git.oblomov.eu Git - linux-2.6/blob - 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         em28xx_regdbg("req=%02x, reg=%02x ", req, reg);
 143
 144         ret = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0), req,
 145                               USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 146                               0x0000, reg, buf, len, HZ);
 147
 148         if (reg_debug){
 149                 printk(ret < 0 ? " failed!\n" : "%02x values: ", ret);
 150                 for (byte = 0; byte < len; byte++) {
 151                         printk(" %02x", buf[byte]);
 152                 }
 153                 printk("\n");
 154         }
 155
 156         return ret;
 157 }
 158
 159 /*
 160  * em28xx_read_reg_req()
 161  * reads data from the usb device specifying bRequest
 162  */
 163 int em28xx_read_reg_req(struct em28xx *dev, u8 req, u16 reg)
 164 {
 165         u8 val;
 166         int ret;
 167
 168         em28xx_regdbg("req=%02x, reg=%02x:", req, reg);
 169
 170         ret = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0), req,
 171                               USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 172                               0x0000, reg, &val, 1, HZ);
 173
 174         if (reg_debug)
 175                 printk(ret < 0 ? " failed!\n" : "%02x\n", val);
 176
 177         if (ret < 0)
 178                 return ret;
 179
 180         return val;
 181 }
 182
 183 int em28xx_read_reg(struct em28xx *dev, u16 reg)
 184 {
 185         return em28xx_read_reg_req(dev, USB_REQ_GET_STATUS, reg);
 186 }
 187
 188 /*
 189  * em28xx_write_regs_req()
 190  * sends data to the usb device, specifying bRequest
 191  */
 192 int em28xx_write_regs_req(struct em28xx *dev, u8 req, u16 reg, char *buf,
 193                                  int len)
 194 {
 195         int ret;
 196
 197         /*usb_control_msg seems to expect a kmalloced buffer */
 198         unsigned char *bufs = kmalloc(len, GFP_KERNEL);
 199
 200         em28xx_regdbg("req=%02x reg=%02x:", req, reg);
 201
 202         if (reg_debug) {
 203                 int i;
 204                 for (i = 0; i < len; ++i)
 205                         printk (" %02x", (unsigned char)buf[i]);
 206                 printk ("\n");
 207         }
 208
 209         if (!bufs)
 210                 return -ENOMEM;
 211         memcpy(bufs, buf, len);
 212         ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0), req,
 213                               USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 214                               0x0000, reg, bufs, len, HZ);
 215         mdelay(5);              /* FIXME: magic number */
 216         kfree(bufs);
 217         return ret;
 218 }
 219
 220 int em28xx_write_regs(struct em28xx *dev, u16 reg, char *buf, int len)
 221 {
 222         return em28xx_write_regs_req(dev, USB_REQ_GET_STATUS, reg, buf, len);
 223 }
 224
 225 /*
 226  * em28xx_write_reg_bits()
 227  * sets only some bits (specified by bitmask) of a register, by first reading
 228  * the actual value
 229  */
 230 int em28xx_write_reg_bits(struct em28xx *dev, u16 reg, u8 val,
 231                                  u8 bitmask)
 232 {
 233         int oldval;
 234         u8 newval;
 235         if ((oldval = em28xx_read_reg(dev, reg)) < 0)
 236                 return oldval;
 237         newval = (((u8) oldval) & ~bitmask) | (val & bitmask);
 238         return em28xx_write_regs(dev, reg, &newval, 1);
 239 }
 240
 241 /*
 242  * em28xx_write_ac97()
 243  * write a 16 bit value to the specified AC97 address (LSB first!)
