1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * uvc_gadget.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/fs.h>
12 #include <linux/kernel.h>
13 #include <linux/list.h>
14 #include <linux/module.h>
15 #include <linux/mutex.h>
16 #include <linux/string.h>
17 #include <linux/usb/ch9.h>
18 #include <linux/usb/gadget.h>
19 #include <linux/usb/g_uvc.h>
20 #include <linux/usb/video.h>
21 #include <linux/vmalloc.h>
22 #include <linux/wait.h>
23
24 #include <media/v4l2-dev.h>
25 #include <media/v4l2-event.h>
26
27 #include "uvc.h"
28 #include "uvc_configfs.h"
29 #include "uvc_v4l2.h"
30 #include "uvc_video.h"
31
32 unsigned int uvc_gadget_trace_param;
33 module_param_named(trace, uvc_gadget_trace_param, uint, 0644);
34 MODULE_PARM_DESC(trace, "Trace level bitmask");
35
36 /* --------------------------------------------------------------------------
37 * Function descriptors
38 */
39
40 /* string IDs are assigned dynamically */
41
42 static struct usb_string uvc_en_us_strings[] = {
43 /* [UVC_STRING_CONTROL_IDX].s = DYNAMIC, */
44 [UVC_STRING_STREAMING_IDX].s = "Video Streaming",
45 { }
46 };
47
48 static struct usb_gadget_strings uvc_stringtab = {
49 .language = 0x0409, /* en-us */
50 .strings = uvc_en_us_strings,
51 };
52
53 static struct usb_gadget_strings *uvc_function_strings[] = {
54 &uvc_stringtab,
55 NULL,
56 };
57
58 #define UVC_INTF_VIDEO_CONTROL 0
59 #define UVC_INTF_VIDEO_STREAMING 1
60
61 #define UVC_STATUS_MAX_PACKET_SIZE 16 /* 16 bytes status */
62
63 static struct usb_interface_assoc_descriptor uvc_iad = {
64 .bLength = sizeof(uvc_iad),
65 .bDescriptorType = USB_DT_INTERFACE_ASSOCIATION,
66 .bFirstInterface = 0,
67 .bInterfaceCount = 2,
68 .bFunctionClass = USB_CLASS_VIDEO,
69 .bFunctionSubClass = UVC_SC_VIDEO_INTERFACE_COLLECTION,
70 .bFunctionProtocol = 0x00,
71 .iFunction = 0,
72 };
73
74 static struct usb_interface_descriptor uvc_control_intf = {
75 .bLength = USB_DT_INTERFACE_SIZE,
76 .bDescriptorType = USB_DT_INTERFACE,
77 .bInterfaceNumber = UVC_INTF_VIDEO_CONTROL,
78 .bAlternateSetting = 0,
79 .bNumEndpoints = 0,
80 .bInterfaceClass = USB_CLASS_VIDEO,
81 .bInterfaceSubClass = UVC_SC_VIDEOCONTROL,
82 .bInterfaceProtocol = 0x00,
83 .iInterface = 0,
84 };
85
86 static struct usb_endpoint_descriptor uvc_interrupt_ep = {
87 .bLength = USB_DT_ENDPOINT_SIZE,
88 .bDescriptorType = USB_DT_ENDPOINT,
89 .bEndpointAddress = USB_DIR_IN,
90 .bmAttributes = USB_ENDPOINT_XFER_INT,
91 .wMaxPacketSize = cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
92 .bInterval = 8,
93 };
94
95 static struct usb_ss_ep_comp_descriptor uvc_ss_interrupt_comp = {
96 .bLength = sizeof(uvc_ss_interrupt_comp),
97 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
98 /* The following 3 values can be tweaked if necessary. */
99 .bMaxBurst = 0,
100 .bmAttributes = 0,
101 .wBytesPerInterval = cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
102 };
103
104 static struct uvc_control_endpoint_descriptor uvc_interrupt_cs_ep = {
105 .bLength = UVC_DT_CONTROL_ENDPOINT_SIZE,
106 .bDescriptorType = USB_DT_CS_ENDPOINT,
107 .bDescriptorSubType = UVC_EP_INTERRUPT,
108 .wMaxTransferSize = cpu_to_le16(UVC_STATUS_MAX_PACKET_SIZE),
109 };
110
111 static struct usb_interface_descriptor uvc_streaming_intf_alt0 = {
112 .bLength = USB_DT_INTERFACE_SIZE,
113 .bDescriptorType = USB_DT_INTERFACE,
114 .bInterfaceNumber = UVC_INTF_VIDEO_STREAMING,
115 .bAlternateSetting = 0,
116 .bNumEndpoints = 0,
117 .bInterfaceClass = USB_CLASS_VIDEO,
118 .bInterfaceSubClass = UVC_SC_VIDEOSTREAMING,
119 .bInterfaceProtocol = 0x00,
120 .iInterface = 0,
121 };
122
123 static struct usb_interface_descriptor uvc_streaming_intf_alt1 = {
124 .bLength = USB_DT_INTERFACE_SIZE,
125 .bDescriptorType = USB_DT_INTERFACE,
126 .bInterfaceNumber = UVC_INTF_VIDEO_STREAMING,
127 .bAlternateSetting = 1,
128 .bNumEndpoints = 1,
129 .bInterfaceClass = USB_CLASS_VIDEO,
130 .bInterfaceSubClass = UVC_SC_VIDEOSTREAMING,
131 .bInterfaceProtocol = 0x00,
132 .iInterface = 0,
133 };
134
135 static struct usb_endpoint_descriptor uvc_fs_streaming_ep = {
136 .bLength = USB_DT_ENDPOINT_SIZE,
137 .bDescriptorType = USB_DT_ENDPOINT,
138 .bEndpointAddress = USB_DIR_IN,
139 .bmAttributes = USB_ENDPOINT_SYNC_ASYNC
140 | USB_ENDPOINT_XFER_ISOC,
141 /*
142 * The wMaxPacketSize and bInterval values will be initialized from
143 * module parameters.
