not possible to read in DDR mode.
> +	 */
> +	return st->data->bus_reg_write(st->back,
> +				AD3552R_REG_ADDR_TRANSFER_REGISTER,
> +				FIELD_PREP(AD3552R_MASK_MULTI_IO_MODE,
> +					   mode_target) |
> +				AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE, 1);
> +}
> +
>  static int ad3552r_hs_buffer_postenable(struct iio_dev *indio_dev)
>  {
>  	struct ad3552r_hs_state *st = iio_priv(indio_dev);
> @@ -132,6 +200,11 @@ static int ad3552r_hs_buffer_postenable(struct iio_dev *indio_dev)
>  		return -EINVAL;
>  	}
>  
> +	/*
> +	 * With ad3541/2r supoport, QSPI pin is held low at reset from HDL,

s/supoport/support/

> +	 * streaming start sequence must respect strictly the order below.
> +	 */
> +
>  	/* Primary region access, set streaming mode (now in SPI + SDR). */
>  	ret = ad3552r_qspi_update_reg_bits(st,
>  					   AD3552R_REG_ADDR_INTERFACE_CONFIG_B,
> @@ -139,48 +212,114 @@ static int ad3552r_hs_buffer_postenable(struct iio_dev *indio_dev)
>  	if (ret)
>  		return ret;
>  
> -	ret = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_STREAM_MODE,
> +	/*
> +	 * Set target loop len, 0x2c 0r 0x2a, descending loop,
> +	 * and keeping loop len value so it's not cleared hereafter when
> +	 * enabling streaming mode (cleared by CS_ up).

rewrap to be closer to 80 chars/line

> +	 */
> +	ret = ad3552r_qspi_update_reg_bits(st,
> +		AD3552R_REG_ADDR_TRANSFER_REGISTER,
> +		AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE,
> +		AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE, 1);
> +	if (ret)
> +		goto exit_err_streaming;
> +
> +	ret = st->data->bus_reg_write(st->back,
> +				      AD3552R_REG_ADDR_STREAM_MODE,
>  				      loop_len, 1);
>  	if (ret)
> -		return ret;
> +		goto exit_err_streaming;
>  
> -	/* Inform DAC chip to switch into DDR mode */
> -	ret = ad3552r_qspi_update_reg_bits(st,
> -					   AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
> -					   AD3552R_MASK_SPI_CONFIG_DDR,
> -					   AD3552R_MASK_SPI_CONFIG_DDR, 1);
> +	/*
> +	 * Registers dump for debug purposes is only possible until here,
> +	 * read in primary region must be SPI SDR (DDR read is never possible,
> +	 * D/QSPI SDR read in primary region is also not possible).
> +	 */

It doesn't look like we have debugfs implemented in this driver, so this
comment doesn't seem relent. And if we did, we could guard it with
iio_device_claim_direct_mode() to avoid the issue, so we shouldn't need
this comment in any case.

