1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Main USB camera driver
4  *
5  * Copyright (C) 2008-2011 Jean-François Moine <http://moinejf.free.fr>
6  *
7  * Camera button input handling by Márton Németh
8  * Copyright (C) 2009-2010 Márton Németh <nm127@freemail.hu>
9  */
10 
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12 
13 #define GSPCA_VERSION	"2.14.0"
14 
15 #include <linux/init.h>
16 #include <linux/fs.h>
17 #include <linux/vmalloc.h>
18 #include <linux/sched.h>
19 #include <linux/slab.h>
20 #include <linux/mm.h>
21 #include <linux/string.h>
22 #include <linux/pagemap.h>
23 #include <linux/io.h>
24 #include <asm/page.h>
25 #include <linux/uaccess.h>
26 #include <linux/ktime.h>
27 #include <media/v4l2-ioctl.h>
28 #include <media/v4l2-ctrls.h>
29 #include <media/v4l2-fh.h>
30 #include <media/v4l2-event.h>
31 
32 #include "gspca.h"
33 
34 #if IS_ENABLED(CONFIG_INPUT)
35 #include <linux/input.h>
36 #include <linux/usb/input.h>
37 #endif
38 
39 /* global values */
40 #define DEF_NURBS 3		/* default number of URBs */
41 #if DEF_NURBS > MAX_NURBS
42 #error "DEF_NURBS too big"
43 #endif
44 
45 MODULE_AUTHOR("Jean-François Moine <http://moinejf.free.fr>");
46 MODULE_DESCRIPTION("GSPCA USB Camera Driver");
47 MODULE_LICENSE("GPL");
48 MODULE_VERSION(GSPCA_VERSION);
49 
50 int gspca_debug;
51 EXPORT_SYMBOL(gspca_debug);
52 
PDEBUG_MODE(struct gspca_dev * gspca_dev,int debug,char * txt,__u32 pixfmt,int w,int h)53 static void PDEBUG_MODE(struct gspca_dev *gspca_dev, int debug, char *txt,
54 			__u32 pixfmt, int w, int h)
55 {
56 	if ((pixfmt >> 24) >= '0' && (pixfmt >> 24) <= 'z') {
57 		gspca_dbg(gspca_dev, debug, "%s %c%c%c%c %dx%d\n",
58 			  txt,
59 			  pixfmt & 0xff,
60 			  (pixfmt >> 8) & 0xff,
61 			  (pixfmt >> 16) & 0xff,
62 			  pixfmt >> 24,
63 			  w, h);
64 	} else {
65 		gspca_dbg(gspca_dev, debug, "%s 0x%08x %dx%d\n",
66 			  txt,
67 			  pixfmt,
68 			  w, h);
69 	}
70 }
71 
72 /* specific memory types - !! should be different from V4L2_MEMORY_xxx */
73 #define GSPCA_MEMORY_NO 0	/* V4L2_MEMORY_xxx starts from 1 */
74 #define GSPCA_MEMORY_READ 7
75 
76 /*
77  * Input and interrupt endpoint handling functions
78  */
79 #if IS_ENABLED(CONFIG_INPUT)
int_irq(struct urb * urb)80 static void int_irq(struct urb *urb)
81 {
82 	struct gspca_dev *gspca_dev = (struct gspca_dev *) urb->context;
83 	int ret;
84 
85 	ret = urb->status;
86 	switch (ret) {
87 	case 0:
88 		if (gspca_dev->sd_desc->int_pkt_scan(gspca_dev,
89 		    urb->transfer_buffer, urb->actual_length) < 0) {
90 			gspca_err(gspca_dev, "Unknown packet received\n");
91 		}
92 		break;
93 
94 	case -ENOENT:
95 	case -ECONNRESET:
96 	case -ENODEV:
97 	case -ESHUTDOWN:
98 		/* Stop is requested either by software or hardware is gone,
99 		 * keep the ret value non-zero and don't resubmit later.
100 		 */
101 		break;
102 
103 	default:
104 		gspca_err(gspca_dev, "URB error %i, resubmitting\n",
105 			  urb->status);
106 		urb->status = 0;
107 		ret = 0;
108 	}
109 
110 	if (ret == 0) {
111 		ret = usb_submit_urb(urb, GFP_ATOMIC);
112 		if (ret < 0)
113 			pr_err("Resubmit URB failed with error %i\n", ret);
114 	}
115 }
116 
gspca_input_connect(struct gspca_dev * dev)117 static int gspca_input_connect(struct gspca_dev *dev)
118 {
119 	struct input_dev *input_dev;
120 	int err = 0;
121 
122 	dev->input_dev = NULL;
123 	if (dev->sd_desc->int_pkt_scan || dev->sd_desc->other_input)  {
124 		input_dev = input_allocate_device();
125 		if (!input_dev)
126 			return -ENOMEM;
127 
128 		usb_make_path(dev->dev, dev->phys, sizeof(dev->phys));
129 		strlcat(dev->phys, "/input0", sizeof(dev->phys));
130 
131 		input_dev->name = dev->sd_desc->name;
132 		input_dev->phys = dev->phys;
133 
134 		usb_to_input_id(dev->dev, &input_dev->id);
135 
136 		input_dev->evbit[0] = BIT_MASK(EV_KEY);
137 		input_dev->keybit[BIT_WORD(KEY_CAMERA)] = BIT_MASK(KEY_CAMERA);
138 		input_dev->dev.parent = &dev->dev->dev;
139 
140 		err = input_register_device(input_dev);
141 		if (err) {
142 			pr_err("Input device registration failed with error %i\n",
143 			       err);
144 			input_dev->dev.parent = NULL;
145 			input_free_device(input_dev);
146 		} else {
147 			dev->input_dev = input_dev;
148 		}
149 	}
150 
151 	return err;
152 }
153 
alloc_and_submit_int_urb(struct gspca_dev * gspca_dev,struct usb_endpoint_descriptor * ep)154 static int alloc_and_submit_int_urb(struct gspca_dev *gspca_dev,
155 			  struct usb_endpoint_descriptor *ep)
156 {
157 	unsigned int buffer_len;
158 	int interval;
159 	struct urb *urb;
160 	struct usb_device *dev;
161 	void *buffer = NULL;
162 	int ret = -EINVAL;
163 
164 	buffer_len = le16_to_cpu(ep->wMaxPacketSize);
165 	interval = ep->bInterval;
166 	gspca_dbg(gspca_dev, D_CONF, "found int in endpoint: 0x%x, buffer_len=%u, interval=%u\n",
167 		  ep->bEndpointAddress, buffer_len, interval);
168 
169 	dev = gspca_dev->dev;
170 
171 	urb = usb_alloc_urb(0, GFP_KERNEL);
172 	if (!urb) {
173 		ret = -ENOMEM;
174 		goto error;
175 	}
176 
177 	buffer = usb_alloc_coherent(dev, buffer_len,
178 				GFP_KERNEL, &urb->transfer_dma);
179 	if (!buffer) {
180 		ret = -ENOMEM;
181 		goto error_buffer;
182 	}
183 	usb_fill_int_urb(urb, dev,
184 		usb_rcvintpipe(dev, ep->bEndpointAddress),
185 		buffer, buffer_len,
186 		int_irq, (void *)gspca_dev, interval);
187 	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
188 	ret = usb_submit_urb(urb, GFP_KERNEL);
189 	if (ret < 0) {
190 		gspca_err(gspca_dev, "submit int URB failed with error %i\n",
191 			  ret);
192 		goto error_submit;
193 	}
194 	gspca_dev->int_urb = urb;
195 	return ret;
196 
197 error_submit:
198 	usb_free_coherent(dev,
199 			  urb->transfer_buffer_length,
200 			  urb->transfer_buffer,
201 			  urb->transfer_dma);
202 error_buffer:
203 	usb_free_urb(urb);
204 error:
205 	return ret;
206 }
207 
gspca_input_create_urb(struct gspca_dev * gspca_dev)208 static void gspca_input_create_urb(struct gspca_dev *gspca_dev)
209 {
210 	struct usb_interface *intf;
211 	struct usb_host_interface *intf_desc;
212 	struct usb_endpoint_descriptor *ep;
213 	int i;
214 
215 	if (gspca_dev->sd_desc->int_pkt_scan)  {
216 		intf = usb_ifnum_to_if(gspca_dev->dev, gspca_dev->iface);
217 		intf_desc = intf->cur_altsetting;
218 		for (i = 0; i < intf_desc->desc.bNumEndpoints; i++) {
219 			ep = &intf_desc->endpoint[i].desc;
220 			if (usb_endpoint_dir_in(ep) &&
221 			    usb_endpoint_xfer_int(ep)) {
222 
223 				alloc_and_submit_int_urb(gspca_dev, ep);
224 				break;
225 			}
226 		}
227 	}
228 }
229 
gspca_input_destroy_urb(struct gspca_dev * gspca_dev)230 static void gspca_input_destroy_urb(struct gspca_dev *gspca_dev)
231 {
232 	struct urb *urb;
233 
234 	urb = gspca_dev->int_urb;
235 	if (urb) {
236 		gspca_dev->int_urb = NULL;
237 		usb_kill_urb(urb);
238 		usb_free_coherent(gspca_dev->dev,
239 				  urb->transfer_buffer_length,
240 				  urb->transfer_buffer,
241 				  urb->transfer_dma);
242 		usb_free_urb(urb);
243 	}
244 }
245 #else
gspca_input_destroy_urb(struct gspca_dev * gspca_dev)246 static inline void gspca_input_destroy_urb(struct gspca_dev *gspca_dev)
247 {
248 }
249 
gspca_input_create_urb(struct gspca_dev * gspca_dev)250 static inline void gspca_input_create_urb(struct gspca_dev *gspca_dev)
251 {
252 }
253 
gspca_input_connect(struct gspca_dev * dev)254 static inline int gspca_input_connect(struct gspca_dev *dev)
255 {
256 	return 0;
257 }
258 #endif
259 
260 /*
261  * fill a video frame from an URB and resubmit
262  */
fill_frame(struct gspca_dev * gspca_dev,struct urb * urb)263 static void fill_frame(struct gspca_dev *gspca_dev,