144 */
145 };
146
147 static struct usb_endpoint_descriptor uvc_hs_streaming_ep = {
148 .bLength = USB_DT_ENDPOINT_SIZE,
149 .bDescriptorType = USB_DT_ENDPOINT,
150 .bEndpointAddress = USB_DIR_IN,
151 .bmAttributes = USB_ENDPOINT_SYNC_ASYNC
152 | USB_ENDPOINT_XFER_ISOC,
153 /*
154 * The wMaxPacketSize and bInterval values will be initialized from
155 * module parameters.
156 */
157 };
158
159 static struct usb_endpoint_descriptor uvc_ss_streaming_ep = {
160 .bLength = USB_DT_ENDPOINT_SIZE,
161 .bDescriptorType = USB_DT_ENDPOINT,
162
163 .bEndpointAddress = USB_DIR_IN,
164 .bmAttributes = USB_ENDPOINT_SYNC_ASYNC
165 | USB_ENDPOINT_XFER_ISOC,
166 /*
167 * The wMaxPacketSize and bInterval values will be initialized from
168 * module parameters.
169 */
170 };
171
172 static struct usb_ss_ep_comp_descriptor uvc_ss_streaming_comp = {
173 .bLength = sizeof(uvc_ss_streaming_comp),
174 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
175 /*
176 * The bMaxBurst, bmAttributes and wBytesPerInterval values will be
177 * initialized from module parameters.
178 */
179 };
180
181 static const struct usb_descriptor_header * const uvc_fs_streaming[] = {
182 (struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
183 (struct usb_descriptor_header *) &uvc_fs_streaming_ep,
184 NULL,
185 };
186
187 static const struct usb_descriptor_header * const uvc_hs_streaming[] = {
188 (struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
189 (struct usb_descriptor_header *) &uvc_hs_streaming_ep,
190 NULL,
191 };
192
193 static const struct usb_descriptor_header * const uvc_ss_streaming[] = {
194 (struct usb_descriptor_header *) &uvc_streaming_intf_alt1,
195 (struct usb_descriptor_header *) &uvc_ss_streaming_ep,
196 (struct usb_descriptor_header *) &uvc_ss_streaming_comp,
197 NULL,
198 };
199
200 /* --------------------------------------------------------------------------
201 * Control requests
202 */
203
204 static void
uvc_function_ep0_complete(struct usb_ep * ep,struct usb_request * req)205 uvc_function_ep0_complete(struct usb_ep *ep, struct usb_request *req)
206 {
207 struct uvc_device *uvc = req->context;
208 struct v4l2_event v4l2_event;
209 struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
210
211 if (uvc->event_setup_out) {
212 uvc->event_setup_out = 0;
213
214 memset(&v4l2_event, 0, sizeof(v4l2_event));
215 v4l2_event.type = UVC_EVENT_DATA;
216 uvc_event->data.length = min_t(unsigned int, req->actual,
217 sizeof(uvc_event->data.data));
218 memcpy(&uvc_event->data.data, req->buf, uvc_event->data.length);
219 v4l2_event_queue(&uvc->vdev, &v4l2_event);
220 }
221 }
222
223 static int
uvc_function_setup(struct usb_function * f,const struct usb_ctrlrequest * ctrl)224 uvc_function_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
225 {
226 struct uvc_device *uvc = to_uvc(f);
227 struct v4l2_event v4l2_event;
228 struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
229 unsigned int interface = le16_to_cpu(ctrl->wIndex) & 0xff;
230 struct usb_ctrlrequest *mctrl;
231
232 if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS) {
233 uvcg_info(f, "invalid request type\n");
234 return -EINVAL;
235 }
236
237 /* Stall too big requests. */
238 if (le16_to_cpu(ctrl->wLength) > UVC_MAX_REQUEST_SIZE)
239 return -EINVAL;
240
241 /*
242 * Tell the complete callback to generate an event for the next request
243 * that will be enqueued by UVCIOC_SEND_RESPONSE.
244 */
245 uvc->event_setup_out = !(ctrl->bRequestType & USB_DIR_IN);
246 uvc->event_length = le16_to_cpu(ctrl->wLength);
247
248 memset(&v4l2_event, 0, sizeof(v4l2_event));
249 v4l2_event.type = UVC_EVENT_SETUP;
250 memcpy(&uvc_event->req, ctrl, sizeof(uvc_event->req));
251
252 /* check for the interface number, fixup the interface number in
253 * the ctrl request so the userspace doesn't have to bother with
254 * offset and configfs parsing
255 */
256 mctrl = &uvc_event->req;
257 mctrl->wIndex &= ~cpu_to_le16(0xff);
258 if (interface == uvc->streaming_intf)
259 mctrl->wIndex = cpu_to_le16(UVC_STRING_STREAMING_IDX);
260
261 v4l2_event_queue(&uvc->vdev, &v4l2_event);
262
263 return 0;
264 }
265
uvc_function_setup_continue(struct uvc_device * uvc,int disable_ep)266 void uvc_function_setup_continue(struct uvc_device *uvc, int disable_ep)
267 {
268 struct usb_composite_dev *cdev = uvc->func.config->cdev;
269
270 if (disable_ep && uvc->video.ep)
271 usb_ep_disable(uvc->video.ep);
272
273 usb_composite_setup_continue(cdev);
274 }
275
276 static int
uvc_function_get_alt(struct usb_function * f,unsigned interface)277 uvc_function_get_alt(struct usb_function *f, unsigned interface)
278 {
279 struct uvc_device *uvc = to_uvc(f);
280
281 uvcg_info(f, "%s(%u)\n", __func__, interface);
282
283 if (interface == uvc->control_intf)
284 return 0;
285 else if (interface != uvc->streaming_intf)
286 return -EINVAL;
287 else
