V4L/DVB (7179): Allow more than one em28xx board
[linux-2.6.git] / 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@infradead.org>
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/usb.h>
28 #include <linux/vmalloc.h>
29
30 #include "em28xx.h"
31
32 /* #define ENABLE_DEBUG_ISOC_FRAMES */
33
34 static unsigned int core_debug = 0;
35 module_param(core_debug,int,0644);
36 MODULE_PARM_DESC(core_debug,"enable debug messages [core]");
37
38 #define em28xx_coredbg(fmt, arg...) do {\
39         if (core_debug) \
40                 printk(KERN_INFO "%s %s :"fmt, \
41                          dev->name, __FUNCTION__ , ##arg); } while (0)
42
43 static unsigned int reg_debug = 0;
44 module_param(reg_debug,int,0644);
45 MODULE_PARM_DESC(reg_debug,"enable debug messages [URB reg]");
46
47 #define em28xx_regdbg(fmt, arg...) do {\
48         if (reg_debug) \
49                 printk(KERN_INFO "%s %s :"fmt, \
50                          dev->name, __FUNCTION__ , ##arg); } while (0)
51
52 static unsigned int isoc_debug = 0;
53 module_param(isoc_debug,int,0644);
54 MODULE_PARM_DESC(isoc_debug,"enable debug messages [isoc transfers]");
55
56 #define em28xx_isocdbg(fmt, arg...) do {\
57         if (isoc_debug) \
58                 printk(KERN_INFO "%s %s :"fmt, \
59                          dev->name, __FUNCTION__ , ##arg); } while (0)
60
61 static int alt = EM28XX_PINOUT;
62 module_param(alt, int, 0644);
63 MODULE_PARM_DESC(alt, "alternate setting to use for video endpoint");
64
65
66 /*
67  * em28xx_request_buffers()
68  * allocate a number of buffers
69  */
70 u32 em28xx_request_buffers(struct em28xx *dev, u32 count)
71 {
72         const size_t imagesize = PAGE_ALIGN(dev->frame_size);   /*needs to be page aligned cause the buffers can be mapped individually! */
73         void *buff = NULL;
74         u32 i;
75         em28xx_coredbg("requested %i buffers with size %zi\n",
76                         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", (unsigned char)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" :
182                                  "%02x\n", (unsigned char) val);
183
184         if (ret < 0)
185                 return ret;
186
187         return val;
188 }
189
190 int em28xx_read_reg(struct em28xx *dev, u16 reg)
191 {
192         return em28xx_read_reg_req(dev, USB_REQ_GET_STATUS, reg);
193 }
194
195 /*
196  * em28xx_write_regs_req()
197  * sends data to the usb device, specifying bRequest
198  */
199 int em28xx_write_regs_req(struct em28xx *dev, u8 req, u16 reg, char *buf,
200                                  int len)
201 {
202         int ret;
203
204         /*usb_control_msg seems to expect a kmalloced buffer */
205         unsigned char *bufs;
206
207         if (dev->state & DEV_DISCONNECTED)
208                 return(-ENODEV);
209
210         bufs = kmalloc(len, GFP_KERNEL);
211
212         em28xx_regdbg("req=%02x reg=%02x:", req, reg);
213
214         if (reg_debug) {
215                 int i;
216                 for (i = 0; i < len; ++i)
217                         printk (" %02x", (unsigned char)buf[i]);
218                 printk ("\n");
219         }
220
221         if (!bufs)
222                 return -ENOMEM;
223         memcpy(bufs, buf, len);
224         ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0), req,
225                               USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
226                               0x0000, reg, bufs, len, HZ);
227         msleep(5);              /* FIXME: magic number */
228         kfree(bufs);
229         return ret;
230 }
231
232 int em28xx_write_regs(struct em28xx *dev, u16 reg, char *buf, int len)
233 {
234         return em28xx_write_regs_req(dev, USB_REQ_GET_STATUS, reg, buf, len);
235 }
236
237 /*
238  * em28xx_write_reg_bits()
239  * sets only some bits (specified by bitmask) of a register, by first reading
240  * the actual value
241  */
242 static int em28xx_write_reg_bits(struct em28xx *dev, u16 reg, u8 val,
243                                  u8 bitmask)
244 {
245         int oldval;
246         u8 newval;
247         if ((oldval = em28xx_read_reg(dev, reg)) < 0)
248                 return oldval;
249         newval = (((u8) oldval) & ~bitmask) | (val & bitmask);
250         return em28xx_write_regs(dev, reg, &newval, 1);
251 }
252
253 /*
254  * em28xx_write_ac97()
255  * write a 16 bit value to the specified AC97 address (LSB first!)
