From 3d599d1ca57f443e5c4ff5af1e69d90350082f77 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Uwe=20Kleine-K=C3=B6nig?=
 <ukleinek@informatik.uni-freiburg.de>
Date: Wed, 15 Oct 2008 22:03:12 -0700
Subject: [PATCH] gpio_free might sleep, generic part
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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>
---
 drivers/gpio/gpiolib.c | 2 ++
 include/linux/gpio.h   | 3 +++
 2 files changed, 5 insertions(+)

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;
diff --git a/include/linux/gpio.h b/include/linux/gpio.h
index 730a20b83576..e10c49a5b96e 100644
--- a/include/linux/gpio.h
+++ b/include/linux/gpio.h
@@ -8,6 +8,7 @@
 
 #else
 
+#include <linux/kernel.h>
 #include <linux/types.h>
 #include <linux/errno.h>
 
@@ -32,6 +33,8 @@ static inline int gpio_request(unsigned gpio, const char *label)
 
 static inline void gpio_free(unsigned gpio)
 {
+	might_sleep();
+
 	/* GPIO can never have been requested */
 	WARN_ON(1);
 }
-- 
2.20.1