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1/*
2 * V4L2 asynchronous subdevice registration API
3 *
4 * Copyright (C) 2012-2013, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#ifndef V4L2_ASYNC_H
12#define V4L2_ASYNC_H
13
14#include <linux/list.h>
15#include <linux/mutex.h>
16
17struct device;
18struct device_node;
19struct v4l2_device;
20struct v4l2_subdev;
21struct v4l2_async_notifier;
22
23/* A random max subdevice number, used to allocate an array on stack */
24#define V4L2_MAX_SUBDEVS 128U
25
26enum v4l2_async_match_type {
27 V4L2_ASYNC_MATCH_CUSTOM,
28 V4L2_ASYNC_MATCH_DEVNAME,
29 V4L2_ASYNC_MATCH_I2C,
30 V4L2_ASYNC_MATCH_OF,
31};
32
33/**
34 * struct v4l2_async_subdev - sub-device descriptor, as known to a bridge
35 * @bus_type: subdevice bus type to select the appropriate matching method
36 * @match: union of per-bus type matching data sets
37 * @list: used to link struct v4l2_async_subdev objects, waiting to be
38 * probed, to a notifier->waiting list
39 */
40struct v4l2_async_subdev {
41 enum v4l2_async_match_type match_type;
42 union {
43 struct {
44 const struct device_node *node;
45 } of;
46 struct {
47 const char *name;
48 } device_name;
49 struct {
50 int adapter_id;
51 unsigned short address;
52 } i2c;
53 struct {
54 bool (*match)(struct device *,
55 struct v4l2_async_subdev *);
56 void *priv;
57 } custom;
58 } match;
59
60 /* v4l2-async core private: not to be used by drivers */
61 struct list_head list;
62};
63
64/**
65 * v4l2_async_notifier - v4l2_device notifier data
66 * @num_subdevs:number of subdevices
67 * @subdevs: array of pointers to subdevice descriptors
68 * @v4l2_dev: pointer to struct v4l2_device
69 * @waiting: list of struct v4l2_async_subdev, waiting for their drivers
70 * @done: list of struct v4l2_subdev, already probed
71 * @list: member in a global list of notifiers
72 * @bound: a subdevice driver has successfully probed one of subdevices
73 * @complete: all subdevices have been probed successfully
74 * @unbind: a subdevice is leaving
75 */
76struct v4l2_async_notifier {
77 unsigned int num_subdevs;
78 struct v4l2_async_subdev **subdevs;
79 struct v4l2_device *v4l2_dev;
80 struct list_head waiting;
81 struct list_head done;
82 struct list_head list;
83 int (*bound)(struct v4l2_async_notifier *notifier,
84 struct v4l2_subdev *subdev,
85 struct v4l2_async_subdev *asd);
86 int (*complete)(struct v4l2_async_notifier *notifier);
87 void (*unbind)(struct v4l2_async_notifier *notifier,
88 struct v4l2_subdev *subdev,
89 struct v4l2_async_subdev *asd);
90};
91
92int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev,
93 struct v4l2_async_notifier *notifier);
94void v4l2_async_notifier_unregister(struct v4l2_async_notifier *notifier);
95int v4l2_async_register_subdev(struct v4l2_subdev *sd);
96void v4l2_async_unregister_subdev(struct v4l2_subdev *sd);
97#endif
1/*
2 * V4L2 asynchronous subdevice registration API
3 *
4 * Copyright (C) 2012-2013, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#ifndef V4L2_ASYNC_H
12#define V4L2_ASYNC_H
13
14#include <linux/list.h>
15#include <linux/mutex.h>
16
17struct device;
18struct device_node;
19struct v4l2_device;
20struct v4l2_subdev;
21struct v4l2_async_notifier;
22
23/* A random max subdevice number, used to allocate an array on stack */
24#define V4L2_MAX_SUBDEVS 128U
25
26/**
27 * enum v4l2_async_match_type - type of asynchronous subdevice logic to be used
28 * in order to identify a match
29 *
30 * @V4L2_ASYNC_MATCH_CUSTOM: Match will use the logic provided by &struct
31 * v4l2_async_subdev.match ops
32 * @V4L2_ASYNC_MATCH_DEVNAME: Match will use the device name
33 * @V4L2_ASYNC_MATCH_I2C: Match will check for I2C adapter ID and address
34 * @V4L2_ASYNC_MATCH_FWNODE: Match will use firmware node
35 *
36 * This enum is used by the asyncrhronous sub-device logic to define the
37 * algorithm that will be used to match an asynchronous device.