 244  */
 245 int em28xx_write_ac97(struct em28xx *dev, u8 reg, u8 * val)
 246 {
 247         int ret;
 248         u8 addr = reg & 0x7f;
 249         if ((ret = em28xx_write_regs(dev, AC97LSB_REG, val, 2)) < 0)
 250                 return ret;
 251         if ((ret = em28xx_write_regs(dev, AC97ADDR_REG, &addr, 1)) < 0)
 252                 return ret;
 253         if ((ret = em28xx_read_reg(dev, AC97BUSY_REG)) < 0)
 254                 return ret;
 255         else if (((u8) ret) & 0x01) {
 256                 em28xx_warn ("AC97 command still being exectuted: not handled properly!\n");
 257         }
 258         return 0;
 259 }
 260
 261 int em28xx_audio_analog_set(struct em28xx *dev)
 262 {
 263         char s[2] = { 0x00, 0x00 };
 264         s[0] |= 0x1f - dev->volume;
 265         s[1] |= 0x1f - dev->volume;
 266         if (dev->mute)
 267                 s[1] |= 0x80;
 268         return em28xx_write_ac97(dev, MASTER_AC97, s);
 269 }
 270
 271
 272 int em28xx_colorlevels_set_default(struct em28xx *dev)
 273 {
 274         em28xx_write_regs(dev, YGAIN_REG, "\x10", 1);   /* contrast */
 275         em28xx_write_regs(dev, YOFFSET_REG, "\x00", 1); /* brightness */
 276         em28xx_write_regs(dev, UVGAIN_REG, "\x10", 1);  /* saturation */
 277         em28xx_write_regs(dev, UOFFSET_REG, "\x00", 1);
 278         em28xx_write_regs(dev, VOFFSET_REG, "\x00", 1);
 279         em28xx_write_regs(dev, SHARPNESS_REG, "\x00", 1);
 280
 281         em28xx_write_regs(dev, GAMMA_REG, "\x20", 1);
 282         em28xx_write_regs(dev, RGAIN_REG, "\x20", 1);
 283         em28xx_write_regs(dev, GGAIN_REG, "\x20", 1);
 284         em28xx_write_regs(dev, BGAIN_REG, "\x20", 1);
 285         em28xx_write_regs(dev, ROFFSET_REG, "\x00", 1);
 286         em28xx_write_regs(dev, GOFFSET_REG, "\x00", 1);
 287         return em28xx_write_regs(dev, BOFFSET_REG, "\x00", 1);
 288 }
 289
 290 int em28xx_capture_start(struct em28xx *dev, int start)
 291 {
 292         int ret;
 293         /* FIXME: which is the best order? */
 294         /* video registers are sampled by VREF */
 295         if ((ret = em28xx_write_reg_bits(dev, USBSUSP_REG, start ? 0x10 : 0x00,
 296                                           0x10)) < 0)
 297                 return ret;
 298         /* enable video capture */
 299         return em28xx_write_regs(dev, VINENABLE_REG, start ? "\x67" : "\x27", 1);
 300 }
 301
 302 int em28xx_outfmt_set_yuv422(struct em28xx *dev)
 303 {
 304         em28xx_write_regs(dev, OUTFMT_REG, "\x34", 1);
 305         em28xx_write_regs(dev, VINMODE_REG, "\x10", 1);
 306         return em28xx_write_regs(dev, VINCTRL_REG, "\x11", 1);
 307 }
 308
 309 int em28xx_accumulator_set(struct em28xx *dev, u8 xmin, u8 xmax, u8 ymin,
 310                                   u8 ymax)
 311 {
 312         em28xx_coredbg("em28xx Scale: (%d,%d)-(%d,%d)\n", xmin, ymin, xmax, ymax);
 313
 314         em28xx_write_regs(dev, XMIN_REG, &xmin, 1);
 315         em28xx_write_regs(dev, XMAX_REG, &xmax, 1);
 316         em28xx_write_regs(dev, YMIN_REG, &ymin, 1);
 317         return em28xx_write_regs(dev, YMAX_REG, &ymax, 1);
 318 }
 319
 320 int em28xx_capture_area_set(struct em28xx *dev, u8 hstart, u8 vstart,
 321                                    u16 width, u16 height)
 322 {
 323         u8 cwidth = width;
 324         u8 cheight = height;
 325         u8 overflow = (height >> 7 & 0x02) | (width >> 8 & 0x01);
 326
 327         em28xx_coredbg("em28xx Area Set: (%d,%d)\n", (width | (overflow & 2) << 7),
 328                         (height | (overflow & 1) << 8));
