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 	return uvcg_video_pump(video);
173 }
174 
175 static int
176 uvc_v4l2_dqbuf(struct file *file, void *fh, struct v4l2_buffer *b)
177 {
178 	struct video_device *vdev = video_devdata(file);
179 	struct uvc_device *uvc = video_get_drvdata(vdev);
180 	struct uvc_video *video = &uvc->video;
181 
182 	return uvcg_dequeue_buffer(&video->queue, b, file->f_flags & O_NONBLOCK);
183 }
184 
185 static int
186 uvc_v4l2_streamon(struct file *file, void *fh, enum v4l2_buf_type type)
187 {
188 	struct video_device *vdev = video_devdata(file);
189 	struct uvc_device *uvc = video_get_drvdata(vdev);
190 	struct uvc_video *video = &uvc->video;
191 	int ret;
192 
193 	if (type != video->queue.queue.type)
194 		return -EINVAL;
195 
196 	/* Enable UVC video. */
197 	ret = uvcg_video_enable(video, 1);
198 	if (ret < 0)
199 		return ret;
200 
201 	/*
202 	 * Complete the alternate setting selection setup phase now that
203 	 * userspace is ready to provide video frames.
204 	 */
205 	uvc_function_setup_continue(uvc);
206 	uvc->state = UVC_STATE_STREAMING;
207 
208 	return 0;
209 }
210 
211 static int
212 uvc_v4l2_streamoff(struct file *file, void *fh, enum v4l2_buf_type type)
213 {
214 	struct video_device *vdev = video_devdata(file);
215 	struct uvc_device *uvc = video_get_drvdata(vdev);
216 	struct uvc_video *video = &uvc->video;
217 
218 	if (type != video->queue.queue.type)
219 		return -EINVAL;
220 
221 	return uvcg_video_enable(video, 0);
222 }
223 
224 static int
225 uvc_v4l2_subscribe_event(struct v4l2_fh *fh,
226 			 const struct v4l2_event_subscription *sub)
227 {
228 	if (sub->type < UVC_EVENT_FIRST || sub->type > UVC_EVENT_LAST)
229 		return -EINVAL;
230 
231 	return v4l2_event_subscribe(fh, sub, 2, NULL);
232 }
233 
234 static int
235 uvc_v4l2_unsubscribe_event(struct v4l2_fh *fh,
236 			   const struct v4l2_event_subscription *sub)
237 {
238 	return v4l2_event_unsubscribe(fh, sub);
239 }
240 
241 static long
242 uvc_v4l2_ioctl_default(struct file *file, void *fh, bool valid_prio,
243 		       unsigned int cmd, void *arg)
244 {
245 	struct video_device *vdev = video_devdata(file);
246 	struct uvc_device *uvc = video_get_drvdata(vdev);
247 
248 	switch (cmd) {
249 	case UVCIOC_SEND_RESPONSE:
250 		return uvc_send_response(uvc, arg);
251 
252 	default:
253 		return -ENOIOCTLCMD;
254 	}
255 }
256 
257 const struct v4l2_ioctl_ops uvc_v4l2_ioctl_ops = {
258 	.vidioc_querycap = uvc_v4l2_querycap,
259 	.vidioc_g_fmt_vid_out = uvc_v4l2_get_format,
260 	.vidioc_s_fmt_vid_out = uvc_v4l2_set_format,
261 	.vidioc_reqbufs = uvc_v4l2_reqbufs,
262 	.vidioc_querybuf = uvc_v4l2_querybuf,
263 	.vidioc_qbuf = uvc_v4l2_qbuf,
264 	.vidioc_dqbuf = uvc_v4l2_dqbuf,
265 	.vidioc_streamon = uvc_v4l2_streamon,
266 	.vidioc_streamoff = uvc_v4l2_streamoff,
267 	.vidioc_subscribe_event = uvc_v4l2_subscribe_event,
268 	.vidioc_unsubscribe_event = uvc_v4l2_unsubscribe_event,
269 	.vidioc_default = uvc_v4l2_ioctl_default,
270 };
271 
272 /* --------------------------------------------------------------------------
273  * V4L2
274  */
275 
276 static int
277 uvc_v4l2_open(struct file *file)
278 {
279 	struct video_device *vdev = video_devdata(file);
280 	struct uvc_device *uvc = video_get_drvdata(vdev);
281 	struct uvc_file_handle *handle;
282 
283 	handle = kzalloc(sizeof(*handle), GFP_KERNEL);
284 	if (handle == NULL)
285 		return -ENOMEM;
286 
287 	v4l2_fh_init(&handle->vfh, vdev);
288 	v4l2_fh_add(&handle->vfh);
289 
290 	handle->device = &uvc->video;
291 	file->private_data = &handle->vfh;
292 
293 	uvc_function_connect(uvc);
294 	return 0;
295 }
296 
297 static int
298 uvc_v4l2_release(struct file *file)
299 {
300 	struct video_device *vdev = video_devdata(file);
301 	struct uvc_device *uvc = video_get_drvdata(vdev);
302 	struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
303 	struct uvc_video *video = handle->device;
304 
305 	uvc_function_disconnect(uvc);
306 
307 	mutex_lock(&video->mutex);
308 	uvcg_video_enable(video, 0);
309 	uvcg_free_buffers(&video->queue);
310 	mutex_unlock(&video->mutex);
311 
312 	file->private_data = NULL;
313 	v4l2_fh_del(&handle->vfh);
314 	v4l2_fh_exit(&handle->vfh);
315 	kfree(handle);
316 
317 	return 0;
318 }
319 
320 static int
321 uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
322 {
323 	struct video_device *vdev = video_devdata(file);
324 	struct uvc_device *uvc = video_get_drvdata(vdev);
325 
326 	return uvcg_queue_mmap(&uvc->video.queue, vma);
327 }
328 
329 static __poll_t
330 uvc_v4l2_poll(struct file *file, poll_table *wait)
331 {
332 	struct video_device *vdev = video_devdata(file);
333 	struct uvc_device *uvc = video_get_drvdata(vdev);
334 
335 	return uvcg_queue_poll(&uvc->video.queue, file, wait);
336 }
337 
338 #ifndef CONFIG_MMU
339 static unsigned long uvcg_v4l2_get_unmapped_area(struct file *file,
340 		unsigned long addr, unsigned long len, unsigned long pgoff,
341 		unsigned long flags)
342 {
343 	struct video_device *vdev = video_devdata(file);
344 	struct uvc_device *uvc = video_get_drvdata(vdev);
345 
346 	return uvcg_queue_get_unmapped_area(&uvc->video.queue, pgoff);
347 }
348 #endif
349 
350 const struct v4l2_file_operations uvc_v4l2_fops = {
351 	.owner		= THIS_MODULE,
352 	.open		= uvc_v4l2_open,
353 	.release	= uvc_v4l2_release,
354 	.unlocked_ioctl	= video_ioctl2,
355 	.mmap		= uvc_v4l2_mmap,
356 	.poll		= uvc_v4l2_poll,
357 #ifndef CONFIG_MMU
358 	.get_unmapped_area = uvcg_v4l2_get_unmapped_area,
359 #endif
360 };
361 
362