1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *	uvc_v4l2.c  --  USB Video Class Gadget driver
4  *
5  *	Copyright (C) 2009-2010
6  *	    Laurent Pinchart (laurent.pinchart@ideasonboard.com)
7  */
8 
9 #include <linux/device.h>
10 #include <linux/errno.h>
11 #include <linux/kernel.h>
12 #include <linux/list.h>
13 #include <linux/usb/g_uvc.h>
14 #include <linux/videodev2.h>
15 #include <linux/vmalloc.h>
16 #include <linux/wait.h>
17 
18 #include <media/v4l2-dev.h>
19 #include <media/v4l2-event.h>
20 #include <media/v4l2-ioctl.h>
21 
22 #include "f_uvc.h"
23 #include "uvc.h"
24 #include "uvc_queue.h"
25 #include "uvc_video.h"
26 #include "uvc_v4l2.h"
27 
28 /* --------------------------------------------------------------------------
29  * Requests handling
30  */
31 
32 static int
33 uvc_send_response(struct uvc_device *uvc, struct uvc_request_data *data)
34 {
35 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
36 	struct usb_request *req = uvc->control_req;
37 
38 	if (data->length < 0)
39 		return usb_ep_set_halt(cdev->gadget->ep0);
40 
41 	req->length = min_t(unsigned int, uvc->event_length, data->length);
42 	req->zero = data->length < uvc->event_length;
43 
44 	memcpy(req->buf, data->data, req->length);
45 
46 	return usb_ep_queue(cdev->gadget->ep0, req, GFP_KERNEL);
47 }
48 
49 /* --------------------------------------------------------------------------
50  * V4L2 ioctls
51  */
52 
53 struct uvc_format {
54 	u8 bpp;
55 	u32 fcc;
56 };
57 
58 static struct uvc_format uvc_formats[] = {
59 	{ 16, V4L2_PIX_FMT_YUYV  },
60 	{ 0,  V4L2_PIX_FMT_MJPEG },
61 };
62 
63 static int
64 uvc_v4l2_querycap(struct file *file, void *fh, struct v4l2_capability *cap)
65 {
66 	struct video_device *vdev = video_devdata(file);
67 	struct uvc_device *uvc = video_get_drvdata(vdev);
68 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
69 
70 	strlcpy(cap->driver, "g_uvc", sizeof(cap->driver));
71 	strlcpy(cap->card, cdev->gadget->name, sizeof(cap->card));
72 	strlcpy(cap->bus_info, dev_name(&cdev->gadget->dev),
73 		sizeof(cap->bus_info));
74 	return 0;
75 }
76 
77 static int
78 uvc_v4l2_get_format(struct file *file, void *fh, struct v4l2_format *fmt)
79 {
80 	struct video_device *vdev = video_devdata(file);
81 	struct uvc_device *uvc = video_get_drvdata(vdev);
82 	struct uvc_video *video = &uvc->video;
83 
84 	fmt->fmt.pix.pixelformat = video->fcc;
85 	fmt->fmt.pix.width = video->width;
86 	fmt->fmt.pix.height = video->height;
87 	fmt->fmt.pix.field = V4L2_FIELD_NONE;
88 	fmt->fmt.pix.bytesperline = video->bpp * video->width / 8;
89 	fmt->fmt.pix.sizeimage = video->imagesize;
90 	fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
91 	fmt->fmt.pix.priv = 0;
92 
93 	return 0;
94 }
95 
96 static int
97 uvc_v4l2_set_format(struct file *file, void *fh, struct v4l2_format *fmt)
98 {
99 	struct video_device *vdev = video_devdata(file);
100 	struct uvc_device *uvc = video_get_drvdata(vdev);
101 	struct uvc_video *video = &uvc->video;
102 	struct uvc_format *format;
103 	unsigned int imagesize;
104 	unsigned int bpl;
105 	unsigned int i;
106 
107 	for (i = 0; i < ARRAY_SIZE(uvc_formats); ++i) {
108 		format = &uvc_formats[i];
109 		if (format->fcc == fmt->fmt.pix.pixelformat)
110 			break;
111 	}
112 
113 	if (i == ARRAY_SIZE(uvc_formats)) {
114 		uvcg_info(&uvc->func, "Unsupported format 0x%08x.\n",
115 			  fmt->fmt.pix.pixelformat);
116 		return -EINVAL;
117 	}
118 
119 	bpl = format->bpp * fmt->fmt.pix.width / 8;
120 	imagesize = bpl ? bpl * fmt->fmt.pix.height : fmt->fmt.pix.sizeimage;
121 
122 	video->fcc = format->fcc;
123 	video->bpp = format->bpp;
124 	video->width = fmt->fmt.pix.width;
125 	video->height = fmt->fmt.pix.height;
126 	video->imagesize = imagesize;
127 
128 	fmt->fmt.pix.field = V4L2_FIELD_NONE;
129 	fmt->fmt.pix.bytesperline = bpl;
130 	fmt->fmt.pix.sizeimage = imagesize;