288 return uvc->video.ep->enabled ? 1 : 0;
289 }
290
291 static int
uvc_function_set_alt(struct usb_function * f,unsigned interface,unsigned alt)292 uvc_function_set_alt(struct usb_function *f, unsigned interface, unsigned alt)
293 {
294 struct uvc_device *uvc = to_uvc(f);
295 struct usb_composite_dev *cdev = f->config->cdev;
296 struct v4l2_event v4l2_event;
297 struct uvc_event *uvc_event = (void *)&v4l2_event.u.data;
298 int ret;
299
300 uvcg_info(f, "%s(%u, %u)\n", __func__, interface, alt);
301
302 if (interface == uvc->control_intf) {
303 if (alt)
304 return -EINVAL;
305
306 if (uvc->enable_interrupt_ep) {
307 uvcg_info(f, "reset UVC interrupt endpoint\n");
308 usb_ep_disable(uvc->interrupt_ep);
309
310 if (!uvc->interrupt_ep->desc)
311 if (config_ep_by_speed(cdev->gadget, f,
312 uvc->interrupt_ep))
313 return -EINVAL;
314
315 usb_ep_enable(uvc->interrupt_ep);
316 }
317
318 if (uvc->state == UVC_STATE_DISCONNECTED) {
319 memset(&v4l2_event, 0, sizeof(v4l2_event));
320 v4l2_event.type = UVC_EVENT_CONNECT;
321 uvc_event->speed = cdev->gadget->speed;
322 v4l2_event_queue(&uvc->vdev, &v4l2_event);
323
324 uvc->state = UVC_STATE_CONNECTED;
325 }
326
327 return 0;
328 }
329
330 if (interface != uvc->streaming_intf)
331 return -EINVAL;
332
333 /* TODO
334 if (usb_endpoint_xfer_bulk(&uvc->desc.vs_ep))
335 return alt ? -EINVAL : 0;
336 */
337
338 switch (alt) {
339 case 0:
340 if (uvc->state != UVC_STATE_STREAMING)
341 return 0;
342
343 memset(&v4l2_event, 0, sizeof(v4l2_event));
344 v4l2_event.type = UVC_EVENT_STREAMOFF;
345 v4l2_event_queue(&uvc->vdev, &v4l2_event);
346
347 return USB_GADGET_DELAYED_STATUS;
348
349 case 1:
350 if (uvc->state != UVC_STATE_CONNECTED)
351 return 0;
352
353 if (!uvc->video.ep)
354 return -EINVAL;
355
356 uvcg_info(f, "reset UVC\n");
357 usb_ep_disable(uvc->video.ep);
358
359 ret = config_ep_by_speed(f->config->cdev->gadget,
360 &(uvc->func), uvc->video.ep);
361 if (ret)
362 return ret;
363 usb_ep_enable(uvc->video.ep);
364
365 uvc->video.max_req_size = uvc->video.ep->maxpacket
366 * max_t(unsigned int, uvc->video.ep->maxburst, 1)
367 * (uvc->video.ep->mult);
368
369 memset(&v4l2_event, 0, sizeof(v4l2_event));
370 v4l2_event.type = UVC_EVENT_STREAMON;
371 v4l2_event_queue(&uvc->vdev, &v4l2_event);
372 return USB_GADGET_DELAYED_STATUS;
373
374 default:
375 return -EINVAL;
376 }
377 }
378
379 static void
uvc_function_disable(struct usb_function * f)380 uvc_function_disable(struct usb_function *f)
381 {
382 struct uvc_device *uvc = to_uvc(f);
383 struct v4l2_event v4l2_event;
384
385 uvcg_info(f, "%s()\n", __func__);
386
387 memset(&v4l2_event, 0, sizeof(v4l2_event));
388 v4l2_event.type = UVC_EVENT_DISCONNECT;
389 v4l2_event_queue(&uvc->vdev, &v4l2_event);
390
391 uvc->state = UVC_STATE_DISCONNECTED;
392
393 usb_ep_disable(uvc->video.ep);
394 if (uvc->enable_interrupt_ep)
395 usb_ep_disable(uvc->interrupt_ep);
396 }
397
398 /* --------------------------------------------------------------------------
399 * Connection / disconnection
400 */
401
402 void
uvc_function_connect(struct uvc_device * uvc)403 uvc_function_connect(struct uvc_device *uvc)
404 {
405 int ret;
406
407 if ((ret = usb_function_activate(&uvc->func)) < 0)
408 uvcg_info(&uvc->func, "UVC connect failed with %d\n", ret);
409 }
410
411 void
uvc_function_disconnect(struct uvc_device * uvc)412 uvc_function_disconnect(struct uvc_device *uvc)
413 {
414 int ret;
415
416 guard(mutex)(&uvc->lock);
417 if (uvc->func_unbound) {
418 dev_dbg(&uvc->vdev.dev, "skipping function deactivate (unbound)\n");
419 return;
420 }
421
422 if ((ret = usb_function_deactivate(&uvc->func)) < 0)
423 uvcg_info(&uvc->func, "UVC disconnect failed with %d\n", ret);
424 }
425
426 /* --------------------------------------------------------------------------
427 * USB probe and disconnect
428 */
429
function_name_show(struct device * dev,struct device_attribute * attr,char * buf)430 static ssize_t function_name_show(struct device *dev,
431 struct device_attribute *attr, char *buf)
432 {
433 struct uvc_device *uvc = dev_get_drvdata(dev);
434
435 return sprintf(buf, "%s\n", uvc->func.fi->group.cg_item.ci_name);
436 }
437
438 static DEVICE_ATTR_RO(function_name);
439
uvc_vdev_release(struct video_device * vdev)440 static void uvc_vdev_release(struct video_device *vdev)
441 {
442 struct uvc_device *uvc = video_get_drvdata(vdev);
443
444 /* Signal uvc_function_unbind() that the video device has been released */
445 if (uvc->vdev_release_done)
446 complete(uvc->vdev_release_done);
447 }
448
449 static int
uvc_register_video(struct uvc_device * uvc)450 uvc_register_video(struct uvc_device *uvc)
451 {
452 struct usb_composite_dev *cdev = uvc->func.config->cdev;
453 int ret;
454
455 /* TODO reference counting. */
456 memset(&uvc->vdev, 0, sizeof(uvc->vdev));
457 uvc->vdev.v4l2_dev = &uvc->v4l2_dev;
