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", count, imagesize);
  76         if (count > EM28XX_NUM_FRAMES)
  77                 count = EM28XX_NUM_FRAMES;
  78
  79         dev->num_frames = count;
  80         while (dev->num_frames > 0) {
  81                 if ((buff = vmalloc_32(dev->num_frames * imagesize))) {
  82                         memset(buff, 0, dev->num_frames * imagesize);
  83                         break;
  84                 }
  85                 dev->num_frames--;
  86         }
  87
  88         for (i = 0; i < dev->num_frames; i++) {
  89                 dev->frame[i].bufmem = buff + i * imagesize;
  90                 dev->frame[i].buf.index = i;
  91                 dev->frame[i].buf.m.offset = i * imagesize;
  92                 dev->frame[i].buf.length = dev->frame_size;
  93                 dev->frame[i].buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
  94                 dev->frame[i].buf.sequence = 0;
  95                 dev->frame[i].buf.field = V4L2_FIELD_NONE;
  96                 dev->frame[i].buf.memory = V4L2_MEMORY_MMAP;
  97                 dev->frame[i].buf.flags = 0;
  98         }
  99         return dev->num_frames;
 100 }
 101
 102 /*
 103  * em28xx_queue_unusedframes()
 104  * add all frames that are not currently in use to the inbuffer queue
 105  */
 106 void em28xx_queue_unusedframes(struct em28xx *dev)
 107 {
 108         unsigned long lock_flags;
 109         u32 i;
 110
 111         for (i = 0; i < dev->num_frames; i++)
 112                 if (dev->frame[i].state == F_UNUSED) {
 113                         dev->frame[i].state = F_QUEUED;
 114                         spin_lock_irqsave(&dev->queue_lock, lock_flags);
 115                         list_add_tail(&dev->frame[i].frame, &dev->inqueue);
 116                         spin_unlock_irqrestore(&dev->queue_lock, lock_flags);
 117                 }
 118 }
 119
 120 /*
 121  * em28xx_release_buffers()
 122  * free frame buffers
 123  */
 124 void em28xx_release_buffers(struct em28xx *dev)
 125 {
 126         if (dev->num_frames) {
 127                 vfree(dev->frame[0].bufmem);
 128                 dev->num_frames = 0;
 129         }
 130 }
 131
 132 /*
 133  * em28xx_read_reg_req()
 134  * reads data from the usb device specifying bRequest
 135  */
 136 int em28xx_read_reg_req_len(struct em28xx *dev, u8 req, u16 reg,
 137                                    char *buf, int len)
 138 {
 139         int ret, byte;
 140
 141         if (dev->state & DEV_DISCONNECTED)
 142                 return(-ENODEV);
 143
 144         em28xx_regdbg("req=%02x, reg=%02x ", req, reg);
 145
 146         ret = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0), req,
 147                               USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 148                               0x0000, reg, buf, len, HZ);
 149
 150         if (reg_debug){
 151                 printk(ret < 0 ? " failed!\n" : "%02x values: ", ret);
 152                 for (byte = 0; byte < len; byte++) {
 153                         printk(" %02x", buf[byte]);
 154                 }
 155                 printk("\n");
 156         }
 157
 158         return ret;
 159 }
 160
 161 /*
 162  * em28xx_read_reg_req()
 163  * reads data from the usb device specifying bRequest
 164  */
 165 int em28xx_read_reg_req(struct em28xx *dev, u8 req, u16 reg)
 166 {
 167         u8 val;
 168         int ret;
 169
 170         if (dev->state & DEV_DISCONNECTED)
 171                 return(-ENODEV);
 172
 173         em28xx_regdbg("req=%02x, reg=%02x:", req, reg);
 174
 175         ret = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0), req,
 176                               USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 177                               0x0000, reg, &val, 1, HZ);
 178
 179         if (reg_debug)
 180                 printk(ret < 0 ? " failed!\n" : "%02x\n", val);
 181
 182         if (ret < 0)
 183                 return ret;
 184
 185         return val;
 186 }
 187
 188 int em28xx_read_reg(struct em28xx *dev, u16 reg)
 189 {
 190         return em28xx_read_reg_req(dev, USB_REQ_GET_STATUS, reg);
 191 }
 192
