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 
lcdev_to_flcdev(struct led_classdev * lcdev)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 
led_classdev_flash_register_ext(struct device * parent,struct led_classdev_flash * fled_cdev,struct led_init_data * init_data)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 
led_classdev_flash_unregister(struct led_classdev_flash * fled_cdev)128 static inline void led_classdev_flash_unregister(struct led_classdev_flash *fled_cdev) {};
devm_led_classdev_flash_register_ext(struct device * parent,struct led_classdev_flash * fled_cdev,struct led_init_data * init_data)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 
devm_led_classdev_flash_unregister(struct device * parent,struct led_classdev_flash * fled_cdev)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 
led_classdev_flash_register(struct device * parent,struct led_classdev_flash * fled_cdev)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 
devm_led_classdev_flash_register(struct device * parent,struct led_classdev_flash * fled_cdev)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  */
led_set_flash_strobe(struct led_classdev_flash * fled_cdev,bool state)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  */
led_get_flash_strobe(struct led_classdev_flash * fled_cdev,bool * state)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