1 /*
2  * V4L2 flash LED sub-device registration helpers.
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 _V4L2_FLASH_H
13 #define _V4L2_FLASH_H
14 
15 #include <media/v4l2-ctrls.h>
16 #include <media/v4l2-subdev.h>
17 
18 struct led_classdev_flash;
19 struct led_classdev;
20 struct v4l2_flash;
21 enum led_brightness;
22 
23 /**
24  * struct v4l2_flash_ctrl_data - flash control initialization data, filled
25  *				basing on the features declared by the LED flash
26  *				class driver in the v4l2_flash_config
27  * @config:	initialization data for a control
28  * @cid:	contains v4l2 flash control id if the config
29  *		field was initialized, 0 otherwise
30  */
31 struct v4l2_flash_ctrl_data {
32 	struct v4l2_ctrl_config config;
33 	u32 cid;
34 };
35 
36 /**
37  * struct v4l2_flash_ops - V4L2 flash operations
38  *
39  * @external_strobe_set: Setup strobing the flash by hardware pin state
40  *	assertion.
41  * @intensity_to_led_brightness: Convert intensity to brightness in a device
42  *	specific manner
43  * @led_brightness_to_intensity: convert brightness to intensity in a device
44  *	specific manner.
45  */
46 struct v4l2_flash_ops {
47 	int (*external_strobe_set)(struct v4l2_flash *v4l2_flash,
48 					bool enable);
49 	enum led_brightness (*intensity_to_led_brightness)
50 		(struct v4l2_flash *v4l2_flash, s32 intensity);
51 	s32 (*led_brightness_to_intensity)
52 		(struct v4l2_flash *v4l2_flash, enum led_brightness);
53 };
54 
55 /**
56  * struct v4l2_flash_config - V4L2 Flash sub-device initialization data
57  * @dev_name:			the name of the media entity,
58  *				unique in the system
59  * @intensity:			non-flash strobe constraints for the LED
60  * @flash_faults:		bitmask of flash faults that the LED flash class
61  *				device can report; corresponding LED_FAULT* bit
62  *				definitions are available in the header file
63  *				<linux/led-class-flash.h>
64  * @has_external_strobe:	external strobe capability
65  */
66 struct v4l2_flash_config {
67 	char dev_name[32];
68 	struct led_flash_setting intensity;
69 	u32 flash_faults;
70 	unsigned int has_external_strobe:1;
71 };
72 
73 /**
74  * struct v4l2_flash - Flash sub-device context
75  * @fled_cdev:		LED flash class device controlled by this sub-device
76  * @iled_cdev:		LED class device representing indicator LED associated
77  *			with the LED flash class device
78  * @ops:		V4L2 specific flash ops
79  * @sd:			V4L2 sub-device
80  * @hdl:		flash controls handler
81  * @ctrls:		array of pointers to controls, whose values define
82  *			the sub-device state
83  */
84 struct v4l2_flash {
85 	struct led_classdev_flash *fled_cdev;
86 	struct led_classdev *iled_cdev;
87 	const struct v4l2_flash_ops *ops;
88 
89 	struct v4l2_subdev sd;
90 	struct v4l2_ctrl_handler hdl;
91 	struct v4l2_ctrl **ctrls;
92 };
93 
94 /**
95  * v4l2_subdev_to_v4l2_flash - Returns a &struct v4l2_flash from the
96  * &struct v4l2_subdev embedded on it.
97  *
98  * @sd: pointer to &struct v4l2_subdev
99  */
100 static inline struct v4l2_flash *v4l2_subdev_to_v4l2_flash(
101 							struct v4l2_subdev *sd)
102 {
103 	return container_of(sd, struct v4l2_flash, sd);
104 }
105 
106 /**
107  * v4l2_ctrl_to_v4l2_flash - Returns a &struct v4l2_flash from the
108  * &struct v4l2_ctrl embedded on it.
109  *
110  * @c: pointer to &struct v4l2_ctrl
111  */
112 static inline struct v4l2_flash *v4l2_ctrl_to_v4l2_flash(struct v4l2_ctrl *c)
113 {
114 	return container_of(c->handler, struct v4l2_flash, hdl);
115 }
116 
117 #if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
118 /**
119  * v4l2_flash_init - initialize V4L2 flash led sub-device
120  * @dev:	flash device, e.g. an I2C device
121  * @fwn:	fwnode_handle of the LED, may be NULL if the same as device's
122  * @fled_cdev:	LED flash class device to wrap
123  * @ops:	V4L2 Flash device ops
124  * @config:	initialization data for V4L2 Flash sub-device
125  *
126  * Create V4L2 Flash sub-device wrapping given LED subsystem device.
127  * The ops pointer is stored by the V4L2 flash framework. No
128  * references are held to config nor its contents once this function
129  * has returned.
130  *
131  * Returns: A valid pointer, or, when an error occurs, the return
132  * value is encoded using ERR_PTR(). Use IS_ERR() to check and
133  * PTR_ERR() to obtain the numeric return value.
134  */
135 struct v4l2_flash *v4l2_flash_init(
136 	struct device *dev, struct fwnode_handle *fwn,
137 	struct led_classdev_flash *fled_cdev,
138 	const struct v4l2_flash_ops *ops, struct v4l2_flash_config *config);
139 
140 /**
141  * v4l2_flash_indicator_init - initialize V4L2 indicator sub-device
142  * @dev:	flash device, e.g. an I2C device
143  * @fwn:	fwnode_handle of the LED, may be NULL if the same as device's
144  * @iled_cdev:	LED flash class device representing the indicator LED
145  * @config:	initialization data for V4L2 Flash sub-device
146  *
147  * Create V4L2 Flash sub-device wrapping given LED subsystem device.
148  * The ops pointer is stored by the V4L2 flash framework. No
149  * references are held to config nor its contents once this function
150  * has returned.
151  *
152  * Returns: A valid pointer, or, when an error occurs, the return
153  * value is encoded using ERR_PTR(). Use IS_ERR() to check and
154  * PTR_ERR() to obtain the numeric return value.
155  */
156 struct v4l2_flash *v4l2_flash_indicator_init(
157 	struct device *dev, struct fwnode_handle *fwn,
158 	struct led_classdev *iled_cdev, struct v4l2_flash_config *config);
159 
160 /**
161  * v4l2_flash_release - release V4L2 Flash sub-device
162  * @v4l2_flash: the V4L2 Flash sub-device to release
163  *
164  * Release V4L2 Flash sub-device.
165  */
166 void v4l2_flash_release(struct v4l2_flash *v4l2_flash);
167 
168 #else
169 static inline struct v4l2_flash *v4l2_flash_init(
170 	struct device *dev, struct fwnode_handle *fwn,
171 	struct led_classdev_flash *fled_cdev,
172 	const struct v4l2_flash_ops *ops, struct v4l2_flash_config *config)
173 {
174 	return NULL;
175 }
176 
177 static inline struct v4l2_flash *v4l2_flash_indicator_init(
178 	struct device *dev, struct fwnode_handle *fwn,
179 	struct led_classdev *iled_cdev, struct v4l2_flash_config *config)
180 {
181 	return NULL;
182 }
183 
184 static inline void v4l2_flash_release(struct v4l2_flash *v4l2_flash)
185 {
186 }
187 #endif /* CONFIG_V4L2_FLASH_LED_CLASS */
188 
189 #endif /* _V4L2_FLASH_H */
190