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gpio: drop lock before reading GPIO direction

When adding the gpiochip, the GPIO HW drivers' callback get_direction()
could get called in atomic context. Some of the GPIO HW drivers may
sleep when accessing the register.

Move the lock before initializing the descriptors.

Reported-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Linus Walleij 9 years ago
parent
commit
545ebd9a9b
1 changed files with 2 additions and 2 deletions
  1. 2 2
      drivers/gpio/gpiolib.c

+ 2 - 2
drivers/gpio/gpiolib.c

@@ -629,6 +629,8 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data)
 		goto err_free_label;
 	}
 
+	spin_unlock_irqrestore(&gpio_lock, flags);
+
 	for (i = 0; i < chip->ngpio; i++) {
 		struct gpio_desc *desc = &gdev->descs[i];
 
@@ -660,8 +662,6 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data)
 		}
 	}
 
-	spin_unlock_irqrestore(&gpio_lock, flags);
-
 #ifdef CONFIG_PINCTRL
 	INIT_LIST_HEAD(&gdev->pin_ranges);
 #endif