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@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", (unsigned char)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" :
 181                                  "%02x\n", (unsigned char) val);
 182
 183         if (ret < 0)
 184                 return ret;
 185
 186         return val;
 187 }
 188
 189 int em28xx_read_reg(struct em28xx *dev, u16 reg)
 190 {
 191         return em28xx_read_reg_req(dev, USB_REQ_GET_STATUS, reg);
 192 }
 193
 194 /*
 195  * em28xx_write_regs_req()
 196  * sends data to the usb device, specifying bRequest
 197  */
 198 int em28xx_write_regs_req(struct em28xx *dev, u8 req, u16 reg, char *buf,
 199                                  int len)
 200 {
 201         int ret;
 202
 203         /*usb_control_msg seems to expect a kmalloced buffer */
 204         unsigned char *bufs;
 205
 206         if (dev->state & DEV_DISCONNECTED)
 207                 return(-ENODEV);
 208
 209         bufs = kmalloc(len, GFP_KERNEL);
 210
 211         em28xx_regdbg("req=%02x reg=%02x:", req, reg);
 212
 213         if (reg_debug) {
 214                 int i;
 215                 for (i = 0; i < len; ++i)
 216                         printk (" %02x", (unsigned char)buf[i]);
 217                 printk ("\n");
 218         }
 219
 220         if (!bufs)
 221                 return -ENOMEM;
 222         memcpy(bufs, buf, len);
 223         ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0), req,
 224                               USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 225                               0x0000, reg, bufs, len, HZ);
 226         msleep(5);              /* FIXME: magic number */
 227         kfree(bufs);
 228         return ret;
 229 }
 230
 231 int em28xx_write_regs(struct em28xx *dev, u16 reg, char *buf, int len)
 232 {
 233         return em28xx_write_regs_req(dev, USB_REQ_GET_STATUS, reg, buf, len);
 234 }
 235
 236 /*
 237  * em28xx_write_reg_bits()
 238  * sets only some bits (specified by bitmask) of a register, by first reading
 239  * the actual value
 240  */
 241 static int em28xx_write_reg_bits(struct em28xx *dev, u16 reg, u8 val,
 242                                  u8 bitmask)
 243 {
 244         int oldval;
 245         u8 newval;
 246         if ((oldval = em28xx_read_reg(dev, reg)) < 0)
 247                 return oldval;
 248         newval = (((u8) oldval) & ~bitmask) | (val & bitmask);
 249         return em28xx_write_regs(dev, reg, &newval, 1);
 250 }
 251
 252 /*
 253  * em28xx_write_ac97()
 254  * write a 16 bit value to the specified AC97 address (LSB first!)
 255  */
 256 static int em28xx_write_ac97(struct em28xx *dev, u8 reg, u8 *val)
 257 {
 258         int ret, i;
 259         u8 addr = reg & 0x7f;
 260         if ((ret = em28xx_write_regs(dev, AC97LSB_REG, val, 2)) < 0)
 261                 return ret;
 262         if ((ret = em28xx_write_regs(dev, AC97ADDR_REG, &addr, 1)) < 0)
 263                 return ret;
 264
 265         /* Wait up to 50 ms for AC97 command to complete */
 266         for (i = 0; i < 10; i++) {
 267                 if ((ret = em28xx_read_reg(dev, AC97BUSY_REG)) < 0)
 268                         return ret;
 269                 if (!((u8) ret) & 0x01)
 270                         return 0;
 271                 msleep(5);
 272         }
 273         em28xx_warn ("AC97 command still being executed: not handled properly!\n");
 274         return 0;
 275 }
 276
 277 static int em28xx_set_audio_source(struct em28xx *dev)
 278 {
 279         static char *enable  = "\x08\x08";
 280         static char *disable = "\x08\x88";
 281         char *video = enable, *line = disable;
 282         int ret;
 283         u8 input;
 284
 285         if (dev->is_em2800) {
 286                 if (dev->ctl_ainput)
 287                         input = EM2800_AUDIO_SRC_LINE;
