[PATCH v3 1/8] Documentation: ABI: add oversampling frequency in sysfs-bus-iio

From: Jorge Marques
Date: Tue Jun 10 2025 - 03:36:05 EST


Some devices have an internal clock used to space out the conversion
trigger for the oversampling filter, Consider an ADC with conversion and
data ready pins topology:

Sampling trigger | | | | |
ADC conversion ++++ ++++ ++++ ++++ ++++
ADC data ready * * * * *

With the oversampling frequency, conversions are spaced:

Sampling trigger | | | | |
ADC conversion + + + + + + + + + + + + + + + + + + + +
ADC data ready * * * * *

In some devices and ranges, this internal clock can be used to evenly
space the conversions between the sampling edge. In other devices the
oversampling frequency is fixed or is computed based on the sampling
frequency parameter, and the parameter is read only.

Signed-off-by: Jorge Marques <jorge.marques@xxxxxxxxxx>
---
Documentation/ABI/testing/sysfs-bus-iio | 17 +++++++++++++++++
1 file changed, 17 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
index ef52c427a015cf47bb9847782e13afbee01e9f31..e60367255be89a9acc827ec1a749b729735f60e6 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio
+++ b/Documentation/ABI/testing/sysfs-bus-iio
@@ -139,6 +139,23 @@ Contact: linux-iio@xxxxxxxxxxxxxxx
Description:
Hardware dependent values supported by the oversampling filter.

+What: /sys/bus/iio/devices/iio:deviceX/oversampling_frequency
+KernelVersion: 6.17
+Contact: linux-iio@xxxxxxxxxxxxxxx
+Description:
+ Some devices have internal clocks for oversampling.
+ Sets the resulting frequency in Hz to trigger a conversion used by
+ the oversampling filter.
+ If the device has a fixed internal clock or is computed based on
+ the sampling frequency parameter, the parameter is read only.
+
+What: /sys/bus/iio/devices/iio:deviceX/oversampling_frequency_available
+KernelVersion: 6.17
+Contact: linux-iio@xxxxxxxxxxxxxxx
+Description:
+ Hardware dependent values supported by the oversampling
+ frequency.
+
What: /sys/bus/iio/devices/iio:deviceX/in_voltageY_raw
What: /sys/bus/iio/devices/iio:deviceX/in_voltageY_supply_raw
What: /sys/bus/iio/devices/iio:deviceX/in_voltageY_i_raw

--
2.49.0