Merge branch 'drm-patches' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied...
[linux-2.6] / drivers / media / video / em28xx / em28xx-core.c
1 /*
2    em28xx-core.c - driver for Empia EM2800/EM2820/2840 USB video capture devices
3
4    Copyright (C) 2005 Ludovico Cavedon <cavedon@sssup.it>
5                       Markus Rechberger <mrechberger@gmail.com>
6                       Mauro Carvalho Chehab <mchehab@brturbo.com.br>
7                       Sascha Sommer <saschasommer@freenet.de>
8
9    This program is free software; you can redistribute it and/or modify
10    it under the terms of the GNU General Public License as published by
11    the Free Software Foundation; either version 2 of the License, or
12    (at your option) any later version.
13
14    This program is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17    GNU General Public License for more details.
18
19    You should have received a copy of the GNU General Public License
20    along with this program; if not, write to the Free Software
21    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  */
23
24 #include <linux/init.h>
25 #include <linux/list.h>
26 #include <linux/module.h>
27 #include <linux/moduleparam.h>
28 #include <linux/usb.h>
29 #include <linux/vmalloc.h>
30
31 #include "em28xx.h"
32
33 /* #define ENABLE_DEBUG_ISOC_FRAMES */
34
35 static unsigned int core_debug = 0;
36 module_param(core_debug,int,0644);
37 MODULE_PARM_DESC(core_debug,"enable debug messages [core]");
38
39 #define em28xx_coredbg(fmt, arg...) do {\
40         if (core_debug) \
41                 printk(KERN_INFO "%s %s :"fmt, \
42                          dev->name, __FUNCTION__ , ##arg); } while (0)
43
44 static unsigned int reg_debug = 0;
45 module_param(reg_debug,int,0644);
46 MODULE_PARM_DESC(reg_debug,"enable debug messages [URB reg]");
47
48 #define em28xx_regdbg(fmt, arg...) do {\
49         if (reg_debug) \
50                 printk(KERN_INFO "%s %s :"fmt, \
51                          dev->name, __FUNCTION__ , ##arg); } while (0)
52
53 static unsigned int isoc_debug = 0;
54 module_param(isoc_debug,int,0644);
55 MODULE_PARM_DESC(isoc_debug,"enable debug messages [isoc transfers]");
56
57 #define em28xx_isocdbg(fmt, arg...) do {\
58         if (isoc_debug) \
59                 printk(KERN_INFO "%s %s :"fmt, \
60                          dev->name, __FUNCTION__ , ##arg); } while (0)
61
62 static int alt = EM28XX_PINOUT;
63 module_param(alt, int, 0644);
64 MODULE_PARM_DESC(alt, "alternate setting to use for video endpoint");
65
66
67 /*
68  * em28xx_request_buffers()
69  * allocate a number of buffers
70  */
71 u32 em28xx_request_buffers(struct em28xx *dev, u32 count)
72 {
73         const size_t imagesize = PAGE_ALIGN(dev->frame_size);   /*needs to be page aligned cause the buffers can be mapped individually! */
74         void *buff = NULL;
75         u32 i;
76         em28xx_coredbg("requested %i buffers with size %zi", count, imagesize);
77         if (count > EM28XX_NUM_FRAMES)
78                 count = EM28XX_NUM_FRAMES;
79
80         dev->num_frames = count;
81         while (dev->num_frames > 0) {
82                 if ((buff = vmalloc_32(dev->num_frames * imagesize))) {
83                         memset(buff, 0, dev->num_frames * imagesize);
84                         break;
85                 }
86                 dev->num_frames--;
87         }
88
89         for (i = 0; i < dev->num_frames; i++) {
90                 dev->frame[i].bufmem = buff + i * imagesize;
91                 dev->frame[i].buf.index = i;
92                 dev->frame[i].buf.m.offset = i * imagesize;
93                 dev->frame[i].buf.length = dev->frame_size;
94                 dev->frame[i].buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
95                 dev->frame[i].buf.sequence = 0;
96                 dev->frame[i].buf.field = V4L2_FIELD_NONE;
97                 dev->frame[i].buf.memory = V4L2_MEMORY_MMAP;
98                 dev->frame[i].buf.flags = 0;
99         }
100         return dev->num_frames;
101 }
102
103 /*
104  * em28xx_queue_unusedframes()
105  * add all frames that are not currently in use to the inbuffer queue
106  */
107 void em28xx_queue_unusedframes(struct em28xx *dev)
108 {
109         unsigned long lock_flags;
110         u32 i;
111
112         for (i = 0; i < dev->num_frames; i++)
113                 if (dev->frame[i].state == F_UNUSED) {
114                         dev->frame[i].state = F_QUEUED;
