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        if (!fled_cdev)
 125                return -EINVAL;
 126        return fled_cdev->ops->strobe_set(fled_cdev, state);
 127}
 128
 129/**
 130 * led_get_flash_strobe - get flash strobe status
 131 * @fled_cdev: the flash LED to query
 132 * @state: 1 - flash is strobing, 0 - flash is off
 133 *
 134 * Check whether the flash is strobing at the moment.
 135 *
 136 * Returns: 0 on success or negative error value on failure
 137 */
 138static inline int led_get_flash_strobe(struct led_classdev_flash *fled_cdev,
 139                                        bool *state)
 140{
 141        if (!fled_cdev)
 142                return -EINVAL;
 143        if (fled_cdev->ops->strobe_get)
 144                return fled_cdev->ops->strobe_get(fled_cdev, state);
 145
 146        return -EINVAL;
 147}
 148
 149/**
 150 * led_set_flash_brightness - set flash LED brightness
 151 * @fled_cdev: the flash LED to set
 152 * @brightness: the brightness to set it to
 153 *
 154 * Set a flash LED's brightness.
 155 *
 156 * Returns: 0 on success or negative error value on failure
 157 */
 158extern int led_set_flash_brightness(struct led_classdev_flash *fled_cdev,
 159                                        u32 brightness);
 160
 161/**
 162 * led_update_flash_brightness - update flash LED brightness
 163 * @fled_cdev: the flash LED to query
 164 *
 165 * Get a flash LED's current brightness and update led_flash->brightness
 166 * member with the obtained value.
 167 *
 168 * Returns: 0 on success or negative error value on failure
 169 */
 170extern int led_update_flash_brightness(struct led_classdev_flash *fled_cdev);
 171
 172/**
 173 * led_set_flash_timeout - set flash LED timeout
 174 * @fled_cdev: the flash LED to set
 175 * @timeout: the flash timeout to set it to
 176 *
 177 * Set the flash strobe duration.
 178 *
 179 * Returns: 0 on success or negative error value on failure
 180 */
 181extern int led_set_flash_timeout(struct led_classdev_flash *fled_cdev,
 182                                        u32 timeout);
 183
 184/**
 185 * led_get_flash_fault - get the flash LED fault
 186 * @fled_cdev: the flash LED to query
 187 * @fault: bitmask containing flash faults
 188 *
 189 * Get the flash LED fault.
 190 *
 191 * Returns: 0 on success or negative error value on failure
 192 */
 193extern int led_get_flash_fault(struct led_classdev_flash *fled_cdev,
 194                                        u32 *fault);
 195
 196#endif  /* __LINUX_FLASH_LEDS_H_INCLUDED */
 197