 288                 else
 289                         input = EM2800_AUDIO_SRC_TUNER;
 290
 291                 ret = em28xx_write_regs(dev, EM2800_AUDIOSRC_REG, &input, 1);
 292                 if (ret < 0)
 293                         return ret;
 294         }
 295
 296         if (dev->has_msp34xx)
 297                 input = EM28XX_AUDIO_SRC_TUNER;
 298         else {
 299                 switch (dev->ctl_ainput) {
 300                 case EM28XX_AMUX_VIDEO:
 301                         input = EM28XX_AUDIO_SRC_TUNER;
 302                         break;
 303                 case EM28XX_AMUX_LINE_IN:
 304                         input = EM28XX_AUDIO_SRC_LINE;
 305                         break;
 306                 case EM28XX_AMUX_AC97_VIDEO:
 307                         input = EM28XX_AUDIO_SRC_LINE;
 308                         break;
 309                 case EM28XX_AMUX_AC97_LINE_IN:
 310                         input = EM28XX_AUDIO_SRC_LINE;
 311                         video = disable;
 312                         line  = enable;
 313                         break;
 314                 }
 315         }
 316
 317         ret = em28xx_write_reg_bits(dev, AUDIOSRC_REG, input, 0xc0);
 318         if (ret < 0)
 319                 return ret;
 320         msleep(5);
 321
 322         /* Sets AC97 mixer registers
 323            This is seems to be needed, even for non-ac97 configs
 324          */
 325         ret = em28xx_write_ac97(dev, VIDEO_AC97, video);
 326         if (ret < 0)
 327                 return ret;
 328
 329         ret = em28xx_write_ac97(dev, LINE_IN_AC97, line);
 330
 331         return ret;
 332 }
 333
 334 int em28xx_audio_analog_set(struct em28xx *dev)
 335 {
 336         int ret;
 337         char s[2] = { 0x00, 0x00 };
 338         u8 xclk = 0x07;
 339
 340         s[0] |= 0x1f - dev->volume;
 341         s[1] |= 0x1f - dev->volume;
 342
 343         /* Mute */
 344         s[1] |= 0x80;
 345         ret = em28xx_write_ac97(dev, MASTER_AC97, s);
 346
 347         if (ret < 0)
 348                 return ret;
 349
 350         if (dev->has_12mhz_i2s)
 351                 xclk |= 0x20;
 352
 353         if (!dev->mute)
 354                 xclk |= 0x80;
 355
 356         ret = em28xx_write_reg_bits(dev, XCLK_REG, xclk, 0xa7);
 357         if (ret < 0)
 358                 return ret;
 359         msleep(10);
 360
 361         /* Selects the proper audio input */
 362         ret = em28xx_set_audio_source(dev);
 363
 364         /* Unmute device */
 365         if (!dev->mute)
 366                 s[1] &= ~0x80;
 367         ret = em28xx_write_ac97(dev, MASTER_AC97, s);
 368
 369         return ret;
 370 }
 371 EXPORT_SYMBOL_GPL(em28xx_audio_analog_set);
 372
 373 int em28xx_colorlevels_set_default(struct em28xx *dev)
 374 {
 375         em28xx_write_regs(dev, YGAIN_REG, "\x10", 1);   /* contrast */
 376         em28xx_write_regs(dev, YOFFSET_REG, "\x00", 1); /* brightness */
 377         em28xx_write_regs(dev, UVGAIN_REG, "\x10", 1);  /* saturation */
 378         em28xx_write_regs(dev, UOFFSET_REG, "\x00", 1);
 379         em28xx_write_regs(dev, VOFFSET_REG, "\x00", 1);
 380         em28xx_write_regs(dev, SHARPNESS_REG, "\x00", 1);
 381
 382         em28xx_write_regs(dev, GAMMA_REG, "\x20", 1);
 383         em28xx_write_regs(dev, RGAIN_REG, "\x20", 1);
 384         em28xx_write_regs(dev, GGAIN_REG, "\x20", 1);
 385         em28xx_write_regs(dev, BGAIN_REG, "\x20", 1);
 386         em28xx_write_regs(dev, ROFFSET_REG, "\x00", 1);
 387         em28xx_write_regs(dev, GOFFSET_REG, "\x00", 1);
 388         return em28xx_write_regs(dev, BOFFSET_REG, "\x00", 1);
 389 }
 390
 391 int em28xx_capture_start(struct em28xx *dev, int start)
 392 {
 393         int ret;
 394         /* FIXME: which is the best order? */
 395         /* video registers are sampled by VREF */