115                         spin_lock_irqsave(&dev->queue_lock, lock_flags);
116                         list_add_tail(&dev->frame[i].frame, &dev->inqueue);
117                         spin_unlock_irqrestore(&dev->queue_lock, lock_flags);
118                 }
119 }
120
121 /*
122  * em28xx_release_buffers()
123  * free frame buffers
124  */
125 void em28xx_release_buffers(struct em28xx *dev)
126 {
127         if (dev->num_frames) {
128                 vfree(dev->frame[0].bufmem);
129                 dev->num_frames = 0;
130         }
131 }
132
133 /*
134  * em28xx_read_reg_req()
135  * reads data from the usb device specifying bRequest
136  */
137 int em28xx_read_reg_req_len(struct em28xx *dev, u8 req, u16 reg,
138                                    char *buf, int len)
139 {
140         int ret, byte;
141
142         if (dev->state & DEV_DISCONNECTED)
143                 return(-ENODEV);
144
145         em28xx_regdbg("req=%02x, reg=%02x ", req, reg);
146
147         ret = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0), req,
148                               USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
149                               0x0000, reg, buf, len, HZ);
150
151         if (reg_debug){
152                 printk(ret < 0 ? " failed!\n" : "%02x values: ", ret);
153                 for (byte = 0; byte < len; byte++) {
154                         printk(" %02x", buf[byte]);
155                 }
156                 printk("\n");
157         }
158
159         return ret;
160 }
161
162 /*
163  * em28xx_read_reg_req()
164  * reads data from the usb device specifying bRequest
165  */
166 int em28xx_read_reg_req(struct em28xx *dev, u8 req, u16 reg)
167 {
168         u8 val;
169         int ret;
170
171         if (dev->state & DEV_DISCONNECTED)
172                 return(-ENODEV);
173
174         em28xx_regdbg("req=%02x, reg=%02x:", req, reg);
175
176         ret = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0), req,
177                               USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
178                               0x0000, reg, &val, 1, HZ);
179
180         if (reg_debug)
181                 printk(ret < 0 ? " failed!\n" : "%02x\n", val);
182
183         if (ret < 0)
184                 return ret;
185
186         return val;
187 }
188
189 int em28xx_read_reg(struct em28xx *dev, u16 reg)
190 {
191         return em28xx_read_reg_req(dev, USB_REQ_GET_STATUS, reg);
192 }
193
194 /*
195  * em28xx_write_regs_req()
196  * sends data to the usb device, specifying bRequest
197  */
198 int em28xx_write_regs_req(struct em28xx *dev, u8 req, u16 reg, char *buf,
199                                  int len)
200 {
201         int ret;
202
203         /*usb_control_msg seems to expect a kmalloced buffer */
204         unsigned char *bufs;
205
206         if (dev->state & DEV_DISCONNECTED)
207                 return(-ENODEV);
208
209         bufs = kmalloc(len, GFP_KERNEL);
210
211         em28xx_regdbg("req=%02x reg=%02x:", req, reg);
212
213         if (reg_debug) {
214                 int i;
215                 for (i = 0; i < len; ++i)
216                         printk (" %02x", (unsigned char)buf[i]);
217                 printk ("\n");
218         }
219
220         if (!bufs)
221                 return -ENOMEM;
222         memcpy(bufs, buf, len);
223         ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0), req,
224                               USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
225                               0x0000, reg, bufs, len, HZ);
226         msleep(5);              /* FIXME: magic number */
227         kfree(bufs);
228         return ret;
229 }
230
231 int em28xx_write_regs(struct em28xx *dev, u16 reg, char *buf, int len)
232 {
233         return em28xx_write_regs_req(dev, USB_REQ_GET_STATUS, reg, buf, len);
234 }
235
236 /*
237  * em28xx_write_reg_bits()
238  * sets only some bits (specified by bitmask) of a register, by first reading
239  * the actual value
240  */
241 int em28xx_write_reg_bits(struct em28xx *dev, u16 reg, u8 val,
242                                  u8 bitmask)
243 {
244         int oldval;
245         u8 newval;
246         if ((oldval = em28xx_read_reg(dev, reg)) < 0)
247                 return oldval;
248         newval = (((u8) oldval) & ~bitmask) | (val & bitmask);
249         return em28xx_write_regs(dev, reg, &newval, 1);
250 }
251
252 /*
253  * em28xx_write_ac97()
254  * write a 16 bit value to the specified AC97 address (LSB first!)