 193 /*
 194  * em28xx_write_regs_req()
 195  * sends data to the usb device, specifying bRequest
 196  */
 197 int em28xx_write_regs_req(struct em28xx *dev, u8 req, u16 reg, char *buf,
 198                                  int len)
 199 {
 200         int ret;
 201
 202         /*usb_control_msg seems to expect a kmalloced buffer */
 203         unsigned char *bufs;
 204
 205         if (dev->state & DEV_DISCONNECTED)
 206                 return(-ENODEV);
 207
 208         bufs = kmalloc(len, GFP_KERNEL);
 209
 210         em28xx_regdbg("req=%02x reg=%02x:", req, reg);
 211
 212         if (reg_debug) {
 213                 int i;
 214                 for (i = 0; i < len; ++i)
 215                         printk (" %02x", (unsigned char)buf[i]);
 216                 printk ("\n");
 217         }
 218
 219         if (!bufs)
 220                 return -ENOMEM;
 221         memcpy(bufs, buf, len);
 222         ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0), req,
 223                               USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 224                               0x0000, reg, bufs, len, HZ);
 225         msleep(5);              /* FIXME: magic number */
 226         kfree(bufs);
 227         return ret;
 228 }
 229
 230 int em28xx_write_regs(struct em28xx *dev, u16 reg, char *buf, int len)
 231 {
 232         return em28xx_write_regs_req(dev, USB_REQ_GET_STATUS, reg, buf, len);
 233 }
 234
 235 /*
 236  * em28xx_write_reg_bits()
 237  * sets only some bits (specified by bitmask) of a register, by first reading
 238  * the actual value
 239  */
 240 int em28xx_write_reg_bits(struct em28xx *dev, u16 reg, u8 val,
 241                                  u8 bitmask)
 242 {
 243         int oldval;
 244         u8 newval;
 245         if ((oldval = em28xx_read_reg(dev, reg)) < 0)
 246                 return oldval;
 247         newval = (((u8) oldval) & ~bitmask) | (val & bitmask);
 248         return em28xx_write_regs(dev, reg, &newval, 1);
 249 }
 250
 251 /*
 252  * em28xx_write_ac97()
 253  * write a 16 bit value to the specified AC97 address (LSB first!)
 254  */
 255 int em28xx_write_ac97(struct em28xx *dev, u8 reg, u8 * val)
 256 {
 257         int ret;
 258         u8 addr = reg & 0x7f;
 259         if ((ret = em28xx_write_regs(dev, AC97LSB_REG, val, 2)) < 0)
 260                 return ret;
 261         if ((ret = em28xx_write_regs(dev, AC97ADDR_REG, &addr, 1)) < 0)
 262                 return ret;
 263         if ((ret = em28xx_read_reg(dev, AC97BUSY_REG)) < 0)
 264                 return ret;
 265         else if (((u8) ret) & 0x01) {
 266                 em28xx_warn ("AC97 command still being executed: not handled properly!\n");
 267         }
 268         return 0;
 269 }
 270
 271 int em28xx_audio_analog_set(struct em28xx *dev)
 272 {
 273         char s[2] = { 0x00, 0x00 };
 274         s[0] |= 0x1f - dev->volume;
 275         s[1] |= 0x1f - dev->volume;
 276         if (dev->mute)
 277                 s[1] |= 0x80;
 278         return em28xx_write_ac97(dev, MASTER_AC97, s);
 279 }
 280
 281
 282 int em28xx_colorlevels_set_default(struct em28xx *dev)
 283 {
 284         em28xx_write_regs(dev, YGAIN_REG, "\x10", 1);   /* contrast */
 285         em28xx_write_regs(dev, YOFFSET_REG, "\x00", 1); /* brightness */
 286         em28xx_write_regs(dev, UVGAIN_REG, "\x10", 1);  /* saturation */
 287         em28xx_write_regs(dev, UOFFSET_REG, "\x00", 1);
 288         em28xx_write_regs(dev, VOFFSET_REG, "\x00", 1);
 289         em28xx_write_regs(dev, SHARPNESS_REG, "\x00", 1);
 290
 291         em28xx_write_regs(dev, GAMMA_REG, "\x20", 1);
 292         em28xx_write_regs(dev, RGAIN_REG, "\x20", 1);
 293         em28xx_write_regs(dev, GGAIN_REG, "\x20", 1);
 294         em28xx_write_regs(dev, BGAIN_REG, "\x20", 1);
 295         em28xx_write_regs(dev, ROFFSET_REG, "\x00", 1);
 296         em28xx_write_regs(dev, GOFFSET_REG, "\x00", 1);
 297         return em28xx_write_regs(dev, BOFFSET_REG, "\x00", 1);
 298 }
 299
 300 int em28xx_capture_start(struct em28xx *dev, int start)
 301 {
 302         int ret;
 303         /* FIXME: which is the best order? */
 304         /* video registers are sampled by VREF */