 396         if ((ret = em28xx_write_reg_bits(dev, USBSUSP_REG, start ? 0x10 : 0x00,
 397                                           0x10)) < 0)
 398                 return ret;
 399         /* enable video capture */
 400         return em28xx_write_regs(dev, VINENABLE_REG, start ? "\x67" : "\x27", 1);
 401 }
 402
 403 int em28xx_outfmt_set_yuv422(struct em28xx *dev)
 404 {
 405         em28xx_write_regs(dev, OUTFMT_REG, "\x34", 1);
 406         em28xx_write_regs(dev, VINMODE_REG, "\x10", 1);
 407         return em28xx_write_regs(dev, VINCTRL_REG, "\x11", 1);
 408 }
 409
 410 static int em28xx_accumulator_set(struct em28xx *dev, u8 xmin, u8 xmax,
 411                                   u8 ymin, u8 ymax)
 412 {
 413         em28xx_coredbg("em28xx Scale: (%d,%d)-(%d,%d)\n", xmin, ymin, xmax, ymax);
 414
 415         em28xx_write_regs(dev, XMIN_REG, &xmin, 1);
 416         em28xx_write_regs(dev, XMAX_REG, &xmax, 1);
 417         em28xx_write_regs(dev, YMIN_REG, &ymin, 1);
 418         return em28xx_write_regs(dev, YMAX_REG, &ymax, 1);
 419 }
 420
 421 static int em28xx_capture_area_set(struct em28xx *dev, u8 hstart, u8 vstart,
 422                                    u16 width, u16 height)
 423 {
 424         u8 cwidth = width;
 425         u8 cheight = height;
 426         u8 overflow = (height >> 7 & 0x02) | (width >> 8 & 0x01);
 427
 428         em28xx_coredbg("em28xx Area Set: (%d,%d)\n", (width | (overflow & 2) << 7),
 429                         (height | (overflow & 1) << 8));
 430
 431         em28xx_write_regs(dev, HSTART_REG, &hstart, 1);
 432         em28xx_write_regs(dev, VSTART_REG, &vstart, 1);
 433         em28xx_write_regs(dev, CWIDTH_REG, &cwidth, 1);
 434         em28xx_write_regs(dev, CHEIGHT_REG, &cheight, 1);
 435         return em28xx_write_regs(dev, OFLOW_REG, &overflow, 1);
 436 }
 437
 438 static int em28xx_scaler_set(struct em28xx *dev, u16 h, u16 v)
 439 {
 440         u8 mode;
 441         /* the em2800 scaler only supports scaling down to 50% */
 442         if(dev->is_em2800)
 443                 mode = (v ? 0x20 : 0x00) | (h ? 0x10 : 0x00);
 444         else {
 445                 u8 buf[2];
 446                 buf[0] = h;
 447                 buf[1] = h >> 8;
 448                 em28xx_write_regs(dev, HSCALELOW_REG, (char *)buf, 2);
 449                 buf[0] = v;
 450                 buf[1] = v >> 8;
 451                 em28xx_write_regs(dev, VSCALELOW_REG, (char *)buf, 2);
 452                 /* it seems that both H and V scalers must be active to work correctly */
 453                 mode = (h || v)? 0x30: 0x00;
 454         }
 455         return em28xx_write_reg_bits(dev, COMPR_REG, mode, 0x30);
 456 }
 457
 458 /* FIXME: this only function read values from dev */
 459 int em28xx_resolution_set(struct em28xx *dev)
 460 {
 461         int width, height;
 462         width = norm_maxw(dev);
 463         height = norm_maxh(dev) >> 1;
 464
 465         em28xx_outfmt_set_yuv422(dev);
 466         em28xx_accumulator_set(dev, 1, (width - 4) >> 2, 1, (height - 4) >> 2);
 467         em28xx_capture_area_set(dev, 0, 0, width >> 2, height >> 2);
 468         return em28xx_scaler_set(dev, dev->hscale, dev->vscale);
 469 }
 470
 471
 472 /******************* isoc transfer handling ****************************/
 473
 474 #ifdef ENABLE_DEBUG_ISOC_FRAMES
 475 static void em28xx_isoc_dump(struct urb *urb)
 476 {
 477         int len = 0;
 478         int ntrans = 0;
 479         int i;
 480
 481         printk(KERN_DEBUG "isocIrq: sf=%d np=%d ec=%x\n",
 482                urb->start_frame, urb->number_of_packets,
 483                urb->error_count);
 484         for (i = 0; i < urb->number_of_packets; i++) {
 485                 unsigned char *buf =
 486                                 urb->transfer_buffer +
 487                                 urb->iso_frame_desc[i].offset;
