Re: [PATCH] docs: gpio: prefer pread(2) for interrupt reading

From: Bartosz Golaszewski
Date: Mon May 27 2024 - 11:14:19 EST


On Tue, May 14, 2024 at 6:12 AM Huichun Feng <foxhoundsk.tw@xxxxxxxxx> wrote:
>
> In legacy sysfs GPIO, when using poll(2) on the sysfs GPIO value for
> state change awaiting, a subsequent read(2) is required for consuming
> the event, which the doc recommends the use of lseek(2) or
> close-and-reopen to reset the file offset afterwards.
>
> The recommendations however, require at least 2 syscalls to consume
> the event. Gladly, use of pread(2) require only 1 syscall for the
> consumption. Let's advertise this usage by prioritizing its placement.
>
> Signed-off-by: Huichun Feng <foxhoundsk.tw@xxxxxxxxx>
> ---

This doesn't apply on top of gpio/for-next, please rebase and resend.

Bart