 305         if ((ret = em28xx_write_reg_bits(dev, USBSUSP_REG, start ? 0x10 : 0x00,
 306                                           0x10)) < 0)
 307                 return ret;
 308         /* enable video capture */
 309         return em28xx_write_regs(dev, VINENABLE_REG, start ? "\x67" : "\x27", 1);
 310 }
 311
 312 int em28xx_outfmt_set_yuv422(struct em28xx *dev)
 313 {
 314         em28xx_write_regs(dev, OUTFMT_REG, "\x34", 1);
 315         em28xx_write_regs(dev, VINMODE_REG, "\x10", 1);
 316         return em28xx_write_regs(dev, VINCTRL_REG, "\x11", 1);
 317 }
 318
 319 static int em28xx_accumulator_set(struct em28xx *dev, u8 xmin, u8 xmax,
 320                                   u8 ymin, u8 ymax)
 321 {
 322         em28xx_coredbg("em28xx Scale: (%d,%d)-(%d,%d)\n", xmin, ymin, xmax, ymax);
 323
 324         em28xx_write_regs(dev, XMIN_REG, &xmin, 1);
 325         em28xx_write_regs(dev, XMAX_REG, &xmax, 1);
 326         em28xx_write_regs(dev, YMIN_REG, &ymin, 1);
 327         return em28xx_write_regs(dev, YMAX_REG, &ymax, 1);
 328 }
 329
 330 static int em28xx_capture_area_set(struct em28xx *dev, u8 hstart, u8 vstart,
 331                                    u16 width, u16 height)
 332 {
 333         u8 cwidth = width;
 334         u8 cheight = height;
 335         u8 overflow = (height >> 7 & 0x02) | (width >> 8 & 0x01);
 336
 337         em28xx_coredbg("em28xx Area Set: (%d,%d)\n", (width | (overflow & 2) << 7),
 338                         (height | (overflow & 1) << 8));
 339
 340         em28xx_write_regs(dev, HSTART_REG, &hstart, 1);
 341         em28xx_write_regs(dev, VSTART_REG, &vstart, 1);
 342         em28xx_write_regs(dev, CWIDTH_REG, &cwidth, 1);
 343         em28xx_write_regs(dev, CHEIGHT_REG, &cheight, 1);
 344         return em28xx_write_regs(dev, OFLOW_REG, &overflow, 1);
 345 }
 346
 347 static int em28xx_scaler_set(struct em28xx *dev, u16 h, u16 v)
 348 {
 349         u8 mode;
 350         /* the em2800 scaler only supports scaling down to 50% */
 351         if(dev->is_em2800)
 352                 mode = (v ? 0x20 : 0x00) | (h ? 0x10 : 0x00);
 353         else {
 354                 u8 buf[2];
 355                 buf[0] = h;
 356                 buf[1] = h >> 8;
 357                 em28xx_write_regs(dev, HSCALELOW_REG, (char *)buf, 2);
 358                 buf[0] = v;
 359                 buf[1] = v >> 8;
 360                 em28xx_write_regs(dev, VSCALELOW_REG, (char *)buf, 2);
 361                 /* it seems that both H and V scalers must be active to work correctly */
 362                 mode = (h || v)? 0x30: 0x00;
 363         }
 364         return em28xx_write_reg_bits(dev, COMPR_REG, mode, 0x30);
 365 }
 366
 367 /* FIXME: this only function read values from dev */
 368 int em28xx_resolution_set(struct em28xx *dev)
 369 {
 370         int width, height;
 371         width = norm_maxw(dev);
 372         height = norm_maxh(dev) >> 1;
 373
 374         em28xx_outfmt_set_yuv422(dev);
 375         em28xx_accumulator_set(dev, 1, (width - 4) >> 2, 1, (height - 4) >> 2);
 376         em28xx_capture_area_set(dev, 0, 0, width >> 2, height >> 2);
 377         return em28xx_scaler_set(dev, dev->hscale, dev->vscale);
 378 }
 379
 380
 381 /******************* isoc transfer handling ****************************/
 382
 383 #ifdef ENABLE_DEBUG_ISOC_FRAMES
 384 static void em28xx_isoc_dump(struct urb *urb)
 385 {
 386         int len = 0;
 387         int ntrans = 0;
 388         int i;
 389
 390         printk(KERN_DEBUG "isocIrq: sf=%d np=%d ec=%x\n",
 391                urb->start_frame, urb->number_of_packets,
 392                urb->error_count);
 393         for (i = 0; i < urb->number_of_packets; i++) {
 394                 unsigned char *buf =
 395                                 urb->transfer_buffer +
 396                                 urb->iso_frame_desc[i].offset;
 397                 int alen = urb->iso_frame_desc[i].actual_length;
 398                 if (alen > 0) {
 399                         if (buf[0] == 0x88) {
 400                                 ntrans++;
 401                                 len += alen;
 402                         } else if (buf[0] == 0x22) {