 488                 int alen = urb->iso_frame_desc[i].actual_length;
 489                 if (alen > 0) {
 490                         if (buf[0] == 0x88) {
 491                                 ntrans++;
 492                                 len += alen;
 493                         } else if (buf[0] == 0x22) {
 494                                 printk(KERN_DEBUG
 495                                                 "= l=%d nt=%d bpp=%d\n",
 496                                 len - 4 * ntrans, ntrans,
 497                                 ntrans == 0 ? 0 : len / ntrans);
 498                                 ntrans = 1;
 499                                 len = alen;
 500                         } else
 501                                 printk(KERN_DEBUG "!\n");
 502                 }
 503                 printk(KERN_DEBUG "   n=%d s=%d al=%d %x\n", i,
 504                        urb->iso_frame_desc[i].status,
 505                        urb->iso_frame_desc[i].actual_length,
 506                        (unsigned int)
 507                                        *((unsigned char *)(urb->transfer_buffer +
 508                                        urb->iso_frame_desc[i].
 509                                        offset)));
 510         }
 511 }
 512 #endif
 513
 514 static inline int em28xx_isoc_video(struct em28xx *dev,struct em28xx_frame_t **f,
 515                                     unsigned long *lock_flags, unsigned char buf)
 516 {
 517         if (!(buf & 0x01)) {
 518                 if ((*f)->state == F_GRABBING) {
 519                         /*previous frame is incomplete */
 520                         if ((*f)->fieldbytesused < dev->field_size) {
 521                                 (*f)->state = F_ERROR;
 522                                 em28xx_isocdbg ("dropping incomplete bottom field (%i missing bytes)",
 523                                          dev->field_size-(*f)->fieldbytesused);
 524                         } else {
 525                                 (*f)->state = F_DONE;
 526                                 (*f)->buf.bytesused = dev->frame_size;
 527                         }
 528                 }
 529                 if ((*f)->state == F_DONE || (*f)->state == F_ERROR) {
 530                         /* move current frame to outqueue and get next free buffer from inqueue */
 531                         spin_lock_irqsave(&dev-> queue_lock, *lock_flags);
 532                         list_move_tail(&(*f)->frame, &dev->outqueue);
 533                         if (!list_empty(&dev->inqueue))
 534                                 (*f) = list_entry(dev-> inqueue.next,
 535                         struct em28xx_frame_t,frame);
 536                         else
 537                                 (*f) = NULL;
 538                         spin_unlock_irqrestore(&dev->queue_lock,*lock_flags);
 539                 }
 540                 if (!(*f)) {
 541                         em28xx_isocdbg ("new frame but no buffer is free");
 542                         return -1;
 543                 }
 544                 do_gettimeofday(&(*f)->buf.timestamp);
 545                 (*f)->buf.sequence = ++dev->frame_count;
 546                 (*f)->buf.field = V4L2_FIELD_INTERLACED;
 547                 (*f)->state = F_GRABBING;
 548                 (*f)->buf.bytesused = 0;
 549                 (*f)->top_field = 1;
 550                 (*f)->fieldbytesused = 0;
 551         } else {
 552                                         /* acquiring bottom field */
 553                 if ((*f)->state == F_GRABBING) {
 554                         if (!(*f)->top_field) {
 555                                 (*f)->state = F_ERROR;
 556                                 em28xx_isocdbg ("unexpected begin of bottom field; discarding it");
