[PATCH v4 1/4] 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 cubic metres per
second (m^3/s), following the SI convention used by the other IIO
channel types.

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>
---
 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..e278fda4b 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:	7.3
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Raw (unscaled) volumetric flow rate reading from the channel.
+		To convert to standard units (cubic metres per second, m^3/s)
+		apply the channel's _scale (and _offset, when present).
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 93c7b8c46..571b8ba4e 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