 403                                 printk(KERN_DEBUG
 404                                                 "= l=%d nt=%d bpp=%d\n",
 405                                 len - 4 * ntrans, ntrans,
 406                                 ntrans == 0 ? 0 : len / ntrans);
 407                                 ntrans = 1;
 408                                 len = alen;
 409                         } else
 410                                 printk(KERN_DEBUG "!\n");
 411                 }
 412                 printk(KERN_DEBUG "   n=%d s=%d al=%d %x\n", i,
 413                        urb->iso_frame_desc[i].status,
 414                        urb->iso_frame_desc[i].actual_length,
 415                        (unsigned int)
 416                                        *((unsigned char *)(urb->transfer_buffer +
 417                                        urb->iso_frame_desc[i].
 418                                        offset)));
 419         }
 420 }
 421 #endif
 422
 423 static inline int em28xx_isoc_video(struct em28xx *dev,struct em28xx_frame_t **f,
 424                                     unsigned long *lock_flags, unsigned char buf)
 425 {
 426         if (!(buf & 0x01)) {
 427                 if ((*f)->state == F_GRABBING) {
 428                         /*previous frame is incomplete */
 429                         if ((*f)->fieldbytesused < dev->field_size) {
 430                                 (*f)->state = F_ERROR;
 431                                 em28xx_isocdbg ("dropping incomplete bottom field (%i missing bytes)",
 432                                          dev->field_size-(*f)->fieldbytesused);
 433                         } else {
 434                                 (*f)->state = F_DONE;
 435                                 (*f)->buf.bytesused = dev->frame_size;
 436                         }
 437                 }
 438                 if ((*f)->state == F_DONE || (*f)->state == F_ERROR) {
 439                         /* move current frame to outqueue and get next free buffer from inqueue */
 440                         spin_lock_irqsave(&dev-> queue_lock, *lock_flags);
 441                         list_move_tail(&(*f)->frame, &dev->outqueue);
 442                         if (!list_empty(&dev->inqueue))
 443                                 (*f) = list_entry(dev-> inqueue.next,
 444                         struct em28xx_frame_t,frame);
 445                         else
 446                                 (*f) = NULL;
 447                         spin_unlock_irqrestore(&dev->queue_lock,*lock_flags);
 448                 }
 449                 if (!(*f)) {
 450                         em28xx_isocdbg ("new frame but no buffer is free");
 451                         return -1;
 452                 }
 453                 do_gettimeofday(&(*f)->buf.timestamp);
 454                 (*f)->buf.sequence = ++dev->frame_count;
 455                 (*f)->buf.field = V4L2_FIELD_INTERLACED;
 456                 (*f)->state = F_GRABBING;
 457                 (*f)->buf.bytesused = 0;
 458                 (*f)->top_field = 1;
 459                 (*f)->fieldbytesused = 0;
 460         } else {
 461                                         /* acquiring bottom field */
 462                 if ((*f)->state == F_GRABBING) {
 463                         if (!(*f)->top_field) {
 464                                 (*f)->state = F_ERROR;
 465                                 em28xx_isocdbg ("unexpected begin of bottom field; discarding it");
 466                         } else if ((*f)-> fieldbytesused < dev->field_size - 172) {
 467                                 (*f)->state = F_ERROR;
 468                                 em28xx_isocdbg ("dropping incomplete top field (%i missing bytes)",
 469                                          dev->field_size-(*f)->fieldbytesused);
 470                         } else {
 471                                 (*f)->top_field = 0;
 472                                 (*f)->fieldbytesused = 0;
 473                         }
 474                 }
 475         }
 476         return (0);
 477 }
 478
 479 static inline void em28xx_isoc_video_copy(struct em28xx *dev,