> +
> +	/* Setting DDR now, caching current config_d. */
> +	ret = st->data->bus_reg_read(st->back,
> +				     AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
> +				     &st->config_d, 1);
>  	if (ret)
> -		return ret;
> +		goto exit_err_streaming;
> +
> +	st->config_d |= AD3552R_MASK_SPI_CONFIG_DDR;
> +	ret = st->data->bus_reg_write(st->back,
> +				      AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
> +				      st->config_d, 1);
> +
> +	if (ret)
> +		goto exit_err_streaming;
>  
> -	/* Inform DAC IP to go for DDR mode from now on */
>  	ret = iio_backend_ddr_enable(st->back);
> -	if (ret) {
> -		dev_err(st->dev, "could not set DDR mode, not streaming");
> -		goto exit_err;
> -	}
> +	if (ret)
> +		goto exit_err_ddr_mode_target;
>  
> +	/*
> +	 * From here onward mode is DDR, so reading any register is not
> +	 * possible anymore, including calling "ad3552r_qspi_update_reg_bits"
> +	 * function.
> +	 */
> +
> +	/* Set target to best high speed mode (D or QSPI). */
> +	ret = ad3552r_hs_set_target_io_mode_hs(st);
> +	if (ret)
> +		goto exit_err_ddr_mode;
> +
> +	/* Set bus to best high speed mode (D or QSPI). */
> +	ret = ad3552r_hs_set_bus_io_mode_hs(st);
> +	if (ret)
> +		goto exit_err_bus_mode_target;
> +
> +	/*
> +	 * Backend setup must be done now only, or related register values
> +	 * will be disrupted by previous bus accesses.
> +	 */
>  	ret = iio_backend_data_transfer_addr(st->back, val);
>  	if (ret)
> -		goto exit_err;
> +		goto exit_err_bus_mode_target;
>  
>  	ret = iio_backend_data_format_set(st->back, 0, &fmt);
>  	if (ret)
> -		goto exit_err;
> +		goto exit_err_bus_mode_target;
>  
>  	ret = iio_backend_data_stream_enable(st->back);
>  	if (ret)
> -		goto exit_err;
> +		goto exit_err_bus_mode_target;
>  
>  	return 0;
>  
> -exit_err:
> -	ad3552r_qspi_update_reg_bits(st,
> -				     AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
> -				     AD3552R_MASK_SPI_CONFIG_DDR,
> -				     0, 1);
> +exit_err_bus_mode_target:
> +	/* Back to simple SPI, not using update to avoid read. */
> +	st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_TRANSFER_REGISTER,
> +				FIELD_PREP(AD3552R_MASK_MULTI_IO_MODE,
> +					   AD3552R_SPI) |
> +				AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE, 1);
>  
> +	/*
> +	 * Back bus to simple SPI, this must be executed together with above
> +	 * target mode unwind, and can be done only after it.
> +	 */
> +	st->data->bus_set_io_mode(st->back, AD3552R_IO_MODE_SPI);
> +
> +exit_err_ddr_mode:
>  	iio_backend_ddr_disable(st->back);
>  
> +exit_err_ddr_mode_target:
> +	/*
> +	 * Back to SDR.

Odd place for line break.

> +	 * In DDR we cannot read, whatever the mode is, so not using update.
> +	 */
> +	st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
> +				FIELD_PREP(AD3552R_MASK_SDO_DRIVE_STRENGTH, 1),
> +				1);
> +
> +exit_err_streaming:
> +	/* Back to single instruction mode, disabling loop. */
> +	st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_INTERFACE_CONFIG_B,
> +				AD3552R_MASK_SINGLE_INST |
> +				AD3552R_MASK_SHORT_INSTRUCTION, 1);
> +
>  	return ret;
>  }
>  
> @@ -193,11 +332,22 @@ static int ad3552r_hs_buffer_predisable(struct iio_dev *indio_dev)
>  	if (ret)
>  		return ret;
>  
> -	/* Inform DAC to set in SDR mode */
> -	ret = ad3552r_qspi_update_reg_bits(st,
> -					   AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
> -					   AD3552R_MASK_SPI_CONFIG_DDR,
> -					   0, 1);
> +	/*
> +	 * Set us to simple SPI, even if still in ddr, so to be able
> +	 * to write in primary region.
> +	 */
> +	ret = st->data->bus_set_io_mode(st->back, AD3552R_IO_MODE_SPI);
> +	if (ret)
> +		return ret;
> +
> +	/*
> +	 * Back to SDR
> +	 * (in DDR we cannot read, whatever the mode is, so not using update).
> +	 */
> +	st->config_d &= ~AD3552R_MASK_SPI_CONFIG_DDR;
> +	ret = st->data->bus_reg_write(st->back,
> +				      AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
> +				      st->config_d, 1);
>  	if (ret)
>  		return ret;
>  
> @@ -205,11 +355,21 @@ static int ad3552r_hs_buffer_predisable(struct iio_dev *indio_dev)
>  	if (ret)
>  		return ret;
>  
> -	/* Back to single instruction mode, disabling loop. */
> +	/*
> +	 * Back to simple SPI for secondary region too now,
> +	 * so to be able to dump/read registers there too if needed.
> +	 */
>  	ret = ad3552r_qspi_update_reg_bits(st,
> -					   AD3552R_REG_ADDR_INTERFACE_CONFIG_B,
> -					   AD3552R_MASK_SINGLE_INST,
> -					   AD3552R_MASK_SINGLE_INST, 1);
> +					   AD3552R_REG_ADDR_TRANSFER_REGISTER,
> +					   AD3552R_MASK_MULTI_IO_MODE,
> +					   AD3552R_SPI, 1);
> +	if (ret)
> +		return ret;
> +
> +	/* Back to single instruction mode, disabling loop. */
> +	ret = ad3552r_update_reg_bits(st, AD3552R_REG_ADDR_INTERFACE_CONFIG_B,

I think this commit will fail to compile with this rename.

ad3552r_qspi_update_reg_bits -> ad3552r_update_reg_bits

This functinon isn't renamed until the next patch.

