diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index b5f472beb3bd..4c15a70d4d80 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -723,6 +723,22 @@ static int gpiochip_add_pin_ranges(struct gpio_chip *gc) return 0; } +/** + * gpiochip_query_valid_mask - return the GPIO validity information + * @gc: gpio chip which validity information is queried + * + * Returns: bitmap representing valid GPIOs or NULL if all GPIOs are valid + * + * Some GPIO chips may support configurations where some of the pins aren't + * available. These chips can have valid_mask set to represent the valid + * GPIOs. This function can be used to retrieve this information. + */ +const unsigned long *gpiochip_query_valid_mask(const struct gpio_chip *gc) +{ + return gc->valid_mask; +} +EXPORT_SYMBOL_GPL(gpiochip_query_valid_mask); + bool gpiochip_line_is_valid(const struct gpio_chip *gc, unsigned int offset) { diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index 83e0a7e86962..e3b59fda62e0 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -720,6 +720,7 @@ bool gpiochip_line_is_open_source(struct gpio_chip *gc, unsigned int offset); /* Sleep persistence inquiry for drivers */ bool gpiochip_line_is_persistent(struct gpio_chip *gc, unsigned int offset); bool gpiochip_line_is_valid(const struct gpio_chip *gc, unsigned int offset); +const unsigned long *gpiochip_query_valid_mask(const struct gpio_chip *gc); /* get driver data */ void *gpiochip_get_data(struct gpio_chip *gc);