 480                                           struct em28xx_frame_t **f, unsigned char *buf, int len)
 481 {
 482         void *fieldstart, *startwrite, *startread;
 483         int linesdone, currlinedone, offset, lencopy,remain;
 484
 485         if(dev->frame_size != (*f)->buf.length){
 486                 em28xx_err("frame_size %i and buf.length %i are different!!!\n",dev->frame_size,(*f)->buf.length);
 487                 return;
 488         }
 489
 490         if ((*f)->fieldbytesused + len > dev->field_size)
 491                 len =dev->field_size - (*f)->fieldbytesused;
 492
 493         if (buf[0] != 0x88 && buf[0] != 0x22) {
 494                 em28xx_isocdbg("frame is not complete\n");
 495                 startread = buf;
 496                 len+=4;
 497         } else
 498                 startread = buf + 4;
 499
 500         remain = len;
 501
 502         if ((*f)->top_field)
 503                 fieldstart = (*f)->bufmem;
 504         else
 505                 fieldstart = (*f)->bufmem + dev->bytesperline;
 506
 507         linesdone = (*f)->fieldbytesused / dev->bytesperline;
 508         currlinedone = (*f)->fieldbytesused % dev->bytesperline;
 509         offset = linesdone * dev->bytesperline * 2 + currlinedone;
 510         startwrite = fieldstart + offset;
 511         lencopy = dev->bytesperline - currlinedone;
 512         lencopy = lencopy > remain ? remain : lencopy;
 513
 514         memcpy(startwrite, startread, lencopy);
 515         remain -= lencopy;
 516
 517         while (remain > 0) {
 518                 startwrite += lencopy + dev->bytesperline;
 519                 startread += lencopy;
 520                 if (dev->bytesperline > remain)
 521                         lencopy = remain;
 522                 else
 523                         lencopy = dev->bytesperline;
 524
 525                 memcpy(startwrite, startread, lencopy);
 526                 remain -= lencopy;
 527         }
 528
 529         (*f)->fieldbytesused += len;
 530 }
 531
 532 /*
 533  * em28xx_isoIrq()
 534  * handles the incoming isoc urbs and fills the frames from our inqueue
 535  */
 536 static void em28xx_isocIrq(struct urb *urb)
 537 {
 538         struct em28xx *dev = urb->context;
 539         int i, status;
 540         struct em28xx_frame_t **f;
 541         unsigned long lock_flags;
 542
 543         if (!dev)
 544                 return;
 545 #ifdef ENABLE_DEBUG_ISOC_FRAMES
 546         if (isoc_debug>1)
 547                 em28xx_isoc_dump(urb);
 548 #endif
 549
 550         if (urb->status == -ENOENT)
 551                 return;
 552
 553         f = &dev->frame_current;
 554
 555         if (dev->stream == STREAM_INTERRUPT) {
 556                 dev->stream = STREAM_OFF;
 557                 if ((*f))
 558                         (*f)->state = F_QUEUED;
 559                 em28xx_isocdbg("stream interrupted");
 560                 wake_up_interruptible(&dev->wait_stream);
 561         }
 562
 563         if ((dev->state & DEV_DISCONNECTED) || (dev->state & DEV_MISCONFIGURED))
 564                 return;
 565
 566         if (dev->stream == STREAM_ON && !list_empty(&dev->inqueue)) {
 567                 if (!(*f))
 568                         (*f) = list_entry(dev->inqueue.next,
 569                 struct em28xx_frame_t, frame);
 570
 571                 for (i = 0; i < urb->number_of_packets; i++) {
 572                         unsigned char *buf = urb->transfer_buffer +
 573                                         urb->iso_frame_desc[i].offset;
 574                         int len = urb->iso_frame_desc[i].actual_length - 4;
 575
 576                         if (urb->iso_frame_desc[i].status) {
 577                                 em28xx_isocdbg("data error: [%d] len=%d, status=%d", i,
 578                                         urb->iso_frame_desc[i].actual_length,
 579                                         urb->iso_frame_desc[i].status);
 580                                 if (urb->iso_frame_desc[i].status != -EPROTO)
 581                                         continue;
 582                         }
 583                         if (urb->iso_frame_desc[i].actual_length <= 0) {
