[ARM] gpio_free might sleep, arm architecture

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 patch changes the gpio_free implementations for the arm architecture.
 DaVinci is skipped on purpose to simplify the merge process for patches
switching it over to use gpiolib as per request by David Brownell.

Signed-off-by: Uwe Kleine-König <ukleinek@informatik.uni-freiburg.de>
Cc: David Brownell <david-b@pacbell.net>
Cc: Andrew Victor <linux@maxim.org.za>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

6 files changed, 15 insertions, 0 deletions

diff --git a/arch/arm/mach-at91/include/mach/gpio.h b/arch/arm/mach-at91/include/mach/gpio.h
index 76d76e2fa69..bffa6741a75 100644
--- a/arch/arm/mach-at91/include/mach/gpio.h
+++ b/arch/arm/mach-at91/include/mach/gpio.h
@@ -13,6 +13,7 @@
 #ifndef __ASM_ARCH_AT91RM9200_GPIO_H
 #define __ASM_ARCH_AT91RM9200_GPIO_H
 
+#include <linux/kernel.h>
 #include <asm/irq.h>
 
 #define PIN_BASE		NR_AIC_IRQS
@@ -220,6 +221,7 @@ static inline int gpio_request(unsigned gpio, const char *label)
 
 static inline void gpio_free(unsigned gpio)
 {
+	might_sleep();
 }
 
 extern int gpio_direction_input(unsigned gpio);
diff --git a/arch/arm/mach-imx/include/mach/gpio.h b/arch/arm/mach-imx/include/mach/gpio.h
index 6e3d795f226..502d5aa2c09 100644
--- a/arch/arm/mach-imx/include/mach/gpio.h
+++ b/arch/arm/mach-imx/include/mach/gpio.h
@@ -1,5 +1,6 @@
 #ifndef _IMX_GPIO_H
 
+#include <linux/kernel.h>
 #include <mach/imx-regs.h>
 
 #define IMX_GPIO_ALLOC_MODE_NORMAL	0
@@ -63,6 +64,8 @@ static inline int gpio_request(unsigned gpio, const char *label)
 
 static inline void gpio_free(unsigned gpio)
 {
+	might_sleep();
+
 	imx_gpio_free(gpio);
 }
 
diff --git a/arch/arm/mach-ixp4xx/include/mach/gpio.h b/arch/arm/mach-ixp4xx/include/mach/gpio.h
index 9fbde177920..cd5aec26c07 100644
--- a/arch/arm/mach-ixp4xx/include/mach/gpio.h
+++ b/arch/arm/mach-ixp4xx/include/mach/gpio.h
@@ -25,6 +25,7 @@
 #ifndef __ASM_ARCH_IXP4XX_GPIO_H
 #define __ASM_ARCH_IXP4XX_GPIO_H
 
+#include <linux/kernel.h>
 #include <mach/hardware.h>
 
 static inline int gpio_request(unsigned gpio, const char *label)
@@ -34,6 +35,8 @@ static inline int gpio_request(unsigned gpio, const char *label)
 
 static inline void gpio_free(unsigned gpio)
 {
+	might_sleep();
+
 	return;
 }
 
diff --git a/arch/arm/mach-ks8695/include/mach/gpio.h b/arch/arm/mach-ks8695/include/mach/gpio.h
index 73c84168761..d4af5c335f1 100644
--- a/arch/arm/mach-ks8695/include/mach/gpio.h
+++ b/arch/arm/mach-ks8695/include/mach/gpio.h
@@ -11,6 +11,8 @@
 #ifndef __ASM_ARCH_GPIO_H_
 #define __ASM_ARCH_GPIO_H_
 
+#include <linux/kernel.h>
+
 #define KS8695_GPIO_0		0
 #define KS8695_GPIO_1		1
 #define KS8695_GPIO_2		2
@@ -74,6 +76,7 @@ static inline int gpio_request(unsigned int pin, const char *label)
 
 static inline void gpio_free(unsigned int pin)
 {
+	might_sleep();
 }
 
 #endif
diff --git a/arch/arm/mach-ns9xxx/gpio.c b/arch/arm/mach-ns9xxx/gpio.c
index 5241e6a286c..5503ca09c4a 100644
--- a/arch/arm/mach-ns9xxx/gpio.c
+++ b/arch/arm/mach-ns9xxx/gpio.c
@@ -8,6 +8,7 @@
  * under the terms of the GNU General Public License version 2 as published by
  * the Free Software Foundation.
  */
+#include <linux/kernel.h>
 #include <linux/compiler.h>
 #include <linux/init.h>
 #include <linux/spinlock.h>
@@ -63,6 +64,7 @@ EXPORT_SYMBOL(gpio_request);
 
 void gpio_free(unsigned gpio)
 {
+	might_sleep();
 	clear_bit(gpio, gpiores);
 	return;
 }
diff --git a/arch/arm/mach-orion5x/gpio.c b/arch/arm/mach-orion5x/gpio.c
index fc419868e39..f99d08811e5 100644
--- a/arch/arm/mach-orion5x/gpio.c
+++ b/arch/arm/mach-orion5x/gpio.c
@@ -165,6 +165,8 @@ EXPORT_SYMBOL(gpio_request);
 
 void gpio_free(unsigned pin)
 {
+	might_sleep();
+
 	if (pin >= GPIO_MAX || !test_bit(pin, gpio_valid)) {
 		pr_debug("%s: invalid GPIO %d\n", __func__, pin);
 		return;