458 uvc->vdev.v4l2_dev->dev = &cdev->gadget->dev;
459 uvc->vdev.fops = &uvc_v4l2_fops;
460 uvc->vdev.ioctl_ops = &uvc_v4l2_ioctl_ops;
461 uvc->vdev.release = uvc_vdev_release;
462 uvc->vdev.vfl_dir = VFL_DIR_TX;
463 uvc->vdev.lock = &uvc->video.mutex;
464 uvc->vdev.device_caps = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
465 strscpy(uvc->vdev.name, cdev->gadget->name, sizeof(uvc->vdev.name));
466
467 video_set_drvdata(&uvc->vdev, uvc);
468
469 ret = video_register_device(&uvc->vdev, VFL_TYPE_VIDEO, -1);
470 if (ret < 0)
471 return ret;
472
473 ret = device_create_file(&uvc->vdev.dev, &dev_attr_function_name);
474 if (ret < 0) {
475 video_unregister_device(&uvc->vdev);
476 return ret;
477 }
478
479 return 0;
480 }
481
482 #define UVC_COPY_DESCRIPTOR(mem, dst, desc) \
483 do { \
484 memcpy(mem, desc, (desc)->bLength); \
485 *(dst)++ = mem; \
486 mem += (desc)->bLength; \
487 } while (0)
488
489 #define UVC_COPY_DESCRIPTORS(mem, dst, src) \
490 do { \
491 const struct usb_descriptor_header * const *__src; \
492 for (__src = src; *__src; ++__src) { \
493 memcpy(mem, *__src, (*__src)->bLength); \
494 *dst++ = mem; \
495 mem += (*__src)->bLength; \
496 } \
497 } while (0)
498
499 #define UVC_COPY_XU_DESCRIPTOR(mem, dst, desc) \
500 do { \
501 *(dst)++ = mem; \
502 memcpy(mem, desc, 22); /* bLength to bNrInPins */ \
503 mem += 22; \
504 \
505 memcpy(mem, (desc)->baSourceID, (desc)->bNrInPins); \
506 mem += (desc)->bNrInPins; \
507 \
508 memcpy(mem, &(desc)->bControlSize, 1); \
509 mem++; \
510 \
511 memcpy(mem, (desc)->bmControls, (desc)->bControlSize); \
512 mem += (desc)->bControlSize; \
513 \
514 memcpy(mem, &(desc)->iExtension, 1); \
515 mem++; \
516 } while (0)
517
518 static struct usb_descriptor_header **
uvc_copy_descriptors(struct uvc_device * uvc,enum usb_device_speed speed)519 uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
520 {
521 struct uvc_input_header_descriptor *uvc_streaming_header;
522 struct uvc_header_descriptor *uvc_control_header;
523 const struct uvc_descriptor_header * const *uvc_control_desc;
524 const struct uvc_descriptor_header * const *uvc_streaming_cls;
525 const struct usb_descriptor_header * const *uvc_streaming_std;
526 const struct usb_descriptor_header * const *src;
527 struct usb_descriptor_header **dst;
528 struct usb_descriptor_header **hdr;
529 struct uvcg_extension *xu;
530 unsigned int control_size;
531 unsigned int streaming_size;
532 unsigned int n_desc;
533 unsigned int bytes;
534 void *mem;
535
536 switch (speed) {
537 case USB_SPEED_SUPER_PLUS:
538 case USB_SPEED_SUPER:
539 uvc_control_desc = uvc->desc.ss_control;
540 uvc_streaming_cls = uvc->desc.ss_streaming;
541 uvc_streaming_std = uvc_ss_streaming;
542 break;
543
544 case USB_SPEED_HIGH:
545 uvc_control_desc = uvc->desc.fs_control;
546 uvc_streaming_cls = uvc->desc.hs_streaming;
547 uvc_streaming_std = uvc_hs_streaming;
548 break;
549
550 case USB_SPEED_FULL:
551 default:
552 uvc_control_desc = uvc->desc.fs_control;
553 uvc_streaming_cls = uvc->desc.fs_streaming;
554 uvc_streaming_std = uvc_fs_streaming;
555 break;
556 }
557
558 if (!uvc_control_desc || !uvc_streaming_cls)
559 return ERR_PTR(-ENODEV);
560
561 /*
562 * Descriptors layout
563 *
564 * uvc_iad
565 * uvc_control_intf
566 * Class-specific UVC control descriptors
567 * uvc_interrupt_ep
568 * uvc_interrupt_cs_ep
569 * uvc_ss_interrupt_comp (for SS only)
570 * uvc_streaming_intf_alt0
571 * Class-specific UVC streaming descriptors
572 * uvc_{fs|hs}_streaming
573 */
574
575 /* Count descriptors and compute their size. */
576 control_size = 0;
577 streaming_size = 0;
578 bytes = uvc_iad.bLength + uvc_control_intf.bLength
579 + uvc_streaming_intf_alt0.bLength;
580
581 n_desc = 3;
582 if (uvc->enable_interrupt_ep) {
583 bytes += uvc_interrupt_ep.bLength + uvc_interrupt_cs_ep.bLength;
584 n_desc += 2;
585
586 if (speed == USB_SPEED_SUPER ||
587 speed == USB_SPEED_SUPER_PLUS) {
588 bytes += uvc_ss_interrupt_comp.bLength;
589 n_desc += 1;
590 }
591 }
592
593 for (src = (const struct usb_descriptor_header **)uvc_control_desc;
594 *src; ++src) {
595 control_size += (*src)->bLength;
596 bytes += (*src)->bLength;
597 n_desc++;
598 }
599
600 list_for_each_entry(xu, uvc->desc.extension_units, list) {
601 control_size += xu->desc.bLength;
602 bytes += xu->desc.bLength;
603 n_desc++;
604 }
605
606 for (src = (const struct usb_descriptor_header **)uvc_streaming_cls;
607 *src; ++src) {
608 streaming_size += (*src)->bLength;
609 bytes += (*src)->bLength;
610 n_desc++;
611 }
612 for (src = uvc_streaming_std; *src; ++src) {
613 bytes += (*src)->bLength;
614 n_desc++;
615 }
616
617 mem = kmalloc((n_desc + 1) * sizeof(*src) + bytes, GFP_KERNEL);
618 if (mem == NULL)
619 return NULL;
620
621 hdr = mem;
622 dst = mem;
623 mem += (n_desc + 1) * sizeof(*src);
624
625 /* Copy the descriptors. */
