Re: [RFC PATCH 2/7] iio:ABI docs: Avoid repitition of triggerX/sampling_frequency
From: Lars-Peter Clausen <lars@metafoo.de>
Date: 2021-03-07 10:09:20
Also in:
linux-iio
On 1/17/21 4:38 PM, Jonathan Cameron wrote:
quoted hunk ↗ jump to hunk
From: Jonathan Cameron <Jonathan.Cameron@huawei.com> The timer-stm32 provided a little more specific information than the main docs about the value of 0 corresponding to stopping sampling. Given that this makes sense in general, move that statement over to the main docs and drop the version in sysfs-bus-iio-timer-stm32 Fixes $ scripts/get_abi.pl validate /sys/bus/iio/devices/triggerX/sampling_frequency is defined 2 times: ./Documentation/ABI/testing/sysfs-bus-iio-timer-stm32:92 ./Documentation/ABI/testing/sysfs-bus-iio:45 Cc: Fabrice Gasnier <redacted> Reported-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> --- Documentation/ABI/testing/sysfs-bus-iio | 2 ++ Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 | 8 -------- 2 files changed, 2 insertions(+), 8 deletions(-)diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio index d2dd9cc280f9..9b5ceb22363d 100644 --- a/Documentation/ABI/testing/sysfs-bus-iio +++ b/Documentation/ABI/testing/sysfs-bus-iio@@ -55,6 +55,8 @@ Description: direct access interfaces, it may be found in any of the relevant directories. If it affects all of the above then it is to be found in the base device directory. + Note a value 0 where supported, will correspond to sampling + stopping.
Hm, I don't like this. 0 should be an invalid value for the standard ABI. Enabling/disabling of the trigger should be controlled by whether there are any active trigger consumers. The stm32-timer-trigger implements a non-standard ABI and I think we need to document this explicitly. The driver does not have a set_state callback. So the frequency property is used to enable/disable the trigger, but as said above, for standard compliant triggers that should not be the case.