iio: ph: add IIO_PH channel type
Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
index 8fadd27..80c6fce 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio
+++ b/Documentation/ABI/testing/sysfs-bus-iio
@@ -1493,3 +1493,10 @@
This ABI is especially applicable for humidity sensors
to heatup the device and get rid of any condensation
in some humidity environment
+
+What: /sys/bus/iio/devices/iio:deviceX/in_ph_raw
+KernelVersion: 4.5
+Contact: linux-iio@vger.kernel.org
+Description:
+ Raw (unscaled no offset etc.) pH reading of a substance as a negative
+ base-10 logarithm of hydrodium ions in a litre of water.