626 UVC_COPY_DESCRIPTOR(mem, dst, &uvc_iad);
627 UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_intf);
628
629 uvc_control_header = mem;
630 UVC_COPY_DESCRIPTORS(mem, dst,
631 (const struct usb_descriptor_header **)uvc_control_desc);
632
633 list_for_each_entry(xu, uvc->desc.extension_units, list)
634 UVC_COPY_XU_DESCRIPTOR(mem, dst, &xu->desc);
635
636 uvc_control_header->wTotalLength = cpu_to_le16(control_size);
637 uvc_control_header->bInCollection = 1;
638 uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
639
640 if (uvc->enable_interrupt_ep) {
641 UVC_COPY_DESCRIPTOR(mem, dst, &uvc_interrupt_ep);
642 if (speed == USB_SPEED_SUPER ||
643 speed == USB_SPEED_SUPER_PLUS)
644 UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_interrupt_comp);
645
646 UVC_COPY_DESCRIPTOR(mem, dst, &uvc_interrupt_cs_ep);
647 }
648
649 UVC_COPY_DESCRIPTOR(mem, dst, &uvc_streaming_intf_alt0);
650
651 uvc_streaming_header = mem;
652 UVC_COPY_DESCRIPTORS(mem, dst,
653 (const struct usb_descriptor_header**)uvc_streaming_cls);
654 uvc_streaming_header->wTotalLength = cpu_to_le16(streaming_size);
655 uvc_streaming_header->bEndpointAddress = uvc->video.ep->address;
656
657 UVC_COPY_DESCRIPTORS(mem, dst, uvc_streaming_std);
658
659 *dst = NULL;
660 return hdr;
661 }
662
663 static int
uvc_function_bind(struct usb_configuration * c,struct usb_function * f)664 uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
665 {
666 struct usb_composite_dev *cdev = c->cdev;
667 struct uvc_device *uvc = to_uvc(f);
668 struct uvcg_extension *xu;
669 struct usb_string *us;
670 unsigned int max_packet_mult;
671 unsigned int max_packet_size;
672 struct usb_ep *ep;
673 struct f_uvc_opts *opts;
674 int ret = -EINVAL;
675
676 uvcg_info(f, "%s()\n", __func__);
677 scoped_guard(mutex, &uvc->lock)
678 uvc->func_unbound = false;
679
680 opts = fi_to_f_uvc_opts(f->fi);
681 /* Sanity check the streaming endpoint module parameters. */
682 opts->streaming_interval = clamp(opts->streaming_interval, 1U, 16U);
683 opts->streaming_maxpacket = clamp(opts->streaming_maxpacket, 1U, 3072U);
684 opts->streaming_maxburst = min(opts->streaming_maxburst, 15U);
685
686 /* For SS, wMaxPacketSize has to be 1024 if bMaxBurst is not 0 */
687 if (opts->streaming_maxburst &&
688 (opts->streaming_maxpacket % 1024) != 0) {
689 opts->streaming_maxpacket = roundup(opts->streaming_maxpacket, 1024);
690 uvcg_info(f, "overriding streaming_maxpacket to %d\n",
691 opts->streaming_maxpacket);
692 }
693
694 /*
695 * Fill in the FS/HS/SS Video Streaming specific descriptors from the
696 * module parameters.
697 *
698 * NOTE: We assume that the user knows what they are doing and won't
699 * give parameters that their UDC doesn't support.
700 */
701 if (opts->streaming_maxpacket <= 1024) {
702 max_packet_mult = 1;
703 max_packet_size = opts->streaming_maxpacket;
704 } else if (opts->streaming_maxpacket <= 2048) {
705 max_packet_mult = 2;
706 max_packet_size = opts->streaming_maxpacket / 2;
707 } else {
708 max_packet_mult = 3;
709 max_packet_size = opts->streaming_maxpacket / 3;
710 }
711
712 uvc_fs_streaming_ep.wMaxPacketSize =
713 cpu_to_le16(min(opts->streaming_maxpacket, 1023U));
714 uvc_fs_streaming_ep.bInterval = opts->streaming_interval;
715
716 uvc_hs_streaming_ep.wMaxPacketSize =
717 cpu_to_le16(max_packet_size | ((max_packet_mult - 1) << 11));
718
719 /* A high-bandwidth endpoint must specify a bInterval value of 1 */
720 if (max_packet_mult > 1)
721 uvc_hs_streaming_ep.bInterval = 1;
722 else
723 uvc_hs_streaming_ep.bInterval = opts->streaming_interval;
724
725 uvc_ss_streaming_ep.wMaxPacketSize = cpu_to_le16(max_packet_size);
726 uvc_ss_streaming_ep.bInterval = opts->streaming_interval;
727 uvc_ss_streaming_comp.bmAttributes = max_packet_mult - 1;
728 uvc_ss_streaming_comp.bMaxBurst = opts->streaming_maxburst;
729 uvc_ss_streaming_comp.wBytesPerInterval =
730 cpu_to_le16(max_packet_size * max_packet_mult *
731 (opts->streaming_maxburst + 1));
732
733 /* Allocate endpoints. */
734 if (opts->enable_interrupt_ep) {
735 ep = usb_ep_autoconfig(cdev->gadget, &uvc_interrupt_ep);
736 if (!ep) {
737 uvcg_info(f, "Unable to allocate interrupt EP\n");
738 goto error;
739 }
740 uvc->interrupt_ep = ep;
741 uvc_control_intf.bNumEndpoints = 1;
742 }
743 uvc->enable_interrupt_ep = opts->enable_interrupt_ep;
744
745 /*
746 * gadget_is_{super|dual}speed() API check UDC controller capitblity. It should pass down
747 * highest speed endpoint descriptor to UDC controller. So UDC controller driver can reserve
748 * enough resource at check_config(), especially mult and maxburst. So UDC driver (such as
749 * cdns3) can know need at least (mult + 1) * (maxburst + 1) * wMaxPacketSize internal
750 * memory for this uvc functions. This is the only straightforward method to resolve the UDC
751 * resource allocation issue in the current gadget framework.
