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 17 struct device_node; 18 struct 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 37 struct 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 */ 58 struct 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 69 struct 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 86 static 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 */ 100 extern 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 */ 110 extern 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 */ 121 static 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 */ 138 static 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 */ 158 extern 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 */ 170 extern 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 */ 181 extern 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 */ 193 extern int led_get_flash_fault(struct led_classdev_flash *fled_cdev, 194 u32 *fault); 195 196 #endif /* __LINUX_FLASH_LEDS_H_INCLUDED */ 197