Commit 370232d0 authored by Bartosz Golaszewski's avatar Bartosz Golaszewski
Browse files

gpiolib: provide gpiod_to_gpio_device() 



Accessing struct gpio_chip backing a GPIO device is only allowed for the
actual providers of that chip.

Similarly to how we introduced gpio_device_find() in order to replace
the abused gpiochip_find(), let's introduce a counterpart to
gpiod_to_chip() that returns a reference to the GPIO device owning the
descriptor. This is done in order to later remove gpiod_to_chip()
entirely.

Signed-off-by: default avatarBartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: default avatarPeter Rosin <peda@axentia.se>
Acked-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent 1559d149

drivers/gpio/gpiolib.c

+21 −0
Original line number Diff line number Diff line
@@ -220,6 +220,27 @@ struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) 
}

EXPORT_SYMBOL_GPL(gpiod_to_chip);



/**

 * gpiod_to_gpio_device() - Return the GPIO device to which this descriptor

 *                          belongs.

 * @desc: Descriptor for which to return the GPIO device.

 *

 * This *DOES NOT* increase the reference count of the GPIO device as it's

 * expected that the descriptor is requested and the users already holds a

 * reference to the device.

 *

 * Returns:

 * Address of the GPIO device owning this descriptor.

 */

struct gpio_device *gpiod_to_gpio_device(struct gpio_desc *desc)

{

	if (!desc)

		return NULL;



	return desc->gdev;

}

EXPORT_SYMBOL_GPL(gpiod_to_gpio_device);



/**

 * gpio_device_get_chip() - Get the gpio_chip implementation of this GPIO device

 * @gdev: GPIO device

include/linux/gpio/driver.h

+1 −0
Original line number Diff line number Diff line
@@ -785,6 +785,7 @@ int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset); 
void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset);



struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc);

struct gpio_device *gpiod_to_gpio_device(struct gpio_desc *desc);



#else /* CONFIG_GPIOLIB */