xref: /linux/drivers/usb/gadget/function/uvc_v4l2.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  *	uvc_v4l2.c  --  USB Video Class Gadget driver
3  *
4  *	Copyright (C) 2009-2010
5  *	    Laurent Pinchart (laurent.pinchart@ideasonboard.com)
6  *
7  *	This program is free software; you can redistribute it and/or modify
8  *	it under the terms of the GNU General Public License as published by
9  *	the Free Software Foundation; either version 2 of the License, or
10  *	(at your option) any later version.
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/device.h>
15 #include <linux/errno.h>
16 #include <linux/list.h>
17 #include <linux/videodev2.h>
18 #include <linux/vmalloc.h>
19 #include <linux/wait.h>
20 
21 #include <media/v4l2-dev.h>
22 #include <media/v4l2-event.h>
23 #include <media/v4l2-ioctl.h>
24 
25 #include "f_uvc.h"
26 #include "uvc.h"
27 #include "uvc_queue.h"
28 #include "uvc_video.h"
29 #include "uvc_v4l2.h"
30 
31 /* --------------------------------------------------------------------------
32  * Requests handling
33  */
34 
35 static int
36 uvc_send_response(struct uvc_device *uvc, struct uvc_request_data *data)
37 {
38 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
39 	struct usb_request *req = uvc->control_req;
40 
41 	if (data->length < 0)
42 		return usb_ep_set_halt(cdev->gadget->ep0);
43 
44 	req->length = min_t(unsigned int, uvc->event_length, data->length);
45 	req->zero = data->length < uvc->event_length;
46 
47 	memcpy(req->buf, data->data, req->length);
48 
49 	return usb_ep_queue(cdev->gadget->ep0, req, GFP_KERNEL);
50 }
51 
52 /* --------------------------------------------------------------------------
53  * V4L2 ioctls
54  */
55 
56 struct uvc_format
57 {
58 	u8 bpp;
59 	u32 fcc;
60 };
61 
62 static struct uvc_format uvc_formats[] = {
63 	{ 16, V4L2_PIX_FMT_YUYV  },
64 	{ 0,  V4L2_PIX_FMT_MJPEG },
65 };
66 
67 static int
68 uvc_v4l2_querycap(struct file *file, void *fh, struct v4l2_capability *cap)
69 {
70 	struct video_device *vdev = video_devdata(file);
71 	struct uvc_device *uvc = video_get_drvdata(vdev);
72 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
73 
74 	strlcpy(cap->driver, "g_uvc", sizeof(cap->driver));
75 	strlcpy(cap->card, cdev->gadget->name, sizeof(cap->card));
76 	strlcpy(cap->bus_info, dev_name(&cdev->gadget->dev),
77 		sizeof(cap->bus_info));
78 
79 	cap->device_caps = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
80 	cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
81 
82 	return 0;
83 }
84 
85 static int
86 uvc_v4l2_get_format(struct file *file, void *fh, struct v4l2_format *fmt)
87 {
88 	struct video_device *vdev = video_devdata(file);
89 	struct uvc_device *uvc = video_get_drvdata(vdev);
90 	struct uvc_video *video = &uvc->video;
91 
92 	fmt->fmt.pix.pixelformat = video->fcc;
93 	fmt->fmt.pix.width = video->width;
94 	fmt->fmt.pix.height = video->height;
95 	fmt->fmt.pix.field = V4L2_FIELD_NONE;
96 	fmt->fmt.pix.bytesperline = video->bpp * video->width / 8;
97 	fmt->fmt.pix.sizeimage = video->imagesize;
98 	fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
99 	fmt->fmt.pix.priv = 0;
100 
101 	return 0;
102 }
103 
104 static int
105 uvc_v4l2_set_format(struct file *file, void *fh, struct v4l2_format *fmt)
106 {
107 	struct video_device *vdev = video_devdata(file);
108 	struct uvc_device *uvc = video_get_drvdata(vdev);
109 	struct uvc_video *video = &uvc->video;
110 	struct uvc_format *format;
111 	unsigned int imagesize;
112 	unsigned int bpl;
113 	unsigned int i;
114 
115 	for (i = 0; i < ARRAY_SIZE(uvc_formats); ++i) {
116 		format = &uvc_formats[i];
117 		if (format->fcc == fmt->fmt.pix.pixelformat)