 329
 330         em28xx_write_regs(dev, HSTART_REG, &hstart, 1);
 331         em28xx_write_regs(dev, VSTART_REG, &vstart, 1);
 332         em28xx_write_regs(dev, CWIDTH_REG, &cwidth, 1);
 333         em28xx_write_regs(dev, CHEIGHT_REG, &cheight, 1);
 334         return em28xx_write_regs(dev, OFLOW_REG, &overflow, 1);
 335 }
 336
 337 int em28xx_scaler_set(struct em28xx *dev, u16 h, u16 v)
 338 {
 339         u8 mode;
 340         /* the em2800 scaler only supports scaling down to 50% */
 341         if(dev->is_em2800)
 342                 mode = (v ? 0x20 : 0x00) | (h ? 0x10 : 0x00);
 343         else {
 344                 u8 buf[2];
 345                 buf[0] = h;
 346                 buf[1] = h >> 8;
 347                 em28xx_write_regs(dev, HSCALELOW_REG, (char *)buf, 2);
 348                 buf[0] = v;
 349                 buf[1] = v >> 8;
 350                 em28xx_write_regs(dev, VSCALELOW_REG, (char *)buf, 2);
 351                 /* it seems that both H and V scalers must be active to work correctly */
 352                 mode = (h || v)? 0x30: 0x00;
 353         }
 354         return em28xx_write_reg_bits(dev, COMPR_REG, mode, 0x30);
 355 }
 356
 357 /* FIXME: this only function read values from dev */
 358 int em28xx_resolution_set(struct em28xx *dev)
 359 {
 360         int width, height;
 361         width = norm_maxw(dev);
 362         height = norm_maxh(dev) >> 1;
 363
 364         em28xx_outfmt_set_yuv422(dev);
 365         em28xx_accumulator_set(dev, 1, (width - 4) >> 2, 1, (height - 4) >> 2);
 366         em28xx_capture_area_set(dev, 0, 0, width >> 2, height >> 2);
 367         return em28xx_scaler_set(dev, dev->hscale, dev->vscale);
 368 }
 369
 370
 371 /******************* isoc transfer handling ****************************/
 372
 373 #ifdef ENABLE_DEBUG_ISOC_FRAMES
 374 static void em28xx_isoc_dump(struct urb *urb, struct pt_regs *regs)
 375 {
 376         int len = 0;
 377         int ntrans = 0;
 378         int i;
 379
 380         printk(KERN_DEBUG "isocIrq: sf=%d np=%d ec=%x\n",
 381                urb->start_frame, urb->number_of_packets,
 382                urb->error_count);
 383         for (i = 0; i < urb->number_of_packets; i++) {
 384                 unsigned char *buf =
 385                                 urb->transfer_buffer +
 386                                 urb->iso_frame_desc[i].offset;
 387                 int alen = urb->iso_frame_desc[i].actual_length;
 388                 if (alen > 0) {
 389                         if (buf[0] == 0x88) {
 390                                 ntrans++;
 391                                 len += alen;
 392                         } else if (buf[0] == 0x22) {
 393                                 printk(KERN_DEBUG
 394                                                 "= l=%d nt=%d bpp=%d\n",
 395                                 len - 4 * ntrans, ntrans,
 396                                 ntrans == 0 ? 0 : len / ntrans);
 397                                 ntrans = 1;
 398                                 len = alen;
 399                         } else
 400                                 printk(KERN_DEBUG "!\n");
 401                 }
 402                 printk(KERN_DEBUG "   n=%d s=%d al=%d %x\n", i,
 403                        urb->iso_frame_desc[i].status,
 404                        urb->iso_frame_desc[i].actual_length,
 405                        (unsigned int)
 406                                        *((unsigned char *)(urb->transfer_buffer +
 407                                        urb->iso_frame_desc[i].
