summaryrefslogtreecommitdiffstats
path: root/drivers/media/video/v4l2-common.c
blob: 597b8db35a135c935b07e19d5ba08d816ec91946 (plain)
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
/*
 *	Video for Linux Two
 *
 *	A generic video device interface for the LINUX operating system
 *	using a set of device structures/vectors for low level operations.
 *
 *	This file replaces the videodev.c file that comes with the
 *	regular kernel distribution.
 *
 *	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.
 *
 * Author:	Bill Dirks <bdirks@pacbell.net>
 *		based on code by Alan Cox, <alan@cymru.net>
 *
 */

/*
 * Video capture interface for Linux
 *
 *	A generic video device interface for the LINUX operating system
 *	using a set of device structures/vectors for low level operations.
 *
 *		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.
 *
 * Author:	Alan Cox, <alan@redhat.com>
 *
 * Fixes:
 */

/*
 * Video4linux 1/2 integration by Justin Schoeman
 * <justin@suntiger.ee.up.ac.za>
 * 2.4 PROCFS support ported from 2.4 kernels by
 *  Iñaki García Etxebarria <garetxe@euskalnet.net>
 * Makefile fix by "W. Michael Petullo" <mike@flyn.org>
 * 2.4 devfs support ported from 2.4 kernels by
 *  Dan Merillat <dan@merillat.org>
 * Added Gerd Knorrs v4l1 enhancements (Justin Schoeman)
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/smp_lock.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/pgtable.h>
#include <asm/io.h>
#include <asm/div64.h>

#ifdef CONFIG_KMOD
#include <linux/kmod.h>
#endif

#if defined(CONFIG_UST) || defined(CONFIG_UST_MODULE)
#include <linux/ust.h>
#endif


#include <linux/videodev.h>

MODULE_AUTHOR("Bill Dirks, Justin Schoeman, Gerd Knorr");
MODULE_DESCRIPTION("misc helper functions for v4l2 device drivers");
MODULE_LICENSE("GPL");

/*
 *
 *	V 4 L 2   D R I V E R   H E L P E R   A P I
 *
 */

/*
 *  Video Standard Operations (contributed by Michael Schimek)
 */


/* Fill in the fields of a v4l2_standard structure according to the
   'id' and 'transmission' parameters.  Returns negative on error.  */
int v4l2_video_std_construct(struct v4l2_standard *vs,
			     int id, char *name)
{
	u32 index = vs->index;

	memset(vs, 0, sizeof(struct v4l2_standard));
	vs->index = index;
	vs->id    = id;
	if (id & (V4L2_STD_NTSC | V4L2_STD_PAL_M)) {
		vs->frameperiod.numerator = 1001;
		vs->frameperiod.denominator = 30000;
		vs->framelines = 525;
	} else {
		vs->frameperiod.numerator = 1;
		vs->frameperiod.denominator = 25;
		vs->framelines = 625;
	}
	strlcpy(vs->name,name,sizeof(vs->name));
	return 0;
}


/* ----------------------------------------------------------------- */
/* priority handling                                                 */

#define V4L2_PRIO_VALID(val) (val == V4L2_PRIORITY_BACKGROUND   || \
			      val == V4L2_PRIORITY_INTERACTIVE  || \
			      val == V4L2_PRIORITY_RECORD)

int v4l2_prio_init(struct v4l2_prio_state *global)
{
	memset(global,0,sizeof(*global));
	return 0;
}

int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local,
		     enum v4l2_priority new)
{
	if (!V4L2_PRIO_VALID(new))
		return -EINVAL;
	if (*local == new)
		return 0;

	atomic_inc(&global->prios[new]);
	if (V4L2_PRIO_VALID(*local))
		atomic_dec(&global->prios[*local]);
	*local = new;
	return 0;
}

int v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local)
{
	return v4l2_prio_change(global,local,V4L2_PRIORITY_DEFAULT);
}

int v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority *local)
{
	if (V4L2_PRIO_VALID(*local))
		atomic_dec(&global->prios[*local]);
	return 0;
}

enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global)
{
	if (atomic_read(&global->prios[V4L2_PRIORITY_RECORD]) > 0)
		return V4L2_PRIORITY_RECORD;
	if (atomic_read(&global->prios[V4L2_PRIORITY_INTERACTIVE]) > 0)
		return V4L2_PRIORITY_INTERACTIVE;
	if (atomic_read(&global->prios[V4L2_PRIORITY_BACKGROUND]) > 0)
		return V4L2_PRIORITY_BACKGROUND;
	return V4L2_PRIORITY_UNSET;
}

int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority *local)
{
	if (*local < v4l2_prio_max(global))
		return -EBUSY;
	return 0;
}


/* ----------------------------------------------------------------- */
/* some arrays for pretty-printing debug messages                    */

char *v4l2_field_names[] = {
	[V4L2_FIELD_ANY]        = "any",
	[V4L2_FIELD_NONE]       = "none",
	[V4L2_FIELD_TOP]        = "top",
	[V4L2_FIELD_BOTTOM]     = "bottom",
	[V4L2_FIELD_INTERLACED] = "interlaced",
	[V4L2_FIELD_SEQ_TB]     = "seq-tb",
	[V4L2_FIELD_SEQ_BT]     = "seq-bt",
	[V4L2_FIELD_ALTERNATE]  = "alternate",
};

char *v4l2_type_names[] = {
	[V4L2_BUF_TYPE_VIDEO_CAPTURE] = "video-cap",
	[V4L2_BUF_TYPE_VIDEO_OVERLAY] = "video-over",
	[V4L2_BUF_TYPE_VIDEO_OUTPUT]  = "video-out",
	[V4L2_BUF_TYPE_VBI_CAPTURE]   = "vbi-cap",
	[V4L2_BUF_TYPE_VBI_OUTPUT]    = "vbi-out",
};