118 			break;
119 	}
120 
121 	if (i == ARRAY_SIZE(uvc_formats)) {
122 		printk(KERN_INFO "Unsupported format 0x%08x.\n",
123 			fmt->fmt.pix.pixelformat);
124 		return -EINVAL;
125 	}
126 
127 	bpl = format->bpp * fmt->fmt.pix.width / 8;
128 	imagesize = bpl ? bpl * fmt->fmt.pix.height : fmt->fmt.pix.sizeimage;
129 
130 	video->fcc = format->fcc;
131 	video->bpp = format->bpp;
132 	video->width = fmt->fmt.pix.width;
133 	video->height = fmt->fmt.pix.height;
134 	video->imagesize = imagesize;
135 
136 	fmt->fmt.pix.field = V4L2_FIELD_NONE;
137 	fmt->fmt.pix.bytesperline = bpl;
138 	fmt->fmt.pix.sizeimage = imagesize;
139 	fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
140 	fmt->fmt.pix.priv = 0;
141 
142 	return 0;
143 }
144 
145 static int
146 uvc_v4l2_reqbufs(struct file *file, void *fh, struct v4l2_requestbuffers *b)
147 {
148 	struct video_device *vdev = video_devdata(file);
149 	struct uvc_device *uvc = video_get_drvdata(vdev);
150 	struct uvc_video *video = &uvc->video;
151 
152 	if (b->type != video->queue.queue.type)
153 		return -EINVAL;
154 
155 	return uvcg_alloc_buffers(&video->queue, b);
156 }
157 
158 static int
159 uvc_v4l2_querybuf(struct file *file, void *fh, struct v4l2_buffer *b)
160 {
161 	struct video_device *vdev = video_devdata(file);
162 	struct uvc_device *uvc = video_get_drvdata(vdev);
163 	struct uvc_video *video = &uvc->video;
164 
165 	return uvcg_query_buffer(&video->queue, b);
166 }
167 
168 static int
169 uvc_v4l2_qbuf(struct file *file, void *fh, struct v4l2_buffer *b)
170 {
171 	struct video_device *vdev = video_devdata(file);
172 	struct uvc_device *uvc = video_get_drvdata(vdev);
173 	struct uvc_video *video = &uvc->video;
174 	int ret;
175 
176 	ret = uvcg_queue_buffer(&video->queue, b);
177 	if (ret < 0)
178 		return ret;
179 
180 	return uvcg_video_pump(video);
181 }
182 
183 static int
184 uvc_v4l2_dqbuf(struct file *file, void *fh, struct v4l2_buffer *b)
185 {
186 	struct video_device *vdev = video_devdata(file);
187 	struct uvc_device *uvc = video_get_drvdata(vdev);
188 	struct uvc_video *video = &uvc->video;
189 
190 	return uvcg_dequeue_buffer(&video->queue, b, file->f_flags & O_NONBLOCK);
191 }
192 
193 static int
194 uvc_v4l2_streamon(struct file *file, void *fh, enum v4l2_buf_type type)
195 {
196 	struct video_device *vdev = video_devdata(file);
197 	struct uvc_device *uvc = video_get_drvdata(vdev);
198 	struct uvc_video *video = &uvc->video;
199 	int ret;
200 
201 	if (type != video->queue.queue.type)
202 		return -EINVAL;
203 
204 	/* Enable UVC video. */
205 	ret = uvcg_video_enable(video, 1);
206 	if (ret < 0)
207 		return ret;
208 
209 	/*
210 	 * Complete the alternate setting selection setup phase now that
211 	 * userspace is ready to provide video frames.
212 	 */
213 	uvc_function_setup_continue(uvc);
214 	uvc->state = UVC_STATE_STREAMING;
215 
216 	return 0;
217 }
218 
219 static int
220 uvc_v4l2_streamoff(struct file *file, void *fh, enum v4l2_buf_type type)
221 {
222 	struct video_device *vdev = video_devdata(file);
223 	struct uvc_device *uvc = video_get_drvdata(vdev);
224 	struct uvc_video *video = &uvc->video;
225 
226 	if (type != video->queue.queue.type)
227 		return -EINVAL;
228 
229 	return uvcg_video_enable(video, 0);
230 }
231 
232 static int
233 uvc_v4l2_subscribe_event(struct v4l2_fh *fh,
234 			 const struct v4l2_event_subscription *sub)
235 {
236 	if (sub->type < UVC_EVENT_FIRST || sub->type > UVC_EVENT_LAST)
237 		return -EINVAL;
238 
239 	return v4l2_event_subscribe(fh, sub, 2, NULL);
240 }
241 
242 static int
243 uvc_v4l2_unsubscribe_event(struct v4l2_fh *fh,