 557                         } else if ((*f)-> fieldbytesused < dev->field_size - 172) {
 558                                 (*f)->state = F_ERROR;
 559                                 em28xx_isocdbg ("dropping incomplete top field (%i missing bytes)",
 560                                          dev->field_size-(*f)->fieldbytesused);
 561                         } else {
 562                                 (*f)->top_field = 0;
 563                                 (*f)->fieldbytesused = 0;
 564                         }
 565                 }
 566         }
 567         return (0);
 568 }
 569
 570 static inline void em28xx_isoc_video_copy(struct em28xx *dev,
 571                                           struct em28xx_frame_t **f, unsigned char *buf, int len)
 572 {
 573         void *fieldstart, *startwrite, *startread;
 574         int linesdone, currlinedone, offset, lencopy,remain;
 575
 576         if(dev->frame_size != (*f)->buf.length){
 577                 em28xx_err("frame_size %i and buf.length %i are different!!!\n",dev->frame_size,(*f)->buf.length);
 578                 return;
 579         }
 580
 581         if ((*f)->fieldbytesused + len > dev->field_size)
 582                 len =dev->field_size - (*f)->fieldbytesused;
 583
 584         if (buf[0] != 0x88 && buf[0] != 0x22) {
 585                 em28xx_isocdbg("frame is not complete\n");
 586                 startread = buf;
 587                 len+=4;
 588         } else
 589                 startread = buf + 4;
 590
 591         remain = len;
 592
 593         if ((*f)->top_field)
 594                 fieldstart = (*f)->bufmem;
 595         else
 596                 fieldstart = (*f)->bufmem + dev->bytesperline;
 597
 598         linesdone = (*f)->fieldbytesused / dev->bytesperline;
 599         currlinedone = (*f)->fieldbytesused % dev->bytesperline;
 600         offset = linesdone * dev->bytesperline * 2 + currlinedone;
 601         startwrite = fieldstart + offset;
 602         lencopy = dev->bytesperline - currlinedone;
 603         lencopy = lencopy > remain ? remain : lencopy;
 604
 605         memcpy(startwrite, startread, lencopy);
 606         remain -= lencopy;
 607
 608         while (remain > 0) {
 609                 startwrite += lencopy + dev->bytesperline;
 610                 startread += lencopy;
 611                 if (dev->bytesperline > remain)
 612                         lencopy = remain;
 613                 else
 614                         lencopy = dev->bytesperline;
 615
 616                 memcpy(startwrite, startread, lencopy);
 617                 remain -= lencopy;
 618         }
 619
 620         (*f)->fieldbytesused += len;
 621 }
 622
 623 /*
 624  * em28xx_isoIrq()
 625  * handles the incoming isoc urbs and fills the frames from our inqueue
 626  */
 627 static void em28xx_isocIrq(struct urb *urb)
 628 {
 629         struct em28xx *dev = urb->context;
 630         int i, status;
 631         struct em28xx_frame_t **f;
 632         unsigned long lock_flags;
 633
 634         if (!dev)
 635                 return;
 636 #ifdef ENABLE_DEBUG_ISOC_FRAMES
 637         if (isoc_debug>1)
 638                 em28xx_isoc_dump(urb);
 639 #endif
 640
 641         if (urb->status == -ENOENT)
 642                 return;
 643
 644         f = &dev->frame_current;
 645
 646         if (dev->stream == STREAM_INTERRUPT) {
 647                 dev->stream = STREAM_OFF;
 648                 if ((*f))
 649                         (*f)->state = F_QUEUED;
 650                 em28xx_isocdbg("stream interrupted");
 651                 wake_up_interruptible(&dev->wait_stream);
 652         }
 653
 654         if ((dev->state & DEV_DISCONNECTED) || (dev->state & DEV_MISCONFIGURED))
 655                 return;
 656
 657         if (dev->stream == STREAM_ON && !list_empty(&dev->inqueue)) {
 658                 if (!(*f))