256  */
257 static int em28xx_write_ac97(struct em28xx *dev, u8 reg, u8 *val)
258 {
259         int ret, i;
260         u8 addr = reg & 0x7f;
261         if ((ret = em28xx_write_regs(dev, AC97LSB_REG, val, 2)) < 0)
262                 return ret;
263         if ((ret = em28xx_write_regs(dev, AC97ADDR_REG, &addr, 1)) < 0)
264                 return ret;
265
266         /* Wait up to 50 ms for AC97 command to complete */
267         for (i = 0; i < 10; i++) {
268                 if ((ret = em28xx_read_reg(dev, AC97BUSY_REG)) < 0)
269                         return ret;
270                 if (!((u8) ret) & 0x01)
271                         return 0;
272                 msleep(5);
273         }
274         em28xx_warn ("AC97 command still being executed: not handled properly!\n");
275         return 0;
276 }
277
278 static int em28xx_set_audio_source(struct em28xx *dev)
279 {
280         static char *enable  = "\x08\x08";
281         static char *disable = "\x08\x88";
282         char *video = enable, *line = disable;
283         int ret;
284         u8 input;
285
286         if (dev->is_em2800) {
287                 if (dev->ctl_ainput)
288                         input = EM2800_AUDIO_SRC_LINE;
289                 else
290                         input = EM2800_AUDIO_SRC_TUNER;
291
292                 ret = em28xx_write_regs(dev, EM2800_AUDIOSRC_REG, &input, 1);
293                 if (ret < 0)
294                         return ret;
295         }
296
297         if (dev->has_msp34xx)
298                 input = EM28XX_AUDIO_SRC_TUNER;
299         else {
300                 switch (dev->ctl_ainput) {
301                 case EM28XX_AMUX_VIDEO:
302                         input = EM28XX_AUDIO_SRC_TUNER;
303                         break;
304                 case EM28XX_AMUX_LINE_IN:
305                         input = EM28XX_AUDIO_SRC_LINE;
306                         break;
307                 case EM28XX_AMUX_AC97_VIDEO:
308                         input = EM28XX_AUDIO_SRC_LINE;
309                         break;
310                 case EM28XX_AMUX_AC97_LINE_IN:
311                         input = EM28XX_AUDIO_SRC_LINE;
312                         video = disable;
313                         line  = enable;
314                         break;
315                 }
316         }
317
318         ret = em28xx_write_reg_bits(dev, AUDIOSRC_REG, input, 0xc0);
319         if (ret < 0)
320                 return ret;
321         msleep(5);
322
323         /* Sets AC97 mixer registers
324            This is seems to be needed, even for non-ac97 configs
325          */
326         ret = em28xx_write_ac97(dev, VIDEO_AC97, video);
327         if (ret < 0)
328                 return ret;
329
330         ret = em28xx_write_ac97(dev, LINE_IN_AC97, line);
331
332         return ret;
333 }
334
335 int em28xx_audio_analog_set(struct em28xx *dev)
336 {
337         int ret;
338         char s[2] = { 0x00, 0x00 };
339         u8 xclk = 0x07;
340
341         s[0] |= 0x1f - dev->volume;
342         s[1] |= 0x1f - dev->volume;
343
344         /* Mute */
345         s[1] |= 0x80;
346         ret = em28xx_write_ac97(dev, MASTER_AC97, s);
347
348         if (ret < 0)
349                 return ret;
350
351         if (dev->has_12mhz_i2s)
352                 xclk |= 0x20;