244 			   const struct v4l2_event_subscription *sub)
245 {
246 	return v4l2_event_unsubscribe(fh, sub);
247 }
248 
249 static long
250 uvc_v4l2_ioctl_default(struct file *file, void *fh, bool valid_prio,
251 		       unsigned int cmd, void *arg)
252 {
253 	struct video_device *vdev = video_devdata(file);
254 	struct uvc_device *uvc = video_get_drvdata(vdev);
255 
256 	switch (cmd) {
257 	case UVCIOC_SEND_RESPONSE:
258 		return uvc_send_response(uvc, arg);
259 
260 	default:
261 		return -ENOIOCTLCMD;
262 	}
263 }
264 
265 const struct v4l2_ioctl_ops uvc_v4l2_ioctl_ops = {
266 	.vidioc_querycap = uvc_v4l2_querycap,
267 	.vidioc_g_fmt_vid_out = uvc_v4l2_get_format,
268 	.vidioc_s_fmt_vid_out = uvc_v4l2_set_format,
269 	.vidioc_reqbufs = uvc_v4l2_reqbufs,
270 	.vidioc_querybuf = uvc_v4l2_querybuf,
271 	.vidioc_qbuf = uvc_v4l2_qbuf,
272 	.vidioc_dqbuf = uvc_v4l2_dqbuf,
273 	.vidioc_streamon = uvc_v4l2_streamon,
274 	.vidioc_streamoff = uvc_v4l2_streamoff,
275 	.vidioc_subscribe_event = uvc_v4l2_subscribe_event,
276 	.vidioc_unsubscribe_event = uvc_v4l2_unsubscribe_event,
277 	.vidioc_default = uvc_v4l2_ioctl_default,
278 };
279 
280 /* --------------------------------------------------------------------------
281  * V4L2
282  */
283 
284 static int
285 uvc_v4l2_open(struct file *file)
286 {
287 	struct video_device *vdev = video_devdata(file);
288 	struct uvc_device *uvc = video_get_drvdata(vdev);
289 	struct uvc_file_handle *handle;
290 
291 	handle = kzalloc(sizeof(*handle), GFP_KERNEL);
292 	if (handle == NULL)
293 		return -ENOMEM;
294 
295 	v4l2_fh_init(&handle->vfh, vdev);
296 	v4l2_fh_add(&handle->vfh);
297 
298 	handle->device = &uvc->video;
299 	file->private_data = &handle->vfh;
300 
301 	uvc_function_connect(uvc);
302 	return 0;
303 }
304 
305 static int
306 uvc_v4l2_release(struct file *file)
307 {
308 	struct video_device *vdev = video_devdata(file);
309 	struct uvc_device *uvc = video_get_drvdata(vdev);
310 	struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
311 	struct uvc_video *video = handle->device;
312 
313 	uvc_function_disconnect(uvc);
314 
315 	mutex_lock(&video->mutex);
316 	uvcg_video_enable(video, 0);
317 	uvcg_free_buffers(&video->queue);
318 	mutex_unlock(&video->mutex);
319 
320 	file->private_data = NULL;
321 	v4l2_fh_del(&handle->vfh);
322 	v4l2_fh_exit(&handle->vfh);
323 	kfree(handle);
324 
325 	return 0;
326 }
327 
328 static int
329 uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
330 {
331 	struct video_device *vdev = video_devdata(file);
332 	struct uvc_device *uvc = video_get_drvdata(vdev);
333 
334 	return uvcg_queue_mmap(&uvc->video.queue, vma);
335 }
336 
337 static unsigned int
338 uvc_v4l2_poll(struct file *file, poll_table *wait)
339 {
340 	struct video_device *vdev = video_devdata(file);
341 	struct uvc_device *uvc = video_get_drvdata(vdev);
342 
343 	return uvcg_queue_poll(&uvc->video.queue, file, wait);
344 }
345 
346 #ifndef CONFIG_MMU
347 static unsigned long uvcg_v4l2_get_unmapped_area(struct file *file,
348 		unsigned long addr, unsigned long len, unsigned long pgoff,
349 		unsigned long flags)
350 {
351 	struct video_device *vdev = video_devdata(file);
352 	struct uvc_device *uvc = video_get_drvdata(vdev);
353 
354 	return uvcg_queue_get_unmapped_area(&uvc->video.queue, pgoff);
355 }
356 #endif
357 
358 struct v4l2_file_operations uvc_v4l2_fops = {
359 	.owner		= THIS_MODULE,
360 	.open		= uvc_v4l2_open,
361 	.release	= uvc_v4l2_release,
362 	.unlocked_ioctl	= video_ioctl2,
363 	.mmap		= uvc_v4l2_mmap,
364 	.poll		= uvc_v4l2_poll,
365 #ifndef CONFIG_MMU
366 	.get_unmapped_area = uvcg_v4l2_get_unmapped_area,
367 #endif
368 };
369 
370