264 			struct urb *urb)
265 {
266 	u8 *data;		/* address of data in the iso message */
267 	int i, len, st;
268 	cam_pkt_op pkt_scan;
269 
270 	if (urb->status != 0) {
271 		if (urb->status == -ESHUTDOWN)
272 			return;		/* disconnection */
273 #ifdef CONFIG_PM
274 		if (gspca_dev->frozen)
275 			return;
276 #endif
277 		gspca_err(gspca_dev, "urb status: %d\n", urb->status);
278 		urb->status = 0;
279 		goto resubmit;
280 	}
281 	pkt_scan = gspca_dev->sd_desc->pkt_scan;
282 	for (i = 0; i < urb->number_of_packets; i++) {
283 		len = urb->iso_frame_desc[i].actual_length;
284 
285 		/* check the packet status and length */
286 		st = urb->iso_frame_desc[i].status;
287 		if (st) {
288 			gspca_dbg(gspca_dev, D_PACK, "ISOC data error: [%d] len=%d, status=%d\n",
289 			       i, len, st);
290 			gspca_dev->last_packet_type = DISCARD_PACKET;
291 			continue;
292 		}
293 		if (len == 0) {
294 			if (gspca_dev->empty_packet == 0)
295 				gspca_dev->empty_packet = 1;
296 			continue;
297 		}
298 
299 		/* let the packet be analyzed by the subdriver */
300 		gspca_dbg(gspca_dev, D_PACK, "packet [%d] o:%d l:%d\n",
301 			  i, urb->iso_frame_desc[i].offset, len);
302 		data = (u8 *) urb->transfer_buffer
303 					+ urb->iso_frame_desc[i].offset;
304 		pkt_scan(gspca_dev, data, len);
305 	}
306 
307 resubmit:
308 	if (!gspca_dev->streaming)
309 		return;
310 	/* resubmit the URB */
311 	st = usb_submit_urb(urb, GFP_ATOMIC);
312 	if (st < 0)
313 		pr_err("usb_submit_urb() ret %d\n", st);
314 }
315 
316 /*
317  * ISOC message interrupt from the USB device
318  *
319  * Analyse each packet and call the subdriver for copy to the frame buffer.
320  */
isoc_irq(struct urb * urb)321 static void isoc_irq(struct urb *urb)
322 {
323 	struct gspca_dev *gspca_dev = (struct gspca_dev *) urb->context;
324 
325 	gspca_dbg(gspca_dev, D_PACK, "isoc irq\n");
326 	if (!gspca_dev->streaming)
327 		return;
328 	fill_frame(gspca_dev, urb);
329 }
330 
331 /*
332  * bulk message interrupt from the USB device
333  */
bulk_irq(struct urb * urb)334 static void bulk_irq(struct urb *urb)
335 {
336 	struct gspca_dev *gspca_dev = (struct gspca_dev *) urb->context;
337 	int st;
338 
339 	gspca_dbg(gspca_dev, D_PACK, "bulk irq\n");
340 	if (!gspca_dev->streaming)
341 		return;
342 	switch (urb->status) {
343 	case 0:
344 		break;
345 	case -ESHUTDOWN:
346 		return;		/* disconnection */
347 	default:
348 #ifdef CONFIG_PM
349 		if (gspca_dev->frozen)
350 			return;
351 #endif
352 		gspca_err(gspca_dev, "urb status: %d\n", urb->status);
353 		urb->status = 0;
354 		goto resubmit;
355 	}
356 
357 	gspca_dbg(gspca_dev, D_PACK, "packet l:%d\n", urb->actual_length);
358 	gspca_dev->sd_desc->pkt_scan(gspca_dev,
359 				urb->transfer_buffer,
360 				urb->actual_length);
361 
362 resubmit:
363 	if (!gspca_dev->streaming)
364 		return;
365 	/* resubmit the URB */
366 	if (gspca_dev->cam.bulk_nurbs != 0) {
367 		st = usb_submit_urb(urb, GFP_ATOMIC);
368 		if (st < 0)
369 			pr_err("usb_submit_urb() ret %d\n", st);
370 	}
371 }
372 
373 /*
374  * add data to the current frame
375  *
376  * This function is called by the subdrivers at interrupt level.
377  *
378  * To build a frame, these ones must add
379  *	- one FIRST_PACKET
380  *	- 0 or many INTER_PACKETs
381  *	- one LAST_PACKET
382  * DISCARD_PACKET invalidates the whole frame.
383  */
gspca_frame_add(struct gspca_dev * gspca_dev,enum gspca_packet_type packet_type,const u8 * data,int len)384 void gspca_frame_add(struct gspca_dev *gspca_dev,
385 			enum gspca_packet_type packet_type,
386 			const u8 *data,
387 			int len)
388 {
389 	struct gspca_buffer *buf;
390 	unsigned long flags;
391 
392 	gspca_dbg(gspca_dev, D_PACK, "add t:%d l:%d\n",	packet_type, len);
393 
394 	spin_lock_irqsave(&gspca_dev->qlock, flags);
395 	buf = list_first_entry_or_null(&gspca_dev->buf_list,
396 				       typeof(*buf), list);
397 	spin_unlock_irqrestore(&gspca_dev->qlock, flags);
398 
399 	if (packet_type == FIRST_PACKET) {
400 		/* if there is no queued buffer, discard the whole frame */
401 		if (!buf) {
402 			gspca_dev->last_packet_type = DISCARD_PACKET;
403 			gspca_dev->sequence++;
404 			return;
405 		}
406 		gspca_dev->image = vb2_plane_vaddr(&buf->vb.vb2_buf, 0);
407 		gspca_dev->image_len = 0;
408 	} else {
409 		switch (gspca_dev->last_packet_type) {
410 		case DISCARD_PACKET:
411 			if (packet_type == LAST_PACKET) {
412 				gspca_dev->last_packet_type = packet_type;
413 				gspca_dev->image = NULL;
414 				gspca_dev->image_len = 0;
415 			}
416 			return;
417 		case LAST_PACKET:
418 			return;
419 		}
420 	}
421 
422 	/* append the packet to the frame buffer */
423 	if (len > 0) {
424 		if (gspca_dev->image_len + len > PAGE_ALIGN(gspca_dev->pixfmt.sizeimage)) {
425 			gspca_err(gspca_dev, "frame overflow %d > %d\n",
426 				  gspca_dev->image_len + len,
427 				  PAGE_ALIGN(gspca_dev->pixfmt.sizeimage));
428 			packet_type = DISCARD_PACKET;
429 		} else {
430 /* !! image is NULL only when last pkt is LAST or DISCARD
431 			if (gspca_dev->image == NULL) {
432 				pr_err("gspca_frame_add() image == NULL\n");
433 				return;
434 			}
435  */
436 			memcpy(gspca_dev->image + gspca_dev->image_len,
437 				data, len);
438 			gspca_dev->image_len += len;
439 		}
440 	}
441 	gspca_dev->last_packet_type = packet_type;
442 
443 	/* if last packet, invalidate packet concatenation until
444 	 * next first packet, wake up the application and advance
445 	 * in the queue */
446 	if (packet_type == LAST_PACKET) {
447 		if (gspca_dev->image_len > gspca_dev->pixfmt.sizeimage)
448 			gspca_dev->image_len = gspca_dev->pixfmt.sizeimage;
449 		spin_lock_irqsave(&gspca_dev->qlock, flags);
450 		list_del(&buf->list);
451 		spin_unlock_irqrestore(&gspca_dev->qlock, flags);
452 		buf->vb.vb2_buf.timestamp = ktime_get_ns();
453 		vb2_set_plane_payload(&buf->vb.vb2_buf, 0,
454 				      gspca_dev->image_len);
455 		buf->vb.sequence = gspca_dev->sequence++;
456 		buf->vb.field = V4L2_FIELD_NONE;
457 		gspca_dbg(gspca_dev, D_FRAM, "frame complete len:%d\n",
458 			  gspca_dev->image_len);
459 		vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
460 		gspca_dev->image = NULL;
461 		gspca_dev->image_len = 0;
462 	}
463 }
464 EXPORT_SYMBOL(gspca_frame_add);
465 
destroy_urbs(struct gspca_dev * gspca_dev)466 static void destroy_urbs(struct gspca_dev *gspca_dev)
467 {
468 	struct urb *urb;
469 	unsigned int i;
470 
471 	gspca_dbg(gspca_dev, D_STREAM, "kill transfer\n");
472 
473 	/* Killing all URBs guarantee that no URB completion
474 	 * handler is running. Therefore, there shouldn't
475 	 * be anyone trying to access gspca_dev->urb[i]
476 	 */
477 	for (i = 0; i < MAX_NURBS; i++)
478 		usb_kill_urb(gspca_dev->urb[i]);
479 
480 	gspca_dbg(gspca_dev, D_STREAM, "releasing urbs\n");
481 	for (i = 0; i < MAX_NURBS; i++) {
482 		urb = gspca_dev->urb[i];
483 		if (!urb)
484 			continue;
485 		gspca_dev->urb[i] = NULL;
486 		usb_free_coherent(gspca_dev->dev,
487 				  urb->transfer_buffer_length,
488 				  urb->transfer_buffer,
489 				  urb->transfer_dma);
490 		usb_free_urb(urb);
491 	}
492 }
493 
gspca_set_alt0(struct gspca_dev * gspca_dev)494 static int gspca_set_alt0(struct gspca_dev *gspca_dev)
495 {
496 	int ret;
497 
498 	if (gspca_dev->alt == 0)
499 		return 0;
500 	ret = usb_set_interface(gspca_dev->dev, gspca_dev->iface, 0);
501 	if (ret < 0)
502 		pr_err("set alt 0 err %d\n", ret);
503 	return ret;
504 }
505 
506 /*
507  * look for an input transfer endpoint in an alternate setting.