> +				      AD3552R_MASK_SINGLE_INST,
> +				      AD3552R_MASK_SINGLE_INST, 1);
>  	if (ret)
>  		return ret;
>  
> @@ -319,6 +479,7 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
>  	if (ret)
>  		return ret;
>  
> +	/* HDL starts with DDR enabled, disabling it. */
>  	ret = iio_backend_ddr_disable(st->back);
>  	if (ret)
>  		return ret;
> @@ -352,6 +513,8 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
>  			 "Chip ID mismatch, detected 0x%x but expected 0x%x\n",
>  			 id, st->model_data->chip_id);
>  
> +	dev_info(st->dev, "chip id %s detected", st->model_data->model_name);

IIRC, Jonathan suggested dev_dbg() here.

> +
>  	/* Clear reset error flag, see ad3552r manual, rev B table 38. */
>  	ret = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_ERR_STATUS,
>  				      AD3552R_MASK_RESET_STATUS, 1);
> @@ -364,14 +527,6 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
>  	if (ret)
>  		return ret;
>  
> -	ret = st->data->bus_reg_write(st->back,
> -				AD3552R_REG_ADDR_TRANSFER_REGISTER,
> -				FIELD_PREP(AD3552R_MASK_MULTI_IO_MODE,
> -					   AD3552R_QUAD_SPI) |
> -				AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE, 1);
> -	if (ret)
> -		return ret;
> -
>  	ret = iio_backend_data_source_set(st->back, 0, IIO_BACKEND_EXTERNAL);
>  	if (ret)
>  		return ret;
> @@ -528,6 +683,9 @@ static int ad3552r_hs_probe(struct platform_device *pdev)
>  }
>  
>  static const struct of_device_id ad3552r_hs_of_id[] = {
> +	{ .compatible = "adi,ad3541r", .data = &ad3541r_model_data },
> +	{ .compatible = "adi,ad3542r", .data = &ad3542r_model_data },
> +	{ .compatible = "adi,ad3551r", .data = &ad3551r_model_data },
>  	{ .compatible = "adi,ad3552r", .data = &ad3552r_model_data },
>  	{ }
>  };
> diff --git a/drivers/iio/dac/ad3552r.h b/drivers/iio/dac/ad3552r.h
> index 23f038464a0c..9d450019ece9 100644
> --- a/drivers/iio/dac/ad3552r.h
> +++ b/drivers/iio/dac/ad3552r.h
> @@ -132,6 +132,8 @@
>  
>  #define AD3552R_MAX_RANGES	5
>  #define AD3542R_MAX_RANGES	5
> +#define AD3552R_SPI		0
> +#define AD3552R_DUAL_SPI	1
>  #define AD3552R_QUAD_SPI	2
>  
>  extern const s32 ad3552r_ch_ranges[AD3552R_MAX_RANGES][2];
> @@ -156,6 +158,7 @@ struct ad3552r_model_data {
>  	const s32 (*ranges_table)[2];
>  	int num_ranges;
>  	bool requires_output_range;
> +	int num_spi_data_lanes;
>  };
>  
>  struct ad3552r_ch_data {
> 

Re: [PATCH v2 9/9] iio: dac: ad3552r-hs: update function name (non functional)

[David Lechner]

On 1/8/25 11:29 AM, Angelo Dureghello wrote:
> From: Angelo Dureghello <adureghello@baylibre.com>
> 
> Update ad3552r_qspi_update_reg_bits function name to a more
> generic name, since used mode can be SIMPLE/DUAL/QUAD SPI.
> 
> Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
> ---

...

> @@ -247,7 +245,6 @@ static int ad3552r_hs_buffer_postenable(struct iio_dev *indio_dev)
>  	ret = st->data->bus_reg_write(st->back,
>  				      AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
>  				      st->config_d, 1);
> -

Stray blank line change. Probably should be squashed into earlier patch.

