diff options
Diffstat (limited to 'drivers/gpio/gpiolib.c')
-rw-r--r-- | drivers/gpio/gpiolib.c | 67 |
1 files changed, 65 insertions, 2 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 350842ad3632..76be229c814d 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -9,6 +9,7 @@ #include <linux/seq_file.h> #include <linux/gpio.h> #include <linux/idr.h> +#include <linux/slab.h> /* Optional implementation infrastructure for GPIO interfaces. @@ -623,7 +624,9 @@ static const struct attribute_group gpiochip_attr_group = { * /sys/class/gpio/unexport ... write-only * integer N ... number of GPIO to unexport */ -static ssize_t export_store(struct class *class, const char *buf, size_t len) +static ssize_t export_store(struct class *class, + struct class_attribute *attr, + const char *buf, size_t len) { long gpio; int status; @@ -653,7 +656,9 @@ done: return status ? : len; } -static ssize_t unexport_store(struct class *class, const char *buf, size_t len) +static ssize_t unexport_store(struct class *class, + struct class_attribute *attr, + const char *buf, size_t len) { long gpio; int status; @@ -1237,6 +1242,64 @@ void gpio_free(unsigned gpio) } EXPORT_SYMBOL_GPL(gpio_free); +/** + * gpio_request_one - request a single GPIO with initial configuration + * @gpio: the GPIO number + * @flags: GPIO configuration as specified by GPIOF_* + * @label: a literal description string of this GPIO + */ +int gpio_request_one(unsigned gpio, unsigned long flags, const char *label) +{ + int err; + + err = gpio_request(gpio, label); + if (err) + return err; + + if (flags & GPIOF_DIR_IN) + err = gpio_direction_input(gpio); + else + err = gpio_direction_output(gpio, + (flags & GPIOF_INIT_HIGH) ? 1 : 0); + + return err; +} +EXPORT_SYMBOL_GPL(gpio_request_one); + +/** + * gpio_request_array - request multiple GPIOs in a single call + * @array: array of the 'struct gpio' + * @num: how many GPIOs in the array + */ +int gpio_request_array(struct gpio *array, size_t num) +{ + int i, err; + + for (i = 0; i < num; i++, array++) { + err = gpio_request_one(array->gpio, array->flags, array->label); + if (err) + goto err_free; + } + return 0; + +err_free: + while (i--) + gpio_free((--array)->gpio); + return err; +} +EXPORT_SYMBOL_GPL(gpio_request_array); + +/** + * gpio_free_array - release multiple GPIOs in a single call + * @array: array of the 'struct gpio' + * @num: how many GPIOs in the array + */ +void gpio_free_array(struct gpio *array, size_t num) +{ + while (num--) + gpio_free((array++)->gpio); +} +EXPORT_SYMBOL_GPL(gpio_free_array); /** * gpiochip_is_requested - return string iff signal was requested |