Documentation: ABI: IIO: add new convdelay documentation

Add new IIO "convdelay" documentation.

The ad7606 implements a phase calibation feature, in nanoseconds.
Being this a time delay, using the convdelay suffix.

Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20250606-wip-bl-ad7606-calibration-v9-1-6e014a1f92a2@baylibre.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
index ef52c427a015cf47bb9847782e13afbee01e9f31..3bc386995fb6ddf5fd0718587a84d703cb973d70 100644 (file)
--- a/Documentation/ABI/testing/sysfs-bus-iio
+++ b/Documentation/ABI/testing/sysfs-bus-iio
@@ -559,6 +559,30 @@ Description:
                - a small discrete set of values like "0 2 4 6 8"
                - a range specified as "[min step max]"
 
+What:          /sys/bus/iio/devices/iio:deviceX/in_voltageY_convdelay
+KernelVersion: 6.17
+Contact:       linux-iio@vger.kernel.org
+Description:
+               Delay of start of conversion from common reference point shared
+               by all channels. Can be writable when used to compensate for
+               delay variation introduced by external filters feeding a
+               simultaneous sampling ADC.
+
+               E.g., for the ad7606 ADC series, this value is intended as a
+               configurable time delay in seconds, to correct delay introduced
+               by an optional external filtering circuit.
+
+What:          /sys/bus/iio/devices/iio:deviceX/in_voltageY_convdelay_available
+KernelVersion: 6.16
+Contact:       linux-iio@vger.kernel.org
+Description:
+               Available values of convdelay. Maybe expressed as:
+
+               - a range specified as "[min step max]"
+
+               If shared across all channels, <type>_convdelay_available
+               is used.
+
 What:          /sys/bus/iio/devices/iio:deviceX/in_accel_x_calibscale
 What:          /sys/bus/iio/devices/iio:deviceX/in_accel_y_calibscale
 What:          /sys/bus/iio/devices/iio:deviceX/in_accel_z_calibscale