>  	if (ret)
>  		goto exit_err_streaming;
>  

Re: [PATCH v2 6/9] iio: dac: ad3552r-hs: use instruction mode for configuration

[Angelo Dureghello]

Hi,

On 08.01.2025 15:16, David Lechner wrote:
> On 1/8/25 11:29 AM, Angelo Dureghello wrote:
> > From: Angelo Dureghello <adureghello@baylibre.com>
> > 
> > Use "instruction" mode over initial configuration and all other
> > non-streaming operations.
> > 
> > DAC boots in streaming mode as default, and the driver is not
> > changing this mode.
> > 
> > Instruction r/w is still working becouse instruction is processed
> 
> s/becouse/because/
> 
> > from the DAC after chip select is deasserted, this works until
> > loop mode is 0 or greater than the instruction size.
> > 
> > All initial operations should be more safely done in instruction
> > mode, a mode provided for this.
> 
> I'm not sure it is really "safer". The way I read the datasheet, this just
> enables bulk reads of multiple registers. So unless we need to do bulk reads
> it seems like this is just adding extra complexity to the driver without a
> tangible benefit.
> 

this change was initially requested from the HDL team to stay aligned with
the HDL side streaming/non streaming mode, and later, applied since seems
a safer way to operate.

I see that for the driver and DAC point of view, this is "functionally"
not needed, but streaming mode for configuration or raw read/write works
until STREAM_MODE register is set to 0 or to a value >= to the register
size to be accessed, since the _CS deasserting completes the transaction.

I.e., a transaction with a STREAM_MODE set to 1 would fail in case of 
a 16bit r/w access. Staying into streaming mode seems to me a bit tricky,
and setting to instruction mode may be safer since in this mode the
STREAM_MODE value is not important anymore.

For me is the same, i can remove related code. As you prefer.

> > 
> > Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
> > ---
> >  drivers/iio/dac/ad3552r-hs.c | 22 ++++++++++++++++++++++
> >  1 file changed, 22 insertions(+)
> > 
> > diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c
> > index 27949f207d42..991b11702273 100644
> > --- a/drivers/iio/dac/ad3552r-hs.c
> > +++ b/drivers/iio/dac/ad3552r-hs.c
> > @@ -132,6 +132,13 @@ static int ad3552r_hs_buffer_postenable(struct iio_dev *indio_dev)
> >  		return -EINVAL;
> >  	}
> >  
> > +	/* Primary region access, set streaming mode (now in SPI + SDR). */
> > +	ret = ad3552r_qspi_update_reg_bits(st,
> > +					   AD3552R_REG_ADDR_INTERFACE_CONFIG_B,
> > +					   AD3552R_MASK_SINGLE_INST, 0, 1);
> 
> Missing undoing this operation in the error path if a later operation in this
> function fails?
> 
> > +	if (ret)
> > +		return ret;
> > +
> >  	ret = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_STREAM_MODE,
> >  				      loop_len, 1);
> >  	if (ret)
> 

Re: [PATCH v2 6/9] iio: dac: ad3552r-hs: use instruction mode for configuration

[David Lechner]

On 1/9/25 11:25 AM, Angelo Dureghello wrote:
> Hi,
> 
> On 08.01.2025 15:16, David Lechner wrote:
>> On 1/8/25 11:29 AM, Angelo Dureghello wrote:
>>> From: Angelo Dureghello <adureghello@baylibre.com>
>>>
>>> Use "instruction" mode over initial configuration and all other
>>> non-streaming operations.
>>>
>>> DAC boots in streaming mode as default, and the driver is not
>>> changing this mode.
>>>
>>> Instruction r/w is still working becouse instruction is processed
>>
>> s/becouse/because/
>>
>>> from the DAC after chip select is deasserted, this works until
>>> loop mode is 0 or greater than the instruction size.
>>>
>>> All initial operations should be more safely done in instruction
>>> mode, a mode provided for this.
>>
>> I'm not sure it is really "safer". The way I read the datasheet, this just
>> enables bulk reads of multiple registers. So unless we need to do bulk reads
>> it seems like this is just adding extra complexity to the driver without a
>> tangible benefit.
>>
> 
> this change was initially requested from the HDL team to stay aligned with
> the HDL side streaming/non streaming mode, and later, applied since seems
> a safer way to operate.
> 
> I see that for the driver and DAC point of view, this is "functionally"
> not needed, but streaming mode for configuration or raw read/write works
> until STREAM_MODE register is set to 0 or to a value >= to the register
> size to be accessed, since the _CS deasserting completes the transaction.
> 
> I.e., a transaction with a STREAM_MODE set to 1 would fail in case of 
> a 16bit r/w access. Staying into streaming mode seems to me a bit tricky,
> and setting to instruction mode may be safer since in this mode the
> STREAM_MODE value is not important anymore.
> 
> For me is the same, i can remove related code. As you prefer.
> 
If it really does make a difference, I'm OK to keep it.

