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authorLinus Walleij <linus.walleij@linaro.org>2015-08-10 11:51:46 +0200
committerLinus Walleij <linus.walleij@linaro.org>2015-08-13 13:13:16 +0200
commit77a775b7ccaf86b0bb67ceaaf3b6d2720e12b506 (patch)
treec4f590a11a1ca14be21e57f01c85ce501296a2a2 /Documentation/ABI/testing/sysfs-gpio
parent29b5357d25ba1528531ef9532b5743a32fdf8cd2 (diff)
downloadlwn-77a775b7ccaf86b0bb67ceaaf3b6d2720e12b506.tar.gz
lwn-77a775b7ccaf86b0bb67ceaaf3b6d2720e12b506.zip
gpio/ABI: document what is already the case
commit 926b663ce8215ba448960e1ff6e58b67a2c3b99b "gpiolib: allow GPIOs to be named" added the ability to name GPIO lines by an array of names stored in the GPIO chip. This was in 2009 and has been an ABI since. Let's document it properly. Cc: Daniel Silverstone <dsilvers@digital-scurf.org> Cc: Markus Pargmann <mpa@pengutronix.de> Cc: Johan Hovold <johan@kernel.org> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'Documentation/ABI/testing/sysfs-gpio')
-rw-r--r--Documentation/ABI/testing/sysfs-gpio3
1 files changed, 2 insertions, 1 deletions
diff --git a/Documentation/ABI/testing/sysfs-gpio b/Documentation/ABI/testing/sysfs-gpio
index 80f4c94c7bef..55ffa2df1c10 100644
--- a/Documentation/ABI/testing/sysfs-gpio
+++ b/Documentation/ABI/testing/sysfs-gpio
@@ -16,7 +16,8 @@ Description:
/sys/class/gpio
/export ... asks the kernel to export a GPIO to userspace
/unexport ... to return a GPIO to the kernel
- /gpioN ... for each exported GPIO #N
+ /gpioN ... for each exported GPIO #N OR
+ /<LINE-NAME> ... for a properly named GPIO line
/value ... always readable, writes fail for input GPIOs
/direction ... r/w as: in, out (default low); write: high, low
/edge ... r/w as: none, falling, rising, both