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 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 #if IS_ENABLED(CONFIG_LEDS_CLASS_FLASH) 89 /** 90 * led_classdev_flash_register_ext - register a new object of LED class with 91 * init data and with support for flash LEDs 92 * @parent: LED flash controller device this flash LED is driven by 93 * @fled_cdev: the led_classdev_flash structure for this device 94 * @init_data: the LED class flash device initialization data 95 * 96 * Returns: 0 on success or negative error value on failure 97 */ 98 int led_classdev_flash_register_ext(struct device *parent, 99 struct led_classdev_flash *fled_cdev, 100 struct led_init_data *init_data); 101 102 /** 103 * led_classdev_flash_unregister - unregisters an object of led_classdev class 104 * with support for flash LEDs 105 * @fled_cdev: the flash LED to unregister 106 * 107 * Unregister a previously registered via led_classdev_flash_register object 108 */ 109 void led_classdev_flash_unregister(struct led_classdev_flash *fled_cdev); 110 111 int devm_led_classdev_flash_register_ext(struct device *parent, 112 struct led_classdev_flash *fled_cdev, 113 struct led_init_data *init_data); 114 115 116 void devm_led_classdev_flash_unregister(struct device *parent, 117 struct led_classdev_flash *fled_cdev); 118 119 #else 120 121 static inline int led_classdev_flash_register_ext(struct device *parent, 122 struct led_classdev_flash *fled_cdev, 123 struct led_init_data *init_data) 124 { 125 return 0; 126 } 127 128 static inline void led_classdev_flash_unregister(struct led_classdev_flash *fled_cdev) {}; 129 static inline int devm_led_classdev_flash_register_ext(struct device *parent, 130 struct led_classdev_flash *fled_cdev, 131 struct led_init_data *init_data) 132 { 133 return 0; 134 } 135 136 static inline void devm_led_classdev_flash_unregister(struct device *parent, 137 struct led_classdev_flash *fled_cdev) 138 {}; 139 140 #endif /* IS_ENABLED(CONFIG_LEDS_CLASS_FLASH) */ 141 142 static inline int led_classdev_flash_register(struct device *parent, 143 struct led_classdev_flash *fled_cdev) 144 { 145 return led_classdev_flash_register_ext(parent, fled_cdev, NULL); 146 } 147 148 static inline int devm_led_classdev_flash_register(struct device *parent, 149 struct led_classdev_flash *fled_cdev) 150 { 151 return devm_led_classdev_flash_register_ext(parent, fled_cdev, NULL); 152 } 153 154 /** 155 * led_set_flash_strobe - setup flash strobe 156 * @fled_cdev: the flash LED to set strobe on 157 * @state: 1 - strobe flash, 0 - stop flash strobe 158 * 159 * Strobe the flash LED. 160 * 161 * Returns: 0 on success or negative error value on failure 162 */ 163 static inline int led_set_flash_strobe(struct led_classdev_flash *fled_cdev, 164 bool state) 165 { 166 if (!fled_cdev) 167 return -EINVAL; 168 return fled_cdev->ops->strobe_set(fled_cdev, state); 169 } 170 171 /** 172 * led_get_flash_strobe - get flash strobe status 173 * @fled_cdev: the flash LED to query 174 * @state: 1 - flash is strobing, 0 - flash is off 175 * 176 * Check whether the flash is strobing at the moment. 177 * 178 * Returns: 0 on success or negative error value on failure 179 */ 180 static inline int led_get_flash_strobe(struct led_classdev_flash *fled_cdev, 181 bool *state) 182 { 183 if (!fled_cdev) 184 return -EINVAL; 185 if (fled_cdev->ops->strobe_get) 186 return fled_cdev->ops->strobe_get(fled_cdev, state); 187 188 return -EINVAL; 189 } 190 191 /** 192 * led_set_flash_brightness - set flash LED brightness 193 * @fled_cdev: the flash LED to set 194 * @brightness: the brightness to set it to 195 * 196 * Set a flash LED's brightness. 197 * 198 * Returns: 0 on success or negative error value on failure 199 */ 200 int led_set_flash_brightness(struct led_classdev_flash *fled_cdev, 201 u32 brightness); 202 203 /** 204 * led_update_flash_brightness - update flash LED brightness 205 * @fled_cdev: the flash LED to query 206 * 207 * Get a flash LED's current brightness and update led_flash->brightness 208 * member with the obtained value. 209 * 210 * Returns: 0 on success or negative error value on failure 211 */ 212 int led_update_flash_brightness(struct led_classdev_flash *fled_cdev); 213 214 /** 215 * led_set_flash_timeout - set flash LED timeout 216 * @fled_cdev: the flash LED to set 217 * @timeout: the flash timeout to set it to 218 * 219 * Set the flash strobe duration. 220 * 221 * Returns: 0 on success or negative error value on failure 222 */ 223 int led_set_flash_timeout(struct led_classdev_flash *fled_cdev, u32 timeout); 224 225 /** 226 * led_get_flash_fault - get the flash LED fault 227 * @fled_cdev: the flash LED to query 228 * @fault: bitmask containing flash faults 229 * 230 * Get the flash LED fault. 231 * 232 * Returns: 0 on success or negative error value on failure 233 */ 234 int led_get_flash_fault(struct led_classdev_flash *fled_cdev, u32 *fault); 235 236 #endif /* __LINUX_FLASH_LEDS_H_INCLUDED */ 237