Re: [PATCH v2 1/9] iio: dac: ad3552r-common: fix ad3541/2r ranges

[Jonathan Cameron]

On Wed, 8 Jan 2025 14:43:22 -0600
David Lechner <dlechner@baylibre.com> wrote:

> On 1/8/25 11:29 AM, Angelo Dureghello wrote:
> > From: Angelo Dureghello <adureghello@baylibre.com>
> > 
> > Fix ad3541/2r voltage ranges to be as per ad3542r datasheet,
> > rev. C, table 38 (page 57).
> > 
> > The wrong ad354xr ranges was generating erroneous Vpp output.
> > 
> > In more details:
> > - fix wrong number of ranges, they are 5 ranges, not 6,
> > - remove non-existent 0-3V range,
> > - adjust order, since ad3552r_find_range() get a wrong index,
> >   producing a wrong Vpp as output.
> > 
> > Retested all the ranges on real hardware, EVALAD3542RFMCZ:
> > 
> > adi,output-range-microvolt (fdt):
> > <(000000) (2500000)>;   ok (Rfbx1, switch 10)
> > <(000000) (5000000)>;   ok (Rfbx1, switch 10)
> > <(000000) (10000000)>;  ok (Rfbx1, switch 10)
> > <(-5000000) (5000000)>; ok (Rfbx2, switch +/- 5)
> > <(-2500000) (7500000)>; ok (Rfbx2, switch -2.5/7.5)
> > 
> > Fixes: 8f2b54824b28 ("drivers:iio:dac: Add AD3552R driver support")
> > Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
> > ---  
> Reviewed-by: David Lechner <dlechner@baylibre.com>
> 

Applied to the fixes-togreg branch of iio.git and marked for stable.

Thanks,

Jonathan

Re: [PATCH v2 2/9] iio: dac: ad3552r-hs: clear reset status flag

[Jonathan Cameron]

On Wed, 8 Jan 2025 14:51:00 -0600
David Lechner <dlechner@baylibre.com> wrote:

> On 1/8/25 11:29 AM, Angelo Dureghello wrote:
> > From: Angelo Dureghello <adureghello@baylibre.com>
> > 
> > Clear reset status flag, to keep error status register
> > clean after reset (ad3552r manual, rev B table 38).
> > 
> > Reset error flag was left to 1, so debugging registers, the
> > "Error Status Register" was dirty (0x01). It is important
> > to clear this bit, so if there is any reset event over normal
> > working mode, it is possible to detect it.  
> 
> Do we need to do the same for ad3552r.c as well? Separate patch of course.
> 
> > 
> > Fixes: 0b4d9fe58be8 ("iio: dac: ad3552r: add high-speed platform driver")
> > Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
> > ---  
> Reviewed-by: David Lechner <dlechner@baylibre.com>
> 

Applied to the fixes-togreg branch of iio.git and marked for stable.

Re: [PATCH v2 5/9] iio: dac: ad3552r-hs: fix message on wrong chip id

[Jonathan Cameron]

On Wed, 08 Jan 2025 18:29:19 +0100
Angelo Dureghello <adureghello@baylibre.com> wrote:

> From: Angelo Dureghello <adureghello@baylibre.com>
> 
> Set a better info message on wrong chip id, fixing the
> expected value as read from the info struct.
Trivial but please wrap closer to 75 chars.
Makes not difference here, but in long logs of commits
it can help and it is good to be consistent.

