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 static 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_set_audio_source(struct em28xx *dev)
 272 {
 273         static char *enable  = "\x08\x08";
 274         static char *disable = "\x08\x88";
 275         char *video = enable, *line = disable;
 276         int ret, no_ac97;
 277         u8 input;
 278
 279         if (dev->is_em2800) {
 280                 if (dev->ctl_ainput)
 281                         input = EM2800_AUDIO_SRC_LINE;
 282                 else
 283                         input = EM2800_AUDIO_SRC_TUNER;
 284
 285                 ret = em28xx_write_regs(dev, EM2800_AUDIOSRC_REG, &input, 1);
 286                 if (ret < 0)
 287                         return ret;
 288         }
 289
 290         if (dev->has_msp34xx)
 291                 input = EM28XX_AUDIO_SRC_TUNER;
 292         else {
 293                 switch (dev->ctl_ainput) {
 294                 case EM28XX_AMUX_VIDEO:
 295                         input = EM28XX_AUDIO_SRC_TUNER;
 296                         no_ac97 = 1;
 297                         break;
 298                 case EM28XX_AMUX_LINE_IN:
 299                         input = EM28XX_AUDIO_SRC_LINE;
 300                         no_ac97 = 1;
 301                         break;
 302                 case EM28XX_AMUX_AC97_VIDEO:
 303                         input = EM28XX_AUDIO_SRC_LINE;
 304                         break;
 305                 case EM28XX_AMUX_AC97_LINE_IN:
 306                         input = EM28XX_AUDIO_SRC_LINE;
 307                         video = disable;
 308                         line  = enable;
 309                         break;
 310                 }
 311         }
 312
 313         ret = em28xx_write_reg_bits(dev, AUDIOSRC_REG, input, 0xc0);
 314         if (ret < 0)
 315                 return ret;
 316
 317         if (no_ac97)
 318                 return 0;
 319
 320         /* Sets AC97 mixer registers */
 321
 322         ret = em28xx_write_ac97(dev, VIDEO_AC97, video);
 323         if (ret < 0)
 324                 return ret;
 325
 326         ret = em28xx_write_ac97(dev, LINE_IN_AC97, line);
 327
 328         return ret;
 329 }
 330
 331 int em28xx_audio_analog_set(struct em28xx *dev)
 332 {
 333         int ret;
 334         char s[2] = { 0x00, 0x00 };
 335
 336         s[0] |= 0x1f - dev->volume;
 337         s[1] |= 0x1f - dev->volume;
 338
 339         if (dev->mute)
 340                 s[1] |= 0x80;
 341         ret = em28xx_write_ac97(dev, MASTER_AC97, s);
 342         if (ret < 0)
 343                 return ret;
 344
 345         ret = em28xx_write_reg_bits(dev, XCLK_REG,
 346                                     dev->mute ? 0x00 : 0x80, 0x80);
 347         if (ret < 0)
 348                 return ret;
 349
 350         /* Selects the proper audio input */
 351         ret = em28xx_set_audio_source(dev);
 352
 353         return ret;
 354 }
 355 EXPORT_SYMBOL_GPL(em28xx_audio_analog_set);
 356
 357 int em28xx_colorlevels_set_default(struct em28xx *dev)
 358 {
 359         em28xx_write_regs(dev, YGAIN_REG, "\x10", 1);   /* contrast */
 360         em28xx_write_regs(dev, YOFFSET_REG, "\x00", 1); /* brightness */
 361         em28xx_write_regs(dev, UVGAIN_REG, "\x10", 1);  /* saturation */
 362         em28xx_write_regs(dev, UOFFSET_REG, "\x00", 1);
 363         em28xx_write_regs(dev, VOFFSET_REG, "\x00", 1);
 364         em28xx_write_regs(dev, SHARPNESS_REG, "\x00", 1);
 365
 366         em28xx_write_regs(dev, GAMMA_REG, "\x20", 1);
 367         em28xx_write_regs(dev, RGAIN_REG, "\x20", 1);
 368         em28xx_write_regs(dev, GGAIN_REG, "\x20", 1);
 369         em28xx_write_regs(dev, BGAIN_REG, "\x20", 1);
