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