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authorWolfram Sang <w.sang@pengutronix.de>2011-01-12 17:00:23 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2011-01-13 08:03:14 -0800
commit0fdae42d361bbb431ca0ab0efed5126a94821177 (patch)
tree958a045aca3e40ca487dac67597496a7ed885115 /Documentation/gpio.txt
parent49a367937fe4250144e24440e5a11ae4344202b1 (diff)
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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 792faa3..a492d92 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:
int gpio_direction_input(unsigned gpio);
int gpio_direction_output(unsigned gpio, int value);
-The return value is zero for success, else a negative errno. It should
+The return value is zero for success, else a negative errno. It must
be checked, since the get/set calls don't have error returns and since
misconfiguration is possible. You should normally issue these calls from
a task context. However, for spinlock-safe GPIOs it's OK to use them
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