353
354         if (!dev->mute)
355                 xclk |= 0x80;
356
357         ret = em28xx_write_reg_bits(dev, XCLK_REG, xclk, 0xa7);
358         if (ret < 0)
359                 return ret;
360         msleep(10);
361
362         /* Selects the proper audio input */
363         ret = em28xx_set_audio_source(dev);
364
365         /* Unmute device */
366         if (!dev->mute)
367                 s[1] &= ~0x80;
368         ret = em28xx_write_ac97(dev, MASTER_AC97, s);
369
370         return ret;
371 }
372 EXPORT_SYMBOL_GPL(em28xx_audio_analog_set);
373
374 int em28xx_colorlevels_set_default(struct em28xx *dev)
375 {
376         em28xx_write_regs(dev, YGAIN_REG, "\x10", 1);   /* contrast */
377         em28xx_write_regs(dev, YOFFSET_REG, "\x00", 1); /* brightness */
378         em28xx_write_regs(dev, UVGAIN_REG, "\x10", 1);  /* saturation */
379         em28xx_write_regs(dev, UOFFSET_REG, "\x00", 1);
380         em28xx_write_regs(dev, VOFFSET_REG, "\x00", 1);
381         em28xx_write_regs(dev, SHARPNESS_REG, "\x00", 1);
382
383         em28xx_write_regs(dev, GAMMA_REG, "\x20", 1);
384         em28xx_write_regs(dev, RGAIN_REG, "\x20", 1);
385         em28xx_write_regs(dev, GGAIN_REG, "\x20", 1);
386         em28xx_write_regs(dev, BGAIN_REG, "\x20", 1);
387         em28xx_write_regs(dev, ROFFSET_REG, "\x00", 1);
388         em28xx_write_regs(dev, GOFFSET_REG, "\x00", 1);
389         return em28xx_write_regs(dev, BOFFSET_REG, "\x00", 1);
390 }
391
392 int em28xx_capture_start(struct em28xx *dev, int start)
393 {
394         int ret;
395         /* FIXME: which is the best order? */
396         /* video registers are sampled by VREF */
397         if ((ret = em28xx_write_reg_bits(dev, USBSUSP_REG, start ? 0x10 : 0x00,
398                                           0x10)) < 0)
399                 return ret;
400         /* enable video capture */
401         return em28xx_write_regs(dev, VINENABLE_REG, start ? "\x67" : "\x27", 1);
402 }
403
404 int em28xx_outfmt_set_yuv422(struct em28xx *dev)
405 {
406         em28xx_write_regs(dev, OUTFMT_REG, "\x34", 1);
407         em28xx_write_regs(dev, VINMODE_REG, "\x10", 1);
408         return em28xx_write_regs(dev, VINCTRL_REG, "\x11", 1);
409 }
410
411 static int em28xx_accumulator_set(struct em28xx *dev, u8 xmin, u8 xmax,
412                                   u8 ymin, u8 ymax)
413 {
414         em28xx_coredbg("em28xx Scale: (%d,%d)-(%d,%d)\n", xmin, ymin, xmax, ymax);
415
416         em28xx_write_regs(dev, XMIN_REG, &xmin, 1);
417         em28xx_write_regs(dev, XMAX_REG, &xmax, 1);
418         em28xx_write_regs(dev, YMIN_REG, &ymin, 1);
419         return em28xx_write_regs(dev, YMAX_REG, &ymax, 1);
420 }
421
422 static int em28xx_capture_area_set(struct em28xx *dev, u8 hstart, u8 vstart,
423                                    u16 width, u16 height)
424 {
425         u8 cwidth = width;
426         u8 cheight = height;
427         u8 overflow = (height >> 7 & 0x02) | (width >> 8 & 0x01);
428
429         em28xx_coredbg("em28xx Area Set: (%d,%d)\n", (width | (overflow & 2) << 7),
430                         (height | (overflow & 1) << 8));
431
432         em28xx_write_regs(dev, HSTART_REG, &hstart, 1);
433         em28xx_write_regs(dev, VSTART_REG, &vstart, 1);
434         em28xx_write_regs(dev, CWIDTH_REG, &cwidth, 1);