508  *
509  * If xfer_ep is invalid, return the first valid ep found, otherwise
510  * look for exactly the ep with address equal to xfer_ep.
511  */
alt_xfer(struct usb_host_interface * alt,int xfer,int xfer_ep)512 static struct usb_host_endpoint *alt_xfer(struct usb_host_interface *alt,
513 					  int xfer, int xfer_ep)
514 {
515 	struct usb_host_endpoint *ep;
516 	int i, attr;
517 
518 	for (i = 0; i < alt->desc.bNumEndpoints; i++) {
519 		ep = &alt->endpoint[i];
520 		attr = ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
521 		if (attr == xfer
522 		    && ep->desc.wMaxPacketSize != 0
523 		    && usb_endpoint_dir_in(&ep->desc)
524 		    && (xfer_ep < 0 || ep->desc.bEndpointAddress == xfer_ep))
525 			return ep;
526 	}
527 	return NULL;
528 }
529 
530 /* compute the minimum bandwidth for the current transfer */
which_bandwidth(struct gspca_dev * gspca_dev)531 static u32 which_bandwidth(struct gspca_dev *gspca_dev)
532 {
533 	u32 bandwidth;
534 
535 	/* get the (max) image size */
536 	bandwidth = gspca_dev->pixfmt.sizeimage;
537 
538 	/* if the image is compressed, estimate its mean size */
539 	if (!gspca_dev->cam.needs_full_bandwidth &&
540 	    bandwidth < gspca_dev->pixfmt.width *
541 				gspca_dev->pixfmt.height)
542 		bandwidth = bandwidth * 3 / 8;	/* 0.375 */
543 
544 	/* estimate the frame rate */
545 	if (gspca_dev->sd_desc->get_streamparm) {
546 		struct v4l2_streamparm parm;
547 
548 		gspca_dev->sd_desc->get_streamparm(gspca_dev, &parm);
549 		bandwidth *= parm.parm.capture.timeperframe.denominator;
550 		bandwidth /= parm.parm.capture.timeperframe.numerator;
551 	} else {
552 
553 		/* don't hope more than 15 fps with USB 1.1 and
554 		 * image resolution >= 640x480 */
555 		if (gspca_dev->pixfmt.width >= 640
556 		 && gspca_dev->dev->speed == USB_SPEED_FULL)
557 			bandwidth *= 15;		/* 15 fps */
558 		else
559 			bandwidth *= 30;		/* 30 fps */
560 	}
561 
562 	gspca_dbg(gspca_dev, D_STREAM, "min bandwidth: %d\n", bandwidth);
563 	return bandwidth;
564 }
565 
566 /* endpoint table */
567 #define MAX_ALT 16
568 struct ep_tb_s {
569 	u32 alt;
570 	u32 bandwidth;
571 };
572 
573 /*
574  * build the table of the endpoints
575  * and compute the minimum bandwidth for the image transfer
576  */
build_isoc_ep_tb(struct gspca_dev * gspca_dev,struct usb_interface * intf,struct ep_tb_s * ep_tb)577 static int build_isoc_ep_tb(struct gspca_dev *gspca_dev,
578 			struct usb_interface *intf,
579 			struct ep_tb_s *ep_tb)
580 {
581 	struct usb_host_endpoint *ep;
582 	int i, j, nbalt, psize, found;
583 	u32 bandwidth, last_bw;
584 
585 	nbalt = intf->num_altsetting;
586 	if (nbalt > MAX_ALT)
587 		nbalt = MAX_ALT;	/* fixme: should warn */
588 
589 	/* build the endpoint table */
590 	i = 0;
591 	last_bw = 0;
592 	for (;;) {
593 		ep_tb->bandwidth = 2000 * 2000 * 120;
594 		found = 0;
595 		for (j = 0; j < nbalt; j++) {
596 			ep = alt_xfer(&intf->altsetting[j],
597 				      USB_ENDPOINT_XFER_ISOC,
598 				      gspca_dev->xfer_ep);
599 			if (ep == NULL)
600 				continue;
601 			if (ep->desc.bInterval == 0) {
602 				pr_err("alt %d iso endp with 0 interval\n", j);
603 				continue;
604 			}
605 			psize = le16_to_cpu(ep->desc.wMaxPacketSize);
606 			psize = (psize & 0x07ff) * (1 + ((psize >> 11) & 3));
607 			bandwidth = psize * 1000;
608 			if (gspca_dev->dev->speed == USB_SPEED_HIGH
609 			 || gspca_dev->dev->speed >= USB_SPEED_SUPER)
610 				bandwidth *= 8;
611 			bandwidth /= 1 << (ep->desc.bInterval - 1);
612 			if (bandwidth <= last_bw)
613 				continue;
614 			if (bandwidth < ep_tb->bandwidth) {
615 				ep_tb->bandwidth = bandwidth;
616 				ep_tb->alt = j;
617 				found = 1;
618 			}
619 		}
620 		if (!found)
621 			break;
622 		gspca_dbg(gspca_dev, D_STREAM, "alt %d bandwidth %d\n",
623 			  ep_tb->alt, ep_tb->bandwidth);
624 		last_bw = ep_tb->bandwidth;
625 		i++;
626 		ep_tb++;
627 	}
628 
629 	/*
630 	 * If the camera:
631 	 * has a usb audio class interface (a built in usb mic); and
632 	 * is a usb 1 full speed device; and
633 	 * uses the max full speed iso bandwidth; and
634 	 * and has more than 1 alt setting
635 	 * then skip the highest alt setting to spare bandwidth for the mic
636 	 */
637 	if (gspca_dev->audio &&
638 			gspca_dev->dev->speed == USB_SPEED_FULL &&
639 			last_bw >= 1000000 &&
640 			i > 1) {
641 		gspca_dbg(gspca_dev, D_STREAM, "dev has usb audio, skipping highest alt\n");
642 		i--;
643 		ep_tb--;
644 	}
645 
646 	/* get the requested bandwidth and start at the highest atlsetting */
647 	bandwidth = which_bandwidth(gspca_dev);
648 	ep_tb--;
649 	while (i > 1) {
650 		ep_tb--;
651 		if (ep_tb->bandwidth < bandwidth)
652 			break;
653 		i--;
654 	}
655 	return i;
656 }
657 
658 /*
659  * create the URBs for image transfer
660  */
create_urbs(struct gspca_dev * gspca_dev,struct usb_host_endpoint * ep)661 static int create_urbs(struct gspca_dev *gspca_dev,
662 			struct usb_host_endpoint *ep)
663 {
664 	struct urb *urb;
665 	int n, nurbs, i, psize, npkt, bsize;
666 
667 	/* calculate the packet size and the number of packets */
668 	psize = le16_to_cpu(ep->desc.wMaxPacketSize);
669 
670 	if (!gspca_dev->cam.bulk) {		/* isoc */
671 
672 		/* See paragraph 5.9 / table 5-11 of the usb 2.0 spec. */
673 		if (gspca_dev->pkt_size == 0)
674 			psize = (psize & 0x07ff) * (1 + ((psize >> 11) & 3));
675 		else
676 			psize = gspca_dev->pkt_size;
677 		npkt = gspca_dev->cam.npkt;
678 		if (npkt == 0)
679 			npkt = 32;		/* default value */
680 		bsize = psize * npkt;
681 		gspca_dbg(gspca_dev, D_STREAM,
682 			  "isoc %d pkts size %d = bsize:%d\n",
683 			  npkt, psize, bsize);
684 		nurbs = DEF_NURBS;
685 	} else {				/* bulk */
686 		npkt = 0;
687 		bsize = gspca_dev->cam.bulk_size;
688 		if (bsize == 0)
689 			bsize = psize;
690 		gspca_dbg(gspca_dev, D_STREAM, "bulk bsize:%d\n", bsize);
691 		if (gspca_dev->cam.bulk_nurbs != 0)
692 			nurbs = gspca_dev->cam.bulk_nurbs;
693 		else
694 			nurbs = 1;
695 	}
696 
697 	for (n = 0; n < nurbs; n++) {
698 		urb = usb_alloc_urb(npkt, GFP_KERNEL);
699 		if (!urb)
700 			return -ENOMEM;
701 		gspca_dev->urb[n] = urb;
702 		urb->transfer_buffer = usb_alloc_coherent(gspca_dev->dev,
703 						bsize,
704 						GFP_KERNEL,
705 						&urb->transfer_dma);
706 
707 		if (urb->transfer_buffer == NULL) {
708 			pr_err("usb_alloc_coherent failed\n");
709 			return -ENOMEM;
710 		}
711 		urb->dev = gspca_dev->dev;
712 		urb->context = gspca_dev;
713 		urb->transfer_buffer_length = bsize;
714 		if (npkt != 0) {		/* ISOC */
715 			urb->pipe = usb_rcvisocpipe(gspca_dev->dev,
716 						    ep->desc.bEndpointAddress);
717 			urb->transfer_flags = URB_ISO_ASAP
718 					| URB_NO_TRANSFER_DMA_MAP;
719 			urb->interval = 1 << (ep->desc.bInterval - 1);
720 			urb->complete = isoc_irq;
721 			urb->number_of_packets = npkt;