38 */
39enum v4l2_async_match_type {
40 V4L2_ASYNC_MATCH_CUSTOM,
41 V4L2_ASYNC_MATCH_DEVNAME,
42 V4L2_ASYNC_MATCH_I2C,
43 V4L2_ASYNC_MATCH_FWNODE,
44};
45
46/**
47 * struct v4l2_async_subdev - sub-device descriptor, as known to a bridge
48 *
49 * @match_type: type of match that will be used
50 * @match: union of per-bus type matching data sets
51 * @match.fwnode:
52 * pointer to &struct fwnode_handle to be matched.
53 * Used if @match_type is %V4L2_ASYNC_MATCH_FWNODE.
54 * @match.device_name:
55 * string containing the device name to be matched.
56 * Used if @match_type is %V4L2_ASYNC_MATCH_DEVNAME.
57 * @match.i2c: embedded struct with I2C parameters to be matched.
58 * Both @match.i2c.adapter_id and @match.i2c.address
59 * should be matched.
60 * Used if @match_type is %V4L2_ASYNC_MATCH_I2C.
61 * @match.i2c.adapter_id:
62 * I2C adapter ID to be matched.
63 * Used if @match_type is %V4L2_ASYNC_MATCH_I2C.
64 * @match.i2c.address:
65 * I2C address to be matched.
66 * Used if @match_type is %V4L2_ASYNC_MATCH_I2C.
67 * @match.custom:
68 * Driver-specific match criteria.
69 * Used if @match_type is %V4L2_ASYNC_MATCH_CUSTOM.
70 * @match.custom.match:
71 * Driver-specific match function to be used if
72 * %V4L2_ASYNC_MATCH_CUSTOM.
73 * @match.custom.priv:
74 * Driver-specific private struct with match parameters
75 * to be used if %V4L2_ASYNC_MATCH_CUSTOM.
76 * @list: used to link struct v4l2_async_subdev objects, waiting to be
77 * probed, to a notifier->waiting list
78 *
79 * When this struct is used as a member in a driver specific struct,
80 * the driver specific struct shall contain the &struct
81 * v4l2_async_subdev as its first member.
82 */
83struct v4l2_async_subdev {
84 enum v4l2_async_match_type match_type;
85 union {
86 struct fwnode_handle *fwnode;
87 const char *device_name;
88 struct {
89 int adapter_id;
90 unsigned short address;
91 } i2c;
92 struct {
93 bool (*match)(struct device *,
94 struct v4l2_async_subdev *);
95 void *priv;
96 } custom;
97 } match;
98
99 /* v4l2-async core private: not to be used by drivers */
100 struct list_head list;
101};
102
103/**
104 * struct v4l2_async_notifier_operations - Asynchronous V4L2 notifier operations
105 * @bound: a subdevice driver has successfully probed one of the subdevices
106 * @complete: All subdevices have been probed successfully. The complete
107 * callback is only executed for the root notifier.
