summaryrefslogtreecommitdiffstats
path: root/include/media/v4l2-async.h
blob: 2e3d93f742a3b64e35767f5a2fc08caa794b5489 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * V4L2 asynchronous subdevice registration API
 *
 * Copyright (C) 2012-2013, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
 */

#ifndef V4L2_ASYNC_H
#define V4L2_ASYNC_H

#include <linux/list.h>
#include <linux/mutex.h>

struct device;
struct device_node;
struct v4l2_device;
struct v4l2_subdev;
struct v4l2_async_notifier;

/**
 * enum v4l2_async_match_type - type of asynchronous subdevice logic to be used
 *	in order to identify a match
 *
 * @V4L2_ASYNC_MATCH_CUSTOM: Match will use the logic provided by &struct
 *	v4l2_async_subdev.match ops
 * @V4L2_ASYNC_MATCH_DEVNAME: Match will use the device name
 * @V4L2_ASYNC_MATCH_I2C: Match will check for I2C adapter ID and address
 * @V4L2_ASYNC_MATCH_FWNODE: Match will use firmware node
 *
 * This enum is used by the asyncrhronous sub-device logic to define the
 * algorithm that will be used to match an asynchronous device.
 */
enum v4l2_async_match_type {
	V4L2_ASYNC_MATCH_CUSTOM,
	V4L2_ASYNC_MATCH_DEVNAME,
	V4L2_ASYNC_MATCH_I2C,
	V4L2_ASYNC_MATCH_FWNODE,
};

/**
 * struct v4l2_async_subdev - sub-device descriptor, as known to a bridge
 *
 * @match_type:	type of match that will be used
 * @match:	union of per-bus type matching data sets
 * @match.fwnode:
 *		pointer to &struct fwnode_handle to be matched.
 *		Used if @match_type is %V4L2_ASYNC_MATCH_FWNODE.
 * @match.device_name:
 *		string containing the device name to be matched.
 *		Used if @match_type is %V4L2_ASYNC_MATCH_DEVNAME.
 * @match.i2c:	embedded struct with I2C parameters to be matched.
 *		Both @match.i2c.adapter_id and @match.i2c.address
 *		should be matched.
 *		Used if @match_type is %V4L2_ASYNC_MATCH_I2C.
 * @match.i2c.adapter_id:
 *		I2C adapter ID to be matched.
 *		Used if @match_type is %V4L2_ASYNC_MATCH_I2C.
 * @match.i2c.address:
 *		I2C address to be matched.
 *		Used if @match_type is %V4L2_ASYNC_MATCH_I2C.
 * @match.custom:
 *		Driver-specific match criteria.
 *		Used if @match_type is %V4L2_ASYNC_MATCH_CUSTOM.
 * @match.custom.match:
 *		Driver-specific match function to be used if
 *		%V4L2_ASYNC_MATCH_CUSTOM.
 * @match.custom.priv:
 *		Driver-specific private struct with match parameters
 *		to be used if %V4L2_ASYNC_MATCH_CUSTOM.
 * @asd_list:	used to add struct v4l2_async_subdev objects to the
 *		master notifier @asd_list
 * @list:	used to link struct v4l2_async_subdev objects, waiting to be
 *		probed, to a notifier->waiting list
 *
 * When this struct is used as a member in a driver specific struct,
 * the driver specific struct shall contain the &struct
 * v4l2_async_subdev as its first member.
 */
struct v4l2_async_subdev {
	enum v4l2_async_match_type match_type;
	union {
		struct fwnode_handle *fwnode;
		const char *device_name;
		struct {
			int adapter_id;
			unsigned short address;
		} i2c;
		struct {
			bool (*match)(struct device *dev,
				      struct v4l2_async_subdev *sd);
			void *priv;
		} custom;
	} match;

	/* v4l2-async core private: not to be used by drivers */
	struct list_head list;
	struct list_head asd_list;
};