Jonathan

> 
> Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
> ---
>  drivers/iio/dac/ad3552r-hs.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c
> index 8974df625670..27949f207d42 100644
> --- a/drivers/iio/dac/ad3552r-hs.c
> +++ b/drivers/iio/dac/ad3552r-hs.c
> @@ -326,8 +326,9 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
>  
>  	id |= val << 8;
>  	if (id != st->model_data->chip_id)
> -		dev_info(st->dev, "Chip ID error. Expected 0x%x, Read 0x%x\n",
> -			 AD3552R_ID, id);
> +		dev_info(st->dev,
> +			 "Chip ID mismatch, detected 0x%x but expected 0x%x\n",
> +			 id, st->model_data->chip_id);
>  
>  	/* Clear reset error flag, see ad3552r manual, rev B table 38. */
>  	ret = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_ERR_STATUS,
> 

Re: [PATCH v2 8/9] iio: dac: ad3552r-hs: add ad3541/2r support

[Jonathan Cameron]

On Wed, 08 Jan 2025 18:29:22 +0100
Angelo Dureghello <adureghello@baylibre.com> wrote:

> From: Angelo Dureghello <adureghello@baylibre.com>
> 
> A new fpga HDL has been developed from ADI to support ad354xr
> devices.
> 
> Add support for ad3541r and ad3542r with following additions:
> 
> - use common device_info structures for hs and non hs drivers,
> - DMA buffering, use DSPI mode for ad354xr and QSPI for ad355xr,
> - change samplerate to respect number of lanes.
> 
> Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>

One question inline.  I also wonder if you can easily add checks
that mean any spurious (bug) read in DDR mode would get an error
print to tell who ever triggered it what went wrong.

Jonathan

> diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c
> index bfb6228c9b9b..5995bab6a9b1 100644
> --- a/drivers/iio/dac/ad3552r-hs.c
> +++ b/drivers/iio/dac/ad3552r-hs.c

> +
> +static int ad3552r_hs_set_target_io_mode_hs(struct ad3552r_hs_state *st)
> +{
> +	int mode_target;
> +
> +	/*
> +	 * Best access for secondary reg area, QSPI where possible,
> +	 * else as DSPI.
> +	 */
> +	if (st->model_data->num_spi_data_lanes == 4)
> +		mode_target = AD3552R_QUAD_SPI;
> +	else
> +		mode_target = AD3552R_DUAL_SPI;
> +
> +	/*
> +	 * Better to not use update here, since generally it is already
> +	 * set as DDR mode, and it's not possible to read in DDR mode.
> +	 */
> +	return st->data->bus_reg_write(st->back,
> +				AD3552R_REG_ADDR_TRANSFER_REGISTER,
> +				FIELD_PREP(AD3552R_MASK_MULTI_IO_MODE,
> +					   mode_target) |
> +				AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE, 1);
> +}

> @@ -319,6 +479,7 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
>  	if (ret)
>  		return ret;
>  
> +	/* HDL starts with DDR enabled, disabling it. */
>  	ret = iio_backend_ddr_disable(st->back);
>  	if (ret)
>  		return ret;
> @@ -352,6 +513,8 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
>  			 "Chip ID mismatch, detected 0x%x but expected 0x%x\n",
>  			 id, st->model_data->chip_id);
>  
> +	dev_info(st->dev, "chip id %s detected", st->model_data->model_name);
> +
>  	/* Clear reset error flag, see ad3552r manual, rev B table 38. */
>  	ret = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_ERR_STATUS,
>  				      AD3552R_MASK_RESET_STATUS, 1);
> @@ -364,14 +527,6 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
>  	if (ret)
>  		return ret;
>  
> -	ret = st->data->bus_reg_write(st->back,
> -				AD3552R_REG_ADDR_TRANSFER_REGISTER,
> -				FIELD_PREP(AD3552R_MASK_MULTI_IO_MODE,
> -					   AD3552R_QUAD_SPI) |
> -				AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE, 1);
> -	if (ret)
> -		return ret;
> -
This is the call you just added to ensure we end up in instruction mode.
I'm not seeing another place it is now called so is this an accidental revert?
If it is intentional then break out a patch that deals with that change
before the addition of new parts.

I was expecting to see a call to _set_target_io_mode_hs.



