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kernel/linux-rt-4.4.41/drivers/gpio/gpiolib-legacy.c 2.4 KB
5113f6f70   김현기   kernel add
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  #include <linux/gpio/consumer.h>
  #include <linux/gpio/driver.h>
  
  #include <linux/gpio.h>
  
  #include "gpiolib.h"
  
  void gpio_free(unsigned gpio)
  {
  	gpiod_free(gpio_to_desc(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)
  {
  	struct gpio_desc *desc;
  	int err;
  
  	desc = gpio_to_desc(gpio);
  
  	/* Compatibility: assume unavailable "valid" GPIOs will appear later */
  	if (!desc && gpio_is_valid(gpio))
  		return -EPROBE_DEFER;
  
  	err = gpiod_request(desc, label);
  	if (err)
  		return err;
  
  	if (flags & GPIOF_OPEN_DRAIN)
  		set_bit(FLAG_OPEN_DRAIN, &desc->flags);
  
  	if (flags & GPIOF_OPEN_SOURCE)
  		set_bit(FLAG_OPEN_SOURCE, &desc->flags);
  
  	if (flags & GPIOF_ACTIVE_LOW)
  		set_bit(FLAG_ACTIVE_LOW, &desc->flags);
  
  	if (flags & GPIOF_DIR_IN)
  		err = gpiod_direction_input(desc);
  	else
  		err = gpiod_direction_output_raw(desc,
  				(flags & GPIOF_INIT_HIGH) ? 1 : 0);
  
  	if (err)
  		goto free_gpio;
  
  	if (flags & GPIOF_EXPORT) {
  		err = gpiod_export(desc, flags & GPIOF_EXPORT_CHANGEABLE);
  		if (err)
  			goto free_gpio;
  	}
  
  	return 0;
  
   free_gpio:
  	gpiod_free(desc);
  	return err;
  }
  EXPORT_SYMBOL_GPL(gpio_request_one);
  
  int gpio_request(unsigned gpio, const char *label)
  {
  	struct gpio_desc *desc = gpio_to_desc(gpio);
  
  	/* Compatibility: assume unavailable "valid" GPIOs will appear later */
  	if (!desc && gpio_is_valid(gpio))
  		return -EPROBE_DEFER;
  
  	return gpiod_request(desc, label);
  }
  EXPORT_SYMBOL_GPL(gpio_request);
  
  /**
   * 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(const 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(const struct gpio *array, size_t num)
  {
  	while (num--)
  		gpio_free((array++)->gpio);
  }
  EXPORT_SYMBOL_GPL(gpio_free_array);