 659                         (*f) = list_entry(dev->inqueue.next,
 660                 struct em28xx_frame_t, frame);
 661
 662                 for (i = 0; i < urb->number_of_packets; i++) {
 663                         unsigned char *buf = urb->transfer_buffer +
 664                                         urb->iso_frame_desc[i].offset;
 665                         int len = urb->iso_frame_desc[i].actual_length - 4;
 666
 667                         if (urb->iso_frame_desc[i].status) {
 668                                 em28xx_isocdbg("data error: [%d] len=%d, status=%d", i,
 669                                         urb->iso_frame_desc[i].actual_length,
 670                                         urb->iso_frame_desc[i].status);
 671                                 if (urb->iso_frame_desc[i].status != -EPROTO)
 672                                         continue;
 673                         }
 674                         if (urb->iso_frame_desc[i].actual_length <= 0) {
 675                                 em28xx_isocdbg("packet %d is empty",i);
 676                                 continue;
 677                         }
 678                         if (urb->iso_frame_desc[i].actual_length >
 679                                                  dev->max_pkt_size) {
 680                                 em28xx_isocdbg("packet bigger than packet size");
 681                                 continue;
 682                         }
 683                         /*new frame */
 684                         if (buf[0] == 0x22 && buf[1] == 0x5a) {
 685                                 em28xx_isocdbg("Video frame, length=%i!",len);
 686
 687                                 if (em28xx_isoc_video(dev,f,&lock_flags,buf[2]))
 688                                 break;
 689                         } else if (buf[0]==0x33 && buf[1]==0x95 && buf[2]==0x00) {
 690                                 em28xx_isocdbg("VBI HEADER!!!");
 691                         }
 692
 693                         /* actual copying */
 694                         if ((*f)->state == F_GRABBING) {
 695                                 em28xx_isoc_video_copy(dev,f,buf, len);
 696                         }
 697                 }
 698         }
 699
 700         for (i = 0; i < urb->number_of_packets; i++) {
 701                 urb->iso_frame_desc[i].status = 0;
 702                 urb->iso_frame_desc[i].actual_length = 0;
 703         }
 704
 705         urb->status = 0;
 706         if ((status = usb_submit_urb(urb, GFP_ATOMIC))) {
 707                 em28xx_errdev("resubmit of urb failed (error=%i)\n", status);
 708                 dev->state |= DEV_MISCONFIGURED;
 709         }
 710         wake_up_interruptible(&dev->wait_frame);
 711         return;
 712 }
 713
 714 /*
 715  * em28xx_uninit_isoc()
 716  * deallocates the buffers and urbs allocated during em28xx_init_iosc()
 717  */
 718 void em28xx_uninit_isoc(struct em28xx *dev)
 719 {
 720         int i;
 721
 722         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
 723                 if (dev->urb[i]) {
 724                         usb_kill_urb(dev->urb[i]);
 725                         if (dev->transfer_buffer[i]){
 726                                 usb_buffer_free(dev->udev,(EM28XX_NUM_PACKETS*dev->max_pkt_size),dev->transfer_buffer[i],dev->urb[i]->transfer_dma);
 727                         }
 728                         usb_free_urb(dev->urb[i]);
 729                 }
 730                 dev->urb[i] = NULL;
 731                 dev->transfer_buffer[i] = NULL;
 732         }
 733         em28xx_capture_start(dev, 0);
 734 }
 735
 736 /*
 737  * em28xx_init_isoc()
 738  * allocates transfer buffers and submits the urbs for isoc transfer
 739  */
 740 int em28xx_init_isoc(struct em28xx *dev)
 741 {
 742         /* change interface to 3 which allows the biggest packet sizes */
