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/kernel.h>
10 #include <linux/device.h>
11 #include <linux/errno.h>
12 #include <linux/list.h>
13 #include <linux/videodev2.h>
14 #include <linux/vmalloc.h>
15 #include <linux/wait.h>
16 
17 #include <media/v4l2-dev.h>
18 #include <media/v4l2-event.h>
19 #include <media/v4l2-ioctl.h>
20 
21 #include "f_uvc.h"
22 #include "uvc.h"
23 #include "uvc_queue.h"
24 #include "uvc_video.h"
25 #include "uvc_v4l2.h"
26 
27 /* --------------------------------------------------------------------------
28  * Requests handling
29  */
30 
31 static int
32 uvc_send_response(struct uvc_device *uvc, struct uvc_request_data *data)
33 {
34 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
35 	struct usb_request *req = uvc->control_req;
36 
37 	if (data->length < 0)
38 		return usb_ep_set_halt(cdev->gadget->ep0);
39 
40 	req->length = min_t(unsigned int, uvc->event_length, data->length);
41 	req->zero = data->length < uvc->event_length;
42 
43 	memcpy(req->buf, data->data, req->length);
44 
45 	return usb_ep_queue(cdev->gadget->ep0, req, GFP_KERNEL);
46 }
47 
48 /* --------------------------------------------------------------------------
49  * V4L2 ioctls
50  */
51 
52 struct uvc_format {
53 	u8 bpp;
54 	u32 fcc;
55 };
56 
57 static struct uvc_format uvc_formats[] = {
58 	{ 16, V4L2_PIX_FMT_YUYV  },
59 	{ 0,  V4L2_PIX_FMT_MJPEG },
60 };
61 
62 static int
63 uvc_v4l2_querycap(struct file *file, void *fh, struct v4l2_capability *cap)
64 {
65 	struct video_device *vdev = video_devdata(file);
66 	struct uvc_device *uvc = video_get_drvdata(vdev);
67 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
68 
69 	strlcpy(cap->driver, "g_uvc", sizeof(cap->driver));
70 	strlcpy(cap->card, cdev->gadget->name, sizeof(cap->card));
71 	strlcpy(cap->bus_info, dev_name(&cdev->gadget->dev),
72 		sizeof(cap->bus_info));
73 
74 	cap->device_caps = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
75 	cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
76 
77 	return 0;
78 }
79 
80 static int
81 uvc_v4l2_get_format(struct file *file, void *fh, struct v4l2_format *fmt)
82 {
83 	struct video_device *vdev = video_devdata(file);
84 	struct uvc_device *uvc = video_get_drvdata(vdev);
85 	struct uvc_video *video = &uvc->video;
86 
87 	fmt->fmt.pix.pixelformat = video->fcc;
88 	fmt->fmt.pix.width = video->width;
89 	fmt->fmt.pix.height = video->height;
90 	fmt->fmt.pix.field = V4L2_FIELD_NONE;
91 	fmt->fmt.pix.bytesperline = video->bpp * video->width / 8;
92 	fmt->fmt.pix.sizeimage = video->imagesize;
93 	fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
94 	fmt->fmt.pix.priv = 0;
95 
96 	return 0;
97 }
98 
99 static int
100 uvc_v4l2_set_format(struct file *file, void *fh, struct v4l2_format *fmt)
101 {
102 	struct video_device *vdev = video_devdata(file);
103 	struct uvc_device *uvc = video_get_drvdata(vdev);
104 	struct uvc_video *video = &uvc->video;
105 	struct uvc_format *format;
106 	unsigned int imagesize;
107 	unsigned int bpl;
108 	unsigned int i;
109 
110 	for (i = 0; i < ARRAY_SIZE(uvc_formats); ++i) {
111 		format = &uvc_formats[i];
112 		if (format->fcc == fmt->fmt.pix.pixelformat)
113 			break;
114 	}
115 
116 	if (i == ARRAY_SIZE(uvc_formats)) {
117 		printk(KERN_INFO "Unsupported format 0x%08x.\n",
118 			fmt->fmt.pix.pixelformat);
119 		return -EINVAL;
120 	}
121 
122 	bpl = format->bpp * fmt->fmt.pix.width / 8;
123 	imagesize = bpl ? bpl * fmt->fmt.pix.height : fmt->fmt.pix.sizeimage;
124 
125 	video->fcc = format->fcc;
126 	video->bpp = format->bpp;
127 	video->width = fmt->fmt.pix.width;
128 	video->height = fmt->fmt.pix.height;
129 	video->imagesize = imagesize;
130 
131 	fmt->fmt.pix.field = V4L2_FIELD_NONE;
132 	fmt->fmt.pix.bytesperline = bpl;
133 	fmt->fmt.pix.sizeimage = imagesize;
134 	fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
135 	fmt->fmt.pix.priv = 0;
136 
137 	return 0;
138 }
139 
140 static int
141 uvc_v4l2_reqbufs(struct file *file, void *fh, struct v4l2_requestbuffers *b)
142 {
143 	struct video_device *vdev = video_devdata(file);
144 	struct uvc_device *uvc = video_get_drvdata(vdev);
145 	struct uvc_video *video = &uvc->video;
146 
147 	if (b->type != video->queue.queue.type)
148 		return -EINVAL;
149 
150 	return uvcg_alloc_buffers(&video->queue, b);
151 }
152 
153 static int
154 uvc_v4l2_querybuf(struct file *file, void *fh, struct v4l2_buffer *b)
155 {
156 	struct video_device *vdev = video_devdata(file);
