text: /*
   * Copyright (c) 2018 Linaro Limited
   *
   * SPDX-License-Identifier: Apache-2.0
   */
  
  /**
   * @file
   * @brief Public LED driver APIs
   */
  
  #ifndef ZEPHYR_INCLUDE_DRIVERS_LED_H_
  #define ZEPHYR_INCLUDE_DRIVERS_LED_H_
  
  /**
   * @brief LED Interface
   * @defgroup led_interface LED Interface
   * @ingroup io_interfaces
   * @{
   */
  
  #include <zephyr/types.h>
  #include <device.h>
  
  /**
   * @typedef led_api_blink()
   * @brief Callback API for blinking an LED
   *
   * @see led_blink() for argument descriptions.
   */
  typedef int (*led_api_blink)(struct device *dev, uint32_t led,
  			     uint32_t delay_on, uint32_t delay_off);
  
  /**
   * @typedef led_api_set_brightness()
   * @brief Callback API for setting brightness of an LED
   *
   * @see led_set_brightness() for argument descriptions.
   */
  typedef int (*led_api_set_brightness)(struct device *dev, uint32_t led,
  				      uint8_t value);
  /**
   * @typedef led_api_on()
   * @brief Callback API for turning on an LED
   *
   * @see led_on() for argument descriptions.
   */
  typedef int (*led_api_on)(struct device *dev, uint32_t led);
  
  /**
   * @typedef led_api_off()
   * @brief Callback API for turning off an LED
   *
   * @see led_off() for argument descriptions.
   */
  typedef int (*led_api_off)(struct device *dev, uint32_t led);
  
  /**
   * @brief LED driver API
   *
   * This is the mandatory API any LED driver needs to expose.
   */
  __subsystem struct led_driver_api {
  	led_api_blink blink;
  	led_api_set_brightness set_brightness;
  	led_api_on on;
  	led_api_off off;
  };
  
  /**
   * @brief Blink an LED
   *
   * This routine starts blinking an LED forever with the given time period
   *
   * @param dev LED device
   * @param led LED channel/pin
   * @param delay_on Time period (in milliseconds) an LED should be ON
   * @param delay_off Time period (in milliseconds) an LED should be OFF
   * @return 0 on success, negative on error
   */
  __syscall int led_blink(struct device *dev, uint32_t led,
  			    uint32_t delay_on, uint32_t delay_off);
  
  static inline int z_impl_led_blink(struct device *dev, uint32_t led,
  			    uint32_t delay_on, uint32_t delay_off)
  {
  	const struct led_driver_api *api =
  		(const struct led_driver_api *)dev->driver_api;
  
  	return api->blink(dev, led, delay_on, delay_off);
  }
  
  /**
   * @brief Set LED brightness
   *
   * This routine sets the brightness of a LED to the given value.
   * Calling this function after led_blink() won't affect blinking.
   *
   * @param dev LED device
   * @param led LED channel/pin
   * @param value Brightness value to set in percent
   * @return 0 on success, negative on error
   */
  __syscall int led_set_brightness(struct device *dev, uint32_t led,
  				     uint8_t value);
  
  static inline int z_impl_led_set_brightness(struct device *dev, uint32_t led,
  				     uint8_t value)
  {
  	const struct led_driver_api *api =
  		(const struct led_driver_api *)dev->driver_api;
  
  	return api->set_brightness(dev, led, value);
  }
  
  /**
   * @brief Turn on an LED
   *
   * This routine turns on an LED
   *
   * @param dev LED device
   * @param led LED channel/pin
   * @return 0 on success, negative on error
   */
  __syscall int led_on(struct device *dev, uint32_t led);
  
  static inline int z_impl_led_on(struct device *dev, uint32_t led)
  {
  	const struct led_driver_api *api =
  		(const struct led_driver_api *)dev->driver_api;
  
  	return api->on(dev, led);
  }
  
  /**
   * @brief Turn off an LED
   *
   * This routine turns off an LED
   *
   * @param dev LED device
   * @param led LED channel/pin
   * @return 0 on success, negative on error
   */
  __syscall int led_off(struct device *dev, uint32_t led);
  
  static inline int z_impl_led_off(struct device *dev, uint32_t led)
  {
  	const struct led_driver_api *api =
  		(const struct led_driver_api *)dev->driver_api;
  
  	return api->off(dev, led);
  }
  
  /**
   * @}
   */
  
  #include <syscalls/led.h>
  
  #endif	/* ZEPHYR_INCLUDE_DRIVERS_LED_H_ */
  