255  */
256 int em28xx_write_ac97(struct em28xx *dev, u8 reg, u8 * val)
257 {
258         int ret;
259         u8 addr = reg & 0x7f;
260         if ((ret = em28xx_write_regs(dev, AC97LSB_REG, val, 2)) < 0)
261                 return ret;
262         if ((ret = em28xx_write_regs(dev, AC97ADDR_REG, &addr, 1)) < 0)
263                 return ret;
264         if ((ret = em28xx_read_reg(dev, AC97BUSY_REG)) < 0)
265                 return ret;
266         else if (((u8) ret) & 0x01) {
267                 em28xx_warn ("AC97 command still being executed: not handled properly!\n");
268         }
269         return 0;
270 }
271
272 int em28xx_audio_analog_set(struct em28xx *dev)
273 {
274         char s[2] = { 0x00, 0x00 };
275         s[0] |= 0x1f - dev->volume;
276         s[1] |= 0x1f - dev->volume;
277         if (dev->mute)
278                 s[1] |= 0x80;
279         return em28xx_write_ac97(dev, MASTER_AC97, s);
280 }
281
282
283 int em28xx_colorlevels_set_default(struct em28xx *dev)
284 {
285         em28xx_write_regs(dev, YGAIN_REG, "\x10", 1);   /* contrast */
286         em28xx_write_regs(dev, YOFFSET_REG, "\x00", 1); /* brightness */
287         em28xx_write_regs(dev, UVGAIN_REG, "\x10", 1);  /* saturation */
288         em28xx_write_regs(dev, UOFFSET_REG, "\x00", 1);
289         em28xx_write_regs(dev, VOFFSET_REG, "\x00", 1);
290         em28xx_write_regs(dev, SHARPNESS_REG, "\x00", 1);
291
292         em28xx_write_regs(dev, GAMMA_REG, "\x20", 1);
293         em28xx_write_regs(dev, RGAIN_REG, "\x20", 1);
294         em28xx_write_regs(dev, GGAIN_REG, "\x20", 1);
295         em28xx_write_regs(dev, BGAIN_REG, "\x20", 1);
296         em28xx_write_regs(dev, ROFFSET_REG, "\x00", 1);
297         em28xx_write_regs(dev, GOFFSET_REG, "\x00", 1);
298         return em28xx_write_regs(dev, BOFFSET_REG, "\x00", 1);
299 }
300
301 int em28xx_capture_start(struct em28xx *dev, int start)
302 {
303         int ret;
304         /* FIXME: which is the best order? */
305         /* video registers are sampled by VREF */
306         if ((ret = em28xx_write_reg_bits(dev, USBSUSP_REG, start ? 0x10 : 0x00,
307                                           0x10)) < 0)
308                 return ret;
309         /* enable video capture */
310         return em28xx_write_regs(dev, VINENABLE_REG, start ? "\x67" : "\x27", 1);
311 }
312
313 int em28xx_outfmt_set_yuv422(struct em28xx *dev)
314 {
315         em28xx_write_regs(dev, OUTFMT_REG, "\x34", 1);
316         em28xx_write_regs(dev, VINMODE_REG, "\x10", 1);
317         return em28xx_write_regs(dev, VINCTRL_REG, "\x11", 1);
318 }
319
320 int em28xx_accumulator_set(struct em28xx *dev, u8 xmin, u8 xmax, u8 ymin,
321                                   u8 ymax)
322 {
323         em28xx_coredbg("em28xx Scale: (%d,%d)-(%d,%d)\n", xmin, ymin, xmax, ymax);
324
325         em28xx_write_regs(dev, XMIN_REG, &xmin, 1);
326         em28xx_write_regs(dev, XMAX_REG, &xmax, 1);
327         em28xx_write_regs(dev, YMIN_REG, &ymin, 1);
328         return em28xx_write_regs(dev, YMAX_REG, &ymax, 1);
329 }
330
331 int em28xx_capture_area_set(struct em28xx *dev, u8 hstart, u8 vstart,
332                                    u16 width, u16 height)
333 {
334         u8 cwidth = width;
335         u8 cheight = height;
336         u8 overflow = (height >> 7 & 0x02) | (width >> 8 & 0x01);
337
338         em28xx_coredbg("em28xx Area Set: (%d,%d)\n", (width | (overflow & 2) << 7),
339                         (height | (overflow & 1) << 8));