131 	fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
132 	fmt->fmt.pix.priv = 0;
133 
134 	return 0;
135 }
136 
137 static int
138 uvc_v4l2_reqbufs(struct file *file, void *fh, struct v4l2_requestbuffers *b)
139 {
140 	struct video_device *vdev = video_devdata(file);
141 	struct uvc_device *uvc = video_get_drvdata(vdev);
142 	struct uvc_video *video = &uvc->video;
143 
144 	if (b->type != video->queue.queue.type)
145 		return -EINVAL;
146 
147 	return uvcg_alloc_buffers(&video->queue, b);
148 }
149 
150 static int
151 uvc_v4l2_querybuf(struct file *file, void *fh, struct v4l2_buffer *b)
152 {
153 	struct video_device *vdev = video_devdata(file);
154 	struct uvc_device *uvc = video_get_drvdata(vdev);
155 	struct uvc_video *video = &uvc->video;
156 
157 	return uvcg_query_buffer(&video->queue, b);
158 }
159 
160 static int
161 uvc_v4l2_qbuf(struct file *file, void *fh, struct v4l2_buffer *b)
162 {
163 	struct video_device *vdev = video_devdata(file);
164 	struct uvc_device *uvc = video_get_drvdata(vdev);
165 	struct uvc_video *video = &uvc->video;
166 	int ret;
167 
168 	ret = uvcg_queue_buffer(&video->queue, b);
169 	if (ret < 0)
170 		return ret;
171 
172 	if (uvc->state == UVC_STATE_STREAMING)
173 		schedule_work(&video->pump);
174 
175 	return ret;
176 }
177 
178 static int
179 uvc_v4l2_dqbuf(struct file *file, void *fh, struct v4l2_buffer *b)
180 {
181 	struct video_device *vdev = video_devdata(file);
182 	struct uvc_device *uvc = video_get_drvdata(vdev);
183 	struct uvc_video *video = &uvc->video;
184 
185 	return uvcg_dequeue_buffer(&video->queue, b, file->f_flags & O_NONBLOCK);
186 }
187 
188 static int
189 uvc_v4l2_streamon(struct file *file, void *fh, enum v4l2_buf_type type)
190 {
191 	struct video_device *vdev = video_devdata(file);
192 	struct uvc_device *uvc = video_get_drvdata(vdev);
193 	struct uvc_video *video = &uvc->video;
194 	int ret;
195 
196 	if (type != video->queue.queue.type)
197 		return -EINVAL;
198 
199 	/* Enable UVC video. */
200 	ret = uvcg_video_enable(video, 1);
201 	if (ret < 0)
202 		return ret;
203 
204 	/*
205 	 * Complete the alternate setting selection setup phase now that
206 	 * userspace is ready to provide video frames.
207 	 */
208 	uvc_function_setup_continue(uvc);
209 	uvc->state = UVC_STATE_STREAMING;
210 
211 	return 0;
212 }
213 
214 static int
215 uvc_v4l2_streamoff(struct file *file, void *fh, enum v4l2_buf_type type)
216 {
217 	struct video_device *vdev = video_devdata(file);
218 	struct uvc_device *uvc = video_get_drvdata(vdev);
219 	struct uvc_video *video = &uvc->video;
220 
221 	if (type != video->queue.queue.type)
222 		return -EINVAL;
223 
224 	return uvcg_video_enable(video, 0);
225 }
226 
227 static int
228 uvc_v4l2_subscribe_event(struct v4l2_fh *fh,
229 			 const struct v4l2_event_subscription *sub)
230 {
231 	struct uvc_device *uvc = video_get_drvdata(fh->vdev);
232 	struct uvc_file_handle *handle = to_uvc_file_handle(fh);
233 	int ret;
234 
235 	if (sub->type < UVC_EVENT_FIRST || sub->type > UVC_EVENT_LAST)
236 		return -EINVAL;
237 
238 	if (sub->type == UVC_EVENT_SETUP && uvc->func_connected)
239 		return -EBUSY;
240 
241 	ret = v4l2_event_subscribe(fh, sub, 2, NULL);
242 	if (ret < 0)
243 		return ret;
244 
245 	if (sub->type == UVC_EVENT_SETUP) {
246 		uvc->func_connected = true;
247 		handle->is_uvc_app_handle = true;
248 		uvc_function_connect(uvc);
249 	}
250 
251 	return 0;
252 }
253 
254 static void uvc_v4l2_disable(struct uvc_device *uvc)
255 {
256 	uvc_function_disconnect(uvc);
257 	uvcg_video_enable(&uvc->video, 0);
258 	uvcg_free_buffers(&uvc->video.queue);
259 	uvc->func_connected = false;
260 	wake_up_interruptible(&uvc->func_connected_queue);
261 }
262 
263 static int
264 uvc_v4l2_unsubscribe_event(struct v4l2_fh *fh,
265 			   const struct v4l2_event_subscription *sub)
266 {