/**
 * struct v4l2_async_notifier_operations - Asynchronous V4L2 notifier operations
 * @bound:	a subdevice driver has successfully probed one of the subdevices
 * @complete:	All subdevices have been probed successfully. The complete
 *		callback is only executed for the root notifier.
 * @unbind:	a subdevice is leaving
 */
struct v4l2_async_notifier_operations {
	int (*bound)(struct v4l2_async_notifier *notifier,
		     struct v4l2_subdev *subdev,
		     struct v4l2_async_subdev *asd);
	int (*complete)(struct v4l2_async_notifier *notifier);
	void (*unbind)(struct v4l2_async_notifier *notifier,
		       struct v4l2_subdev *subdev,
		       struct v4l2_async_subdev *asd);
};

/**
 * struct v4l2_async_notifier - v4l2_device notifier data
 *
 * @ops:	notifier operations
 * @v4l2_dev:	v4l2_device of the root notifier, NULL otherwise
 * @sd:		sub-device that registered the notifier, NULL otherwise
 * @parent:	parent notifier
 * @asd_list:	master list of struct v4l2_async_subdev
 * @waiting:	list of struct v4l2_async_subdev, waiting for their drivers
 * @done:	list of struct v4l2_subdev, already probed
 * @list:	member in a global list of notifiers
 */
struct v4l2_async_notifier {
	const struct v4l2_async_notifier_operations *ops;
	struct v4l2_device *v4l2_dev;
	struct v4l2_subdev *sd;
	struct v4l2_async_notifier *parent;
	struct list_head asd_list;
	struct list_head waiting;
	struct list_head done;
	struct list_head list;
};

/**
 * v4l2_async_notifier_init - Initialize a notifier.
 *
 * @notifier: pointer to &struct v4l2_async_notifier
 *
 * This function initializes the notifier @asd_list. It must be called
 * before the first call to @v4l2_async_notifier_add_subdev.
 */
void v4l2_async_notifier_init(struct v4l2_async_notifier *notifier);

/**
 * v4l2_async_notifier_add_subdev - Add an async subdev to the
 *				notifier's master asd list.
 *
 * @notifier: pointer to &struct v4l2_async_notifier
 * @asd: pointer to &struct v4l2_async_subdev
 *
 * Call this function before registering a notifier to link the
 * provided asd to the notifiers master @asd_list.
 */
int v4l2_async_notifier_add_subdev(struct v4l2_async_notifier *notifier,
				   struct v4l2_async_subdev *asd);

/**
 * v4l2_async_notifier_add_fwnode_subdev - Allocate and add a fwnode async
 *				subdev to the notifier's master asd_list.
 *
 * @notifier: pointer to &struct v4l2_async_notifier
 * @fwnode: fwnode handle of the sub-device to be matched
 * @asd_struct_size: size of the driver's async sub-device struct, including
 *		     sizeof(struct v4l2_async_subdev). The &struct
 *		     v4l2_async_subdev shall be the first member of
 *		     the driver's async sub-device struct, i.e. both
 *		     begin at the same memory address.
 *
 * Allocate a fwnode-matched asd of size asd_struct_size, and add it
 * to the notifiers @asd_list.
 */
struct v4l2_async_subdev *
v4l2_async_notifier_add_fwnode_subdev(struct v4l2_async_notifier *notifier,
				      struct fwnode_handle *fwnode,
				      unsigned int asd_struct_size);

/**
 * v4l2_async_notifier_add_i2c_subdev - Allocate and add an i2c async
 *				subdev to the notifier's master asd_list.
 *
 * @notifier: pointer to &struct v4l2_async_notifier
 * @adapter_id: I2C adapter ID to be matched
 * @address: I2C address of sub-device to be matched
 * @asd_struct_size: size of the driver's async sub-device struct, including
 *		     sizeof(struct v4l2_async_subdev). The &struct
 *		     v4l2_async_subdev shall be the first member of
 *		     the driver's async sub-device struct, i.e. both
 *		     begin at the same memory address.
 *
 * Same as above but for I2C matched sub-devices.
 */
struct v4l2_async_subdev *
v4l2_async_notifier_add_i2c_subdev(struct v4l2_async_notifier *notifier,
				   int adapter_id, unsigned short address,
				   unsigned int asd_struct_size);