340
341         em28xx_write_regs(dev, HSTART_REG, &hstart, 1);
342         em28xx_write_regs(dev, VSTART_REG, &vstart, 1);
343         em28xx_write_regs(dev, CWIDTH_REG, &cwidth, 1);
344         em28xx_write_regs(dev, CHEIGHT_REG, &cheight, 1);
345         return em28xx_write_regs(dev, OFLOW_REG, &overflow, 1);
346 }
347
348 int em28xx_scaler_set(struct em28xx *dev, u16 h, u16 v)
349 {
350         u8 mode;
351         /* the em2800 scaler only supports scaling down to 50% */
352         if(dev->is_em2800)
353                 mode = (v ? 0x20 : 0x00) | (h ? 0x10 : 0x00);
354         else {
355                 u8 buf[2];
356                 buf[0] = h;
357                 buf[1] = h >> 8;
358                 em28xx_write_regs(dev, HSCALELOW_REG, (char *)buf, 2);
359                 buf[0] = v;
360                 buf[1] = v >> 8;
361                 em28xx_write_regs(dev, VSCALELOW_REG, (char *)buf, 2);
362                 /* it seems that both H and V scalers must be active to work correctly */
363                 mode = (h || v)? 0x30: 0x00;
364         }
365         return em28xx_write_reg_bits(dev, COMPR_REG, mode, 0x30);
366 }
367
368 /* FIXME: this only function read values from dev */
369 int em28xx_resolution_set(struct em28xx *dev)
370 {
371         int width, height;
372         width = norm_maxw(dev);
373         height = norm_maxh(dev) >> 1;
374
375         em28xx_outfmt_set_yuv422(dev);
376         em28xx_accumulator_set(dev, 1, (width - 4) >> 2, 1, (height - 4) >> 2);
377         em28xx_capture_area_set(dev, 0, 0, width >> 2, height >> 2);
378         return em28xx_scaler_set(dev, dev->hscale, dev->vscale);
379 }
380
381
382 /******************* isoc transfer handling ****************************/
383
384 #ifdef ENABLE_DEBUG_ISOC_FRAMES
385 static void em28xx_isoc_dump(struct urb *urb, struct pt_regs *regs)
386 {
387         int len = 0;
388         int ntrans = 0;
389         int i;
390
391         printk(KERN_DEBUG "isocIrq: sf=%d np=%d ec=%x\n",
392                urb->start_frame, urb->number_of_packets,
393                urb->error_count);
394         for (i = 0; i < urb->number_of_packets; i++) {
395                 unsigned char *buf =
396                                 urb->transfer_buffer +
397                                 urb->iso_frame_desc[i].offset;
398                 int alen = urb->iso_frame_desc[i].actual_length;
399                 if (alen > 0) {
400                         if (buf[0] == 0x88) {
401                                 ntrans++;
402                                 len += alen;
403                         } else if (buf[0] == 0x22) {
404                                 printk(KERN_DEBUG
405                                                 "= l=%d nt=%d bpp=%d\n",
406                                 len - 4 * ntrans, ntrans,
407                                 ntrans == 0 ? 0 : len / ntrans);
408                                 ntrans = 1;
409                                 len = alen;
410                         } else
411                                 printk(KERN_DEBUG "!\n");
412                 }
413                 printk(KERN_DEBUG "   n=%d s=%d al=%d %x\n", i,
414                        urb->iso_frame_desc[i].status,
415                        urb->iso_frame_desc[i].actual_length,
416                        (unsigned int)
417                                        *((unsigned char *)(urb->transfer_buffer +
418                                        urb->iso_frame_desc[i].