char *v4l2_ioctl_names[256] = {
#if __GNUC__ >= 3
	[0 ... 255]                      = "UNKNOWN",
#endif
	[_IOC_NR(VIDIOC_QUERYCAP)]       = "VIDIOC_QUERYCAP",
	[_IOC_NR(VIDIOC_RESERVED)]       = "VIDIOC_RESERVED",
	[_IOC_NR(VIDIOC_ENUM_FMT)]       = "VIDIOC_ENUM_FMT",
	[_IOC_NR(VIDIOC_G_FMT)]          = "VIDIOC_G_FMT",
	[_IOC_NR(VIDIOC_S_FMT)]          = "VIDIOC_S_FMT",
	[_IOC_NR(VIDIOC_REQBUFS)]        = "VIDIOC_REQBUFS",
	[_IOC_NR(VIDIOC_QUERYBUF)]       = "VIDIOC_QUERYBUF",
	[_IOC_NR(VIDIOC_G_FBUF)]         = "VIDIOC_G_FBUF",
	[_IOC_NR(VIDIOC_S_FBUF)]         = "VIDIOC_S_FBUF",
	[_IOC_NR(VIDIOC_OVERLAY)]        = "VIDIOC_OVERLAY",
	[_IOC_NR(VIDIOC_QBUF)]           = "VIDIOC_QBUF",
	[_IOC_NR(VIDIOC_DQBUF)]          = "VIDIOC_DQBUF",
	[_IOC_NR(VIDIOC_STREAMON)]       = "VIDIOC_STREAMON",
	[_IOC_NR(VIDIOC_STREAMOFF)]      = "VIDIOC_STREAMOFF",
	[_IOC_NR(VIDIOC_G_PARM)]         = "VIDIOC_G_PARM",
	[_IOC_NR(VIDIOC_S_PARM)]         = "VIDIOC_S_PARM",
	[_IOC_NR(VIDIOC_G_STD)]          = "VIDIOC_G_STD",
	[_IOC_NR(VIDIOC_S_STD)]          = "VIDIOC_S_STD",
	[_IOC_NR(VIDIOC_ENUMSTD)]        = "VIDIOC_ENUMSTD",
	[_IOC_NR(VIDIOC_ENUMINPUT)]      = "VIDIOC_ENUMINPUT",
	[_IOC_NR(VIDIOC_G_CTRL)]         = "VIDIOC_G_CTRL",
	[_IOC_NR(VIDIOC_S_CTRL)]         = "VIDIOC_S_CTRL",
	[_IOC_NR(VIDIOC_G_TUNER)]        = "VIDIOC_G_TUNER",
	[_IOC_NR(VIDIOC_S_TUNER)]        = "VIDIOC_S_TUNER",
	[_IOC_NR(VIDIOC_G_AUDIO)]        = "VIDIOC_G_AUDIO",
	[_IOC_NR(VIDIOC_S_AUDIO)]        = "VIDIOC_S_AUDIO",
	[_IOC_NR(VIDIOC_QUERYCTRL)]      = "VIDIOC_QUERYCTRL",
	[_IOC_NR(VIDIOC_QUERYMENU)]      = "VIDIOC_QUERYMENU",
	[_IOC_NR(VIDIOC_G_INPUT)]        = "VIDIOC_G_INPUT",
	[_IOC_NR(VIDIOC_S_INPUT)]        = "VIDIOC_S_INPUT",
	[_IOC_NR(VIDIOC_G_OUTPUT)]       = "VIDIOC_G_OUTPUT",
	[_IOC_NR(VIDIOC_S_OUTPUT)]       = "VIDIOC_S_OUTPUT",
	[_IOC_NR(VIDIOC_ENUMOUTPUT)]     = "VIDIOC_ENUMOUTPUT",
	[_IOC_NR(VIDIOC_G_AUDOUT)]       = "VIDIOC_G_AUDOUT",
	[_IOC_NR(VIDIOC_S_AUDOUT)]       = "VIDIOC_S_AUDOUT",
	[_IOC_NR(VIDIOC_G_MODULATOR)]    = "VIDIOC_G_MODULATOR",
	[_IOC_NR(VIDIOC_S_MODULATOR)]    = "VIDIOC_S_MODULATOR",
	[_IOC_NR(VIDIOC_G_FREQUENCY)]    = "VIDIOC_G_FREQUENCY",
	[_IOC_NR(VIDIOC_S_FREQUENCY)]    = "VIDIOC_S_FREQUENCY",
	[_IOC_NR(VIDIOC_CROPCAP)]        = "VIDIOC_CROPCAP",
	[_IOC_NR(VIDIOC_G_CROP)]         = "VIDIOC_G_CROP",
	[_IOC_NR(VIDIOC_S_CROP)]         = "VIDIOC_S_CROP",
	[_IOC_NR(VIDIOC_G_JPEGCOMP)]     = "VIDIOC_G_JPEGCOMP",
	[_IOC_NR(VIDIOC_S_JPEGCOMP)]     = "VIDIOC_S_JPEGCOMP",
	[_IOC_NR(VIDIOC_QUERYSTD)]       = "VIDIOC_QUERYSTD",
	[_IOC_NR(VIDIOC_TRY_FMT)]        = "VIDIOC_TRY_FMT",
};

/* ----------------------------------------------------------------- */

EXPORT_SYMBOL(v4l2_video_std_construct);

EXPORT_SYMBOL(v4l2_prio_init);
EXPORT_SYMBOL(v4l2_prio_change);
EXPORT_SYMBOL(v4l2_prio_open);
EXPORT_SYMBOL(v4l2_prio_close);
EXPORT_SYMBOL(v4l2_prio_max);
EXPORT_SYMBOL(v4l2_prio_check);

EXPORT_SYMBOL(v4l2_field_names);
EXPORT_SYMBOL(v4l2_type_names);
EXPORT_SYMBOL(v4l2_ioctl_names);

/*
 * Local variables:
 * c-basic-offset: 8
 * End:
 */