267 	struct uvc_device *uvc = video_get_drvdata(fh->vdev);
268 	struct uvc_file_handle *handle = to_uvc_file_handle(fh);
269 	int ret;
270 
271 	ret = v4l2_event_unsubscribe(fh, sub);
272 	if (ret < 0)
273 		return ret;
274 
275 	if (sub->type == UVC_EVENT_SETUP && handle->is_uvc_app_handle) {
276 		uvc_v4l2_disable(uvc);
277 		handle->is_uvc_app_handle = false;
278 	}
279 
280 	return 0;
281 }
282 
283 static long
284 uvc_v4l2_ioctl_default(struct file *file, void *fh, bool valid_prio,
285 		       unsigned int cmd, void *arg)
286 {
287 	struct video_device *vdev = video_devdata(file);
288 	struct uvc_device *uvc = video_get_drvdata(vdev);
289 
290 	switch (cmd) {
291 	case UVCIOC_SEND_RESPONSE:
292 		return uvc_send_response(uvc, arg);
293 
294 	default:
295 		return -ENOIOCTLCMD;
296 	}
297 }
298 
299 const struct v4l2_ioctl_ops uvc_v4l2_ioctl_ops = {
300 	.vidioc_querycap = uvc_v4l2_querycap,
301 	.vidioc_g_fmt_vid_out = uvc_v4l2_get_format,
302 	.vidioc_s_fmt_vid_out = uvc_v4l2_set_format,
303 	.vidioc_reqbufs = uvc_v4l2_reqbufs,
304 	.vidioc_querybuf = uvc_v4l2_querybuf,
305 	.vidioc_qbuf = uvc_v4l2_qbuf,
306 	.vidioc_dqbuf = uvc_v4l2_dqbuf,
307 	.vidioc_streamon = uvc_v4l2_streamon,
308 	.vidioc_streamoff = uvc_v4l2_streamoff,
309 	.vidioc_subscribe_event = uvc_v4l2_subscribe_event,
310 	.vidioc_unsubscribe_event = uvc_v4l2_unsubscribe_event,
311 	.vidioc_default = uvc_v4l2_ioctl_default,
312 };
313 
314 /* --------------------------------------------------------------------------
315  * V4L2
316  */
317 
318 static int
319 uvc_v4l2_open(struct file *file)
320 {
321 	struct video_device *vdev = video_devdata(file);
322 	struct uvc_device *uvc = video_get_drvdata(vdev);
323 	struct uvc_file_handle *handle;
324 
325 	handle = kzalloc(sizeof(*handle), GFP_KERNEL);
326 	if (handle == NULL)
327 		return -ENOMEM;
328 
329 	v4l2_fh_init(&handle->vfh, vdev);
330 	v4l2_fh_add(&handle->vfh);
331 
332 	handle->device = &uvc->video;
333 	file->private_data = &handle->vfh;
334 
335 	return 0;
336 }
337 
338 static int
339 uvc_v4l2_release(struct file *file)
340 {
341 	struct video_device *vdev = video_devdata(file);
342 	struct uvc_device *uvc = video_get_drvdata(vdev);
343 	struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
344 	struct uvc_video *video = handle->device;
345 
346 	mutex_lock(&video->mutex);
347 	if (handle->is_uvc_app_handle)
348 		uvc_v4l2_disable(uvc);
349 	mutex_unlock(&video->mutex);
350 
351 	file->private_data = NULL;
352 	v4l2_fh_del(&handle->vfh);
353 	v4l2_fh_exit(&handle->vfh);
354 	kfree(handle);
355 
356 	return 0;
357 }
358 
359 static int
360 uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
361 {
362 	struct video_device *vdev = video_devdata(file);
363 	struct uvc_device *uvc = video_get_drvdata(vdev);
364 
365 	return uvcg_queue_mmap(&uvc->video.queue, vma);
366 }
367 
368 static __poll_t
369 uvc_v4l2_poll(struct file *file, poll_table *wait)
370 {
371 	struct video_device *vdev = video_devdata(file);
372 	struct uvc_device *uvc = video_get_drvdata(vdev);
373 
374 	return uvcg_queue_poll(&uvc->video.queue, file, wait);
375 }
376 
377 #ifndef CONFIG_MMU
378 static unsigned long uvcg_v4l2_get_unmapped_area(struct file *file,
379 		unsigned long addr, unsigned long len, unsigned long pgoff,
380 		unsigned long flags)
381 {
382 	struct video_device *vdev = video_devdata(file);
383 	struct uvc_device *uvc = video_get_drvdata(vdev);
384 
385 	return uvcg_queue_get_unmapped_area(&uvc->video.queue, pgoff);
386 }
387 #endif
388 
389 const struct v4l2_file_operations uvc_v4l2_fops = {
390 	.owner		= THIS_MODULE,
391 	.open		= uvc_v4l2_open,
392 	.release	= uvc_v4l2_release,
393 	.unlocked_ioctl	= video_ioctl2,
394 	.mmap		= uvc_v4l2_mmap,
395 	.poll		= uvc_v4l2_poll,
396 #ifndef CONFIG_MMU
397 	.get_unmapped_area = uvcg_v4l2_get_unmapped_area,
398 #endif
399 };
400 
401