419                                        offset)));
420         }
421 }
422 #endif
423
424 static inline int em28xx_isoc_video(struct em28xx *dev,struct em28xx_frame_t **f,
425                                     unsigned long *lock_flags, unsigned char buf)
426 {
427         if (!(buf & 0x01)) {
428                 if ((*f)->state == F_GRABBING) {
429                         /*previous frame is incomplete */
430                         if ((*f)->fieldbytesused < dev->field_size) {
431                                 (*f)->state = F_ERROR;
432                                 em28xx_isocdbg ("dropping incomplete bottom field (%i missing bytes)",
433                                          dev->field_size-(*f)->fieldbytesused);
434                         } else {
435                                 (*f)->state = F_DONE;
436                                 (*f)->buf.bytesused = dev->frame_size;
437                         }
438                 }
439                 if ((*f)->state == F_DONE || (*f)->state == F_ERROR) {
440                         /* move current frame to outqueue and get next free buffer from inqueue */
441                         spin_lock_irqsave(&dev-> queue_lock, *lock_flags);
442                         list_move_tail(&(*f)->frame, &dev->outqueue);
443                         if (!list_empty(&dev->inqueue))
444                                 (*f) = list_entry(dev-> inqueue.next,
445                         struct em28xx_frame_t,frame);
446                         else
447                                 (*f) = NULL;
448                         spin_unlock_irqrestore(&dev->queue_lock,*lock_flags);
449                 }
450                 if (!(*f)) {
451                         em28xx_isocdbg ("new frame but no buffer is free");
452                         return -1;
453                 }
454                 do_gettimeofday(&(*f)->buf.timestamp);
455                 (*f)->buf.sequence = ++dev->frame_count;
456                 (*f)->buf.field = V4L2_FIELD_INTERLACED;
457                 (*f)->state = F_GRABBING;
458                 (*f)->buf.bytesused = 0;
459                 (*f)->top_field = 1;
460                 (*f)->fieldbytesused = 0;
461         } else {
462                                         /* acquiring bottom field */
463                 if ((*f)->state == F_GRABBING) {
464                         if (!(*f)->top_field) {
465                                 (*f)->state = F_ERROR;
466                                 em28xx_isocdbg ("unexpected begin of bottom field; discarding it");
467                         } else if ((*f)-> fieldbytesused < dev->field_size - 172) {
468                                 (*f)->state = F_ERROR;
469                                 em28xx_isocdbg ("dropping incomplete top field (%i missing bytes)",
470                                          dev->field_size-(*f)->fieldbytesused);
471                         } else {
472                                 (*f)->top_field = 0;
473                                 (*f)->fieldbytesused = 0;
474                         }
475                 }
476         }
477         return (0);
478 }
479
480 static inline void em28xx_isoc_video_copy(struct em28xx *dev,
481                                           struct em28xx_frame_t **f, unsigned char *buf, int len)
482 {
483         void *fieldstart, *startwrite, *startread;
484         int linesdone, currlinedone, offset, lencopy,remain;
485
486         if(dev->frame_size != (*f)->buf.length){
487                 em28xx_err("frame_size %i and buf.length %i are different!!!\n",dev->frame_size,(*f)->buf.length);
488                 return;
489         }
490
491         if ((*f)->fieldbytesused + len > dev->field_size)
492                 len =dev->field_size - (*f)->fieldbytesused;
493
494         if (buf[0] != 0x88 && buf[0] != 0x22) {
495                 em28xx_isocdbg("frame is not complete\n");
496                 startread = buf;
497                 len+=4;
498         } else
499                 startread = buf + 4;
500
501         remain = len;
502
503         if ((*f)->top_field)
504                 fieldstart = (*f)->bufmem;
505         else
506                 fieldstart = (*f)->bufmem + dev->bytesperline;
507
508         linesdone = (*f)->fieldbytesused / dev->bytesperline;
509         currlinedone = (*f)->fieldbytesused % dev->bytesperline;
510         offset = linesdone * dev->bytesperline * 2 + currlinedone;
511         startwrite = fieldstart + offset;
512         lencopy = dev->bytesperline - currlinedone;
513         lencopy = lencopy > remain ? remain : lencopy;
514