 408                                        offset)));
 409         }
 410 }
 411 #endif
 412
 413 static inline int em28xx_isoc_video(struct em28xx *dev,struct em28xx_frame_t **f,
 414                                     unsigned long *lock_flags, unsigned char buf)
 415 {
 416         if (!(buf & 0x01)) {
 417                 if ((*f)->state == F_GRABBING) {
 418                         /*previous frame is incomplete */
 419                         if ((*f)->fieldbytesused < dev->field_size) {
 420                                 (*f)->state = F_ERROR;
 421                                 em28xx_isocdbg ("dropping incomplete bottom field (%i missing bytes)",
 422                                          dev->field_size-(*f)->fieldbytesused);
 423                         } else {
 424                                 (*f)->state = F_DONE;
 425                                 (*f)->buf.bytesused = dev->frame_size;
 426                         }
 427                 }
 428                 if ((*f)->state == F_DONE || (*f)->state == F_ERROR) {
 429                         /* move current frame to outqueue and get next free buffer from inqueue */
 430                         spin_lock_irqsave(&dev-> queue_lock, *lock_flags);
 431                         list_move_tail(&(*f)->frame, &dev->outqueue);
 432                         if (!list_empty(&dev->inqueue))
 433                                 (*f) = list_entry(dev-> inqueue.next,
 434                         struct em28xx_frame_t,frame);
 435                         else
 436                                 (*f) = NULL;
 437                         spin_unlock_irqrestore(&dev->queue_lock,*lock_flags);
 438                 }
 439                 if (!(*f)) {
 440                         em28xx_isocdbg ("new frame but no buffer is free");
 441                         return -1;
 442                 }
 443                 do_gettimeofday(&(*f)->buf.timestamp);
 444                 (*f)->buf.sequence = ++dev->frame_count;
 445                 (*f)->buf.field = V4L2_FIELD_INTERLACED;
 446                 (*f)->state = F_GRABBING;
 447                 (*f)->buf.bytesused = 0;
 448                 (*f)->top_field = 1;
 449                 (*f)->fieldbytesused = 0;
 450         } else {
 451                                         /* acquiring bottom field */
 452                 if ((*f)->state == F_GRABBING) {
 453                         if (!(*f)->top_field) {
 454                                 (*f)->state = F_ERROR;
 455                                 em28xx_isocdbg ("unexpected begin of bottom field; discarding it");
 456                         } else if ((*f)-> fieldbytesused < dev->field_size - 172) {
 457                                 (*f)->state = F_ERROR;
 458                                 em28xx_isocdbg ("dropping incomplete top field (%i missing bytes)",
 459                                          dev->field_size-(*f)->fieldbytesused);
 460                         } else {
 461                                 (*f)->top_field = 0;
 462                                 (*f)->fieldbytesused = 0;
 463                         }
 464                 }
 465         }
 466         return (0);
 467 }
 468
 469 static inline void em28xx_isoc_video_copy(struct em28xx *dev,
 470                                           struct em28xx_frame_t **f, unsigned char *buf, int len)
 471 {
 472         void *fieldstart, *startwrite, *startread;
 473         int linesdone, currlinedone, offset, lencopy,remain;
 474
 475         if(dev->frame_size != (*f)->buf.length){
 476                 em28xx_err("frame_size %i and buf.length %i are different!!!\n",dev->frame_size,(*f)->buf.length);
 477                 return;
 478         }
 479
 480         if ((*f)->fieldbytesused + len > dev->field_size)
 481                 len =dev->field_size - (*f)->fieldbytesused;
 482
 483         if (buf[0] != 0x88 && buf[0] != 0x22) {
 484                 em28xx_isocdbg("frame is not complete\n");
 485                 startread = buf;
 486                 len+=4;
 487         } else
 488                 startread = buf + 4;
 489
 490         remain = len;
 491
 492         if ((*f)->top_field)
 493                 fieldstart = (*f)->bufmem;
 494         else
 495                 fieldstart = (*f)->bufmem + dev->bytesperline;
 496
 497         linesdone = (*f)->fieldbytesused / dev->bytesperline;
 498         currlinedone = (*f)->fieldbytesused % dev->bytesperline;
 499         offset = linesdone * dev->bytesperline * 2 + currlinedone;
 500         startwrite = fieldstart + offset;
 501         lencopy = dev->bytesperline - currlinedone;
 502         lencopy = lencopy > remain ? remain : lencopy;
 503