435         em28xx_write_regs(dev, CHEIGHT_REG, &cheight, 1);
436         return em28xx_write_regs(dev, OFLOW_REG, &overflow, 1);
437 }
438
439 static int em28xx_scaler_set(struct em28xx *dev, u16 h, u16 v)
440 {
441         u8 mode;
442         /* the em2800 scaler only supports scaling down to 50% */
443         if(dev->is_em2800)
444                 mode = (v ? 0x20 : 0x00) | (h ? 0x10 : 0x00);
445         else {
446                 u8 buf[2];
447                 buf[0] = h;
448                 buf[1] = h >> 8;
449                 em28xx_write_regs(dev, HSCALELOW_REG, (char *)buf, 2);
450                 buf[0] = v;
451                 buf[1] = v >> 8;
452                 em28xx_write_regs(dev, VSCALELOW_REG, (char *)buf, 2);
453                 /* it seems that both H and V scalers must be active to work correctly */
454                 mode = (h || v)? 0x30: 0x00;
455         }
456         return em28xx_write_reg_bits(dev, COMPR_REG, mode, 0x30);
457 }
458
459 /* FIXME: this only function read values from dev */
460 int em28xx_resolution_set(struct em28xx *dev)
461 {
462         int width, height;
463         width = norm_maxw(dev);
464         height = norm_maxh(dev) >> 1;
465
466         em28xx_outfmt_set_yuv422(dev);
467         em28xx_accumulator_set(dev, 1, (width - 4) >> 2, 1, (height - 4) >> 2);
468         em28xx_capture_area_set(dev, 0, 0, width >> 2, height >> 2);
469         return em28xx_scaler_set(dev, dev->hscale, dev->vscale);
470 }
471
472
473 /******************* isoc transfer handling ****************************/
474
475 #ifdef ENABLE_DEBUG_ISOC_FRAMES
476 static void em28xx_isoc_dump(struct urb *urb)
477 {
478         int len = 0;
479         int ntrans = 0;
480         int i;
481
482         printk(KERN_DEBUG "isocIrq: sf=%d np=%d ec=%x\n",
483                urb->start_frame, urb->number_of_packets,
484                urb->error_count);
485         for (i = 0; i < urb->number_of_packets; i++) {
486                 unsigned char *buf =
487                                 urb->transfer_buffer +
488                                 urb->iso_frame_desc[i].offset;
489                 int alen = urb->iso_frame_desc[i].actual_length;
490                 if (alen > 0) {
491                         if (buf[0] == 0x88) {
492                                 ntrans++;
493                                 len += alen;
494                         } else if (buf[0] == 0x22) {
495                                 printk(KERN_DEBUG
496                                                 "= l=%d nt=%d bpp=%d\n",
497                                 len - 4 * ntrans, ntrans,
498                                 ntrans == 0 ? 0 : len / ntrans);
499                                 ntrans = 1;
500                                 len = alen;
501                         } else
502                                 printk(KERN_DEBUG "!\n");
503                 }
504                 printk(KERN_DEBUG "   n=%d s=%d al=%d %x\n", i,
505                        urb->iso_frame_desc[i].status,
506                        urb->iso_frame_desc[i].actual_length,
507                        (unsigned int)
508                                        *((unsigned char *)(urb->transfer_buffer +
509                                        urb->iso_frame_desc[i].