722 			for (i = 0; i < npkt; i++) {
723 				urb->iso_frame_desc[i].length = psize;
724 				urb->iso_frame_desc[i].offset = psize * i;
725 			}
726 		} else {		/* bulk */
727 			urb->pipe = usb_rcvbulkpipe(gspca_dev->dev,
728 						ep->desc.bEndpointAddress);
729 			urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
730 			urb->complete = bulk_irq;
731 		}
732 	}
733 	return 0;
734 }
735 
736 /* Note: both the queue and the usb locks should be held when calling this */
gspca_stream_off(struct gspca_dev * gspca_dev)737 static void gspca_stream_off(struct gspca_dev *gspca_dev)
738 {
739 	gspca_dev->streaming = false;
740 	gspca_dev->usb_err = 0;
741 	if (gspca_dev->sd_desc->stopN)
742 		gspca_dev->sd_desc->stopN(gspca_dev);
743 	destroy_urbs(gspca_dev);
744 	gspca_input_destroy_urb(gspca_dev);
745 	gspca_set_alt0(gspca_dev);
746 	if (gspca_dev->present)
747 		gspca_input_create_urb(gspca_dev);
748 	if (gspca_dev->sd_desc->stop0)
749 		gspca_dev->sd_desc->stop0(gspca_dev);
750 	gspca_dbg(gspca_dev, D_STREAM, "stream off OK\n");
751 }
752 
753 /*
754  * start the USB transfer
755  */
gspca_init_transfer(struct gspca_dev * gspca_dev)756 static int gspca_init_transfer(struct gspca_dev *gspca_dev)
757 {
758 	struct usb_interface *intf;
759 	struct usb_host_endpoint *ep;
760 	struct urb *urb;
761 	struct ep_tb_s ep_tb[MAX_ALT];
762 	int n, ret, xfer, alt, alt_idx;
763 
764 	/* reset the streaming variables */
765 	gspca_dev->image = NULL;
766 	gspca_dev->image_len = 0;
767 	gspca_dev->last_packet_type = DISCARD_PACKET;
768 
769 	gspca_dev->usb_err = 0;
770 
771 	/* do the specific subdriver stuff before endpoint selection */
772 	intf = usb_ifnum_to_if(gspca_dev->dev, gspca_dev->iface);
773 	gspca_dev->alt = gspca_dev->cam.bulk ? intf->num_altsetting : 0;
774 	if (gspca_dev->sd_desc->isoc_init) {
775 		ret = gspca_dev->sd_desc->isoc_init(gspca_dev);
776 		if (ret < 0)
777 			return ret;
778 	}
779 	xfer = gspca_dev->cam.bulk ? USB_ENDPOINT_XFER_BULK
780 				   : USB_ENDPOINT_XFER_ISOC;
781 
782 	/* if bulk or the subdriver forced an altsetting, get the endpoint */
783 	if (gspca_dev->alt != 0) {
784 		gspca_dev->alt--;	/* (previous version compatibility) */
785 		ep = alt_xfer(&intf->altsetting[gspca_dev->alt], xfer,
786 			      gspca_dev->xfer_ep);
787 		if (ep == NULL) {
788 			pr_err("bad altsetting %d\n", gspca_dev->alt);
789 			return -EIO;
790 		}
791 		ep_tb[0].alt = gspca_dev->alt;
792 		alt_idx = 1;
793 	} else {
794 		/* else, compute the minimum bandwidth
795 		 * and build the endpoint table */
796 		alt_idx = build_isoc_ep_tb(gspca_dev, intf, ep_tb);
797 		if (alt_idx <= 0) {
798 			pr_err("no transfer endpoint found\n");
799 			return -EIO;
800 		}
801 	}
802 
803 	/* set the highest alternate setting and
804 	 * loop until urb submit succeeds */
805 	gspca_input_destroy_urb(gspca_dev);
806 
807 	gspca_dev->alt = ep_tb[--alt_idx].alt;
808 	alt = -1;
809 	for (;;) {
810 		if (alt != gspca_dev->alt) {
811 			alt = gspca_dev->alt;
812 			if (intf->num_altsetting > 1) {
813 				ret = usb_set_interface(gspca_dev->dev,
814 							gspca_dev->iface,
815 							alt);
816 				if (ret < 0) {
817 					if (ret == -ENOSPC)
818 						goto retry; /*fixme: ugly*/
819 					pr_err("set alt %d err %d\n", alt, ret);
820 					goto out;
821 				}
822 			}
823 		}
824 		if (!gspca_dev->cam.no_urb_create) {
825 			gspca_dbg(gspca_dev, D_STREAM, "init transfer alt %d\n",
826 				  alt);
827 			ret = create_urbs(gspca_dev,
828 				alt_xfer(&intf->altsetting[alt], xfer,
829 					 gspca_dev->xfer_ep));
830 			if (ret < 0) {
831 				destroy_urbs(gspca_dev);
832 				goto out;
833 			}
834 		}
835 
836 		/* clear the bulk endpoint */
837 		if (gspca_dev->cam.bulk)
838 			usb_clear_halt(gspca_dev->dev,
839 					gspca_dev->urb[0]->pipe);
840 
841 		/* start the cam */
842 		ret = gspca_dev->sd_desc->start(gspca_dev);
843 		if (ret < 0) {
844 			destroy_urbs(gspca_dev);
845 			goto out;
846 		}
847 		v4l2_ctrl_handler_setup(gspca_dev->vdev.ctrl_handler);
848 		gspca_dev->streaming = true;
849 
850 		/* some bulk transfers are started by the subdriver */
851 		if (gspca_dev->cam.bulk && gspca_dev->cam.bulk_nurbs == 0)
852 			break;
853 
854 		/* submit the URBs */
855 		for (n = 0; n < MAX_NURBS; n++) {
856 			urb = gspca_dev->urb[n];
857 			if (urb == NULL)
858 				break;
859 			ret = usb_submit_urb(urb, GFP_KERNEL);
860 			if (ret < 0)
861 				break;
862 		}
863 		if (ret >= 0)
864 			break;			/* transfer is started */
865 
866 		/* something when wrong
867 		 * stop the webcam and free the transfer resources */
868 		gspca_stream_off(gspca_dev);
869 		if (ret != -ENOSPC) {
870 			pr_err("usb_submit_urb alt %d err %d\n",
871 			       gspca_dev->alt, ret);
872 			goto out;
873 		}
874 
875 		/* the bandwidth is not wide enough
876 		 * negotiate or try a lower alternate setting */
877 retry:
878 		gspca_err(gspca_dev, "alt %d - bandwidth not wide enough, trying again\n",
879 			  alt);
880 		msleep(20);	/* wait for kill complete */
881 		if (gspca_dev->sd_desc->isoc_nego) {
882 			ret = gspca_dev->sd_desc->isoc_nego(gspca_dev);
883 			if (ret < 0)
884 				goto out;
885 		} else {
886 			if (alt_idx <= 0) {
887 				pr_err("no transfer endpoint found\n");
888 				ret = -EIO;
889 				goto out;
890 			}
891 			gspca_dev->alt = ep_tb[--alt_idx].alt;
892 		}
893 	}
894 out:
895 	gspca_input_create_urb(gspca_dev);
896 	return ret;
897 }
898 
gspca_set_default_mode(struct gspca_dev * gspca_dev)899 static void gspca_set_default_mode(struct gspca_dev *gspca_dev)
900 {
901 	int i;
902 
903 	i = gspca_dev->cam.nmodes - 1;	/* take the highest mode */
904 	gspca_dev->curr_mode = i;
905 	gspca_dev->pixfmt = gspca_dev->cam.cam_mode[i];
906 
907 	/* does nothing if ctrl_handler == NULL */
908 	v4l2_ctrl_handler_setup(gspca_dev->vdev.ctrl_handler);
909 }
910 
wxh_to_mode(struct gspca_dev * gspca_dev,int width,int height,u32 pixelformat)911 static int wxh_to_mode(struct gspca_dev *gspca_dev,
912 			int width, int height, u32 pixelformat)
913 {
914 	int i;
915 
916 	for (i = 0; i < gspca_dev->cam.nmodes; i++) {
917 		if (width == gspca_dev->cam.cam_mode[i].width
918 		    && height == gspca_dev->cam.cam_mode[i].height
919 		    && pixelformat == gspca_dev->cam.cam_mode[i].pixelformat)
920 			return i;
921 	}
922 	return -EINVAL;
923 }
924 
wxh_to_nearest_mode(struct gspca_dev * gspca_dev,int width,int height,u32 pixelformat)925 static int wxh_to_nearest_mode(struct gspca_dev *gspca_dev,
926 			int width, int height, u32 pixelformat)
927 {
928 	int i;
929 
930 	for (i = gspca_dev->cam.nmodes; --i >= 0; ) {
931 		if (width >= gspca_dev->cam.cam_mode[i].width
932 		    && height >= gspca_dev->cam.cam_mode[i].height
933 		    && pixelformat == gspca_dev->cam.cam_mode[i].pixelformat)
934 			return i;
935 	}
