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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 */