aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/usb/gadget/uvc_v4l2.c
blob: f6e083b5019137db248fc67731f24eb6e683b1ac (plain) (blame)
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
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
/*
 *	uvc_v4l2.c  --  USB Video Class Gadget driver
 *
 *	Copyright (C) 2009-2010
 *	    Laurent Pinchart (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.
 */

#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/videodev2.h>
#include <linux/vmalloc.h>
#include <linux/wait.h>

#include <media/v4l2-dev.h>
#include <media/v4l2-event.h>
#include <media/v4l2-ioctl.h>

#include "uvc.h"
#include "uvc_queue.h"

/* --------------------------------------------------------------------------
 * Requests handling
 */

static int
uvc_send_response(struct uvc_device *uvc, struct uvc_request_data *data)
{
	struct usb_composite_dev *cdev = uvc->func.config->cdev;
	struct usb_request *req = uvc->control_req;

	if (data->length < 0)
		return usb_ep_set_halt(cdev->gadget->ep0);

	req->length = min(uvc->event_length, data->length);
	req->zero = data->length < uvc->event_length;
	req->dma = DMA_ADDR_INVALID;

	memcpy(req->buf, data->data, data->length);

	return usb_ep_queue(cdev->gadget->ep0, req, GFP_KERNEL);
}

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

struct uvc_format
{
	u8 bpp;
	u32 fcc;
};

static struct uvc_format uvc_formats[] = {
	{ 16, V4L2_PIX_FMT_YUYV  },
	{ 0,  V4L2_PIX_FMT_MJPEG },
};

static int
uvc_v4l2_get_format(struct uvc_video *video, struct v4l2_format *fmt)
{
	fmt->fmt.pix.pixelformat = video->fcc;
	fmt->fmt.pix.width = video->width;
	fmt->fmt.pix.height = video->height;
	fmt->fmt.pix.field = V4L2_FIELD_NONE;
	fmt->fmt.pix.bytesperline = video->bpp * video->width / 8;
	fmt->fmt.pix.sizeimage = video->imagesize;
	fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
	fmt->fmt.pix.priv = 0;

	return 0;
}

static int
uvc_v4l2_set_format(struct uvc_video *video, struct v4l2_format *fmt)
{
	struct uvc_format *format;
	unsigned int imagesize;
	unsigned int bpl;
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(uvc_formats); ++i) {
		format = &uvc_formats[i];
		if (format->fcc == fmt->fmt.pix.pixelformat)
			break;
	}

	if (i == ARRAY_SIZE(uvc_formats)) {
		printk(KERN_INFO "Unsupported format 0x%08x.\n",
			fmt->fmt.pix.pixelformat);
		return -EINVAL;
	}

	bpl = format->bpp * fmt->fmt.pix.width / 8;
	imagesize = bpl ? bpl * fmt->fmt.pix.height : fmt->fmt.pix.sizeimage;

	video->fcc = format->fcc;
	video->bpp = format->bpp;
	video->width = fmt->fmt.pix.width;
	video->height = fmt->fmt.pix.height;
	video->imagesize = imagesize;

	fmt->fmt.pix.field = V4L2_FIELD_NONE;
	fmt->fmt.pix.bytesperline = bpl;
	fmt->fmt.pix.sizeimage = imagesize;
	fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
	fmt->fmt.pix.priv = 0;

	return 0;
}

static int
uvc_v4l2_open(struct file *file)
{
	struct video_device *vdev = video_devdata(file);
	struct uvc_device *uvc = video_get_drvdata(vdev);
	struct uvc_file_handle *handle;

	handle = kzalloc(sizeof(*handle), GFP_KERNEL);
	if (handle == NULL)
		return -ENOMEM;

	v4l2_fh_init(&handle->vfh, vdev);
	v4l2_fh_add(&handle->vfh);

	handle->device = &uvc->video;
	file->private_data = &handle->vfh;

	uvc_function_connect(uvc);
	return 0;
}

static int
uvc_v4l2_release(struct file *file)
{
	struct video_device *vdev = video_devdata(file);
	struct uvc_device *uvc = video_get_drvdata(vdev);
	struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
	struct uvc_video *video = handle->device;

	uvc_function_disconnect(uvc);

	uvc_video_enable(video, 0);
	mutex_lock(&video->queue.mutex);
	if (uvc_free_buffers(&video->queue) < 0)
		printk(KERN_ERR "uvc_v4l2_release: Unable to free "
				"buffers.\n");
	mutex_unlock(&video->queue.mutex);

	file->private_data = NULL;
	v4l2_fh_del(&handle->vfh);
	v4l2_fh_exit(&handle->vfh);
	kfree(handle);
	return 0;
}

static long
uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
{
	struct video_device *vdev = video_devdata(file);
	struct uvc_device *uvc = video_get_drvdata(vdev);
	struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
	struct usb_composite_dev *cdev = uvc->func.config->cdev;
	struct uvc_video *video = &uvc->video;
	int ret = 0;

	switch (cmd) {
	/* Query capabilities */
	case VIDIOC_QUERYCAP:
	{
		struct v4l2_capability *cap = arg;

		memset(cap, 0, sizeof *cap);
		strncpy(cap->driver, "g_uvc", sizeof(cap->driver));
		strncpy(cap->card, cdev->gadget->name, sizeof(cap->card));
		strncpy(cap->bus_info, dev_name(&cdev->gadget->dev),
			sizeof cap->bus_info);
		cap->version = DRIVER_VERSION_NUMBER;
		cap->capabilities = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
		break;
	}