936 	for (i = gspca_dev->cam.nmodes; --i > 0; ) {
937 		if (width >= gspca_dev->cam.cam_mode[i].width
938 		    && height >= gspca_dev->cam.cam_mode[i].height)
939 			break;
940 	}
941 	return i;
942 }
943 
944 /*
945  * search a mode with the right pixel format
946  */
gspca_get_mode(struct gspca_dev * gspca_dev,int mode,int pixfmt)947 static int gspca_get_mode(struct gspca_dev *gspca_dev,
948 			int mode,
949 			int pixfmt)
950 {
951 	int modeU, modeD;
952 
953 	modeU = modeD = mode;
954 	while ((modeU < gspca_dev->cam.nmodes) || modeD >= 0) {
955 		if (--modeD >= 0) {
956 			if (gspca_dev->cam.cam_mode[modeD].pixelformat
957 								== pixfmt)
958 				return modeD;
959 		}
960 		if (++modeU < gspca_dev->cam.nmodes) {
961 			if (gspca_dev->cam.cam_mode[modeU].pixelformat
962 								== pixfmt)
963 				return modeU;
964 		}
965 	}
966 	return -EINVAL;
967 }
968 
969 #ifdef CONFIG_VIDEO_ADV_DEBUG
vidioc_g_chip_info(struct file * file,void * priv,struct v4l2_dbg_chip_info * chip)970 static int vidioc_g_chip_info(struct file *file, void *priv,
971 				struct v4l2_dbg_chip_info *chip)
972 {
973 	struct gspca_dev *gspca_dev = video_drvdata(file);
974 
975 	gspca_dev->usb_err = 0;
976 	if (gspca_dev->sd_desc->get_chip_info)
977 		return gspca_dev->sd_desc->get_chip_info(gspca_dev, chip);
978 	return chip->match.addr ? -EINVAL : 0;
979 }
980 
vidioc_g_register(struct file * file,void * priv,struct v4l2_dbg_register * reg)981 static int vidioc_g_register(struct file *file, void *priv,
982 		struct v4l2_dbg_register *reg)
983 {
984 	struct gspca_dev *gspca_dev = video_drvdata(file);
985 
986 	gspca_dev->usb_err = 0;
987 	return gspca_dev->sd_desc->get_register(gspca_dev, reg);
988 }
989 
vidioc_s_register(struct file * file,void * priv,const struct v4l2_dbg_register * reg)990 static int vidioc_s_register(struct file *file, void *priv,
991 		const struct v4l2_dbg_register *reg)
992 {
993 	struct gspca_dev *gspca_dev = video_drvdata(file);
994 
995 	gspca_dev->usb_err = 0;
996 	return gspca_dev->sd_desc->set_register(gspca_dev, reg);
997 }
998 #endif
999 
vidioc_enum_fmt_vid_cap(struct file * file,void * priv,struct v4l2_fmtdesc * fmtdesc)1000 static int vidioc_enum_fmt_vid_cap(struct file *file, void  *priv,
1001 				struct v4l2_fmtdesc *fmtdesc)
1002 {
1003 	struct gspca_dev *gspca_dev = video_drvdata(file);
1004 	int i, j, index;
1005 	__u32 fmt_tb[8];
1006 
1007 	/* give an index to each format */
1008 	index = 0;
1009 	for (i = gspca_dev->cam.nmodes; --i >= 0; ) {
1010 		fmt_tb[index] = gspca_dev->cam.cam_mode[i].pixelformat;
1011 		j = 0;
1012 		for (;;) {
1013 			if (fmt_tb[j] == fmt_tb[index])
1014 				break;
1015 			j++;
1016 		}
1017 		if (j == index) {
1018 			if (fmtdesc->index == index)
1019 				break;		/* new format */
1020 			index++;
1021 			if (index >= ARRAY_SIZE(fmt_tb))
1022 				return -EINVAL;
1023 		}
1024 	}
1025 	if (i < 0)
1026 		return -EINVAL;		/* no more format */
1027 
1028 	fmtdesc->pixelformat = fmt_tb[index];
1029 	return 0;
1030 }
1031 
vidioc_g_fmt_vid_cap(struct file * file,void * _priv,struct v4l2_format * fmt)1032 static int vidioc_g_fmt_vid_cap(struct file *file, void *_priv,
1033 				struct v4l2_format *fmt)
1034 {
1035 	struct gspca_dev *gspca_dev = video_drvdata(file);
1036 	u32 priv = fmt->fmt.pix.priv;
1037 
1038 	fmt->fmt.pix = gspca_dev->pixfmt;
1039 	/* some drivers use priv internally, so keep the original value */
1040 	fmt->fmt.pix.priv = priv;
1041 	return 0;
1042 }
1043 
try_fmt_vid_cap(struct gspca_dev * gspca_dev,struct v4l2_format * fmt)1044 static int try_fmt_vid_cap(struct gspca_dev *gspca_dev,
1045 			struct v4l2_format *fmt)
1046 {
1047 	int w, h, mode, mode2;
1048 
1049 	w = fmt->fmt.pix.width;
1050 	h = fmt->fmt.pix.height;
1051 
1052 	PDEBUG_MODE(gspca_dev, D_CONF, "try fmt cap",
1053 		    fmt->fmt.pix.pixelformat, w, h);
1054 
1055 	/* search the nearest mode for width and height */
1056 	mode = wxh_to_nearest_mode(gspca_dev, w, h, fmt->fmt.pix.pixelformat);
1057 
1058 	/* OK if right palette */
1059 	if (gspca_dev->cam.cam_mode[mode].pixelformat
1060 						!= fmt->fmt.pix.pixelformat) {
1061 
1062 		/* else, search the closest mode with the same pixel format */
1063 		mode2 = gspca_get_mode(gspca_dev, mode,
1064 					fmt->fmt.pix.pixelformat);
1065 		if (mode2 >= 0)
1066 			mode = mode2;
1067 	}
1068 	fmt->fmt.pix = gspca_dev->cam.cam_mode[mode];
1069 	if (gspca_dev->sd_desc->try_fmt) {
1070 		/* pass original resolution to subdriver try_fmt */
1071 		fmt->fmt.pix.width = w;
1072 		fmt->fmt.pix.height = h;
1073 		gspca_dev->sd_desc->try_fmt(gspca_dev, fmt);
1074 	}
1075 	return mode;			/* used when s_fmt */
1076 }
1077 
vidioc_try_fmt_vid_cap(struct file * file,void * _priv,struct v4l2_format * fmt)1078 static int vidioc_try_fmt_vid_cap(struct file *file, void *_priv,
1079 				  struct v4l2_format *fmt)
1080 {
1081 	struct gspca_dev *gspca_dev = video_drvdata(file);
1082 	u32 priv = fmt->fmt.pix.priv;
1083 
1084 	if (try_fmt_vid_cap(gspca_dev, fmt) < 0)
1085 		return -EINVAL;
1086 	/* some drivers use priv internally, so keep the original value */
1087 	fmt->fmt.pix.priv = priv;
1088 	return 0;
1089 }
1090 
vidioc_s_fmt_vid_cap(struct file * file,void * _priv,struct v4l2_format * fmt)1091 static int vidioc_s_fmt_vid_cap(struct file *file, void *_priv,
1092 				struct v4l2_format *fmt)
1093 {
1094 	struct gspca_dev *gspca_dev = video_drvdata(file);
1095 	u32 priv = fmt->fmt.pix.priv;
1096 	int mode;
1097 
1098 	if (vb2_is_busy(&gspca_dev->queue))
1099 		return -EBUSY;
1100 
1101 	mode = try_fmt_vid_cap(gspca_dev, fmt);
1102 	if (mode < 0)
1103 		return -EINVAL;
1104 
1105 	gspca_dev->curr_mode = mode;
1106 	if (gspca_dev->sd_desc->try_fmt)
1107 		/* subdriver try_fmt can modify format parameters */
1108 		gspca_dev->pixfmt = fmt->fmt.pix;
1109 	else
1110 		gspca_dev->pixfmt = gspca_dev->cam.cam_mode[mode];
1111 	/* some drivers use priv internally, so keep the original value */
1112 	fmt->fmt.pix.priv = priv;
1113 	return 0;
1114 }
1115 
vidioc_enum_framesizes(struct file * file,void * priv,struct v4l2_frmsizeenum * fsize)1116 static int vidioc_enum_framesizes(struct file *file, void *priv,
1117 				  struct v4l2_frmsizeenum *fsize)
1118 {
1119 	struct gspca_dev *gspca_dev = video_drvdata(file);
1120 	int i;
1121 	__u32 index = 0;
1122 
1123 	if (gspca_dev->sd_desc->enum_framesizes)
1124 		return gspca_dev->sd_desc->enum_framesizes(gspca_dev, fsize);
1125 
1126 	for (i = 0; i < gspca_dev->cam.nmodes; i++) {
1127 		if (fsize->pixel_format !=
1128 				gspca_dev->cam.cam_mode[i].pixelformat)
1129 			continue;
1130 
1131 		if (fsize->index == index) {
1132 			fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
1133 			fsize->discrete.width =
1134 				gspca_dev->cam.cam_mode[i].width;
1135 			fsize->discrete.height =
1136 				gspca_dev->cam.cam_mode[i].height;