752 */
753 if (gadget_is_superspeed(c->cdev->gadget))
754 ep = usb_ep_autoconfig_ss(cdev->gadget, &uvc_ss_streaming_ep,
755 &uvc_ss_streaming_comp);
756 else if (gadget_is_dualspeed(cdev->gadget))
757 ep = usb_ep_autoconfig(cdev->gadget, &uvc_hs_streaming_ep);
758 else
759 ep = usb_ep_autoconfig(cdev->gadget, &uvc_fs_streaming_ep);
760
761 if (!ep) {
762 uvcg_info(f, "Unable to allocate streaming EP\n");
763 goto error;
764 }
765 uvc->video.ep = ep;
766
767 uvc_fs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
768 uvc_hs_streaming_ep.bEndpointAddress = uvc->video.ep->address;
769 uvc_ss_streaming_ep.bEndpointAddress = uvc->video.ep->address;
770
771 /*
772 * XUs can have an arbitrary string descriptor describing them. If they
773 * have one pick up the ID.
774 */
775 list_for_each_entry(xu, &opts->extension_units, list)
776 if (xu->string_descriptor_index)
777 xu->desc.iExtension = cdev->usb_strings[xu->string_descriptor_index].id;
778
779 /*
780 * We attach the hard-coded defaults incase the user does not provide
781 * any more appropriate strings through configfs.
782 */
783 uvc_en_us_strings[UVC_STRING_CONTROL_IDX].s = opts->function_name;
784 us = usb_gstrings_attach(cdev, uvc_function_strings,
785 ARRAY_SIZE(uvc_en_us_strings));
786 if (IS_ERR(us)) {
787 ret = PTR_ERR(us);
788 goto error;
789 }
790
791 uvc_iad.iFunction = opts->iad_index ? cdev->usb_strings[opts->iad_index].id :
792 us[UVC_STRING_CONTROL_IDX].id;
793 uvc_streaming_intf_alt0.iInterface = opts->vs0_index ?
794 cdev->usb_strings[opts->vs0_index].id :
795 us[UVC_STRING_STREAMING_IDX].id;
796 uvc_streaming_intf_alt1.iInterface = opts->vs1_index ?
797 cdev->usb_strings[opts->vs1_index].id :
798 us[UVC_STRING_STREAMING_IDX].id;
799
800 /* Allocate interface IDs. */
801 if ((ret = usb_interface_id(c, f)) < 0)
802 goto error;
803 uvc_iad.bFirstInterface = ret;
804 uvc_control_intf.bInterfaceNumber = ret;
805 uvc->control_intf = ret;
806 opts->control_interface = ret;
807
808 if ((ret = usb_interface_id(c, f)) < 0)
809 goto error;
810 uvc_streaming_intf_alt0.bInterfaceNumber = ret;
811 uvc_streaming_intf_alt1.bInterfaceNumber = ret;
812 uvc->streaming_intf = ret;
813 opts->streaming_interface = ret;
814
815 /* Copy descriptors */
816 f->fs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_FULL);
817 if (IS_ERR(f->fs_descriptors)) {
818 ret = PTR_ERR(f->fs_descriptors);
819 f->fs_descriptors = NULL;
820 goto error;
821 }
822
823 f->hs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_HIGH);
824 if (IS_ERR(f->hs_descriptors)) {
825 ret = PTR_ERR(f->hs_descriptors);
826 f->hs_descriptors = NULL;
827 goto error;
828 }
829
830 f->ss_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER);
831 if (IS_ERR(f->ss_descriptors)) {
832 ret = PTR_ERR(f->ss_descriptors);
833 f->ss_descriptors = NULL;
834 goto error;
835 }
836
837 f->ssp_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER_PLUS);
838 if (IS_ERR(f->ssp_descriptors)) {
839 ret = PTR_ERR(f->ssp_descriptors);
840 f->ssp_descriptors = NULL;
841 goto error;
842 }
843
844 /* Preallocate control endpoint request. */
845 uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
846 uvc->control_buf = kmalloc(UVC_MAX_REQUEST_SIZE, GFP_KERNEL);
847 if (uvc->control_req == NULL || uvc->control_buf == NULL) {
848 ret = -ENOMEM;
849 goto error;
850 }
851
852 uvc->control_req->buf = uvc->control_buf;
853 uvc->control_req->complete = uvc_function_ep0_complete;
854 uvc->control_req->context = uvc;
855
856 if (v4l2_device_register(&cdev->gadget->dev, &uvc->v4l2_dev)) {
857 uvcg_err(f, "failed to register V4L2 device\n");
858 goto error;
859 }
860
861 /* Initialise video. */
862 ret = uvcg_video_init(&uvc->video, uvc);
863 if (ret < 0)
864 goto v4l2_error;
865
866 /* Register a V4L2 device. */
867 ret = uvc_register_video(uvc);
868 if (ret < 0) {
869 uvcg_err(f, "failed to register video device\n");
870 goto v4l2_error;
871 }
872
873 return 0;
874
875 v4l2_error:
876 v4l2_device_unregister(&uvc->v4l2_dev);
877 error:
878 if (uvc->control_req)
879 usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
880 kfree(uvc->control_buf);
881
882 usb_free_all_descriptors(f);
883 return ret;
884 }
885
886 /* --------------------------------------------------------------------------
887 * USB gadget function
888 */
889
uvc_free_inst(struct usb_function_instance * f)890 static void uvc_free_inst(struct usb_function_instance *f)
891 {
892 struct f_uvc_opts *opts = fi_to_f_uvc_opts(f);
893
894 mutex_destroy(&opts->lock);
895 kfree(opts);
896 }
897
uvc_alloc_inst(void)898 static struct usb_function_instance *uvc_alloc_inst(void)
