summaryrefslogtreecommitdiffstats
path: root/drivers/media/usb/uvc/uvc_metadata.c
blob: b6279ad7ac8452087018a44143fb6c184ae0ca3f (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
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *      uvc_metadata.c  --  USB Video Class driver - Metadata handling
 *
 *      Copyright (C) 2016
 *          Guennadi Liakhovetski (guennadi.liakhovetski@intel.com)
 */

#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/videodev2.h>

#include <media/v4l2-ioctl.h>
#include <media/videobuf2-v4l2.h>
#include <media/videobuf2-vmalloc.h>

#include "uvcvideo.h"

/* -----------------------------------------------------------------------------
 * V4L2 ioctls
 */

static int uvc_meta_v4l2_querycap(struct file *file, void *fh,
				  struct v4l2_capability *cap)
{
	struct v4l2_fh *vfh = file->private_data;
	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
	struct uvc_video_chain *chain = stream->chain;

	strscpy(cap->driver, "uvcvideo", sizeof(cap->driver));
	strscpy(cap->card, vfh->vdev->name, sizeof(cap->card));
	usb_make_path(stream->dev->udev, cap->bus_info, sizeof(cap->bus_info));
	cap->capabilities = V4L2_CAP_DEVICE_CAPS | V4L2_CAP_STREAMING
			  | chain->caps;

	return 0;
}

static int uvc_meta_v4l2_get_format(struct file *file, void *fh,
				    struct v4l2_format *format)
{
	struct v4l2_fh *vfh = file->private_data;
	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
	struct v4l2_meta_format *fmt = &format->fmt.meta;

	if (format->type != vfh->vdev->queue->type)
		return -EINVAL;

	memset(fmt, 0, sizeof(*fmt));

	fmt->dataformat = stream->meta.format;
	fmt->buffersize = UVC_METADATA_BUF_SIZE;

	return 0;
}

static int uvc_meta_v4l2_try_format(struct file *file, void *fh,
				    struct v4l2_format *format)
{
	struct v4l2_fh *vfh = file->private_data;
	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
	struct uvc_device *dev = stream->dev;
	struct v4l2_meta_format *fmt = &format->fmt.meta;
	u32 fmeta = fmt->dataformat;

	if (format->type != vfh->vdev->queue->type)
		return -EINVAL;

	memset(fmt, 0, sizeof(*fmt));

	fmt->dataformat = fmeta == dev->info->meta_format
			? fmeta : V4L2_META_FMT_UVC;
	fmt->buffersize = UVC_METADATA_BUF_SIZE;

	return 0;
}

static int uvc_meta_v4l2_set_format(struct file *file, void *fh,
				    struct v4l2_format *format)
{
	struct v4l2_fh *vfh = file->private_data;
	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
	struct v4l2_meta_format *fmt = &format->fmt.meta;
	int ret;

	ret = uvc_meta_v4l2_try_format(file, fh, format);
	if (ret < 0)
		return ret;

	/*
	 * We could in principle switch at any time, also during streaming.
	 * Metadata buffers would still be perfectly parseable, but it's more
	 * consistent and cleaner to disallow that.
	 */
	mutex_lock(&stream->mutex);

	if (uvc_queue_allocated(&stream->queue))
		ret = -EBUSY;
	else
		stream->meta.format = fmt->dataformat;

	mutex_unlock(&stream->mutex);

	return ret;
}

static int uvc_meta_v4l2_enum_formats(struct file *file, void *fh,
				      struct v4l2_fmtdesc *fdesc)
{
	struct v4l2_fh *vfh = file->private_data;
	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
	struct uvc_device *dev = stream->dev;
	u32 index = fdesc->index;

	if (fdesc->type != vfh->vdev->queue->type ||
	    index > 1U || (index && !dev->info->meta_format))
		return -EINVAL;

	memset(fdesc, 0, sizeof(*fdesc));

	fdesc->type = vfh->vdev->queue->type;
	fdesc->index = index;
	fdesc->pixelformat = index ? dev->info->meta_format : V4L2_META_FMT_UVC;

	return 0;
}

static const struct v4l2_ioctl_ops uvc_meta_ioctl_ops = {
	.vidioc_querycap		= uvc_meta_v4l2_querycap,
	.vidioc_g_fmt_meta_cap		= uvc_meta_v4l2_get_format,
	.vidioc_s_fmt_meta_cap		= uvc_meta_v4l2_set_format,
	.vidioc_try_fmt_meta_cap	= uvc_meta_v4l2_try_format,
	.vidioc_enum_fmt_meta_cap	= uvc_meta_v4l2_enum_formats,
	.vidioc_reqbufs			= vb2_ioctl_reqbufs,
	.vidioc_querybuf		= vb2_ioctl_querybuf,
	.vidioc_qbuf			= vb2_ioctl_qbuf,
	.vidioc_dqbuf			= vb2_ioctl_dqbuf,
	.vidioc_create_bufs		= vb2_ioctl_create_bufs,
	.vidioc_prepare_buf		= vb2_ioctl_prepare_buf,
	.vidioc_streamon		= vb2_ioctl_streamon,
	.vidioc_streamoff		= vb2_ioctl_streamoff,
};

/* -----------------------------------------------------------------------------
 * V4L2 File Operations
 */

static const struct v4l2_file_operations uvc_meta_fops = {
	.owner = THIS_MODULE,
	.unlocked_ioctl = video_ioctl2,
	.open = v4l2_fh_open,
	.release = vb2_fop_release,
	.poll = vb2_fop_poll,
	.mmap = vb2_fop_mmap,
};

int uvc_meta_register(struct uvc_streaming *stream)
{
	struct uvc_device *dev = stream->dev;
	struct video_device *vdev = &stream->meta.vdev;
	struct uvc_video_queue *queue = &stream->meta.queue;

	stream->meta.format = V4L2_META_FMT_UVC;

	/*
	 * The video interface queue uses manual locking and thus does not set
	 * the queue pointer. Set it manually here.
	 */
	vdev->queue = &queue->queue;

	return uvc_register_video_device(dev, stream, vdev, queue,
					 V4L2_BUF_TYPE_META_CAPTURE,
					 &uvc_meta_fops, &uvc_meta_ioctl_ops);
}