 504         memcpy(startwrite, startread, lencopy);
 505         remain -= lencopy;
 506
 507         while (remain > 0) {
 508                 startwrite += lencopy + dev->bytesperline;
 509                 startread += lencopy;
 510                 if (dev->bytesperline > remain)
 511                         lencopy = remain;
 512                 else
 513                         lencopy = dev->bytesperline;
 514
 515                 memcpy(startwrite, startread, lencopy);
 516                 remain -= lencopy;
 517         }
 518
 519         (*f)->fieldbytesused += len;
 520 }
 521
 522 /*
 523  * em28xx_isoIrq()
 524  * handles the incoming isoc urbs and fills the frames from our inqueue
 525  */
 526 void em28xx_isocIrq(struct urb *urb, struct pt_regs *regs)
 527 {
 528         struct em28xx *dev = urb->context;
 529         int i, status;
 530         struct em28xx_frame_t **f;
 531         unsigned long lock_flags;
 532
 533         if (!dev)
 534                 return;
 535 #ifdef ENABLE_DEBUG_ISOC_FRAMES
 536         if (isoc_debug>1)
 537                 em28xx_isoc_dump(urb, regs);
 538 #endif
 539
 540         if (urb->status == -ENOENT)
 541                 return;
 542
 543         f = &dev->frame_current;
 544
 545         if (dev->stream == STREAM_INTERRUPT) {
 546                 dev->stream = STREAM_OFF;
 547                 if ((*f))
 548                         (*f)->state = F_QUEUED;
 549                 em28xx_isocdbg("stream interrupted");
 550                 wake_up_interruptible(&dev->wait_stream);
 551         }
 552
 553         if ((dev->state & DEV_DISCONNECTED) || (dev->state & DEV_MISCONFIGURED))
 554                 return;
 555
 556         if (dev->stream == STREAM_ON && !list_empty(&dev->inqueue)) {
 557                 if (!(*f))
 558                         (*f) = list_entry(dev->inqueue.next,
 559                 struct em28xx_frame_t, frame);
 560
 561                 for (i = 0; i < urb->number_of_packets; i++) {
 562                         unsigned char *buf = urb->transfer_buffer +
 563                                         urb->iso_frame_desc[i].offset;
 564                         int len = urb->iso_frame_desc[i].actual_length - 4;
 565
 566                         if (urb->iso_frame_desc[i].status) {
 567                                 em28xx_isocdbg("data error: [%d] len=%d, status=%d", i,
 568                                         urb->iso_frame_desc[i].actual_length,
 569                                         urb->iso_frame_desc[i].status);
 570                                 if (urb->iso_frame_desc[i].status != -EPROTO)
 571                                         continue;
 572                         }
 573                         if (urb->iso_frame_desc[i].actual_length <= 0) {
 574                                 em28xx_isocdbg("packet %d is empty",i);
 575                                 continue;
 576                         }
 577                         if (urb->iso_frame_desc[i].actual_length >
 578                                                  dev->max_pkt_size) {
 579                                 em28xx_isocdbg("packet bigger than packet size");
 580                                 continue;
 581                         }
 582                         /*new frame */
 583                         if (buf[0] == 0x22 && buf[1] == 0x5a) {
 584                                 em28xx_isocdbg("Video frame, length=%i!",len);
 585
 586                                 if (em28xx_isoc_video(dev,f,&lock_flags,buf[2]))
 587                                 break;
 588                         } else if (buf[0]==0x33 && buf[1]==0x95 && buf[2]==0x00) {
 589                                 em28xx_isocdbg("VBI HEADER!!!");
 590                         }
 591
 592                         /* actual copying */
 593                         if ((*f)->state == F_GRABBING) {
 594                                 em28xx_isoc_video_copy(dev,f,buf, len);
 595                         }
 596                 }
 597         }
 598
 599         for (i = 0; i < urb->number_of_packets; i++) {
 600                 urb->iso_frame_desc[i].status = 0;
 601                 urb->iso_frame_desc[i].actual_length = 0;
 602         }
 603
 604         urb->status = 0;
 605         if ((status = usb_submit_urb(urb, GFP_ATOMIC))) {
 606                 em28xx_errdev("resubmit of urb failed (error=%i)\n", status);
 607                 dev->state |= DEV_MISCONFIGURED;
 608         }
 609         wake_up_interruptible(&dev->wait_frame);
 610         return;
 611 }
 612
 613 /*
 614  * em28xx_uninit_isoc()
 615  * deallocates the buffers and urbs allocated during em28xx_init_iosc()
 616  */
 617 void em28xx_uninit_isoc(struct em28xx *dev)
