Commit ee25fba7 authored by Bartosz Golaszewski's avatar Bartosz Golaszewski
Browse files

gpiolib: provide gpiochip_dup_line_label() 



gpiochip_is_requested() not only has a misleading name but it returns
a pointer to a string that is freed when the descriptor is released.

Provide a new helper meant to replace it, which returns a copy of the
label string instead.

Signed-off-by: default avatarBartosz Golaszewski <bartosz.golaszewski@linaro.org>
Acked-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent b85ea95d

drivers/gpio/gpiolib.c

+29 −0
Original line number Diff line number Diff line
@@ -2386,6 +2386,35 @@ const char *gpiochip_is_requested(struct gpio_chip *gc, unsigned int offset) 
}

EXPORT_SYMBOL_GPL(gpiochip_is_requested);



/**

 * gpiochip_dup_line_label - Get a copy of the consumer label.

 * @gc: GPIO chip controlling this line.

 * @offset: Hardware offset of the line.

 *

 * Returns:

 * Pointer to a copy of the consumer label if the line is requested or NULL

 * if it's not. If a valid pointer was returned, it must be freed using

 * kfree(). In case of a memory allocation error, the function returns %ENOMEM.

 *

 * Must not be called from atomic context.

 */

char *gpiochip_dup_line_label(struct gpio_chip *gc, unsigned int offset)

{

	const char *label;

	char *copy;



	label = gpiochip_is_requested(gc, offset);

	if (!label)

		return NULL;



	copy = kstrdup(label, GFP_KERNEL);

	if (!copy)

		return ERR_PTR(-ENOMEM);



	return copy;

}

EXPORT_SYMBOL_GPL(gpiochip_dup_line_label);



/**

 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor

 * @gc: GPIO chip

include/linux/gpio/driver.h

+1 −0
Original line number Diff line number Diff line
@@ -532,6 +532,7 @@ struct gpio_chip { 
};



const char *gpiochip_is_requested(struct gpio_chip *gc, unsigned int offset);

char *gpiochip_dup_line_label(struct gpio_chip *gc, unsigned int offset);



/**

 * for_each_requested_gpio_in_range - iterates over requested GPIOs in a given range