510                                        offset)));
511         }
512 }
513 #endif
514
515 static inline int em28xx_isoc_video(struct em28xx *dev,struct em28xx_frame_t **f,
516                                     unsigned long *lock_flags, unsigned char buf)
517 {
518         if (!(buf & 0x01)) {
519                 if ((*f)->state == F_GRABBING) {
520                         /*previous frame is incomplete */
521                         if ((*f)->fieldbytesused < dev->field_size) {
522                                 (*f)->state = F_ERROR;
523                                 em28xx_isocdbg ("dropping incomplete bottom field (%i missing bytes)",
524                                          dev->field_size-(*f)->fieldbytesused);
525                         } else {
526                                 (*f)->state = F_DONE;
527                                 (*f)->buf.bytesused = dev->frame_size;
528                         }
529                 }
530                 if ((*f)->state == F_DONE || (*f)->state == F_ERROR) {
531                         /* move current frame to outqueue and get next free buffer from inqueue */
532                         spin_lock_irqsave(&dev-> queue_lock, *lock_flags);
533                         list_move_tail(&(*f)->frame, &dev->outqueue);
534                         if (!list_empty(&dev->inqueue))
535                                 (*f) = list_entry(dev-> inqueue.next,
536                         struct em28xx_frame_t,frame);
537                         else
538                                 (*f) = NULL;
539                         spin_unlock_irqrestore(&dev->queue_lock,*lock_flags);
540                 }
541                 if (!(*f)) {
542                         em28xx_isocdbg ("new frame but no buffer is free");
543                         return -1;
544                 }
545                 do_gettimeofday(&(*f)->buf.timestamp);
546                 (*f)->buf.sequence = ++dev->frame_count;
547                 (*f)->buf.field = V4L2_FIELD_INTERLACED;
548                 (*f)->state = F_GRABBING;
549                 (*f)->buf.bytesused = 0;
550                 (*f)->top_field = 1;
551                 (*f)->fieldbytesused = 0;
552         } else {
553                                         /* acquiring bottom field */
554                 if ((*f)->state == F_GRABBING) {
555                         if (!(*f)->top_field) {
556                                 (*f)->state = F_ERROR;
557                                 em28xx_isocdbg ("unexpected begin of bottom field; discarding it");
558                         } else if ((*f)-> fieldbytesused < dev->field_size - 172) {
559                                 (*f)->state = F_ERROR;
560                                 em28xx_isocdbg ("dropping incomplete top field (%i missing bytes)",
561                                          dev->field_size-(*f)->fieldbytesused);
562                         } else {
563                                 (*f)->top_field = 0;
564                                 (*f)->fieldbytesused = 0;
565                         }
566                 }
567         }
568         return (0);
569 }
570
571 static inline void em28xx_isoc_video_copy(struct em28xx *dev,
572                                           struct em28xx_frame_t **f, unsigned char *buf, int len)
573 {
574         void *fieldstart, *startwrite, *startread;
575         int linesdone, currlinedone, offset, lencopy,remain;
576
577         if(dev->frame_size != (*f)->buf.length){
578                 em28xx_err("frame_size %i and buf.length %i are different!!!\n",dev->frame_size,(*f)->buf.length);
579                 return;
580         }
581
582         if ((*f)->fieldbytesused + len > dev->field_size)
583                 len =dev->field_size - (*f)->fieldbytesused;
584
585         if (buf[0] != 0x88 && buf[0] != 0x22) {
586                 em28xx_isocdbg("frame is not complete\n");
587                 startread = buf;
588                 len+=4;
589         } else
590                 startread = buf + 4;
591
592         remain = len;
593
594         if ((*f)->top_field)
595                 fieldstart = (*f)->bufmem;
596         else
597                 fieldstart = (*f)->bufmem + dev->bytesperline;
598
599         linesdone = (*f)->fieldbytesused / dev->bytesperline;
600         currlinedone = (*f)->fieldbytesused % dev->bytesperline;
601         offset = linesdone * dev->bytesperline * 2 + currlinedone;
602         startwrite = fieldstart + offset;
603         lencopy = dev->bytesperline - currlinedone;
604         lencopy = lencopy > remain ? remain : lencopy;
605
606         memcpy(startwrite, startread, lencopy);
607         remain -= lencopy;
608
609         while (remain > 0) {
610                 startwrite += lencopy + dev->bytesperline;
611                 startread += lencopy;
612                 if (dev->bytesperline > remain)