 584                                 em28xx_isocdbg("packet %d is empty",i);
 585                                 continue;
 586                         }
 587                         if (urb->iso_frame_desc[i].actual_length >
 588                                                  dev->max_pkt_size) {
 589                                 em28xx_isocdbg("packet bigger than packet size");
 590                                 continue;
 591                         }
 592                         /*new frame */
 593                         if (buf[0] == 0x22 && buf[1] == 0x5a) {
 594                                 em28xx_isocdbg("Video frame, length=%i!",len);
 595
 596                                 if (em28xx_isoc_video(dev,f,&lock_flags,buf[2]))
 597                                 break;
 598                         } else if (buf[0]==0x33 && buf[1]==0x95 && buf[2]==0x00) {
 599                                 em28xx_isocdbg("VBI HEADER!!!");
 600                         }
 601
 602                         /* actual copying */
 603                         if ((*f)->state == F_GRABBING) {
 604                                 em28xx_isoc_video_copy(dev,f,buf, len);
 605                         }
 606                 }
 607         }
 608
 609         for (i = 0; i < urb->number_of_packets; i++) {
 610                 urb->iso_frame_desc[i].status = 0;
 611                 urb->iso_frame_desc[i].actual_length = 0;
 612         }
 613
 614         urb->status = 0;
 615         if ((status = usb_submit_urb(urb, GFP_ATOMIC))) {
 616                 em28xx_errdev("resubmit of urb failed (error=%i)\n", status);
 617                 dev->state |= DEV_MISCONFIGURED;
 618         }
 619         wake_up_interruptible(&dev->wait_frame);
 620         return;
 621 }
 622
 623 /*
 624  * em28xx_uninit_isoc()
 625  * deallocates the buffers and urbs allocated during em28xx_init_iosc()
 626  */
 627 void em28xx_uninit_isoc(struct em28xx *dev)
 628 {
 629         int i;
 630
 631         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
 632                 if (dev->urb[i]) {
 633                         usb_kill_urb(dev->urb[i]);
 634                         if (dev->transfer_buffer[i]){
 635                                 usb_buffer_free(dev->udev,(EM28XX_NUM_PACKETS*dev->max_pkt_size),dev->transfer_buffer[i],dev->urb[i]->transfer_dma);
 636                         }
 637                         usb_free_urb(dev->urb[i]);
 638                 }
 639                 dev->urb[i] = NULL;
 640                 dev->transfer_buffer[i] = NULL;
 641         }
 642         em28xx_capture_start(dev, 0);
 643 }
 644
 645 /*
 646  * em28xx_init_isoc()
 647  * allocates transfer buffers and submits the urbs for isoc transfer
 648  */
 649 int em28xx_init_isoc(struct em28xx *dev)
 650 {
 651         /* change interface to 3 which allows the biggest packet sizes */
 652         int i, errCode;
 653         const int sb_size = EM28XX_NUM_PACKETS * dev->max_pkt_size;
 654
 655         /* reset streaming vars */
 656         dev->frame_current = NULL;
 657         dev->frame_count = 0;
 658
 659         /* allocate urbs */
 660         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
 661                 struct urb *urb;
 662                 int j, k;
 663                 /* allocate transfer buffer */
 664                 urb = usb_alloc_urb(EM28XX_NUM_PACKETS, GFP_KERNEL);
 665                 if (!urb){
 666                         em28xx_errdev("cannot alloc urb %i\n", i);
 667                         em28xx_uninit_isoc(dev);
 668                         return -ENOMEM;
 669                 }
 670                 dev->transfer_buffer[i] = usb_buffer_alloc(dev->udev, sb_size, GFP_KERNEL,&urb->transfer_dma);
 671                 if (!dev->transfer_buffer[i]) {
 672                         em28xx_errdev
 673                                         ("unable to allocate %i bytes for transfer buffer %i\n",
 674                                          sb_size, i);
 675                         em28xx_uninit_isoc(dev);
 676                         usb_free_urb(urb);
 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 }