 370         em28xx_write_regs(dev, ROFFSET_REG, "\x00", 1);
 371         em28xx_write_regs(dev, GOFFSET_REG, "\x00", 1);
 372         return em28xx_write_regs(dev, BOFFSET_REG, "\x00", 1);
 373 }
 374
 375 int em28xx_capture_start(struct em28xx *dev, int start)
 376 {
 377         int ret;
 378         /* FIXME: which is the best order? */
 379         /* video registers are sampled by VREF */
 380         if ((ret = em28xx_write_reg_bits(dev, USBSUSP_REG, start ? 0x10 : 0x00,
 381                                           0x10)) < 0)
 382                 return ret;
 383         /* enable video capture */
 384         return em28xx_write_regs(dev, VINENABLE_REG, start ? "\x67" : "\x27", 1);
 385 }
 386
 387 int em28xx_outfmt_set_yuv422(struct em28xx *dev)
 388 {
 389         em28xx_write_regs(dev, OUTFMT_REG, "\x34", 1);
 390         em28xx_write_regs(dev, VINMODE_REG, "\x10", 1);
 391         return em28xx_write_regs(dev, VINCTRL_REG, "\x11", 1);
 392 }
 393
 394 static int em28xx_accumulator_set(struct em28xx *dev, u8 xmin, u8 xmax,
 395                                   u8 ymin, u8 ymax)
 396 {
 397         em28xx_coredbg("em28xx Scale: (%d,%d)-(%d,%d)\n", xmin, ymin, xmax, ymax);
 398
 399         em28xx_write_regs(dev, XMIN_REG, &xmin, 1);
 400         em28xx_write_regs(dev, XMAX_REG, &xmax, 1);
 401         em28xx_write_regs(dev, YMIN_REG, &ymin, 1);
 402         return em28xx_write_regs(dev, YMAX_REG, &ymax, 1);
 403 }
 404
 405 static int em28xx_capture_area_set(struct em28xx *dev, u8 hstart, u8 vstart,
 406                                    u16 width, u16 height)
 407 {
 408         u8 cwidth = width;
 409         u8 cheight = height;
 410         u8 overflow = (height >> 7 & 0x02) | (width >> 8 & 0x01);
 411
 412         em28xx_coredbg("em28xx Area Set: (%d,%d)\n", (width | (overflow & 2) << 7),
 413                         (height | (overflow & 1) << 8));
 414
 415         em28xx_write_regs(dev, HSTART_REG, &hstart, 1);
 416         em28xx_write_regs(dev, VSTART_REG, &vstart, 1);
 417         em28xx_write_regs(dev, CWIDTH_REG, &cwidth, 1);
 418         em28xx_write_regs(dev, CHEIGHT_REG, &cheight, 1);
 419         return em28xx_write_regs(dev, OFLOW_REG, &overflow, 1);
 420 }
 421
 422 static int em28xx_scaler_set(struct em28xx *dev, u16 h, u16 v)
 423 {
 424         u8 mode;
 425         /* the em2800 scaler only supports scaling down to 50% */
 426         if(dev->is_em2800)
 427                 mode = (v ? 0x20 : 0x00) | (h ? 0x10 : 0x00);
 428         else {
 429                 u8 buf[2];
 430                 buf[0] = h;
 431                 buf[1] = h >> 8;
 432                 em28xx_write_regs(dev, HSCALELOW_REG, (char *)buf, 2);
 433                 buf[0] = v;
 434                 buf[1] = v >> 8;
 435                 em28xx_write_regs(dev, VSCALELOW_REG, (char *)buf, 2);
 436                 /* it seems that both H and V scalers must be active to work correctly */
 437                 mode = (h || v)? 0x30: 0x00;
 438         }
 439         return em28xx_write_reg_bits(dev, COMPR_REG, mode, 0x30);
 440 }
 441
 442 /* FIXME: this only function read values from dev */
 443 int em28xx_resolution_set(struct em28xx *dev)
 444 {
 445         int width, height;
 446         width = norm_maxw(dev);
 447         height = norm_maxh(dev) >> 1;
 448
 449         em28xx_outfmt_set_yuv422(dev);
 450         em28xx_accumulator_set(dev, 1, (width - 4) >> 2, 1, (height - 4) >> 2);
 451         em28xx_capture_area_set(dev, 0, 0, width >> 2, height >> 2);
 452         return em28xx_scaler_set(dev, dev->hscale, dev->vscale);
 453 }
 454
 455
 456 /******************* isoc transfer handling ****************************/