1137 			return 0;
1138 		}
1139 		index++;
1140 	}
1141 
1142 	return -EINVAL;
1143 }
1144 
vidioc_enum_frameintervals(struct file * filp,void * priv,struct v4l2_frmivalenum * fival)1145 static int vidioc_enum_frameintervals(struct file *filp, void *priv,
1146 				      struct v4l2_frmivalenum *fival)
1147 {
1148 	struct gspca_dev *gspca_dev = video_drvdata(filp);
1149 	int mode;
1150 	__u32 i;
1151 
1152 	mode = wxh_to_mode(gspca_dev, fival->width, fival->height,
1153 			   fival->pixel_format);
1154 	if (mode < 0)
1155 		return -EINVAL;
1156 
1157 	if (gspca_dev->cam.mode_framerates == NULL ||
1158 			gspca_dev->cam.mode_framerates[mode].nrates == 0)
1159 		return -EINVAL;
1160 
1161 	if (fival->pixel_format !=
1162 			gspca_dev->cam.cam_mode[mode].pixelformat)
1163 		return -EINVAL;
1164 
1165 	for (i = 0; i < gspca_dev->cam.mode_framerates[mode].nrates; i++) {
1166 		if (fival->index == i) {
1167 			fival->type = V4L2_FRMIVAL_TYPE_DISCRETE;
1168 			fival->discrete.numerator = 1;
1169 			fival->discrete.denominator =
1170 				gspca_dev->cam.mode_framerates[mode].rates[i];
1171 			return 0;
1172 		}
1173 	}
1174 
1175 	return -EINVAL;
1176 }
1177 
gspca_release(struct v4l2_device * v4l2_device)1178 static void gspca_release(struct v4l2_device *v4l2_device)
1179 {
1180 	struct gspca_dev *gspca_dev =
1181 		container_of(v4l2_device, struct gspca_dev, v4l2_dev);
1182 
1183 	v4l2_ctrl_handler_free(gspca_dev->vdev.ctrl_handler);
1184 	v4l2_device_unregister(&gspca_dev->v4l2_dev);
1185 	kfree(gspca_dev->usb_buf);
1186 	kfree(gspca_dev);
1187 }
1188 
vidioc_querycap(struct file * file,void * priv,struct v4l2_capability * cap)1189 static int vidioc_querycap(struct file *file, void  *priv,
1190 			   struct v4l2_capability *cap)
1191 {
1192 	struct gspca_dev *gspca_dev = video_drvdata(file);
1193 
1194 	strscpy((char *)cap->driver, gspca_dev->sd_desc->name,
1195 		sizeof(cap->driver));
1196 	if (gspca_dev->dev->product != NULL) {
1197 		strscpy((char *)cap->card, gspca_dev->dev->product,
1198 			sizeof(cap->card));
1199 	} else {
1200 		snprintf((char *) cap->card, sizeof cap->card,
1201 			"USB Camera (%04x:%04x)",
1202 			le16_to_cpu(gspca_dev->dev->descriptor.idVendor),
1203 			le16_to_cpu(gspca_dev->dev->descriptor.idProduct));
1204 	}
1205 	usb_make_path(gspca_dev->dev, (char *) cap->bus_info,
1206 			sizeof(cap->bus_info));
1207 	return 0;
1208 }
1209 
vidioc_enum_input(struct file * file,void * priv,struct v4l2_input * input)1210 static int vidioc_enum_input(struct file *file, void *priv,
1211 				struct v4l2_input *input)
1212 {
1213 	struct gspca_dev *gspca_dev = video_drvdata(file);
1214 
1215 	if (input->index != 0)
1216 		return -EINVAL;
1217 	input->type = V4L2_INPUT_TYPE_CAMERA;
1218 	input->status = gspca_dev->cam.input_flags;
1219 	strscpy(input->name, gspca_dev->sd_desc->name,
1220 		sizeof input->name);
1221 	return 0;
1222 }
1223 
vidioc_g_input(struct file * file,void * priv,unsigned int * i)1224 static int vidioc_g_input(struct file *file, void *priv, unsigned int *i)
1225 {
1226 	*i = 0;
1227 	return 0;
1228 }
1229 
vidioc_s_input(struct file * file,void * priv,unsigned int i)1230 static int vidioc_s_input(struct file *file, void *priv, unsigned int i)
1231 {
1232 	if (i > 0)
1233 		return -EINVAL;
1234 	return 0;
1235 }
1236 
vidioc_g_jpegcomp(struct file * file,void * priv,struct v4l2_jpegcompression * jpegcomp)1237 static int vidioc_g_jpegcomp(struct file *file, void *priv,
1238 			struct v4l2_jpegcompression *jpegcomp)
1239 {
1240 	struct gspca_dev *gspca_dev = video_drvdata(file);
1241 
1242 	gspca_dev->usb_err = 0;
1243 	return gspca_dev->sd_desc->get_jcomp(gspca_dev, jpegcomp);
1244 }
1245 
vidioc_s_jpegcomp(struct file * file,void * priv,const struct v4l2_jpegcompression * jpegcomp)1246 static int vidioc_s_jpegcomp(struct file *file, void *priv,
1247 			const struct v4l2_jpegcompression *jpegcomp)
1248 {
1249 	struct gspca_dev *gspca_dev = video_drvdata(file);
1250 
1251 	gspca_dev->usb_err = 0;
1252 	return gspca_dev->sd_desc->set_jcomp(gspca_dev, jpegcomp);
1253 }
1254 
vidioc_g_parm(struct file * filp,void * priv,struct v4l2_streamparm * parm)1255 static int vidioc_g_parm(struct file *filp, void *priv,
1256 			struct v4l2_streamparm *parm)
1257 {
1258 	struct gspca_dev *gspca_dev = video_drvdata(filp);
1259 
1260 	parm->parm.capture.readbuffers = gspca_dev->queue.min_buffers_needed;
1261 
1262 	if (!gspca_dev->sd_desc->get_streamparm)
1263 		return 0;
1264 
1265 	parm->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
1266 	gspca_dev->usb_err = 0;
1267 	gspca_dev->sd_desc->get_streamparm(gspca_dev, parm);
1268 	return gspca_dev->usb_err;
1269 }
1270 
vidioc_s_parm(struct file * filp,void * priv,struct v4l2_streamparm * parm)1271 static int vidioc_s_parm(struct file *filp, void *priv,
1272 			struct v4l2_streamparm *parm)
1273 {
1274 	struct gspca_dev *gspca_dev = video_drvdata(filp);
1275 
1276 	parm->parm.capture.readbuffers = gspca_dev->queue.min_buffers_needed;
1277 
1278 	if (!gspca_dev->sd_desc->set_streamparm) {
1279 		parm->parm.capture.capability = 0;
1280 		return 0;
1281 	}
1282 
1283 	parm->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
1284 	gspca_dev->usb_err = 0;
1285 	gspca_dev->sd_desc->set_streamparm(gspca_dev, parm);
1286 	return gspca_dev->usb_err;
1287 }
1288 
gspca_queue_setup(struct vb2_queue * vq,unsigned int * nbuffers,unsigned int * nplanes,unsigned int sizes[],struct device * alloc_devs[])1289 static int gspca_queue_setup(struct vb2_queue *vq,
1290 			     unsigned int *nbuffers, unsigned int *nplanes,
1291 			     unsigned int sizes[], struct device *alloc_devs[])
1292 {
1293 	struct gspca_dev *gspca_dev = vb2_get_drv_priv(vq);
1294 	unsigned int size = PAGE_ALIGN(gspca_dev->pixfmt.sizeimage);
1295 
1296 	if (*nplanes)
1297 		return sizes[0] < size ? -EINVAL : 0;
1298 	*nplanes = 1;
1299 	sizes[0] = size;
1300 	return 0;
1301 }
1302 
gspca_buffer_prepare(struct vb2_buffer * vb)1303 static int gspca_buffer_prepare(struct vb2_buffer *vb)
1304 {
1305 	struct gspca_dev *gspca_dev = vb2_get_drv_priv(vb->vb2_queue);
1306 	unsigned long size = PAGE_ALIGN(gspca_dev->pixfmt.sizeimage);
1307 
1308 	if (vb2_plane_size(vb, 0) < size) {
1309 		gspca_err(gspca_dev, "buffer too small (%lu < %lu)\n",
1310 			 vb2_plane_size(vb, 0), size);
1311 		return -EINVAL;
1312 	}
1313 	return 0;
1314 }
1315 
gspca_buffer_finish(struct vb2_buffer * vb)1316 static void gspca_buffer_finish(struct vb2_buffer *vb)
1317 {
1318 	struct gspca_dev *gspca_dev = vb2_get_drv_priv(vb->vb2_queue);
1319 
1320 	if (!gspca_dev->sd_desc->dq_callback)
1321 		return;
1322 
1323 	gspca_dev->usb_err = 0;
1324 	if (gspca_dev->present)
1325 		gspca_dev->sd_desc->dq_callback(gspca_dev);
1326 }
1327 