	/* Get & Set format */
	case VIDIOC_G_FMT:
	{
		struct v4l2_format *fmt = arg;

		if (fmt->type != video->queue.type)
			return -EINVAL;

		return uvc_v4l2_get_format(video, fmt);
	}

	case VIDIOC_S_FMT:
	{
		struct v4l2_format *fmt = arg;

		if (fmt->type != video->queue.type)
			return -EINVAL;

		return uvc_v4l2_set_format(video, fmt);
	}

	/* Buffers & streaming */
	case VIDIOC_REQBUFS:
	{
		struct v4l2_requestbuffers *rb = arg;

		if (rb->type != video->queue.type ||
		    rb->memory != V4L2_MEMORY_MMAP)
			return -EINVAL;

		ret = uvc_alloc_buffers(&video->queue, rb->count,
					video->imagesize);
		if (ret < 0)
			return ret;

		rb->count = ret;
		ret = 0;
		break;
	}

	case VIDIOC_QUERYBUF:
	{
		struct v4l2_buffer *buf = arg;

		if (buf->type != video->queue.type)
			return -EINVAL;

		return uvc_query_buffer(&video->queue, buf);
	}

	case VIDIOC_QBUF:
		if ((ret = uvc_queue_buffer(&video->queue, arg)) < 0)
			return ret;

		return uvc_video_pump(video);

	case VIDIOC_DQBUF:
		return uvc_dequeue_buffer(&video->queue, arg,
			file->f_flags & O_NONBLOCK);

	case VIDIOC_STREAMON:
	{
		int *type = arg;

		if (*type != video->queue.type)
			return -EINVAL;

		return uvc_video_enable(video, 1);
	}

	case VIDIOC_STREAMOFF:
	{
		int *type = arg;

		if (*type != video->queue.type)
			return -EINVAL;

		return uvc_video_enable(video, 0);
	}

	/* Events */
        case VIDIOC_DQEVENT:
	{
		struct v4l2_event *event = arg;

		ret = v4l2_event_dequeue(&handle->vfh, event,
					 file->f_flags & O_NONBLOCK);
		if (ret == 0 && event->type == UVC_EVENT_SETUP) {
			struct uvc_event *uvc_event = (void *)&event->u.data;

			/* Tell the complete callback to generate an event for
			 * the next request that will be enqueued by
			 * uvc_event_write.
			 */
			uvc->event_setup_out =
				!(uvc_event->req.bRequestType & USB_DIR_IN);
			uvc->event_length = uvc_event->req.wLength;
		}

		return ret;
	}

	case VIDIOC_SUBSCRIBE_EVENT:
	{
		struct v4l2_event_subscription *sub = arg;

		if (sub->type < UVC_EVENT_FIRST || sub->type > UVC_EVENT_LAST)
			return -EINVAL;

		return v4l2_event_subscribe(&handle->vfh, arg, 2);
	}

	case VIDIOC_UNSUBSCRIBE_EVENT:
		return v4l2_event_unsubscribe(&handle->vfh, arg);

	case UVCIOC_SEND_RESPONSE:
		ret = uvc_send_response(uvc, arg);
		break;

	default:
		return -ENOIOCTLCMD;
	}

	return ret;
}

static long
uvc_v4l2_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	return video_usercopy(file, cmd, arg, uvc_v4l2_do_ioctl);
}

static int
uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
{
	struct video_device *vdev = video_devdata(file);
	struct uvc_device *uvc = video_get_drvdata(vdev);

	return uvc_queue_mmap(&uvc->video.queue, vma);
}

static unsigned int
uvc_v4l2_poll(struct file *file, poll_table *wait)
{
	struct video_device *vdev = video_devdata(file);
	struct uvc_device *uvc = video_get_drvdata(vdev);
	struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
	unsigned int mask = 0;

	poll_wait(file, &handle->vfh.wait, wait);
	if (v4l2_event_pending(&handle->vfh))
		mask |= POLLPRI;

	mask |= uvc_queue_poll(&uvc->video.queue, file, wait);

	return mask;
}

static struct v4l2_file_operations uvc_v4l2_fops = {
	.owner		= THIS_MODULE,
	.open		= uvc_v4l2_open,
	.release	= uvc_v4l2_release,
	.ioctl		= uvc_v4l2_ioctl,
	.mmap		= uvc_v4l2_mmap,
	.poll		= uvc_v4l2_poll,
};