 457
 458 #ifdef ENABLE_DEBUG_ISOC_FRAMES
 459 static void em28xx_isoc_dump(struct urb *urb)
 460 {
 461         int len = 0;
 462         int ntrans = 0;
 463         int i;
 464
 465         printk(KERN_DEBUG "isocIrq: sf=%d np=%d ec=%x\n",
 466                urb->start_frame, urb->number_of_packets,
 467                urb->error_count);
 468         for (i = 0; i < urb->number_of_packets; i++) {
 469                 unsigned char *buf =
 470                                 urb->transfer_buffer +
 471                                 urb->iso_frame_desc[i].offset;
 472                 int alen = urb->iso_frame_desc[i].actual_length;
 473                 if (alen > 0) {
 474                         if (buf[0] == 0x88) {
 475                                 ntrans++;
 476                                 len += alen;
 477                         } else if (buf[0] == 0x22) {
 478                                 printk(KERN_DEBUG
 479                                                 "= l=%d nt=%d bpp=%d\n",
 480                                 len - 4 * ntrans, ntrans,
 481                                 ntrans == 0 ? 0 : len / ntrans);
 482                                 ntrans = 1;
 483                                 len = alen;
 484                         } else
 485                                 printk(KERN_DEBUG "!\n");
 486                 }
 487                 printk(KERN_DEBUG "   n=%d s=%d al=%d %x\n", i,
 488                        urb->iso_frame_desc[i].status,
 489                        urb->iso_frame_desc[i].actual_length,
 490                        (unsigned int)
 491                                        *((unsigned char *)(urb->transfer_buffer +
 492                                        urb->iso_frame_desc[i].
 493                                        offset)));
 494         }
 495 }
 496 #endif
 497
 498 static inline int em28xx_isoc_video(struct em28xx *dev,struct em28xx_frame_t **f,
 499                                     unsigned long *lock_flags, unsigned char buf)
 500 {
 501         if (!(buf & 0x01)) {
 502                 if ((*f)->state == F_GRABBING) {
 503                         /*previous frame is incomplete */
 504                         if ((*f)->fieldbytesused < dev->field_size) {
 505                                 (*f)->state = F_ERROR;
 506                                 em28xx_isocdbg ("dropping incomplete bottom field (%i missing bytes)",
 507                                          dev->field_size-(*f)->fieldbytesused);
 508                         } else {
 509                                 (*f)->state = F_DONE;
 510                                 (*f)->buf.bytesused = dev->frame_size;
 511                         }
 512                 }
 513                 if ((*f)->state == F_DONE || (*f)->state == F_ERROR) {
 514                         /* move current frame to outqueue and get next free buffer from inqueue */
 515                         spin_lock_irqsave(&dev-> queue_lock, *lock_flags);
 516                         list_move_tail(&(*f)->frame, &dev->outqueue);
 517                         if (!list_empty(&dev->inqueue))
 518                                 (*f) = list_entry(dev-> inqueue.next,
 519                         struct em28xx_frame_t,frame);
 520                         else
 521                                 (*f) = NULL;
 522                         spin_unlock_irqrestore(&dev->queue_lock,*lock_flags);
 523                 }
 524                 if (!(*f)) {
 525                         em28xx_isocdbg ("new frame but no buffer is free");
 526                         return -1;
 527                 }
 528                 do_gettimeofday(&(*f)->buf.timestamp);