gspca_buffer_queue(struct vb2_buffer * vb)1328 static void gspca_buffer_queue(struct vb2_buffer *vb)
1329 {
1330 	struct gspca_dev *gspca_dev = vb2_get_drv_priv(vb->vb2_queue);
1331 	struct gspca_buffer *buf = to_gspca_buffer(vb);
1332 	unsigned long flags;
1333 
1334 	spin_lock_irqsave(&gspca_dev->qlock, flags);
1335 	list_add_tail(&buf->list, &gspca_dev->buf_list);
1336 	spin_unlock_irqrestore(&gspca_dev->qlock, flags);
1337 }
1338 
gspca_return_all_buffers(struct gspca_dev * gspca_dev,enum vb2_buffer_state state)1339 static void gspca_return_all_buffers(struct gspca_dev *gspca_dev,
1340 				     enum vb2_buffer_state state)
1341 {
1342 	struct gspca_buffer *buf, *node;
1343 	unsigned long flags;
1344 
1345 	spin_lock_irqsave(&gspca_dev->qlock, flags);
1346 	list_for_each_entry_safe(buf, node, &gspca_dev->buf_list, list) {
1347 		vb2_buffer_done(&buf->vb.vb2_buf, state);
1348 		list_del(&buf->list);
1349 	}
1350 	spin_unlock_irqrestore(&gspca_dev->qlock, flags);
1351 }
1352 
gspca_start_streaming(struct vb2_queue * vq,unsigned int count)1353 static int gspca_start_streaming(struct vb2_queue *vq, unsigned int count)
1354 {
1355 	struct gspca_dev *gspca_dev = vb2_get_drv_priv(vq);
1356 	int ret;
1357 
1358 	gspca_dev->sequence = 0;
1359 
1360 	ret = gspca_init_transfer(gspca_dev);
1361 	if (ret)
1362 		gspca_return_all_buffers(gspca_dev, VB2_BUF_STATE_QUEUED);
1363 	return ret;
1364 }
1365 
gspca_stop_streaming(struct vb2_queue * vq)1366 static void gspca_stop_streaming(struct vb2_queue *vq)
1367 {
1368 	struct gspca_dev *gspca_dev = vb2_get_drv_priv(vq);
1369 
1370 	gspca_stream_off(gspca_dev);
1371 
1372 	/* Release all active buffers */
1373 	gspca_return_all_buffers(gspca_dev, VB2_BUF_STATE_ERROR);
1374 }
1375 
1376 static const struct vb2_ops gspca_qops = {
1377 	.queue_setup		= gspca_queue_setup,
1378 	.buf_prepare		= gspca_buffer_prepare,
1379 	.buf_finish		= gspca_buffer_finish,
1380 	.buf_queue		= gspca_buffer_queue,
1381 	.start_streaming	= gspca_start_streaming,
1382 	.stop_streaming		= gspca_stop_streaming,
1383 	.wait_prepare		= vb2_ops_wait_prepare,
1384 	.wait_finish		= vb2_ops_wait_finish,
1385 };
1386 
1387 static const struct v4l2_file_operations dev_fops = {
1388 	.owner = THIS_MODULE,
1389 	.open = v4l2_fh_open,
1390 	.release = vb2_fop_release,
1391 	.unlocked_ioctl = video_ioctl2,
1392 	.read = vb2_fop_read,
1393 	.mmap = vb2_fop_mmap,
1394 	.poll = vb2_fop_poll,
1395 };
1396 
1397 static const struct v4l2_ioctl_ops dev_ioctl_ops = {
1398 	.vidioc_querycap	= vidioc_querycap,
1399 	.vidioc_enum_fmt_vid_cap = vidioc_enum_fmt_vid_cap,
1400 	.vidioc_try_fmt_vid_cap	= vidioc_try_fmt_vid_cap,
1401 	.vidioc_g_fmt_vid_cap	= vidioc_g_fmt_vid_cap,
1402 	.vidioc_s_fmt_vid_cap	= vidioc_s_fmt_vid_cap,
1403 	.vidioc_enum_input	= vidioc_enum_input,
1404 	.vidioc_g_input		= vidioc_g_input,
1405 	.vidioc_s_input		= vidioc_s_input,
1406 	.vidioc_g_jpegcomp	= vidioc_g_jpegcomp,
1407 	.vidioc_s_jpegcomp	= vidioc_s_jpegcomp,
1408 	.vidioc_g_parm		= vidioc_g_parm,
1409 	.vidioc_s_parm		= vidioc_s_parm,
1410 	.vidioc_enum_framesizes = vidioc_enum_framesizes,
1411 	.vidioc_enum_frameintervals = vidioc_enum_frameintervals,
1412 
1413 	.vidioc_reqbufs		= vb2_ioctl_reqbufs,
1414 	.vidioc_create_bufs	= vb2_ioctl_create_bufs,
1415 	.vidioc_querybuf	= vb2_ioctl_querybuf,
1416 	.vidioc_qbuf		= vb2_ioctl_qbuf,
1417 	.vidioc_dqbuf		= vb2_ioctl_dqbuf,
1418 	.vidioc_expbuf		= vb2_ioctl_expbuf,
1419 	.vidioc_streamon	= vb2_ioctl_streamon,
1420 	.vidioc_streamoff	= vb2_ioctl_streamoff,
1421 
1422 #ifdef CONFIG_VIDEO_ADV_DEBUG
1423 	.vidioc_g_chip_info	= vidioc_g_chip_info,
1424 	.vidioc_g_register	= vidioc_g_register,
1425 	.vidioc_s_register	= vidioc_s_register,
1426 #endif
1427 	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
1428 	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
1429 };
1430 
1431 static const struct video_device gspca_template = {
1432 	.name = "gspca main driver",
1433 	.fops = &dev_fops,
1434 	.ioctl_ops = &dev_ioctl_ops,
1435 	.release = video_device_release_empty, /* We use v4l2_dev.release */
1436 };
1437 
1438 /*
1439  * probe and create a new gspca device
1440  *
1441  * This function must be called by the sub-driver when it is
1442  * called for probing a new device.
1443  */
gspca_dev_probe2(struct usb_interface * intf,const struct usb_device_id * id,const struct sd_desc * sd_desc,int dev_size,struct module * module)1444 int gspca_dev_probe2(struct usb_interface *intf,
1445 		const struct usb_device_id *id,
1446 		const struct sd_desc *sd_desc,
1447 		int dev_size,
1448 		struct module *module)
1449 {
1450 	struct gspca_dev *gspca_dev;
1451 	struct usb_device *dev = interface_to_usbdev(intf);
1452 	struct vb2_queue *q;
1453 	int ret;
1454 
1455 	pr_info("%s-" GSPCA_VERSION " probing %04x:%04x\n",
1456 		sd_desc->name, id->idVendor, id->idProduct);
1457 
1458 	/* create the device */
1459 	if (dev_size < sizeof *gspca_dev)
1460 		dev_size = sizeof *gspca_dev;
1461 	gspca_dev = kzalloc(dev_size, GFP_KERNEL);
1462 	if (!gspca_dev) {
1463 		pr_err("couldn't kzalloc gspca struct\n");
1464 		return -ENOMEM;
1465 	}
1466 	gspca_dev->usb_buf = kzalloc(USB_BUF_SZ, GFP_KERNEL);
1467 	if (!gspca_dev->usb_buf) {
1468 		pr_err("out of memory\n");
1469 		ret = -ENOMEM;
1470 		goto out;
1471 	}
1472 	gspca_dev->dev = dev;
1473 	gspca_dev->iface = intf->cur_altsetting->desc.bInterfaceNumber;
1474 	gspca_dev->xfer_ep = -1;
1475 
1476 	/* check if any audio device */
1477 	if (dev->actconfig->desc.bNumInterfaces != 1) {
1478 		int i;
1479 		struct usb_interface *intf2;
1480 
1481 		for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) {
1482 			intf2 = dev->actconfig->interface[i];
1483 			if (intf2 != NULL
1484 			 && intf2->altsetting != NULL
1485 			 && intf2->altsetting->desc.bInterfaceClass ==
1486 					 USB_CLASS_AUDIO) {
1487 				gspca_dev->audio = 1;
1488 				break;
1489 			}
1490 		}
1491 	}
1492 
1493 	gspca_dev->v4l2_dev.release = gspca_release;
1494 	ret = v4l2_device_register(&intf->dev, &gspca_dev->v4l2_dev);
1495 	if (ret)
1496 		goto out;
1497 	gspca_dev->present = true;
1498 	gspca_dev->sd_desc = sd_desc;
1499 	gspca_dev->empty_packet = -1;	/* don't check the empty packets */
1500 	gspca_dev->vdev = gspca_template;
1501 	gspca_dev->vdev.v4l2_dev = &gspca_dev->v4l2_dev;
1502 	gspca_dev->vdev.device_caps = V4L2_CAP_VIDEO_CAPTURE |
1503 				      V4L2_CAP_STREAMING | V4L2_CAP_READWRITE;
1504 	video_set_drvdata(&gspca_dev->vdev, gspca_dev);
1505 	gspca_dev->module = module;
1506 
1507 	mutex_init(&gspca_dev->usb_lock);
1508 	gspca_dev->vdev.lock = &gspca_dev->usb_lock;
1509 	init_waitqueue_head(&gspca_dev->wq);
1510 
1511 	/* Initialize the vb2 queue */
1512 	q = &gspca_dev->queue;
1513 	q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
1514 	q->io_modes = VB2_MMAP | VB2_USERPTR | VB2_DMABUF | VB2_READ;
