aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/gpio.txt
diff options
context:
space:
mode:
authorWolfram Sang <w.sang@pengutronix.de>2011-01-12 20:00:23 -0500
committerLinus Torvalds <torvalds@linux-foundation.org>2011-01-13 11:03:14 -0500
commit0fdae42d361bbb431ca0ab0efed5126a94821177 (patch)
tree958a045aca3e40ca487dac67597496a7ed885115 /Documentation/gpio.txt
parent49a367937fe4250144e24440e5a11ae4344202b1 (diff)
gpiolib: annotate gpio-intialization with __must_check
Because GPIOs can have crucial functions especially in embedded systems, we are better safe than sorry regarding their configuration. For gpio_request, the documentation is simply enforced: <quote>"The return value of gpio_request() must be checked."</quote> For gpio_direction_* and gpio_request_*, we now act accordingly. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Cc: David Brownell <dbrownell@users.sourceforge.net> Cc: Greg KH <gregkh@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Documentation/gpio.txt')
-rw-r--r--Documentation/gpio.txt2
1 files changed, 1 insertions, 1 deletions
diff --git a/Documentation/gpio.txt b/Documentation/gpio.txt
index 792faa3c06cf..a492d92bb098 100644
--- a/Documentation/gpio.txt
+++ b/Documentation/gpio.txt
@@ -135,7 +135,7 @@ setting up a platform_device using the GPIO, is mark its direction:
135 int gpio_direction_input(unsigned gpio); 135 int gpio_direction_input(unsigned gpio);
136 int gpio_direction_output(unsigned gpio, int value); 136 int gpio_direction_output(unsigned gpio, int value);
137 137
138The return value is zero for success, else a negative errno. It should 138The return value is zero for success, else a negative errno. It must
139be checked, since the get/set calls don't have error returns and since 139be checked, since the get/set calls don't have error returns and since
140misconfiguration is possible. You should normally issue these calls from 140misconfiguration is possible. You should normally issue these calls from
141a task context. However, for spinlock-safe GPIOs it's OK to use them 141a task context. However, for spinlock-safe GPIOs it's OK to use them