/**
 * v4l2_async_notifier_add_devname_subdev - Allocate and add a device-name
 *				async subdev to the notifier's master asd_list.
 *
 * @notifier: pointer to &struct v4l2_async_notifier
 * @device_name: device name string to be matched
 * @asd_struct_size: size of the driver's async sub-device struct, including
 *		     sizeof(struct v4l2_async_subdev). The &struct
 *		     v4l2_async_subdev shall be the first member of
 *		     the driver's async sub-device struct, i.e. both
 *		     begin at the same memory address.
 *
 * Same as above but for device-name matched sub-devices.
 */
struct v4l2_async_subdev *
v4l2_async_notifier_add_devname_subdev(struct v4l2_async_notifier *notifier,
				       const char *device_name,
				       unsigned int asd_struct_size);

/**
 * v4l2_async_notifier_register - registers a subdevice asynchronous notifier
 *
 * @v4l2_dev: pointer to &struct v4l2_device
 * @notifier: pointer to &struct v4l2_async_notifier
 */
int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev,
				 struct v4l2_async_notifier *notifier);

/**
 * v4l2_async_subdev_notifier_register - registers a subdevice asynchronous
 *					 notifier for a sub-device
 *
 * @sd: pointer to &struct v4l2_subdev
 * @notifier: pointer to &struct v4l2_async_notifier
 */
int v4l2_async_subdev_notifier_register(struct v4l2_subdev *sd,
					struct v4l2_async_notifier *notifier);

/**
 * v4l2_async_notifier_unregister - unregisters a subdevice
 *	asynchronous notifier
 *
 * @notifier: pointer to &struct v4l2_async_notifier
 */
void v4l2_async_notifier_unregister(struct v4l2_async_notifier *notifier);

/**
 * v4l2_async_notifier_cleanup - clean up notifier resources
 * @notifier: the notifier the resources of which are to be cleaned up
 *
 * Release memory resources related to a notifier, including the async
 * sub-devices allocated for the purposes of the notifier but not the notifier
 * itself. The user is responsible for calling this function to clean up the
 * notifier after calling
 * @v4l2_async_notifier_add_subdev,
 * @v4l2_async_notifier_parse_fwnode_endpoints or
 * @v4l2_fwnode_reference_parse_sensor_common.
 *
 * There is no harm from calling v4l2_async_notifier_cleanup in other
 * cases as long as its memory has been zeroed after it has been
 * allocated.
 */
void v4l2_async_notifier_cleanup(struct v4l2_async_notifier *notifier);

/**
 * v4l2_async_register_subdev - registers a sub-device to the asynchronous
 *	subdevice framework
 *
 * @sd: pointer to &struct v4l2_subdev
 */
int v4l2_async_register_subdev(struct v4l2_subdev *sd);

/**
 * v4l2_async_register_subdev_sensor_common - registers a sensor sub-device to
 *					      the asynchronous sub-device
 *					      framework and parse set up common
 *					      sensor related devices
 *
 * @sd: pointer to struct &v4l2_subdev
 *
 * This function is just like v4l2_async_register_subdev() with the exception
 * that calling it will also parse firmware interfaces for remote references
 * using v4l2_async_notifier_parse_fwnode_sensor_common() and registers the
 * async sub-devices. The sub-device is similarly unregistered by calling
 * v4l2_async_unregister_subdev().
 *
 * While registered, the subdev module is marked as in-use.
 *
 * An error is returned if the module is no longer loaded on any attempts
 * to register it.
 */
int __must_check
v4l2_async_register_subdev_sensor_common(struct v4l2_subdev *sd);

/**
 * v4l2_async_unregister_subdev - unregisters a sub-device to the asynchronous
 *	subdevice framework
 *
 * @sd: pointer to &struct v4l2_subdev
 */
void v4l2_async_unregister_subdev(struct v4l2_subdev *sd);
#endif