108 * @unbind: a subdevice is leaving
109 */
110struct v4l2_async_notifier_operations {
111 int (*bound)(struct v4l2_async_notifier *notifier,
112 struct v4l2_subdev *subdev,
113 struct v4l2_async_subdev *asd);
114 int (*complete)(struct v4l2_async_notifier *notifier);
115 void (*unbind)(struct v4l2_async_notifier *notifier,
116 struct v4l2_subdev *subdev,
117 struct v4l2_async_subdev *asd);
118};
119
120/**
121 * struct v4l2_async_notifier - v4l2_device notifier data
122 *
123 * @ops: notifier operations
124 * @num_subdevs: number of subdevices used in the subdevs array
125 * @max_subdevs: number of subdevices allocated in the subdevs array
126 * @subdevs: array of pointers to subdevice descriptors
127 * @v4l2_dev: v4l2_device of the root notifier, NULL otherwise
128 * @sd: sub-device that registered the notifier, NULL otherwise
129 * @parent: parent notifier
130 * @waiting: list of struct v4l2_async_subdev, waiting for their drivers
131 * @done: list of struct v4l2_subdev, already probed
132 * @list: member in a global list of notifiers
133 */
134struct v4l2_async_notifier {
135 const struct v4l2_async_notifier_operations *ops;
136 unsigned int num_subdevs;
137 unsigned int max_subdevs;
138 struct v4l2_async_subdev **subdevs;
139 struct v4l2_device *v4l2_dev;
140 struct v4l2_subdev *sd;
141 struct v4l2_async_notifier *parent;
142 struct list_head waiting;
143 struct list_head done;
144 struct list_head list;
145};
146
147/**
148 * v4l2_async_notifier_register - registers a subdevice asynchronous notifier
149 *
150 * @v4l2_dev: pointer to &struct v4l2_device
151 * @notifier: pointer to &struct v4l2_async_notifier
152 */
153int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev,
154 struct v4l2_async_notifier *notifier);
155
156/**
157 * v4l2_async_subdev_notifier_register - registers a subdevice asynchronous
158 * notifier for a sub-device
159 *
160 * @sd: pointer to &struct v4l2_subdev
161 * @notifier: pointer to &struct v4l2_async_notifier
162 */
163int v4l2_async_subdev_notifier_register(struct v4l2_subdev *sd,
164 struct v4l2_async_notifier *notifier);
165
166/**
167 * v4l2_async_notifier_unregister - unregisters a subdevice asynchronous notifier
168 *
169 * @notifier: pointer to &struct v4l2_async_notifier
170 */
171void v4l2_async_notifier_unregister(struct v4l2_async_notifier *notifier);
172
173/**
174 * v4l2_async_notifier_cleanup - clean up notifier resources
175 * @notifier: the notifier the resources of which are to be cleaned up
176 *
177 * Release memory resources related to a notifier, including the async
178 * sub-devices allocated for the purposes of the notifier but not the notifier
179 * itself. The user is responsible for calling this function to clean up the
180 * notifier after calling @v4l2_async_notifier_parse_fwnode_endpoints or
181 * @v4l2_fwnode_reference_parse_sensor_common.
182 *
183 * There is no harm from calling v4l2_async_notifier_cleanup in other
184 * cases as long as its memory has been zeroed after it has been
185 * allocated.
186 */
187void v4l2_async_notifier_cleanup(struct v4l2_async_notifier *notifier);
188
189/**
190 * v4l2_async_register_subdev - registers a sub-device to the asynchronous
191 * subdevice framework
192 *
193 * @sd: pointer to &struct v4l2_subdev
194 */
195int v4l2_async_register_subdev(struct v4l2_subdev *sd);
196
197/**
198 * v4l2_async_register_subdev_sensor_common - registers a sensor sub-device to
199 * the asynchronous sub-device
200 * framework and parse set up common
201 * sensor related devices
202 *
203 * @sd: pointer to struct &v4l2_subdev
204 *
205 * This function is just like v4l2_async_register_subdev() with the exception
206 * that calling it will also parse firmware interfaces for remote references
207 * using v4l2_async_notifier_parse_fwnode_sensor_common() and registers the
208 * async sub-devices. The sub-device is similarly unregistered by calling
209 * v4l2_async_unregister_subdev().
210 *
211 * While registered, the subdev module is marked as in-use.
212 *
213 * An error is returned if the module is no longer loaded on any attempts
214 * to register it.
215 */
216int __must_check v4l2_async_register_subdev_sensor_common(
217 struct v4l2_subdev *sd);
218
219/**
220 * v4l2_async_unregister_subdev - unregisters a sub-device to the asynchronous
221 * subdevice framework
222 *
223 * @sd: pointer to &struct v4l2_subdev
224 */
225void v4l2_async_unregister_subdev(struct v4l2_subdev *sd);
226#endif