[PATCH v2 1/3] iio: types: add IIO_VOLUMEFLOW channel type

[Wadim Mueller <wafgo01@gmail.com>]

Add a new IIO channel type for liquid volumetric flow sensors.  The
unit exposed via the standard _scale attribute is litres per second
(l/s), so drivers reporting smaller native units (e.g. ml/min) only
need to set a fractional scale.

Update iio-core's name table, the iio_event_monitor whitelist and
the sysfs-bus-iio ABI document to match.  The new _scale attribute is
folded into the existing shared _scale block; only the per-type _raw
needs a fresh entry.

Signed-off-by: Wadim Mueller <wafgo01@gmail.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Jean Delvare <jdelvare@suse.com>
Cc: Andreas Klinger <ak@it-klinger.de>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: linux-hwmon@vger.kernel.org
Cc: Maxwell Doose <m32285159@gmail.com>
---
 Documentation/ABI/testing/sysfs-bus-iio | 11 +++++++++++
 drivers/iio/industrialio-core.c         |  1 +
 include/uapi/linux/iio/types.h          |  1 +
 tools/iio/iio_event_monitor.c           |  2 ++
 4 files changed, 15 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
index 5f87dcee7..2188557cb 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio
+++ b/Documentation/ABI/testing/sysfs-bus-iio
@@ -507,6 +507,8 @@ What:		/sys/bus/iio/devices/iio:deviceX/in_intensity_red_scale
 What:		/sys/bus/iio/devices/iio:deviceX/in_intensity_green_scale
 What:		/sys/bus/iio/devices/iio:deviceX/in_intensity_blue_scale
 What:		/sys/bus/iio/devices/iio:deviceX/in_concentration_co2_scale
+What:		/sys/bus/iio/devices/iio:deviceX/in_volumeflow_scale
+What:		/sys/bus/iio/devices/iio:deviceX/in_volumeflowY_scale
 KernelVersion:	2.6.35
 Contact:	linux-iio@vger.kernel.org
 Description:
@@ -2458,3 +2460,12 @@ Description:
 		seconds, expressed as:
 
 		- a range specified as "[min step max]"
+
+What:		/sys/bus/iio/devices/iio:deviceX/in_volumeflow_raw
+What:		/sys/bus/iio/devices/iio:deviceX/in_volumeflowY_raw
+KernelVersion:	6.19
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Raw (unscaled) volumetric flow rate reading from the channel.
+		To convert to standard units (litres per second) apply the
+		channel's _scale (and _offset, when present).
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 22eefd048..aa34fcd8e 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -98,6 +98,7 @@ static const char * const iio_chan_type_name_spec[] = {
 	[IIO_CHROMATICITY] = "chromaticity",
 	[IIO_ATTENTION] = "attention",
 	[IIO_ALTCURRENT] = "altcurrent",
+	[IIO_VOLUMEFLOW] = "volumeflow",
 };
 
 static const char * const iio_modifier_names[] = {
diff --git a/include/uapi/linux/iio/types.h b/include/uapi/linux/iio/types.h
index 6d269b844..49480f321 100644
--- a/include/uapi/linux/iio/types.h
+++ b/include/uapi/linux/iio/types.h
@@ -53,6 +53,7 @@ enum iio_chan_type {
 	IIO_CHROMATICITY,
 	IIO_ATTENTION,
 	IIO_ALTCURRENT,
+	IIO_VOLUMEFLOW,
 };
 
 enum iio_modifier {
diff --git a/tools/iio/iio_event_monitor.c b/tools/iio/iio_event_monitor.c
index 03ca33869..078004750 100644
--- a/tools/iio/iio_event_monitor.c
+++ b/tools/iio/iio_event_monitor.c
@@ -65,6 +65,7 @@ static const char * const iio_chan_type_name_spec[] = {
 	[IIO_CHROMATICITY] = "chromaticity",
 	[IIO_ATTENTION] = "attention",
 	[IIO_ALTCURRENT] = "altcurrent",
+	[IIO_VOLUMEFLOW] = "volumeflow",
 };
 
 static const char * const iio_ev_type_text[] = {
@@ -193,6 +194,7 @@ static bool event_is_known(struct iio_event_data *event)
 	case IIO_CHROMATICITY:
 	case IIO_ATTENTION:
 	case IIO_ALTCURRENT:
+	case IIO_VOLUMEFLOW:
 		break;
 	default:
 		return false;
-- 
2.52.0