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
|
/*
* Media controller test application
*
* Copyright (C) 2010 Ideas on board SPRL <laurent.pinchart@ideasonboard.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
*/
#ifndef __MEDIA_H__
#define __MEDIA_H__
#include <linux/media.h>
struct media_link {
struct media_pad *source;
struct media_pad *sink;
struct media_link *twin;
__u32 flags;
__u32 padding[3];
};
struct media_pad {
struct media_entity *entity;
__u32 index;
__u32 flags;
__u32 padding[3];
};
struct media_entity {
struct media_entity_desc info;
struct media_pad *pads;
struct media_link *links;
unsigned int max_links;
unsigned int num_links;
char devname[32];
int fd;
__u32 padding[6];
};
struct media_device {
int fd;
struct media_entity *entities;
unsigned int entities_count;
__u32 padding[6];
};
/**
* @brief Open a media device.
* @param name - name (including path) of the device node.
* @param verbose - whether to print verbose information on the standard output.
*
* Open the media device referenced by @a name and enumerate entities, pads and
* links.
*
* @return A pointer to a newly allocated media_device structure instance on
* success and NULL on failure. The returned pointer must be freed with
* media_close when the device isn't needed anymore.
*/
struct media_device *media_open(const char *name, int verbose);
/**
* @brief Close a media device.
* @param media - device instance.
*
* Close the @a media device instance and free allocated resources. Access to the
* device instance is forbidden after this function returns.
*/
void media_close(struct media_device *media);
/**
* @brief Locate the pad at the other end of a link.
* @param pad - sink pad at one end of the link.
*
* Locate the source pad connected to @a pad through an enabled link. As only one
* link connected to a sink pad can be enabled at a time, the connected source
* pad is guaranteed to be unique.
*
* @return A pointer to the connected source pad, or NULL if all links connected
* to @a pad are disabled. Return NULL also if @a pad is not a sink pad.
*/
struct media_pad *media_entity_remote_source(struct media_pad *pad);
/**
* @brief Get the type of an entity.
* @param entity - the entity.
*
* @return The type of @a entity.
*/
static inline unsigned int media_entity_type(struct media_entity *entity)
{
return entity->info.type & MEDIA_ENT_TYPE_MASK;
}
/**
* @brief Find an entity by its name.
* @param media - media device.
* @param name - entity name.
* @param length - size of @a name.
*
* Search for an entity with a name equal to @a name.
*
* @return A pointer to the entity if found, or NULL otherwise.
*/
struct media_entity *media_get_entity_by_name(struct media_device *media,
const char *name, size_t length);
/**
* @brief Find an entity by its ID.
* @param media - media device.
* @param id - entity ID.
*
* Search for an entity with an ID equal to @a id.
*
* @return A pointer to the entity if found, or NULL otherwise.
*/
struct media_entity *media_get_entity_by_id(struct media_device *media,
__u32 id);
/**
* @brief Configure a link.
* @param media - media device.
* @param source - source pad at the link origin.
* @param sink - sink pad at the link target.
* @param flags - configuration flags.
*
* Locate the link between @a source and @a sink, and configure it by applying
* the new @a flags.
*
* Only the MEDIA_LINK_FLAG_ENABLED flag is writable.
*
* @return 0 on success, -1 on failure:
* -ENOENT: link not found
* - other error codes returned by MEDIA_IOC_SETUP_LINK
*/
int media_setup_link(struct media_device *media,
struct media_pad *source, struct media_pad *sink,
__u32 flags);
/**
* @brief Reset all links to the disabled state.
* @param media - media device.
*
* Disable all links in the media device. This function is usually used after
* opening a media device to reset all links to a known state.
*
* @return 0 on success, or a negative error code on failure.
*/
int media_reset_links(struct media_device *media);
/**
* @brief Parse string to a pad on the media device.
* @param media - media device.
* @param p - input string
* @param endp - pointer to string where parsing ended
*
* Parse NULL terminated string describing a pad and return its struct
* media_pad instance.
*
* @return Pointer to struct media_pad on success, NULL on failure.
*/
struct media_pad *media_parse_pad(struct media_device *media,
const char *p, char **endp);
/**
* @brief Parse string to a link on the media device.
* @param media - media device.
* @param p - input string
* @param endp - pointer to p where parsing ended
*
* Parse NULL terminated string p describing a link and return its struct
* media_link instance.
*
* @return Pointer to struct media_link on success, NULL on failure.
*/
struct media_link *media_parse_link(struct media_device *media,
const char *p, char **endp);
/**
* @brief Parse string to a link on the media device and set it up.
* @param media - media device.
* @param p - input string
*
* Parse NULL terminated string p describing a link and its configuration
* and configure the link.
*
* @return 0 on success, or a negative error code on failure.
*/
int media_parse_setup_link(struct media_device *media,
const char *p, char **endp);
/**
* @brief Parse string to link(s) on the media device and set it up.
* @param media - media device.
* @param p - input string
*
* Parse NULL terminated string p describing link(s) separated by
* commas (,) and configure the link(s).
*
* @return 0 on success, or a negative error code on failure.
*/
int media_parse_setup_links(struct media_device *media, const char *p);
#endif
|
