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

   1/* SPDX-License-Identifier: GPL-2.0-only */
   2/*
   3 * LED Flash class interface
   4 *
   5 * Copyright (C) 2015 Samsung Electronics Co., Ltd.
   6 * Author: Jacek Anaszewski <j.anaszewski@samsung.com>
   7 */
   8#ifndef __LINUX_FLASH_LEDS_H_INCLUDED
   9#define __LINUX_FLASH_LEDS_H_INCLUDED
  10
  11#include <linux/leds.h>
  12
  13struct device_node;
  14struct led_classdev_flash;
  15
  16/*
  17 * Supported led fault bits - must be kept in synch
  18 * with V4L2_FLASH_FAULT bits.
  19 */
  20#define LED_FAULT_OVER_VOLTAGE          (1 << 0)
  21#define LED_FAULT_TIMEOUT               (1 << 1)
  22#define LED_FAULT_OVER_TEMPERATURE      (1 << 2)
  23#define LED_FAULT_SHORT_CIRCUIT         (1 << 3)
  24#define LED_FAULT_OVER_CURRENT          (1 << 4)
  25#define LED_FAULT_INDICATOR             (1 << 5)
  26#define LED_FAULT_UNDER_VOLTAGE         (1 << 6)
  27#define LED_FAULT_INPUT_VOLTAGE         (1 << 7)
  28#define LED_FAULT_LED_OVER_TEMPERATURE  (1 << 8)
  29#define LED_NUM_FLASH_FAULTS            9
  30
  31#define LED_FLASH_SYSFS_GROUPS_SIZE     5
  32
  33struct led_flash_ops {
  34        /* set flash brightness */
  35        int (*flash_brightness_set)(struct led_classdev_flash *fled_cdev,
  36                                        u32 brightness);
  37        /* get flash brightness */
  38        int (*flash_brightness_get)(struct led_classdev_flash *fled_cdev,
  39                                        u32 *brightness);
  40        /* set flash strobe state */
  41        int (*strobe_set)(struct led_classdev_flash *fled_cdev, bool state);
  42        /* get flash strobe state */
  43        int (*strobe_get)(struct led_classdev_flash *fled_cdev, bool *state);
  44        /* set flash timeout */
  45        int (*timeout_set)(struct led_classdev_flash *fled_cdev, u32 timeout);
  46        /* get the flash LED fault */
  47        int (*fault_get)(struct led_classdev_flash *fled_cdev, u32 *fault);
  48};
  49
  50/*
  51 * Current value of a flash setting along
  52 * with its constraints.
  53 */
  54struct led_flash_setting {
  55        /* maximum allowed value */
  56        u32 min;
  57        /* maximum allowed value */
  58        u32 max;
  59        /* step value */
  60        u32 step;
  61        /* current value */
  62        u32 val;
  63};
  64
  65struct led_classdev_flash {
  66        /* led class device */
  67        struct led_classdev led_cdev;
  68
  69        /* flash led specific ops */
  70        const struct led_flash_ops *ops;
  71
  72        /* flash brightness value in microamperes along with its constraints */
  73        struct led_flash_setting brightness;
  74
  75        /* flash timeout value in microseconds along with its constraints */
  76        struct led_flash_setting timeout;
  77
  78        /* LED Flash class sysfs groups */
  79        const struct attribute_group *sysfs_groups[LED_FLASH_SYSFS_GROUPS_SIZE];
  80};
  81
  82static inline struct led_classdev_flash *lcdev_to_flcdev(
  83                                                struct led_classdev *lcdev)
  84{
  85        return container_of(lcdev, struct led_classdev_flash, led_cdev);
  86}
  87
  88/**
  89 * led_classdev_flash_register - register a new object of led_classdev class
  90 *                               with support for flash LEDs
  91 * @parent: the flash LED to register
  92 * @fled_cdev: the led_classdev_flash structure for this device
  93 *
  94 * Returns: 0 on success or negative error value on failure
  95 */
  96extern int led_classdev_flash_register(struct device *parent,
  97                                struct led_classdev_flash *fled_cdev);
  98
  99/**
 100 * led_classdev_flash_unregister - unregisters an object of led_classdev class
 101 *                                 with support for flash LEDs
 102 * @fled_cdev: the flash LED to unregister
 103 *
 104 * Unregister a previously registered via led_classdev_flash_register object
 105 */
 106extern void led_classdev_flash_unregister(struct led_classdev_flash *fled_cdev);
 107
 108/**
 109 * led_set_flash_strobe - setup flash strobe
 110 * @fled_cdev: the flash LED to set strobe on
 111 * @state: 1 - strobe flash, 0 - stop flash strobe
 112 *
 113 * Strobe the flash LED.
 114 *
 115 * Returns: 0 on success or negative error value on failure
 116 */
 117static inline int led_set_flash_strobe(struct led_classdev_flash *fled_cdev,
 118                                        bool state)
 119{
 120        if (!fled_cdev)
 121                return -EINVAL;
 122        return fled_cdev->ops->strobe_set(fled_cdev, state);
 123}
 124
 125/**
 126 * led_get_flash_strobe - get flash strobe status
 127 * @fled_cdev: the flash LED to query
 128 * @state: 1 - flash is strobing, 0 - flash is off
 129 *
 130 * Check whether the flash is strobing at the moment.
 131 *
 132 * Returns: 0 on success or negative error value on failure
 133 */
 134static inline int led_get_flash_strobe(struct led_classdev_flash *fled_cdev,
 135                                        bool *state)
 136{
 137        if (!fled_cdev)
 138                return -EINVAL;
 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