Files
linux-cryptodev-2.6/Documentation/userspace-api/gpio/sysfs.rst
Huichun Feng 7f1e45f4ae docs: gpio: prefer pread(2) for interrupt reading
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@gmail.com>
Link: https://lore.kernel.org/r/20240609173728.2950808-1-foxhoundsk.tw@gmail.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-06-10 09:37:52 +02:00

6.5 KiB