Re: [RFC 08/11] gpiolib: cdev: Add hardware timestamp clock type

On Sat, Jun 26, 2021 at 1:48 AM Dipen Patel [off-list ref] wrote:

This patch adds new clock type for the GPIO controller which can
timestamp gpio lines using hardware means. To expose such
functionalities to the userspace, code has been added in this patch
where during line create call, it checks for new clock type and if
requested, calls hardware timestamp related API from gpiolib.c.
During line change event, it retrieves timestamp in nano seconds by
calling gpiod_get_hw_timestamp API from gpiolib.c. At the line release,
it disables this functionality by calling gpiod_hw_timestamp_control.

Signed-off-by: Dipen Patel <dipenp@nvidia.com>

This looks good to me, pretty much exactly as I imagine it should be
done, and it is also nice that we only implement it
for the v2 UAPI.

Yours,
Linus Walleij