LXR linux/include/linux/led-class-flash.h

   1/*
   2 * LED Flash class interface
   3 *
   4 * Copyright (C) 2015 Samsung Electronics Co., Ltd.
   5 * Author: Jacek Anaszewski <j.anaszewski@samsung.com>
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License version 2 as
   9 * published by the Free Software Foundation.
  10 *
  11 */
  12#ifndef __LINUX_FLASH_LEDS_H_INCLUDED
  13#define __LINUX_FLASH_LEDS_H_INCLUDED
  14
  15#include <linux/leds.h>
  16
  17struct device_node;
  18struct led_classdev_flash;
  19
  20/*
  21 * Supported led fault bits - must be kept in synch
  22 * with V4L2_FLASH_FAULT bits.
  23 */
  24#define LED_FAULT_OVER_VOLTAGE          (1 << 0)
  25#define LED_FAULT_TIMEOUT               (1 << 1)
  26#define LED_FAULT_OVER_TEMPERATURE      (1 << 2)
  27#define LED_FAULT_SHORT_CIRCUIT         (1 << 3)
  28#define LED_FAULT_OVER_CURRENT          (1 << 4)
  29#define LED_FAULT_INDICATOR             (1 << 5)
  30#define LED_FAULT_UNDER_VOLTAGE         (1 << 6)
  31#define LED_FAULT_INPUT_VOLTAGE         (1 << 7)
  32#define LED_FAULT_LED_OVER_TEMPERATURE  (1 << 8)
  33#define LED_NUM_FLASH_FAULTS            9
  34
  35#define LED_FLASH_SYSFS_GROUPS_SIZE     5
  36
  37struct led_flash_ops {
  38        /* set flash brightness */
  39        int (*flash_brightness_set)(struct led_classdev_flash *fled_cdev,
  40                                        u32 brightness);
  41        /* get flash brightness */
  42        int (*flash_brightness_get)(struct led_classdev_flash *fled_cdev,
  43                                        u32 *brightness);
  44        /* set flash strobe state */
  45        int (*strobe_set)(struct led_classdev_flash *fled_cdev, bool state);
  46        /* get flash strobe state */
  47        int (*strobe_get)(struct led_classdev_flash *fled_cdev, bool *state);
  48        /* set flash timeout */
  49        int (*timeout_set)(struct led_classdev_flash *fled_cdev, u32 timeout);
  50        /* get the flash LED fault */
  51        int (*fault_get)(struct led_classdev_flash *fled_cdev, u32 *fault);
  52};
  53
  54/*
  55 * Current value of a flash setting along
  56 * with its constraints.
  57 */
  58struct led_flash_setting {
  59        /* maximum allowed value */
  60        u32 min;
  61        /* maximum allowed value */
  62        u32 max;
  63        /* step value */
  64        u32 step;
  65        /* current value */
  66        u32 val;
  67};
  68
  69struct led_classdev_flash {
  70        /* led class device */
  71        struct led_classdev led_cdev;
  72
  73        /* flash led specific ops */
  74        const struct led_flash_ops *ops;
  75
  76        /* flash brightness value in microamperes along with its constraints */
  77        struct led_flash_setting brightness;
  78
  79        /* flash timeout value in microseconds along with its constraints */
  80        struct led_flash_setting timeout;
  81
  82        /* LED Flash class sysfs groups */
  83        const struct attribute_group *sysfs_groups[LED_FLASH_SYSFS_GROUPS_SIZE];
  84};
  85
  86static inline struct led_classdev_flash *lcdev_to_flcdev(
  87                                                struct led_classdev *lcdev)
  88{
  89        return container_of(lcdev, struct led_classdev_flash, led_cdev);
  90}
  91
  92/**
  93 * led_classdev_flash_register - register a new object of led_classdev class
  94 *                               with support for flash LEDs
  95 * @parent: the flash LED to register
  96 * @fled_cdev: the led_classdev_flash structure for this device
  97 *
  98 * Returns: 0 on success or negative error value on failure
  99 */
 100extern int led_classdev_flash_register(struct device *parent,
 101                                struct led_classdev_flash *fled_cdev);
 102
 103/**
 104 * led_classdev_flash_unregister - unregisters an object of led_classdev class
 105 *                                 with support for flash LEDs
 106 * @fled_cdev: the flash LED to unregister
 107 *
 108 * Unregister a previously registered via led_classdev_flash_register object
 109 */
 110extern void led_classdev_flash_unregister(struct led_classdev_flash *fled_cdev);
 111
 112/**
 113 * led_set_flash_strobe - setup flash strobe
 114 * @fled_cdev: the flash LED to set strobe on
 115 * @state: 1 - strobe flash, 0 - stop flash strobe
 116 *
 117 * Strobe the flash LED.
 118 *
 119 * Returns: 0 on success or negative error value on failure
 120 */
 121static inline int led_set_flash_strobe(struct led_classdev_flash *fled_cdev,
 122                                        bool state)
 123{
 124        return fled_cdev->ops->strobe_set(fled_cdev, state);
 125}
 126
 127/**
 128 * led_get_flash_strobe - get flash strobe status
 129 * @fled_cdev: the flash LED to query
 130 * @state: 1 - flash is strobing, 0 - flash is off
 131 *
 132 * Check whether the flash is strobing at the moment.
 133 *
 134 * Returns: 0 on success or negative error value on failure
 135 */
 136static inline int led_get_flash_strobe(struct led_classdev_flash *fled_cdev,
 137                                        bool *state)
 138{
 139        if (fled_cdev->ops->strobe_get)
 140                return fled_cdev->ops->strobe_get(fled_cdev, state);
 141
 142        return -EINVAL;
 143}
 144
 145/**
 146 * led_set_flash_brightness - set flash LED brightness
 147 * @fled_cdev: the flash LED to set
 148 * @brightness: the brightness to set it to
 149 *
 150 * Set a flash LED's brightness.
 151 *
 152 * Returns: 0 on success or negative error value on failure
 153 */
 154extern int led_set_flash_brightness(struct led_classdev_flash *fled_cdev,
 155                                        u32 brightness);
 156
 157/**
 158 * led_update_flash_brightness - update flash LED brightness
 159 * @fled_cdev: the flash LED to query
 160 *
 161 * Get a flash LED's current brightness and update led_flash->brightness
 162 * member with the obtained value.
 163 *
 164 * Returns: 0 on success or negative error value on failure
 165 */
 166extern int led_update_flash_brightness(struct led_classdev_flash *fled_cdev);
 167
 168/**
 169 * led_set_flash_timeout - set flash LED timeout
 170 * @fled_cdev: the flash LED to set
 171 * @timeout: the flash timeout to set it to
 172 *
 173 * Set the flash strobe duration.
 174 *
 175 * Returns: 0 on success or negative error value on failure
 176 */
 177extern int led_set_flash_timeout(struct led_classdev_flash *fled_cdev,
 178                                        u32 timeout);
 179
 180/**
 181 * led_get_flash_fault - get the flash LED fault
 182 * @fled_cdev: the flash LED to query
 183 * @fault: bitmask containing flash faults
 184 *
 185 * Get the flash LED fault.
 186 *
 187 * Returns: 0 on success or negative error value on failure
 188 */
 189extern int led_get_flash_fault(struct led_classdev_flash *fled_cdev,
 190                                        u32 *fault);
 191
 192#endif  /* __LINUX_FLASH_LEDS_H_INCLUDED */
 193