1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *      uvc_metadata.c  --  USB Video Class driver - Metadata handling
4 *
5 *      Copyright (C) 2016
6 *          Guennadi Liakhovetski (guennadi.liakhovetski@intel.com)
7 */
8
9#include <linux/kernel.h>
10#include <linux/list.h>
11#include <linux/module.h>
12#include <linux/usb.h>
13#include <linux/videodev2.h>
14
15#include <media/v4l2-ioctl.h>
16#include <media/videobuf2-v4l2.h>
17#include <media/videobuf2-vmalloc.h>
18
19#include "uvcvideo.h"
20
21/* -----------------------------------------------------------------------------
22 * V4L2 ioctls
23 */
24
25static int uvc_meta_v4l2_querycap(struct file *file, void *fh,
26				  struct v4l2_capability *cap)
27{
28	struct v4l2_fh *vfh = file->private_data;
29	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
30	struct uvc_video_chain *chain = stream->chain;
31
32	strscpy(cap->driver, "uvcvideo", sizeof(cap->driver));
33	strscpy(cap->card, vfh->vdev->name, sizeof(cap->card));
34	usb_make_path(stream->dev->udev, cap->bus_info, sizeof(cap->bus_info));
35	cap->capabilities = V4L2_CAP_DEVICE_CAPS | V4L2_CAP_STREAMING
36			  | chain->caps;
37
38	return 0;
39}
40
41static int uvc_meta_v4l2_get_format(struct file *file, void *fh,
42				    struct v4l2_format *format)
43{
44	struct v4l2_fh *vfh = file->private_data;
45	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
46	struct v4l2_meta_format *fmt = &format->fmt.meta;
47
48	if (format->type != vfh->vdev->queue->type)
49		return -EINVAL;
50
51	memset(fmt, 0, sizeof(*fmt));
52
53	fmt->dataformat = stream->meta.format;
54	fmt->buffersize = UVC_METADATA_BUF_SIZE;
55
56	return 0;
57}
58
59static int uvc_meta_v4l2_try_format(struct file *file, void *fh,
60				    struct v4l2_format *format)
61{
62	struct v4l2_fh *vfh = file->private_data;
63	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
64	struct uvc_device *dev = stream->dev;
65	struct v4l2_meta_format *fmt = &format->fmt.meta;
66	u32 fmeta = fmt->dataformat;
67
68	if (format->type != vfh->vdev->queue->type)
69		return -EINVAL;
70
71	memset(fmt, 0, sizeof(*fmt));
72
73	fmt->dataformat = fmeta == dev->info->meta_format
74			? fmeta : V4L2_META_FMT_UVC;
75	fmt->buffersize = UVC_METADATA_BUF_SIZE;
76
77	return 0;
78}
79
80static int uvc_meta_v4l2_set_format(struct file *file, void *fh,
81				    struct v4l2_format *format)
82{
83	struct v4l2_fh *vfh = file->private_data;
84	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
85	struct v4l2_meta_format *fmt = &format->fmt.meta;
86	int ret;
87
88	ret = uvc_meta_v4l2_try_format(file, fh, format);
89	if (ret < 0)
90		return ret;
91
92	/*
93	 * We could in principle switch at any time, also during streaming.
94	 * Metadata buffers would still be perfectly parseable, but it's more
95	 * consistent and cleaner to disallow that.
96	 */
97	mutex_lock(&stream->mutex);
98
99	if (uvc_queue_allocated(&stream->queue))
100		ret = -EBUSY;
101	else
102		stream->meta.format = fmt->dataformat;
103
104	mutex_unlock(&stream->mutex);
105
106	return ret;
107}
108
109static int uvc_meta_v4l2_enum_formats(struct file *file, void *fh,
110				      struct v4l2_fmtdesc *fdesc)
111{
112	struct v4l2_fh *vfh = file->private_data;
113	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
114	struct uvc_device *dev = stream->dev;
115	u32 index = fdesc->index;
116
117	if (fdesc->type != vfh->vdev->queue->type ||
118	    index > 1U || (index && !dev->info->meta_format))
119		return -EINVAL;
120
121	memset(fdesc, 0, sizeof(*fdesc));
122
123	fdesc->type = vfh->vdev->queue->type;
124	fdesc->index = index;
125	fdesc->pixelformat = index ? dev->info->meta_format : V4L2_META_FMT_UVC;
126
127	return 0;
128}
129
130static const struct v4l2_ioctl_ops uvc_meta_ioctl_ops = {
131	.vidioc_querycap		= uvc_meta_v4l2_querycap,
132	.vidioc_g_fmt_meta_cap		= uvc_meta_v4l2_get_format,
133	.vidioc_s_fmt_meta_cap		= uvc_meta_v4l2_set_format,
134	.vidioc_try_fmt_meta_cap	= uvc_meta_v4l2_try_format,
135	.vidioc_enum_fmt_meta_cap	= uvc_meta_v4l2_enum_formats,
136	.vidioc_reqbufs			= vb2_ioctl_reqbufs,
137	.vidioc_querybuf		= vb2_ioctl_querybuf,
138	.vidioc_qbuf			= vb2_ioctl_qbuf,
139	.vidioc_dqbuf			= vb2_ioctl_dqbuf,
140	.vidioc_create_bufs		= vb2_ioctl_create_bufs,
141	.vidioc_prepare_buf		= vb2_ioctl_prepare_buf,
142	.vidioc_streamon		= vb2_ioctl_streamon,
143	.vidioc_streamoff		= vb2_ioctl_streamoff,
144};
145
146/* -----------------------------------------------------------------------------
147 * V4L2 File Operations
148 */
149
150static const struct v4l2_file_operations uvc_meta_fops = {
151	.owner = THIS_MODULE,
152	.unlocked_ioctl = video_ioctl2,
153	.open = v4l2_fh_open,
154	.release = vb2_fop_release,
155	.poll = vb2_fop_poll,
156	.mmap = vb2_fop_mmap,
157};
158
159int uvc_meta_register(struct uvc_streaming *stream)
160{
161	struct uvc_device *dev = stream->dev;
162	struct video_device *vdev = &stream->meta.vdev;
163	struct uvc_video_queue *queue = &stream->meta.queue;
164
165	stream->meta.format = V4L2_META_FMT_UVC;
166
167	/*
168	 * The video interface queue uses manual locking and thus does not set
169	 * the queue pointer. Set it manually here.
170	 */
171	vdev->queue = &queue->queue;
172
173	return uvc_register_video_device(dev, stream, vdev, queue,
174					 V4L2_BUF_TYPE_META_CAPTURE,
175					 &uvc_meta_fops, &uvc_meta_ioctl_ops);
176}
177