From 9aac1e336c3ab3824f646224f4b2309b63c51668 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Fri, 15 Feb 2019 09:17:36 +0100 Subject: [PATCH] Documentation: gpio: legacy: Don't use POLLERR for poll(2) MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit According to the manpage of poll(2) and also looking at the respective syscall providing POLLERR in .events is a no-op. So don't recommend using it. Signed-off-by: Uwe Kleine-König Reviewed-by: Bartosz Golaszewski Signed-off-by: Linus Walleij --- Documentation/driver-api/gpio/legacy.rst | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/Documentation/driver-api/gpio/legacy.rst b/Documentation/driver-api/gpio/legacy.rst index 5e9421e05f1d..9bc34ba697d9 100644 --- a/Documentation/driver-api/gpio/legacy.rst +++ b/Documentation/driver-api/gpio/legacy.rst @@ -690,11 +690,10 @@ and have the following read/write attributes: and if it has been configured to generate interrupts (see the description of "edge"), you can poll(2) on that file and poll(2) will return whenever the interrupt was triggered. If - you use poll(2), set the events POLLPRI and POLLERR. If you - use select(2), set the file descriptor in exceptfds. After - poll(2) returns, either lseek(2) to the beginning of the sysfs - file and read the new value or close the file and re-open it - to read the value. + you use poll(2), set the events POLLPRI. If you use select(2), + set the file descriptor in exceptfds. After poll(2) returns, + either lseek(2) to the beginning of the sysfs file and read the + new value or close the file and re-open it to read the value. "edge" ... reads as either "none", "rising", "falling", or "both". Write these strings to select the signal edge(s) -- 2.30.2