899 {
900 struct f_uvc_opts *opts;
901 struct uvc_camera_terminal_descriptor *cd;
902 struct uvc_processing_unit_descriptor *pd;
903 struct uvc_output_terminal_descriptor *od;
904 struct uvc_descriptor_header **ctl_cls;
905 int ret;
906
907 opts = kzalloc_obj(*opts);
908 if (!opts)
909 return ERR_PTR(-ENOMEM);
910 opts->func_inst.free_func_inst = uvc_free_inst;
911 mutex_init(&opts->lock);
912
913 cd = &opts->uvc_camera_terminal;
914 cd->bLength = UVC_DT_CAMERA_TERMINAL_SIZE(3);
915 cd->bDescriptorType = USB_DT_CS_INTERFACE;
916 cd->bDescriptorSubType = UVC_VC_INPUT_TERMINAL;
917 cd->bTerminalID = 1;
918 cd->wTerminalType = cpu_to_le16(0x0201);
919 cd->bAssocTerminal = 0;
920 cd->iTerminal = 0;
921 cd->wObjectiveFocalLengthMin = cpu_to_le16(0);
922 cd->wObjectiveFocalLengthMax = cpu_to_le16(0);
923 cd->wOcularFocalLength = cpu_to_le16(0);
924 cd->bControlSize = 3;
925 cd->bmControls[0] = 2;
926 cd->bmControls[1] = 0;
927 cd->bmControls[2] = 0;
928
929 pd = &opts->uvc_processing;
930 pd->bLength = UVC_DT_PROCESSING_UNIT_SIZE(2);
931 pd->bDescriptorType = USB_DT_CS_INTERFACE;
932 pd->bDescriptorSubType = UVC_VC_PROCESSING_UNIT;
933 pd->bUnitID = 2;
934 pd->bSourceID = 1;
935 pd->wMaxMultiplier = cpu_to_le16(16*1024);
936 pd->bControlSize = 2;
937 pd->bmControls[0] = 1;
938 pd->bmControls[1] = 0;
939 pd->iProcessing = 0;
940 pd->bmVideoStandards = 0;
941
942 od = &opts->uvc_output_terminal;
943 od->bLength = UVC_DT_OUTPUT_TERMINAL_SIZE;
944 od->bDescriptorType = USB_DT_CS_INTERFACE;
945 od->bDescriptorSubType = UVC_VC_OUTPUT_TERMINAL;
946 od->bTerminalID = 3;
947 od->wTerminalType = cpu_to_le16(0x0101);
948 od->bAssocTerminal = 0;
949 od->bSourceID = 2;
950 od->iTerminal = 0;
951
952 /*
953 * With the ability to add XUs to the UVC function graph, we need to be
954 * able to allocate unique unit IDs to them. The IDs are 1-based, with
955 * the CT, PU and OT above consuming the first 3.
956 */
957 opts->last_unit_id = 3;
958
959 /* Prepare fs control class descriptors for configfs-based gadgets */
960 ctl_cls = opts->uvc_fs_control_cls;
961 ctl_cls[0] = NULL; /* assigned elsewhere by configfs */
962 ctl_cls[1] = (struct uvc_descriptor_header *)cd;
963 ctl_cls[2] = (struct uvc_descriptor_header *)pd;
964 ctl_cls[3] = (struct uvc_descriptor_header *)od;
965 ctl_cls[4] = NULL; /* NULL-terminate */
966 opts->fs_control =
967 (const struct uvc_descriptor_header * const *)ctl_cls;
968
969 /* Prepare hs control class descriptors for configfs-based gadgets */
970 ctl_cls = opts->uvc_ss_control_cls;
971 ctl_cls[0] = NULL; /* assigned elsewhere by configfs */
972 ctl_cls[1] = (struct uvc_descriptor_header *)cd;
973 ctl_cls[2] = (struct uvc_descriptor_header *)pd;
974 ctl_cls[3] = (struct uvc_descriptor_header *)od;
975 ctl_cls[4] = NULL; /* NULL-terminate */
976 opts->ss_control =
977 (const struct uvc_descriptor_header * const *)ctl_cls;
978
979 INIT_LIST_HEAD(&opts->extension_units);
980
981 opts->streaming_interval = 1;
982 opts->streaming_maxpacket = 1024;
983 snprintf(opts->function_name, sizeof(opts->function_name), "UVC Camera");
984
985 ret = uvcg_attach_configfs(opts);
986 if (ret < 0) {
987 kfree(opts);
988 return ERR_PTR(ret);
989 }
990
991 return &opts->func_inst;
992 }
993
uvc_free(struct usb_function * f)994 static void uvc_free(struct usb_function *f)
995 {
996 struct uvc_device *uvc = to_uvc(f);
997 struct f_uvc_opts *opts = container_of(f->fi, struct f_uvc_opts,
998 func_inst);
999 if (!opts->header)
1000 config_item_put(&uvc->header->item);
1001 --opts->refcnt;
1002 kfree(uvc);
1003 }
1004
uvc_function_unbind(struct usb_configuration * c,struct usb_function * f)1005 static void uvc_function_unbind(struct usb_configuration *c,
1006 struct usb_function *f)
1007 {
1008 DECLARE_COMPLETION_ONSTACK(vdev_release_done);
1009 struct usb_composite_dev *cdev = c->cdev;
1010 struct uvc_device *uvc = to_uvc(f);
1011 struct uvc_video *video = &uvc->video;
1012 long wait_ret = 1;
1013 bool connected;
1014
1015 uvcg_info(f, "%s()\n", __func__);
1016 scoped_guard(mutex, &uvc->lock) {
1017 uvc->func_unbound = true;
1018 uvc->vdev_release_done = &vdev_release_done;
1019 connected = uvc->func_connected;
1020 }
1021
1022 kthread_cancel_work_sync(&video->hw_submit);
1023
1024 if (video->async_wq)
1025 destroy_workqueue(video->async_wq);
1026
1027 /*
1028 * If we know we're connected via v4l2, then there should be a cleanup
1029 * of the device from userspace either via UVC_EVENT_DISCONNECT or
1030 * though the video device removal uevent. Allow some time for the
1031 * application to close out before things get deleted.
