On Thu, Jan 7, 2021 at 3:58 AM Kent Gibson [off-list ref] wrote:

The GPIO mockup selftests are overly complicated with separate
implementations of the tests for sysfs and cdev uAPI, and with the cdev
implementation being dependent on tools/gpio and libmount.

Rework the test implementation to provide a common test suite with a
simplified pluggable uAPI interface.  The cdev implementation utilises
the GPIO uAPI directly to remove the dependence on tools/gpio.
The simplified uAPI interface removes the need for any file system mount
checks in C, and so removes the dependence on libmount.

The rework also fixes the sysfs test implementation which has been broken
since the device created in the multiple gpiochip case was split into
separate devices.

Fixes: commit 8a39f597bcfd ("gpio: mockup: rework device probing")
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Acked-by: Linus Walleij <redacted>

The C part looks good to me. For the shell part I would probably do a
couple things differently but since we don't really have a coding
style for shell scripts in the kernel, I don't want to block these
patches, so:

Reviewed-by: Bartosz Golaszewski <redacted>