613                         lencopy = remain;
614                 else
615                         lencopy = dev->bytesperline;
616
617                 memcpy(startwrite, startread, lencopy);
618                 remain -= lencopy;
619         }
620
621         (*f)->fieldbytesused += len;
622 }
623
624 /*
625  * em28xx_isoIrq()
626  * handles the incoming isoc urbs and fills the frames from our inqueue
627  */
628 static void em28xx_isocIrq(struct urb *urb)
629 {
630         struct em28xx *dev = urb->context;
631         int i, status;
632         struct em28xx_frame_t **f;
633         unsigned long lock_flags;
634
635         if (!dev)
636                 return;
637 #ifdef ENABLE_DEBUG_ISOC_FRAMES
638         if (isoc_debug>1)
639                 em28xx_isoc_dump(urb);
640 #endif
641
642         if (urb->status == -ENOENT)
643                 return;
644
645         f = &dev->frame_current;
646
647         if (dev->stream == STREAM_INTERRUPT) {
648                 dev->stream = STREAM_OFF;
649                 if ((*f))
650                         (*f)->state = F_QUEUED;
651                 em28xx_isocdbg("stream interrupted");
652                 wake_up_interruptible(&dev->wait_stream);
653         }
654
655         if ((dev->state & DEV_DISCONNECTED) || (dev->state & DEV_MISCONFIGURED))
656                 return;
657
658         if (dev->stream == STREAM_ON && !list_empty(&dev->inqueue)) {
659                 if (!(*f))
660                         (*f) = list_entry(dev->inqueue.next,
661                 struct em28xx_frame_t, frame);
662
663                 for (i = 0; i < urb->number_of_packets; i++) {
664                         unsigned char *buf = urb->transfer_buffer +
665                                         urb->iso_frame_desc[i].offset;
666                         int len = urb->iso_frame_desc[i].actual_length - 4;
667
668                         if (urb->iso_frame_desc[i].status) {
669                                 em28xx_isocdbg("data error: [%d] len=%d, status=%d", i,
670                                         urb->iso_frame_desc[i].actual_length,
671                                         urb->iso_frame_desc[i].status);
672                                 if (urb->iso_frame_desc[i].status != -EPROTO)
673                                         continue;
674                         }
675                         if (urb->iso_frame_desc[i].actual_length <= 0) {
676                                 em28xx_isocdbg("packet %d is empty",i);
677                                 continue;
678                         }
679                         if (urb->iso_frame_desc[i].actual_length >
680                             urb->iso_frame_desc[i].length) {
681                                 em28xx_isocdbg("packet bigger than packet size");
682                                 continue;
683                         }
684                         /*new frame */
685                         if (buf[0] == 0x22 && buf[1] == 0x5a) {
686                                 em28xx_isocdbg("Video frame, length=%i!",len);
687
688                                 if (em28xx_isoc_video(dev,f,&lock_flags,buf[2]))
689                                 break;
690                         } else if (buf[0]==0x33 && buf[1]==0x95 && buf[2]==0x00) {
691                                 em28xx_isocdbg("VBI HEADER!!!");
692                         }
693
694                         /* actual copying */
695                         if ((*f)->state == F_GRABBING) {
696                                 em28xx_isoc_video_copy(dev,f,buf, len);
697                         }
698                 }
699         }
700
701         for (i = 0; i < urb->number_of_packets; i++) {
702                 urb->iso_frame_desc[i].status = 0;
703                 urb->iso_frame_desc[i].actual_length = 0;
704         }
705
706         urb->status = 0;
707         if ((status = usb_submit_urb(urb, GFP_ATOMIC))) {
708                 em28xx_errdev("resubmit of urb failed (error=%i)\n", status);
709                 dev->state |= DEV_MISCONFIGURED;
710         }
711         wake_up_interruptible(&dev->wait_frame);
712         return;
713 }
714
715 /*
716  * em28xx_uninit_isoc()
717  * deallocates the buffers and urbs allocated during em28xx_init_iosc()
718  */
719 void em28xx_uninit_isoc(struct em28xx *dev)
720 {
721         int i;
722
723         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
724                 if (dev->urb[i]) {
725                         usb_kill_urb(dev->urb[i]);
726                         if (dev->transfer_buffer[i]) {
727                                 usb_buffer_free(dev->udev,
728                                                 dev->urb[i]->transfer_buffer_length,
729                                                 dev->transfer_buffer[i],
730                                                 dev->urb[i]->transfer_dma);