1032 */
1033 if (connected) {
1034 uvcg_dbg(f, "waiting for clean disconnect\n");
1035 wait_ret = wait_event_interruptible_timeout(uvc->func_connected_queue,
1036 uvc->func_connected == false, msecs_to_jiffies(500));
1037 uvcg_dbg(f, "done waiting with ret: %ld\n", wait_ret);
1038 }
1039
1040 device_remove_file(&uvc->vdev.dev, &dev_attr_function_name);
1041 video_unregister_device(&uvc->vdev);
1042 v4l2_device_unregister(&uvc->v4l2_dev);
1043
1044 scoped_guard(mutex, &uvc->lock)
1045 connected = uvc->func_connected;
1046
1047 if (connected) {
1048 /*
1049 * Wait for the release to occur to ensure there are no longer any
1050 * pending operations that may cause panics when resources are cleaned
1051 * up.
1052 */
1053 uvcg_warn(f, "%s no clean disconnect, wait for release\n", __func__);
1054 wait_ret = wait_event_interruptible_timeout(uvc->func_connected_queue,
1055 uvc->func_connected == false, msecs_to_jiffies(1000));
1056 uvcg_dbg(f, "done waiting for release with ret: %ld\n", wait_ret);
1057 }
1058
1059 /* Wait for the video device to be released */
1060 wait_for_completion(&vdev_release_done);
1061 uvc->vdev_release_done = NULL;
1062
1063 usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
1064 kfree(uvc->control_buf);
1065
1066 usb_free_all_descriptors(f);
1067 }
1068
uvc_alloc(struct usb_function_instance * fi)1069 static struct usb_function *uvc_alloc(struct usb_function_instance *fi)
1070 {
1071 struct uvc_device *uvc;
1072 struct f_uvc_opts *opts;
1073 struct uvc_descriptor_header **strm_cls;
1074 struct config_item *streaming, *header, *h;
1075
1076 uvc = kzalloc_obj(*uvc);
1077 if (uvc == NULL)
1078 return ERR_PTR(-ENOMEM);
1079
1080 mutex_init(&uvc->video.mutex);
1081 mutex_init(&uvc->lock);
1082 uvc->func_unbound = true;
1083 uvc->state = UVC_STATE_DISCONNECTED;
1084 init_waitqueue_head(&uvc->func_connected_queue);
1085 opts = fi_to_f_uvc_opts(fi);
1086
1087 mutex_lock(&opts->lock);
1088 if (opts->uvc_fs_streaming_cls) {
1089 strm_cls = opts->uvc_fs_streaming_cls;
1090 opts->fs_streaming =
1091 (const struct uvc_descriptor_header * const *)strm_cls;
1092 }
1093 if (opts->uvc_hs_streaming_cls) {
1094 strm_cls = opts->uvc_hs_streaming_cls;
1095 opts->hs_streaming =
1096 (const struct uvc_descriptor_header * const *)strm_cls;
1097 }
1098 if (opts->uvc_ss_streaming_cls) {
1099 strm_cls = opts->uvc_ss_streaming_cls;
1100 opts->ss_streaming =
1101 (const struct uvc_descriptor_header * const *)strm_cls;
1102 }
1103
1104 uvc->desc.fs_control = opts->fs_control;
1105 uvc->desc.ss_control = opts->ss_control;
1106 uvc->desc.fs_streaming = opts->fs_streaming;
1107 uvc->desc.hs_streaming = opts->hs_streaming;
1108 uvc->desc.ss_streaming = opts->ss_streaming;
1109
1110 if (opts->header) {
1111 uvc->header = opts->header;
1112 } else {
1113 streaming = config_group_find_item(&opts->func_inst.group, "streaming");
1114 if (!streaming)
1115 goto err_config;
1116
1117 header = config_group_find_item(to_config_group(streaming), "header");
1118 config_item_put(streaming);
1119 if (!header)
1120 goto err_config;
1121
1122 h = config_group_find_item(to_config_group(header), "h");
1123 config_item_put(header);
1124 if (!h)
1125 goto err_config;
1126
1127 uvc->header = to_uvcg_streaming_header(h);
1128 if (!uvc->header->linked) {
1129 mutex_unlock(&opts->lock);
1130 kfree(uvc);
1131 return ERR_PTR(-EBUSY);
1132 }
1133 }
1134
1135 uvc->desc.extension_units = &opts->extension_units;
1136
1137 ++opts->refcnt;
1138 mutex_unlock(&opts->lock);
1139
1140 /* Register the function. */
1141 uvc->func.name = "uvc";
1142 uvc->func.bind = uvc_function_bind;
1143 uvc->func.unbind = uvc_function_unbind;
1144 uvc->func.get_alt = uvc_function_get_alt;
1145 uvc->func.set_alt = uvc_function_set_alt;
1146 uvc->func.disable = uvc_function_disable;
1147 uvc->func.setup = uvc_function_setup;
1148 uvc->func.free_func = uvc_free;
1149 uvc->func.bind_deactivated = true;
1150
1151 return &uvc->func;
1152
1153 err_config:
1154 mutex_unlock(&opts->lock);
1155 kfree(uvc);
1156 return ERR_PTR(-ENOENT);
1157 }
1158
1159 DECLARE_USB_FUNCTION_INIT(uvc, uvc_alloc_inst, uvc_alloc);
1160 MODULE_DESCRIPTION("USB Video Class Gadget driver");
1161 MODULE_LICENSE("GPL");
1162 MODULE_AUTHOR("Laurent Pinchart");
1163