 743         int i, errCode;
 744         const int sb_size = EM28XX_NUM_PACKETS * dev->max_pkt_size;
 745
 746         /* reset streaming vars */
 747         dev->frame_current = NULL;
 748         dev->frame_count = 0;
 749
 750         /* allocate urbs */
 751         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
 752                 struct urb *urb;
 753                 int j, k;
 754                 /* allocate transfer buffer */
 755                 urb = usb_alloc_urb(EM28XX_NUM_PACKETS, GFP_KERNEL);
 756                 if (!urb){
 757                         em28xx_errdev("cannot alloc urb %i\n", i);
 758                         em28xx_uninit_isoc(dev);
 759                         return -ENOMEM;
 760                 }
 761                 dev->transfer_buffer[i] = usb_buffer_alloc(dev->udev, sb_size, GFP_KERNEL,&urb->transfer_dma);
 762                 if (!dev->transfer_buffer[i]) {
 763                         em28xx_errdev
 764                                         ("unable to allocate %i bytes for transfer buffer %i\n",
 765                                          sb_size, i);
 766                         em28xx_uninit_isoc(dev);
 767                         usb_free_urb(urb);
 768                         return -ENOMEM;
 769                 }
 770                 memset(dev->transfer_buffer[i], 0, sb_size);
 771                 urb->dev = dev->udev;
 772                 urb->context = dev;
 773                 urb->pipe = usb_rcvisocpipe(dev->udev, 0x82);
 774                 urb->transfer_flags = URB_ISO_ASAP;
 775                 urb->interval = 1;
 776                 urb->transfer_buffer = dev->transfer_buffer[i];
 777                 urb->complete = em28xx_isocIrq;
 778                 urb->number_of_packets = EM28XX_NUM_PACKETS;
 779                 urb->transfer_buffer_length = sb_size;
 780                 for (j = k = 0; j < EM28XX_NUM_PACKETS;
 781                                 j++, k += dev->max_pkt_size) {
 782                         urb->iso_frame_desc[j].offset = k;
 783                         urb->iso_frame_desc[j].length =
 784                                 dev->max_pkt_size;
 785                 }
 786                 dev->urb[i] = urb;
 787         }
 788
 789         /* submit urbs */
 790         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
 791                 errCode = usb_submit_urb(dev->urb[i], GFP_KERNEL);
 792                 if (errCode) {
 793                         em28xx_errdev("submit of urb %i failed (error=%i)\n", i,
 794                                       errCode);
 795                         em28xx_uninit_isoc(dev);
 796                         return errCode;
 797                 }
 798         }
 799
 800         return 0;
 801 }
 802
 803 int em28xx_set_alternate(struct em28xx *dev)
 804 {
 805         int errCode, prev_alt = dev->alt;
 806         dev->alt = alt;
 807         if (dev->alt == 0) {
 808                 int i;
 809                 for(i=0;i< dev->num_alt; i++)
 810                         if(dev->alt_max_pkt_size[i]>dev->alt_max_pkt_size[dev->alt])
 811                                 dev->alt=i;
 812         }
 813
 814         if (dev->alt != prev_alt) {
 815                 dev->max_pkt_size = dev->alt_max_pkt_size[dev->alt];
 816                 em28xx_coredbg("setting alternate %d with wMaxPacketSize=%u\n", dev->alt,
 817                        dev->max_pkt_size);
 818                 errCode = usb_set_interface(dev->udev, 0, dev->alt);
 819                 if (errCode < 0) {
 820                         em28xx_errdev ("cannot change alternate number to %d (error=%i)\n",
 821                                                         dev->alt, errCode);
 822                         return errCode;
 823                 }
 824         }
 825         return 0;
 826 }