iio: adc: ad7192: Add sysfs ABI documentation

Add initial ABI documentation for ad7192 adc sysfs interfaces.

Signed-off-by: Mircea Caprioru <mircea.caprioru@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-adc-ad7192 b/Documentation/ABI/testing/sysfs-bus-iio-adc-ad7192
new file mode 100644 (file)
index 0000000..74a2873
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-iio-adc-ad7192
@@ -0,0 +1,15 @@
+What:          /sys/bus/iio/devices/iio:deviceX/ac_excitation_en
+KernelVersion:
+Contact:       linux-iio@vger.kernel.org
+Description:
+               Reading gives the state of AC excitation.
+               Writing '1' enables AC excitation.
+
+What:          /sys/bus/iio/devices/iio:deviceX/bridge_switch_en
+KernelVersion:
+Contact:       linux-iio@vger.kernel.org
+Description:
+               This bridge switch is used to disconnect it when there is a
+               need to minimize the system current consumption.
+               Reading gives the state of the bridge switch.
+               Writing '1' enables the bridge switch.