xref: /linux/include/media/v4l2-flash-led-class.h (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 struct v4l2_flash_ops {
37 	/* setup strobing the flash by hardware pin state assertion */
38 	int (*external_strobe_set)(struct v4l2_flash *v4l2_flash,
39 					bool enable);
40 	/* convert intensity to brightness in a device specific manner */
41 	enum led_brightness (*intensity_to_led_brightness)
42 		(struct v4l2_flash *v4l2_flash, s32 intensity);
43 	/* convert brightness to intensity in a device specific manner */
44 	s32 (*led_brightness_to_intensity)
45 		(struct v4l2_flash *v4l2_flash, enum led_brightness);
46 };
47 
48 /**
49  * struct v4l2_flash_config - V4L2 Flash sub-device initialization data
50  * @dev_name:			the name of the media entity,
51  *				unique in the system
52  * @torch_intensity:		constraints for the LED in torch mode
53  * @indicator_intensity:	constraints for the indicator LED
54  * @flash_faults:		bitmask of flash faults that the LED flash class
55  *				device can report; corresponding LED_FAULT* bit
56  *				definitions are available in the header file
57  *				<linux/led-class-flash.h>
58  * @has_external_strobe:	external strobe capability
59  */
60 struct v4l2_flash_config {
61 	char dev_name[32];
62 	struct led_flash_setting torch_intensity;
63 	struct led_flash_setting indicator_intensity;
64 	u32 flash_faults;
65 	unsigned int has_external_strobe:1;
66 };
67 
68 /**
69  * struct v4l2_flash - Flash sub-device context
70  * @fled_cdev:		LED flash class device controlled by this sub-device
71  * @iled_cdev:		LED class device representing indicator LED associated
72  *			with the LED flash class device
73  * @ops:		V4L2 specific flash ops
74  * @sd:			V4L2 sub-device
75  * @hdl:		flash controls handler
76  * @ctrls:		array of pointers to controls, whose values define
77  *			the sub-device state
78  */
79 struct v4l2_flash {
80 	struct led_classdev_flash *fled_cdev;
81 	struct led_classdev_flash *iled_cdev;
82 	const struct v4l2_flash_ops *ops;
83 
84 	struct v4l2_subdev sd;
85 	struct v4l2_ctrl_handler hdl;
86 	struct v4l2_ctrl **ctrls;
87 };
88 
89 static inline struct v4l2_flash *v4l2_subdev_to_v4l2_flash(
90 							struct v4l2_subdev *sd)
91 {
92 	return container_of(sd, struct v4l2_flash, sd);
93 }
94 
95 static inline struct v4l2_flash *v4l2_ctrl_to_v4l2_flash(struct v4l2_ctrl *c)
96 {
97 	return container_of(c->handler, struct v4l2_flash, hdl);
98 }
99 
100 #if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
101 /**
102  * v4l2_flash_init - initialize V4L2 flash led sub-device
103  * @dev:	flash device, e.g. an I2C device
104  * @of_node:	of_node of the LED, may be NULL if the same as device's
105  * @fled_cdev:	LED flash class device to wrap
106  * @iled_cdev:	LED flash class device representing indicator LED associated
107  *		with fled_cdev, may be NULL
108  * @ops:	V4L2 Flash device ops
109  * @config:	initialization data for V4L2 Flash sub-device
110  *
111  * Create V4L2 Flash sub-device wrapping given LED subsystem device.
112  *
113  * Returns: A valid pointer, or, when an error occurs, the return
114  * value is encoded using ERR_PTR(). Use IS_ERR() to check and
115  * PTR_ERR() to obtain the numeric return value.
116  */
117 struct v4l2_flash *v4l2_flash_init(
118 	struct device *dev, struct device_node *of_node,
119 	struct led_classdev_flash *fled_cdev,
120 	struct led_classdev_flash *iled_cdev,
121 	const struct v4l2_flash_ops *ops,
122 	struct v4l2_flash_config *config);
123 
124 /**
125  * v4l2_flash_release - release V4L2 Flash sub-device
126  * @v4l2_flash: the V4L2 Flash sub-device to release
127  *
128  * Release V4L2 Flash sub-device.
129  */
130 void v4l2_flash_release(struct v4l2_flash *v4l2_flash);
131 
132 #else
133 static inline struct v4l2_flash *v4l2_flash_init(
134 	struct device *dev, struct device_node *of_node,
135 	struct led_classdev_flash *fled_cdev,
136 	struct led_classdev_flash *iled_cdev,
137 	const struct v4l2_flash_ops *ops,
138 	struct v4l2_flash_config *config)
139 {
140 	return NULL;
141 }
142 
143 static inline void v4l2_flash_release(struct v4l2_flash *v4l2_flash)
144 {
145 }
146 #endif /* CONFIG_V4L2_FLASH_LED_CLASS */
147 
148 #endif /* _V4L2_FLASH_H */
149