1515 	q->drv_priv = gspca_dev;
1516 	q->buf_struct_size = sizeof(struct gspca_buffer);
1517 	q->ops = &gspca_qops;
1518 	q->mem_ops = &vb2_vmalloc_memops;
1519 	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
1520 	q->min_buffers_needed = 2;
1521 	q->lock = &gspca_dev->usb_lock;
1522 	ret = vb2_queue_init(q);
1523 	if (ret)
1524 		goto out;
1525 	gspca_dev->vdev.queue = q;
1526 
1527 	INIT_LIST_HEAD(&gspca_dev->buf_list);
1528 	spin_lock_init(&gspca_dev->qlock);
1529 
1530 	/* configure the subdriver and initialize the USB device */
1531 	ret = sd_desc->config(gspca_dev, id);
1532 	if (ret < 0)
1533 		goto out;
1534 	ret = sd_desc->init(gspca_dev);
1535 	if (ret < 0)
1536 		goto out;
1537 	if (sd_desc->init_controls)
1538 		ret = sd_desc->init_controls(gspca_dev);
1539 	if (ret < 0)
1540 		goto out;
1541 	gspca_set_default_mode(gspca_dev);
1542 
1543 	ret = gspca_input_connect(gspca_dev);
1544 	if (ret)
1545 		goto out;
1546 
1547 #ifdef CONFIG_VIDEO_ADV_DEBUG
1548 	if (!gspca_dev->sd_desc->get_register)
1549 		v4l2_disable_ioctl(&gspca_dev->vdev, VIDIOC_DBG_G_REGISTER);
1550 	if (!gspca_dev->sd_desc->set_register)
1551 		v4l2_disable_ioctl(&gspca_dev->vdev, VIDIOC_DBG_S_REGISTER);
1552 #endif
1553 	if (!gspca_dev->sd_desc->get_jcomp)
1554 		v4l2_disable_ioctl(&gspca_dev->vdev, VIDIOC_G_JPEGCOMP);
1555 	if (!gspca_dev->sd_desc->set_jcomp)
1556 		v4l2_disable_ioctl(&gspca_dev->vdev, VIDIOC_S_JPEGCOMP);
1557 
1558 	/* init video stuff */
1559 	ret = video_register_device(&gspca_dev->vdev,
1560 				  VFL_TYPE_VIDEO,
1561 				  -1);
1562 	if (ret < 0) {
1563 		pr_err("video_register_device err %d\n", ret);
1564 		goto out;
1565 	}
1566 
1567 	usb_set_intfdata(intf, gspca_dev);
1568 	gspca_dbg(gspca_dev, D_PROBE, "%s created\n",
1569 		  video_device_node_name(&gspca_dev->vdev));
1570 
1571 	gspca_input_create_urb(gspca_dev);
1572 
1573 	return 0;
1574 out:
1575 #if IS_ENABLED(CONFIG_INPUT)
1576 	if (gspca_dev->input_dev)
1577 		input_unregister_device(gspca_dev->input_dev);
1578 #endif
1579 	v4l2_ctrl_handler_free(gspca_dev->vdev.ctrl_handler);
1580 	v4l2_device_unregister(&gspca_dev->v4l2_dev);
1581 	if (sd_desc->probe_error)
1582 		sd_desc->probe_error(gspca_dev);
1583 	kfree(gspca_dev->usb_buf);
1584 	kfree(gspca_dev);
1585 	return ret;
1586 }
1587 EXPORT_SYMBOL(gspca_dev_probe2);
1588 
1589 /* same function as the previous one, but check the interface */
gspca_dev_probe(struct usb_interface * intf,const struct usb_device_id * id,const struct sd_desc * sd_desc,int dev_size,struct module * module)1590 int gspca_dev_probe(struct usb_interface *intf,
1591 		const struct usb_device_id *id,
1592 		const struct sd_desc *sd_desc,
1593 		int dev_size,
1594 		struct module *module)
1595 {
1596 	struct usb_device *dev = interface_to_usbdev(intf);
1597 
1598 	/* we don't handle multi-config cameras */
1599 	if (dev->descriptor.bNumConfigurations != 1) {
1600 		pr_err("%04x:%04x too many config\n",
1601 		       id->idVendor, id->idProduct);
1602 		return -ENODEV;
1603 	}
1604 
1605 	/* the USB video interface must be the first one */
1606 	if (dev->actconfig->desc.bNumInterfaces != 1
1607 	 && intf->cur_altsetting->desc.bInterfaceNumber != 0)
1608 		return -ENODEV;
1609 
1610 	return gspca_dev_probe2(intf, id, sd_desc, dev_size, module);
1611 }
1612 EXPORT_SYMBOL(gspca_dev_probe);
1613 
1614 /*
1615  * USB disconnection
1616  *
1617  * This function must be called by the sub-driver
1618  * when the device disconnects, after the specific resources are freed.
1619  */
gspca_disconnect(struct usb_interface * intf)1620 void gspca_disconnect(struct usb_interface *intf)
1621 {
1622 	struct gspca_dev *gspca_dev = usb_get_intfdata(intf);
1623 #if IS_ENABLED(CONFIG_INPUT)
1624 	struct input_dev *input_dev;
1625 #endif
1626 
1627 	gspca_dbg(gspca_dev, D_PROBE, "%s disconnect\n",
1628 		  video_device_node_name(&gspca_dev->vdev));
1629 
1630 	mutex_lock(&gspca_dev->usb_lock);
1631 	gspca_dev->present = false;
1632 	destroy_urbs(gspca_dev);
1633 	gspca_input_destroy_urb(gspca_dev);
1634 
1635 	vb2_queue_error(&gspca_dev->queue);
1636 
1637 #if IS_ENABLED(CONFIG_INPUT)
1638 	input_dev = gspca_dev->input_dev;
1639 	if (input_dev) {
1640 		gspca_dev->input_dev = NULL;
1641 		input_unregister_device(input_dev);
1642 	}
1643 #endif
1644 
1645 	v4l2_device_disconnect(&gspca_dev->v4l2_dev);
1646 	video_unregister_device(&gspca_dev->vdev);
1647 
1648 	mutex_unlock(&gspca_dev->usb_lock);
1649 
1650 	/* (this will call gspca_release() immediately or on last close) */
1651 	v4l2_device_put(&gspca_dev->v4l2_dev);
1652 }
1653 EXPORT_SYMBOL(gspca_disconnect);
1654 
1655 #ifdef CONFIG_PM
gspca_suspend(struct usb_interface * intf,pm_message_t message)1656 int gspca_suspend(struct usb_interface *intf, pm_message_t message)
1657 {
1658 	struct gspca_dev *gspca_dev = usb_get_intfdata(intf);
1659 
1660 	gspca_input_destroy_urb(gspca_dev);
1661 
1662 	if (!vb2_start_streaming_called(&gspca_dev->queue))
1663 		return 0;
1664 
1665 	mutex_lock(&gspca_dev->usb_lock);
1666 	gspca_dev->frozen = 1;		/* avoid urb error messages */
1667 	gspca_dev->usb_err = 0;
1668 	if (gspca_dev->sd_desc->stopN)
1669 		gspca_dev->sd_desc->stopN(gspca_dev);
1670 	destroy_urbs(gspca_dev);
1671 	gspca_set_alt0(gspca_dev);
1672 	if (gspca_dev->sd_desc->stop0)
1673 		gspca_dev->sd_desc->stop0(gspca_dev);
1674 	mutex_unlock(&gspca_dev->usb_lock);
1675 
1676 	return 0;
1677 }
1678 EXPORT_SYMBOL(gspca_suspend);
1679 
gspca_resume(struct usb_interface * intf)1680 int gspca_resume(struct usb_interface *intf)
1681 {
1682 	struct gspca_dev *gspca_dev = usb_get_intfdata(intf);
1683 	int streaming, ret = 0;
1684 
1685 	mutex_lock(&gspca_dev->usb_lock);
1686 	gspca_dev->frozen = 0;
1687 	gspca_dev->usb_err = 0;
1688 	gspca_dev->sd_desc->init(gspca_dev);
1689 	/*
1690 	 * Most subdrivers send all ctrl values on sd_start and thus
1691 	 * only write to the device registers on s_ctrl when streaming ->
1692 	 * Clear streaming to avoid setting all ctrls twice.
1693 	 */
1694 	streaming = vb2_start_streaming_called(&gspca_dev->queue);
1695 	if (streaming)
1696 		ret = gspca_init_transfer(gspca_dev);
1697 	else
1698 		gspca_input_create_urb(gspca_dev);
1699 	mutex_unlock(&gspca_dev->usb_lock);
1700 
1701 	return ret;
1702 }
1703 EXPORT_SYMBOL(gspca_resume);
1704 #endif
1705 
1706 /* -- module insert / remove -- */
gspca_init(void)1707 static int __init gspca_init(void)
1708 {
1709 	pr_info("v" GSPCA_VERSION " registered\n");
1710 	return 0;
1711 }
gspca_exit(void)1712 static void __exit gspca_exit(void)
1713 {
1714 }
1715 
1716 module_init(gspca_init);
1717 module_exit(gspca_exit);
1718 
1719 module_param_named(debug, gspca_debug, int, 0644);
1720 MODULE_PARM_DESC(debug,
1721 		"1:probe 2:config 3:stream 4:frame 5:packet 6:usbi 7:usbo");
1722