>  	ret = iio_backend_data_source_set(st->back, 0, IIO_BACKEND_EXTERNAL);
>  	if (ret)
>  		return ret;
> @@ -528,6 +683,9 @@ static int ad3552r_hs_probe(struct platform_device *pdev)
>  }

Re: [PATCH v2 8/9] iio: dac: ad3552r-hs: add ad3541/2r support

[Angelo Dureghello]

On 12.01.2025 14:36, Jonathan Cameron wrote:
> On Wed, 08 Jan 2025 18:29:22 +0100
> Angelo Dureghello <adureghello@baylibre.com> wrote:
> 
> > From: Angelo Dureghello <adureghello@baylibre.com>
> > 
> > A new fpga HDL has been developed from ADI to support ad354xr
> > devices.
> > 
> > Add support for ad3541r and ad3542r with following additions:
> > 
> > - use common device_info structures for hs and non hs drivers,
> > - DMA buffering, use DSPI mode for ad354xr and QSPI for ad355xr,
> > - change samplerate to respect number of lanes.
> > 
> > Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
> 
> One question inline.  I also wonder if you can easily add checks
> that mean any spurious (bug) read in DDR mode would get an error
> print to tell who ever triggered it what went wrong.
> 
> Jonathan
> 
> > diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c
> > index bfb6228c9b9b..5995bab6a9b1 100644
> > --- a/drivers/iio/dac/ad3552r-hs.c
> > +++ b/drivers/iio/dac/ad3552r-hs.c
> 
> > +
> > +static int ad3552r_hs_set_target_io_mode_hs(struct ad3552r_hs_state *st)
> > +{
> > +	int mode_target;
> > +
> > +	/*
> > +	 * Best access for secondary reg area, QSPI where possible,
> > +	 * else as DSPI.
> > +	 */
> > +	if (st->model_data->num_spi_data_lanes == 4)
> > +		mode_target = AD3552R_QUAD_SPI;
> > +	else
> > +		mode_target = AD3552R_DUAL_SPI;
> > +
> > +	/*
> > +	 * Better to not use update here, since generally it is already
> > +	 * set as DDR mode, and it's not possible to read in DDR mode.
> > +	 */
> > +	return st->data->bus_reg_write(st->back,
> > +				AD3552R_REG_ADDR_TRANSFER_REGISTER,
> > +				FIELD_PREP(AD3552R_MASK_MULTI_IO_MODE,
> > +					   mode_target) |
> > +				AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE, 1);
> > +}
> 
> > @@ -319,6 +479,7 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
> >  	if (ret)
> >  		return ret;
> >  
> > +	/* HDL starts with DDR enabled, disabling it. */
> >  	ret = iio_backend_ddr_disable(st->back);
> >  	if (ret)
> >  		return ret;
> > @@ -352,6 +513,8 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
> >  			 "Chip ID mismatch, detected 0x%x but expected 0x%x\n",
> >  			 id, st->model_data->chip_id);
> >  
> > +	dev_info(st->dev, "chip id %s detected", st->model_data->model_name);
> > +
> >  	/* Clear reset error flag, see ad3552r manual, rev B table 38. */
> >  	ret = st->data->bus_reg_write(st->back, AD3552R_REG_ADDR_ERR_STATUS,
> >  				      AD3552R_MASK_RESET_STATUS, 1);
> > @@ -364,14 +527,6 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st)
> >  	if (ret)
> >  		return ret;
> >  
> > -	ret = st->data->bus_reg_write(st->back,
> > -				AD3552R_REG_ADDR_TRANSFER_REGISTER,
> > -				FIELD_PREP(AD3552R_MASK_MULTI_IO_MODE,
> > -					   AD3552R_QUAD_SPI) |
> > -				AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE, 1);
> > -	if (ret)
> > -		return ret;
> > -
> This is the call you just added to ensure we end up in instruction mode.
> I'm not seeing another place it is now called so is this an accidental revert?
> If it is intentional then break out a patch that deals with that change
> before the addition of new parts.
> 
> I was expecting to see a call to _set_target_io_mode_hs.
> 
>
The above was only related the IO mode, it was set for QSPI. Now the mode
is kept as simple SPI for all the configurations, moving to DSPI or QSPI
later for streaming.
 
> 
> >  	ret = iio_backend_data_source_set(st->back, 0, IIO_BACKEND_EXTERNAL);
> >  	if (ret)
> >  		return ret;
> > @@ -528,6 +683,9 @@ static int ad3552r_hs_probe(struct platform_device *pdev)
> >  }