 618 {
 619         int i;
 620
 621         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
 622                 if (dev->urb[i]) {
 623                         usb_kill_urb(dev->urb[i]);
 624                         if (dev->transfer_buffer[i]){
 625                                 usb_buffer_free(dev->udev,(EM28XX_NUM_PACKETS*dev->max_pkt_size),dev->transfer_buffer[i],dev->urb[i]->transfer_dma);
 626                         }
 627                         usb_free_urb(dev->urb[i]);
 628                 }
 629                 dev->urb[i] = NULL;
 630                 dev->transfer_buffer[i] = NULL;
 631         }
 632         em28xx_capture_start(dev, 0);
 633 }
 634
 635 /*
 636  * em28xx_init_isoc()
 637  * allocates transfer buffers and submits the urbs for isoc transfer
 638  */
 639 int em28xx_init_isoc(struct em28xx *dev)
 640 {
 641         /* change interface to 3 which allowes the biggest packet sizes */
 642         int i, errCode;
 643         const int sb_size = EM28XX_NUM_PACKETS * dev->max_pkt_size;
 644
 645         /* reset streaming vars */
 646         dev->frame_current = NULL;
 647         dev->frame_count = 0;
 648
 649         /* allocate urbs */
 650         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
 651                 struct urb *urb;
 652                 int j, k;
 653                 /* allocate transfer buffer */
 654                 urb = usb_alloc_urb(EM28XX_NUM_PACKETS, GFP_KERNEL);
 655                 if (!urb){
 656                         em28xx_errdev("cannot alloc urb %i\n", i);
 657                         em28xx_uninit_isoc(dev);
 658                         return -ENOMEM;
 659                 }
 660                 dev->transfer_buffer[i] = usb_buffer_alloc(dev->udev, sb_size, GFP_KERNEL,&urb->transfer_dma);
 661                 if (!dev->transfer_buffer[i]) {
 662                         em28xx_errdev
 663                                         ("unable to allocate %i bytes for transfer buffer %i\n",
 664                                          sb_size, i);
 665                         em28xx_uninit_isoc(dev);
 666                         return -ENOMEM;
 667                 }
 668                 memset(dev->transfer_buffer[i], 0, sb_size);
 669                 urb->dev = dev->udev;
 670                 urb->context = dev;
 671                 urb->pipe = usb_rcvisocpipe(dev->udev, 0x82);
 672                 urb->transfer_flags = URB_ISO_ASAP;
 673                 urb->interval = 1;
 674                 urb->transfer_buffer = dev->transfer_buffer[i];
 675                 urb->complete = em28xx_isocIrq;
 676                 urb->number_of_packets = EM28XX_NUM_PACKETS;
 677                 urb->transfer_buffer_length = sb_size;
 678                 for (j = k = 0; j < EM28XX_NUM_PACKETS;
 679                                 j++, k += dev->max_pkt_size) {
 680                         urb->iso_frame_desc[j].offset = k;
 681                         urb->iso_frame_desc[j].length =
 682                                 dev->max_pkt_size;
 683                 }
 684                 dev->urb[i] = urb;
 685         }
 686
 687         /* submit urbs */
 688         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
 689                 errCode = usb_submit_urb(dev->urb[i], GFP_KERNEL);
 690                 if (errCode) {
 691                         em28xx_errdev("submit of urb %i failed (error=%i)\n", i,
 692                                       errCode);
 693                         em28xx_uninit_isoc(dev);
 694                         return errCode;
 695                 }
 696         }
 697
 698         return 0;
 699 }
 700
 701 int em28xx_set_alternate(struct em28xx *dev)
 702 {
 703         int errCode, prev_alt = dev->alt;
 704         dev->alt = alt;
 705         if (dev->alt == 0) {
 706                 int i;
 707                 for(i=0;i< dev->num_alt; i++)
 708                         if(dev->alt_max_pkt_size[i]>dev->alt_max_pkt_size[dev->alt])
 709                                 dev->alt=i;
 710         }
 711
 712         if (dev->alt != prev_alt) {
 713                 dev->max_pkt_size = dev->alt_max_pkt_size[dev->alt];
 714                 em28xx_coredbg("setting alternate %d with wMaxPacketSize=%u\n", dev->alt,
 715                        dev->max_pkt_size);
 716                 errCode = usb_set_interface(dev->udev, 0, dev->alt);
 717                 if (errCode < 0) {
 718                         em28xx_errdev ("cannot change alternate number to %d (error=%i)\n",
 719                                                         dev->alt, errCode);
 720                         return errCode;
 721                 }
 722         }
 723         return 0;
 724 }