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 <[email protected]> 7 */ 8 #ifndef __LINUX_FLASH_LEDS_H_INCLUDED 9 #define __LINUX_FLASH_LEDS_H_INCLUDED 10 11 #include <linux/leds.h> 12 13 struct device_node; 14 struct 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 33 struct 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 */ 54 struct 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 65 struct 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 82 static 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_ext - register a new object of LED class with 90 * init data and with support for flash LEDs 91 * @parent: LED flash controller device this flash LED is driven by 92 * @fled_cdev: the led_classdev_flash structure for this device 93 * @init_data: the LED class flash device initialization data 94 * 95 * Returns: 0 on success or negative error value on failure 96 */ 97 extern int led_classdev_flash_register_ext(struct device *parent, 98 struct led_classdev_flash *fled_cdev, 99 struct led_init_data *init_data); 100 101 static inline int led_classdev_flash_register(struct device *parent, 102 struct led_classdev_flash *fled_cdev) 103 { 104 return led_classdev_flash_register_ext(parent, fled_cdev, NULL); 105 } 106 107 /** 108 * led_classdev_flash_unregister - unregisters an object of led_classdev class 109 * with support for flash LEDs 110 * @fled_cdev: the flash LED to unregister 111 * 112 * Unregister a previously registered via led_classdev_flash_register object 113 */ 114 extern void led_classdev_flash_unregister(struct led_classdev_flash *fled_cdev); 115 116 /** 117 * led_set_flash_strobe - setup flash strobe 118 * @fled_cdev: the flash LED to set strobe on 119 * @state: 1 - strobe flash, 0 - stop flash strobe 120 * 121 * Strobe the flash LED. 122 * 123 * Returns: 0 on success or negative error value on failure 124 */ 125 static inline int led_set_flash_strobe(struct led_classdev_flash *fled_cdev, 126 bool state) 127 { 128 if (!fled_cdev) 129 return -EINVAL; 130 return fled_cdev->ops->strobe_set(fled_cdev, state); 131 } 132 133 /** 134 * led_get_flash_strobe - get flash strobe status 135 * @fled_cdev: the flash LED to query 136 * @state: 1 - flash is strobing, 0 - flash is off 137 * 138 * Check whether the flash is strobing at the moment. 139 * 140 * Returns: 0 on success or negative error value on failure 141 */ 142 static inline int led_get_flash_strobe(struct led_classdev_flash *fled_cdev, 143 bool *state) 144 { 145 if (!fled_cdev) 146 return -EINVAL; 147 if (fled_cdev->ops->strobe_get) 148 return fled_cdev->ops->strobe_get(fled_cdev, state); 149 150 return -EINVAL; 151 } 152 153 /** 154 * led_set_flash_brightness - set flash LED brightness 155 * @fled_cdev: the flash LED to set 156 * @brightness: the brightness to set it to 157 * 158 * Set a flash LED's brightness. 159 * 160 * Returns: 0 on success or negative error value on failure 161 */ 162 extern int led_set_flash_brightness(struct led_classdev_flash *fled_cdev, 163 u32 brightness); 164 165 /** 166 * led_update_flash_brightness - update flash LED brightness 167 * @fled_cdev: the flash LED to query 168 * 169 * Get a flash LED's current brightness and update led_flash->brightness 170 * member with the obtained value. 171 * 172 * Returns: 0 on success or negative error value on failure 173 */ 174 extern int led_update_flash_brightness(struct led_classdev_flash *fled_cdev); 175 176 /** 177 * led_set_flash_timeout - set flash LED timeout 178 * @fled_cdev: the flash LED to set 179 * @timeout: the flash timeout to set it to 180 * 181 * Set the flash strobe duration. 182 * 183 * Returns: 0 on success or negative error value on failure 184 */ 185 extern int led_set_flash_timeout(struct led_classdev_flash *fled_cdev, 186 u32 timeout); 187 188 /** 189 * led_get_flash_fault - get the flash LED fault 190 * @fled_cdev: the flash LED to query 191 * @fault: bitmask containing flash faults 192 * 193 * Get the flash LED fault. 194 * 195 * Returns: 0 on success or negative error value on failure 196 */ 197 extern int led_get_flash_fault(struct led_classdev_flash *fled_cdev, 198 u32 *fault); 199 200 #endif /* __LINUX_FLASH_LEDS_H_INCLUDED */ 201