515         memcpy(startwrite, startread, lencopy);
516         remain -= lencopy;
517
518         while (remain > 0) {
519                 startwrite += lencopy + dev->bytesperline;
520                 startread += lencopy;
521                 if (dev->bytesperline > remain)
522                         lencopy = remain;
523                 else
524                         lencopy = dev->bytesperline;
525
526                 memcpy(startwrite, startread, lencopy);
527                 remain -= lencopy;
528         }
529
530         (*f)->fieldbytesused += len;
531 }
532
533 /*
534  * em28xx_isoIrq()
535  * handles the incoming isoc urbs and fills the frames from our inqueue
536  */
537 void em28xx_isocIrq(struct urb *urb, struct pt_regs *regs)
538 {
539         struct em28xx *dev = urb->context;
540         int i, status;
541         struct em28xx_frame_t **f;
542         unsigned long lock_flags;
543
544         if (!dev)
545                 return;
546 #ifdef ENABLE_DEBUG_ISOC_FRAMES
547         if (isoc_debug>1)
548                 em28xx_isoc_dump(urb, regs);
549 #endif
550
551         if (urb->status == -ENOENT)
552                 return;
553
554         f = &dev->frame_current;
555
556         if (dev->stream == STREAM_INTERRUPT) {
557                 dev->stream = STREAM_OFF;
558                 if ((*f))
559                         (*f)->state = F_QUEUED;
560                 em28xx_isocdbg("stream interrupted");
561                 wake_up_interruptible(&dev->wait_stream);
562         }
563
564         if ((dev->state & DEV_DISCONNECTED) || (dev->state & DEV_MISCONFIGURED))
565                 return;
566
567         if (dev->stream == STREAM_ON && !list_empty(&dev->inqueue)) {
568                 if (!(*f))
569                         (*f) = list_entry(dev->inqueue.next,
570                 struct em28xx_frame_t, frame);
571
572                 for (i = 0; i < urb->number_of_packets; i++) {
573                         unsigned char *buf = urb->transfer_buffer +
574                                         urb->iso_frame_desc[i].offset;
575                         int len = urb->iso_frame_desc[i].actual_length - 4;
576
577                         if (urb->iso_frame_desc[i].status) {
578                                 em28xx_isocdbg("data error: [%d] len=%d, status=%d", i,
579                                         urb->iso_frame_desc[i].actual_length,
580                                         urb->iso_frame_desc[i].status);
581                                 if (urb->iso_frame_desc[i].status != -EPROTO)
582                                         continue;
583                         }
584                         if (urb->iso_frame_desc[i].actual_length <= 0) {
585                                 em28xx_isocdbg("packet %d is empty",i);
586                                 continue;
587                         }
588                         if (urb->iso_frame_desc[i].actual_length >
589                                                  dev->max_pkt_size) {
590                                 em28xx_isocdbg("packet bigger than packet size");
591                                 continue;
592                         }
593                         /*new frame */
594                         if (buf[0] == 0x22 && buf[1] == 0x5a) {
595                                 em28xx_isocdbg("Video frame, length=%i!",len);
596
597                                 if (em28xx_isoc_video(dev,f,&lock_flags,buf[2]))
598                                 break;
599                         } else if (buf[0]==0x33 && buf[1]==0x95 && buf[2]==0x00) {
600                                 em28xx_isocdbg("VBI HEADER!!!");
601                         }
602
603                         /* actual copying */
604                         if ((*f)->state == F_GRABBING) {
605                                 em28xx_isoc_video_copy(dev,f,buf, len);
606                         }
607                 }
608         }
609
610         for (i = 0; i < urb->number_of_packets; i++) {
611                 urb->iso_frame_desc[i].status = 0;
612                 urb->iso_frame_desc[i].actual_length = 0;
613         }
614
615         urb->status = 0;
616         if ((status = usb_submit_urb(urb, GFP_ATOMIC))) {
617                 em28xx_errdev("resubmit of urb failed (error=%i)\n", status);
618                 dev->state |= DEV_MISCONFIGURED;
619         }
620         wake_up_interruptible(&dev->wait_frame);
621         return;
622 }
623
624 /*
625  * em28xx_uninit_isoc()
626  * deallocates the buffers and urbs allocated during em28xx_init_iosc()
627  */
628 void em28xx_uninit_isoc(struct em28xx *dev)
