gpio_free might sleep, generic part

According to the documentation gpio_free should only be called from task
context only.  To make this more explicit add a might sleep to all
implementations.

This is the generic part which changes gpiolib and the fallback
implementation only.

Signed-off-by: Uwe Kleine-König <ukleinek@informatik.uni-freiburg.de>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 8d2940517c99..317004fd94fb 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -792,6 +792,8 @@ void gpio_free(unsigned gpio)
         unsigned long           flags;
         struct gpio_desc        *desc;
 
+        might_sleep();
+
         if (!gpio_is_valid(gpio)) {
                 WARN_ON(extra_checks);
                 return;