1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * V4L2 flash LED sub-device registration helpers.
4 *
5 * Copyright (C) 2015 Samsung Electronics Co., Ltd
6 * Author: Jacek Anaszewski <j.anaszewski@samsung.com>
7 */
8
9 #ifndef _V4L2_FLASH_H
10 #define _V4L2_FLASH_H
11
12 #include <media/v4l2-ctrls.h>
13 #include <media/v4l2-subdev.h>
14
15 struct led_classdev_flash;
16 struct led_classdev;
17 struct v4l2_flash;
18 enum led_brightness;
19
20 /**
21 * struct v4l2_flash_ctrl_data - flash control initialization data, filled
22 * basing on the features declared by the LED flash
23 * class driver in the v4l2_flash_config
24 * @config: initialization data for a control
25 * @cid: contains v4l2 flash control id if the config
26 * field was initialized, 0 otherwise
27 */
28 struct v4l2_flash_ctrl_data {
29 struct v4l2_ctrl_config config;
30 u32 cid;
31 };
32
33 /**
34 * struct v4l2_flash_ops - V4L2 flash operations
35 *
36 * @external_strobe_set: Setup strobing the flash by hardware pin state
37 * assertion.
38 * @intensity_to_led_brightness: Convert intensity to brightness in a device
39 * specific manner
40 * @led_brightness_to_intensity: convert brightness to intensity in a device
41 * specific manner.
42 */
43 struct v4l2_flash_ops {
44 int (*external_strobe_set)(struct v4l2_flash *v4l2_flash,
45 bool enable);
46 enum led_brightness (*intensity_to_led_brightness)
47 (struct v4l2_flash *v4l2_flash, s32 intensity);
48 s32 (*led_brightness_to_intensity)
49 (struct v4l2_flash *v4l2_flash, enum led_brightness);
50 };
51
52 /**
53 * struct v4l2_flash_config - V4L2 Flash sub-device initialization data
54 * @dev_name: the name of the media entity,
55 * unique in the system
56 * @intensity: non-flash strobe constraints for the LED
57 * @flash_faults: bitmask of flash faults that the LED flash class
58 * device can report; corresponding LED_FAULT* bit
59 * definitions are available in the header file
60 * <linux/led-class-flash.h>
61 * @has_external_strobe: external strobe capability
62 */
63 struct v4l2_flash_config {
64 char dev_name[32];
65 struct led_flash_setting intensity;
66 u32 flash_faults;
67 unsigned int has_external_strobe:1;
68 };
69
70 /**
71 * struct v4l2_flash - Flash sub-device context
72 * @fled_cdev: LED flash class device controlled by this sub-device
73 * @iled_cdev: LED class device representing indicator LED associated
74 * with the LED flash class device
75 * @ops: V4L2 specific flash ops
76 * @sd: V4L2 sub-device
77 * @hdl: flash controls handler
78 * @ctrls: array of pointers to controls, whose values define
79 * the sub-device state
80 */
81 struct v4l2_flash {
82 struct led_classdev_flash *fled_cdev;
83 struct led_classdev *iled_cdev;
84 const struct v4l2_flash_ops *ops;
85
86 struct v4l2_subdev sd;
87 struct v4l2_ctrl_handler hdl;
88 struct v4l2_ctrl **ctrls;
89 };
90
91 /**
92 * v4l2_subdev_to_v4l2_flash - Returns a &struct v4l2_flash from the
93 * &struct v4l2_subdev embedded on it.
94 *
95 * @sd: pointer to &struct v4l2_subdev
96 */
97 static inline struct v4l2_flash *v4l2_subdev_to_v4l2_flash(
98 struct v4l2_subdev *sd)
99 {
100 return container_of(sd, struct v4l2_flash, sd);
101 }
102
103 /**
104 * v4l2_ctrl_to_v4l2_flash - Returns a &struct v4l2_flash from the
105 * &struct v4l2_ctrl embedded on it.
106 *
107 * @c: pointer to &struct v4l2_ctrl
108 */
109 static inline struct v4l2_flash *v4l2_ctrl_to_v4l2_flash(struct v4l2_ctrl *c)
110 {
111 return container_of(c->handler, struct v4l2_flash, hdl);
112 }
113
114 #if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
115 /**
116 * v4l2_flash_init - initialize V4L2 flash led sub-device
117 * @dev: flash device, e.g. an I2C device
118 * @fwn: fwnode_handle of the LED, may be NULL if the same as device's
119 * @fled_cdev: LED flash class device to wrap
120 * @ops: V4L2 Flash device ops
121 * @config: initialization data for V4L2 Flash sub-device
122 *
123 * Create V4L2 Flash sub-device wrapping given LED subsystem device.
124 * The ops pointer is stored by the V4L2 flash framework. No
125 * references are held to config nor its contents once this function
126 * has returned.
127 *
128 * Returns: A valid pointer, or, when an error occurs, the return
129 * value is encoded using ERR_PTR(). Use IS_ERR() to check and
130 * PTR_ERR() to obtain the numeric return value.
131 */
132 struct v4l2_flash *v4l2_flash_init(
133 struct device *dev, struct fwnode_handle *fwn,
134 struct led_classdev_flash *fled_cdev,
135 const struct v4l2_flash_ops *ops, struct v4l2_flash_config *config);
136
137 /**
138 * v4l2_flash_indicator_init - initialize V4L2 indicator sub-device
139 * @dev: flash device, e.g. an I2C device
140 * @fwn: fwnode_handle of the LED, may be NULL if the same as device's
141 * @iled_cdev: LED flash class device representing the indicator LED
142 * @config: initialization data for V4L2 Flash sub-device
143 *
144 * Create V4L2 Flash sub-device wrapping given LED subsystem device.
145 * The ops pointer is stored by the V4L2 flash framework. No
146 * references are held to config nor its contents once this function
147 * has returned.
148 *
149 * Returns: A valid pointer, or, when an error occurs, the return
150 * value is encoded using ERR_PTR(). Use IS_ERR() to check and
151 * PTR_ERR() to obtain the numeric return value.
152 */
153 struct v4l2_flash *v4l2_flash_indicator_init(
154 struct device *dev, struct fwnode_handle *fwn,
155 struct led_classdev *iled_cdev, struct v4l2_flash_config *config);
156
157 /**
158 * v4l2_flash_release - release V4L2 Flash sub-device
159 * @v4l2_flash: the V4L2 Flash sub-device to release
160 *
161 * Release V4L2 Flash sub-device.
162 */
163 void v4l2_flash_release(struct v4l2_flash *v4l2_flash);
164
165 #else
166 static inline struct v4l2_flash *v4l2_flash_init(
167 struct device *dev, struct fwnode_handle *fwn,
168 struct led_classdev_flash *fled_cdev,
169 const struct v4l2_flash_ops *ops, struct v4l2_flash_config *config)
170 {
171 return NULL;
172 }
173
174 static inline struct v4l2_flash *v4l2_flash_indicator_init(
175 struct device *dev, struct fwnode_handle *fwn,
176 struct led_classdev *iled_cdev, struct v4l2_flash_config *config)
177 {
178 return NULL;
179 }
180
181 static inline void v4l2_flash_release(struct v4l2_flash *v4l2_flash)
182 {
183 }
184 #endif /* CONFIG_V4L2_FLASH_LED_CLASS */
185
186 #endif /* _V4L2_FLASH_H */