157 	struct uvc_device *uvc = video_get_drvdata(vdev);
158 	struct uvc_video *video = &uvc->video;
159 
160 	return uvcg_query_buffer(&video->queue, b);
161 }
162 
163 static int
164 uvc_v4l2_qbuf(struct file *file, void *fh, struct v4l2_buffer *b)
165 {
166 	struct video_device *vdev = video_devdata(file);
167 	struct uvc_device *uvc = video_get_drvdata(vdev);
168 	struct uvc_video *video = &uvc->video;
169 	int ret;
170 
171 	ret = uvcg_queue_buffer(&video->queue, b);
172 	if (ret < 0)
173 		return ret;
174 
175 	return uvcg_video_pump(video);
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 	if (sub->type < UVC_EVENT_FIRST || sub->type > UVC_EVENT_LAST)
232 		return -EINVAL;
233 
234 	return v4l2_event_subscribe(fh, sub, 2, NULL);
235 }
236 
237 static int
238 uvc_v4l2_unsubscribe_event(struct v4l2_fh *fh,
239 			   const struct v4l2_event_subscription *sub)
240 {
241 	return v4l2_event_unsubscribe(fh, sub);
242 }
243 
244 static long
245 uvc_v4l2_ioctl_default(struct file *file, void *fh, bool valid_prio,
246 		       unsigned int cmd, void *arg)
247 {
248 	struct video_device *vdev = video_devdata(file);
249 	struct uvc_device *uvc = video_get_drvdata(vdev);
250 
251 	switch (cmd) {
252 	case UVCIOC_SEND_RESPONSE:
253 		return uvc_send_response(uvc, arg);
254 
255 	default:
256 		return -ENOIOCTLCMD;
257 	}
258 }
259 
260 const struct v4l2_ioctl_ops uvc_v4l2_ioctl_ops = {
261 	.vidioc_querycap = uvc_v4l2_querycap,
262 	.vidioc_g_fmt_vid_out = uvc_v4l2_get_format,
263 	.vidioc_s_fmt_vid_out = uvc_v4l2_set_format,
264 	.vidioc_reqbufs = uvc_v4l2_reqbufs,
265 	.vidioc_querybuf = uvc_v4l2_querybuf,
266 	.vidioc_qbuf = uvc_v4l2_qbuf,
267 	.vidioc_dqbuf = uvc_v4l2_dqbuf,
268 	.vidioc_streamon = uvc_v4l2_streamon,
269 	.vidioc_streamoff = uvc_v4l2_streamoff,
270 	.vidioc_subscribe_event = uvc_v4l2_subscribe_event,
271 	.vidioc_unsubscribe_event = uvc_v4l2_unsubscribe_event,
272 	.vidioc_default = uvc_v4l2_ioctl_default,
273 };
274 
275 /* --------------------------------------------------------------------------
276  * V4L2
277  */
278 
279 static int
280 uvc_v4l2_open(struct file *file)
281 {
282 	struct video_device *vdev = video_devdata(file);
283 	struct uvc_device *uvc = video_get_drvdata(vdev);
284 	struct uvc_file_handle *handle;
285 
286 	handle = kzalloc(sizeof(*handle), GFP_KERNEL);
287 	if (handle == NULL)
288 		return -ENOMEM;
289 
290 	v4l2_fh_init(&handle->vfh, vdev);
291 	v4l2_fh_add(&handle->vfh);
292 
293 	handle->device = &uvc->video;
294 	file->private_data = &handle->vfh;
295 
296 	uvc_function_connect(uvc);
297 	return 0;
298 }
299 
300 static int
301 uvc_v4l2_release(struct file *file)
302 {
303 	struct video_device *vdev = video_devdata(file);
304 	struct uvc_device *uvc = video_get_drvdata(vdev);
305 	struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
306 	struct uvc_video *video = handle->device;
307 
308 	uvc_function_disconnect(uvc);
309 
310 	mutex_lock(&video->mutex);
311 	uvcg_video_enable(video, 0);
312 	uvcg_free_buffers(&video->queue);
313 	mutex_unlock(&video->mutex);
314 
315 	file->private_data = NULL;
316 	v4l2_fh_del(&handle->vfh);
317 	v4l2_fh_exit(&handle->vfh);
318 	kfree(handle);
319 
320 	return 0;
321 }
322 
323 static int
324 uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
325 {
326 	struct video_device *vdev = video_devdata(file);
327 	struct uvc_device *uvc = video_get_drvdata(vdev);
328 
329 	return uvcg_queue_mmap(&uvc->video.queue, vma);
330 }
331 
332 static __poll_t
333 uvc_v4l2_poll(struct file *file, poll_table *wait)
334 {
335 	struct video_device *vdev = video_devdata(file);
336 	struct uvc_device *uvc = video_get_drvdata(vdev);
337 
338 	return uvcg_queue_poll(&uvc->video.queue, file, wait);
339 }
340 
341 #ifndef CONFIG_MMU
342 static unsigned long uvcg_v4l2_get_unmapped_area(struct file *file,
343 		unsigned long addr, unsigned long len, unsigned long pgoff,
344 		unsigned long flags)
345 {
346 	struct video_device *vdev = video_devdata(file);
347 	struct uvc_device *uvc = video_get_drvdata(vdev);
348 
349 	return uvcg_queue_get_unmapped_area(&uvc->video.queue, pgoff);
350 }
351 #endif
352 
353 const struct v4l2_file_operations uvc_v4l2_fops = {
354 	.owner		= THIS_MODULE,
355 	.open		= uvc_v4l2_open,
356 	.release	= uvc_v4l2_release,
357 	.unlocked_ioctl	= video_ioctl2,
358 	.mmap		= uvc_v4l2_mmap,
359 	.poll		= uvc_v4l2_poll,
360 #ifndef CONFIG_MMU
361 	.get_unmapped_area = uvcg_v4l2_get_unmapped_area,
362 #endif
363 };
364 
365