629 {
630         int i;
631
632         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
633                 if (dev->urb[i]) {
634                         usb_kill_urb(dev->urb[i]);
635                         if (dev->transfer_buffer[i]){
636                                 usb_buffer_free(dev->udev,(EM28XX_NUM_PACKETS*dev->max_pkt_size),dev->transfer_buffer[i],dev->urb[i]->transfer_dma);
637                         }
638                         usb_free_urb(dev->urb[i]);
639                 }
640                 dev->urb[i] = NULL;
641                 dev->transfer_buffer[i] = NULL;
642         }
643         em28xx_capture_start(dev, 0);
644 }
645
646 /*
647  * em28xx_init_isoc()
648  * allocates transfer buffers and submits the urbs for isoc transfer
649  */
650 int em28xx_init_isoc(struct em28xx *dev)
651 {
652         /* change interface to 3 which allowes the biggest packet sizes */
653         int i, errCode;
654         const int sb_size = EM28XX_NUM_PACKETS * dev->max_pkt_size;
655
656         /* reset streaming vars */
657         dev->frame_current = NULL;
658         dev->frame_count = 0;
659
660         /* allocate urbs */
661         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
662                 struct urb *urb;
663                 int j, k;
664                 /* allocate transfer buffer */
665                 urb = usb_alloc_urb(EM28XX_NUM_PACKETS, GFP_KERNEL);
666                 if (!urb){
667                         em28xx_errdev("cannot alloc urb %i\n", i);
668                         em28xx_uninit_isoc(dev);
669                         return -ENOMEM;
670                 }
671                 dev->transfer_buffer[i] = usb_buffer_alloc(dev->udev, sb_size, GFP_KERNEL,&urb->transfer_dma);
672                 if (!dev->transfer_buffer[i]) {
673                         em28xx_errdev
674                                         ("unable to allocate %i bytes for transfer buffer %i\n",
675                                          sb_size, i);
676                         em28xx_uninit_isoc(dev);
677                         return -ENOMEM;
678                 }
679                 memset(dev->transfer_buffer[i], 0, sb_size);
680                 urb->dev = dev->udev;
681                 urb->context = dev;
682                 urb->pipe = usb_rcvisocpipe(dev->udev, 0x82);
683                 urb->transfer_flags = URB_ISO_ASAP;
684                 urb->interval = 1;
685                 urb->transfer_buffer = dev->transfer_buffer[i];
686                 urb->complete = em28xx_isocIrq;
687                 urb->number_of_packets = EM28XX_NUM_PACKETS;
688                 urb->transfer_buffer_length = sb_size;
689                 for (j = k = 0; j < EM28XX_NUM_PACKETS;
690                                 j++, k += dev->max_pkt_size) {
691                         urb->iso_frame_desc[j].offset = k;
692                         urb->iso_frame_desc[j].length =
693                                 dev->max_pkt_size;
694                 }
695                 dev->urb[i] = urb;
696         }
697
698         /* submit urbs */
699         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
700                 errCode = usb_submit_urb(dev->urb[i], GFP_KERNEL);
701                 if (errCode) {
702                         em28xx_errdev("submit of urb %i failed (error=%i)\n", i,
703                                       errCode);
704                         em28xx_uninit_isoc(dev);
705                         return errCode;
706                 }
707         }
708
709         return 0;
710 }
711
712 int em28xx_set_alternate(struct em28xx *dev)
713 {
714         int errCode, prev_alt = dev->alt;
715         dev->alt = alt;
716         if (dev->alt == 0) {
717                 int i;
718                 for(i=0;i< dev->num_alt; i++)
719                         if(dev->alt_max_pkt_size[i]>dev->alt_max_pkt_size[dev->alt])
720                                 dev->alt=i;
721         }
722
723         if (dev->alt != prev_alt) {
724                 dev->max_pkt_size = dev->alt_max_pkt_size[dev->alt];
725                 em28xx_coredbg("setting alternate %d with wMaxPacketSize=%u\n", dev->alt,
726                        dev->max_pkt_size);
727                 errCode = usb_set_interface(dev->udev, 0, dev->alt);
728                 if (errCode < 0) {
729                         em28xx_errdev ("cannot change alternate number to %d (error=%i)\n",
730                                                         dev->alt, errCode);
731                         return errCode;
732                 }
733         }
734         return 0;
735 }