731                         }
732                         usb_free_urb(dev->urb[i]);
733                 }
734                 dev->urb[i] = NULL;
735                 dev->transfer_buffer[i] = NULL;
736         }
737         em28xx_capture_start(dev, 0);
738 }
739
740 /*
741  * em28xx_init_isoc()
742  * allocates transfer buffers and submits the urbs for isoc transfer
743  */
744 int em28xx_init_isoc(struct em28xx *dev)
745 {
746         /* change interface to 3 which allows the biggest packet sizes */
747         int i, errCode;
748         int sb_size;
749
750         em28xx_set_alternate(dev);
751         sb_size = EM28XX_NUM_PACKETS * dev->max_pkt_size;
752
753         /* reset streaming vars */
754         dev->frame_current = NULL;
755         dev->frame_count = 0;
756
757         /* allocate urbs */
758         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
759                 struct urb *urb;
760                 int j;
761                 /* allocate transfer buffer */
762                 urb = usb_alloc_urb(EM28XX_NUM_PACKETS, GFP_KERNEL);
763                 if (!urb){
764                         em28xx_errdev("cannot alloc urb %i\n", i);
765                         em28xx_uninit_isoc(dev);
766                         return -ENOMEM;
767                 }
768                 dev->transfer_buffer[i] = usb_buffer_alloc(dev->udev, sb_size,
769                                                            GFP_KERNEL,
770                                                            &urb->transfer_dma);
771                 if (!dev->transfer_buffer[i]) {
772                         em28xx_errdev
773                                         ("unable to allocate %i bytes for transfer buffer %i\n",
774                                          sb_size, i);
775                         em28xx_uninit_isoc(dev);
776                         usb_free_urb(urb);
777                         return -ENOMEM;
778                 }
779                 memset(dev->transfer_buffer[i], 0, sb_size);
780                 urb->dev = dev->udev;
781                 urb->context = dev;
782                 urb->pipe = usb_rcvisocpipe(dev->udev, 0x82);
783                 urb->transfer_flags = URB_ISO_ASAP;
784                 urb->interval = 1;
785                 urb->transfer_buffer = dev->transfer_buffer[i];
786                 urb->complete = em28xx_isocIrq;
787                 urb->number_of_packets = EM28XX_NUM_PACKETS;
788                 urb->transfer_buffer_length = sb_size;
789                 for (j = 0; j < EM28XX_NUM_PACKETS; j++) {
790                         urb->iso_frame_desc[j].offset = j * dev->max_pkt_size;
791                         urb->iso_frame_desc[j].length = dev->max_pkt_size;
792                 }
793                 dev->urb[i] = urb;
794         }
795
796         /* submit urbs */
797         em28xx_coredbg("Submitting %d urbs of %d packets (%d each)\n",
798                        EM28XX_NUM_BUFS, EM28XX_NUM_PACKETS, dev->max_pkt_size);
799         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
800                 errCode = usb_submit_urb(dev->urb[i], GFP_KERNEL);
801                 if (errCode) {
802                         em28xx_errdev("submit of urb %i failed (error=%i)\n", i,
803                                       errCode);
804                         em28xx_uninit_isoc(dev);
805                         return errCode;
806                 }
807         }
808
809         return 0;
810 }
811
812 int em28xx_set_alternate(struct em28xx *dev)
813 {
814         int errCode, prev_alt = dev->alt;
815         int i;
816         unsigned int min_pkt_size = dev->bytesperline+4;
817
818         /* When image size is bigger than a ceirtain value,
819            the frame size should be increased, otherwise, only
820            green screen will be received.
821          */
822         if (dev->frame_size > 720*240*2)
823                 min_pkt_size *= 2;
824
825         for (i = 0; i < dev->num_alt; i++)
826                 if (dev->alt_max_pkt_size[i] >= min_pkt_size)
827                         break;
828         dev->alt = i;
829
830         if (dev->alt != prev_alt) {
831                 em28xx_coredbg("minimum isoc packet size: %u (alt=%d)\n",
832                                 min_pkt_size, dev->alt);
833                 dev->max_pkt_size = dev->alt_max_pkt_size[dev->alt];
834                 em28xx_coredbg("setting alternate %d with wMaxPacketSize=%u\n",
835                                dev->alt, dev->max_pkt_size);
836                 errCode = usb_set_interface(dev->udev, 0, dev->alt);
837                 if (errCode < 0) {
838                         em28xx_errdev ("cannot change alternate number to %d (error=%i)\n",
839                                         dev->alt, errCode);
840                         return errCode;
841                 }
842         }
843         return 0;
844 }