 529                 (*f)->buf.sequence = ++dev->frame_count;
 530                 (*f)->buf.field = V4L2_FIELD_INTERLACED;
 531                 (*f)->state = F_GRABBING;
 532                 (*f)->buf.bytesused = 0;
 533                 (*f)->top_field = 1;
 534                 (*f)->fieldbytesused = 0;
 535         } else {
 536                                         /* acquiring bottom field */
 537                 if ((*f)->state == F_GRABBING) {
 538                         if (!(*f)->top_field) {
 539                                 (*f)->state = F_ERROR;
 540                                 em28xx_isocdbg ("unexpected begin of bottom field; discarding it");
 541                         } else if ((*f)-> fieldbytesused < dev->field_size - 172) {
 542                                 (*f)->state = F_ERROR;
 543                                 em28xx_isocdbg ("dropping incomplete top field (%i missing bytes)",
 544                                          dev->field_size-(*f)->fieldbytesused);
 545                         } else {
 546                                 (*f)->top_field = 0;
 547                                 (*f)->fieldbytesused = 0;
 548                         }
 549                 }
 550         }
 551         return (0);
 552 }
 553
 554 static inline void em28xx_isoc_video_copy(struct em28xx *dev,
 555                                           struct em28xx_frame_t **f, unsigned char *buf, int len)
 556 {
 557         void *fieldstart, *startwrite, *startread;
 558         int linesdone, currlinedone, offset, lencopy,remain;
 559
 560         if(dev->frame_size != (*f)->buf.length){
 561                 em28xx_err("frame_size %i and buf.length %i are different!!!\n",dev->frame_size,(*f)->buf.length);
 562                 return;
 563         }
 564
 565         if ((*f)->fieldbytesused + len > dev->field_size)
 566                 len =dev->field_size - (*f)->fieldbytesused;
 567
 568         if (buf[0] != 0x88 && buf[0] != 0x22) {
 569                 em28xx_isocdbg("frame is not complete\n");
 570                 startread = buf;
 571                 len+=4;
 572         } else
 573                 startread = buf + 4;
 574
 575         remain = len;
 576
 577         if ((*f)->top_field)
 578                 fieldstart = (*f)->bufmem;
 579         else
 580                 fieldstart = (*f)->bufmem + dev->bytesperline;
 581
 582         linesdone = (*f)->fieldbytesused / dev->bytesperline;
 583         currlinedone = (*f)->fieldbytesused % dev->bytesperline;
 584         offset = linesdone * dev->bytesperline * 2 + currlinedone;
 585         startwrite = fieldstart + offset;
 586         lencopy = dev->bytesperline - currlinedone;
 587         lencopy = lencopy > remain ? remain : lencopy;
 588
 589         memcpy(startwrite, startread, lencopy);
 590         remain -= lencopy;
 591
 592         while (remain > 0) {
 593                 startwrite += lencopy + dev->bytesperline;
 594                 startread += lencopy;
 595                 if (dev->bytesperline > remain)
 596                         lencopy = remain;
 597                 else
 598                         lencopy = dev->bytesperline;
 599
 600                 memcpy(startwrite, startread, lencopy);
 601                 remain -= lencopy;
 602         }
 603
 604         (*f)->fieldbytesused += len;
 605 }
 606
 607 /*
 608  * em28xx_isoIrq()
 609  * handles the incoming isoc urbs and fills the frames from our inqueue
 610  */
 611 static void em28xx_isocIrq(struct urb *urb)
 612 {
 613         struct em28xx *dev = urb->context;
 614         int i, status;
 615         struct em28xx_frame_t **f;
 616         unsigned long lock_flags;
 617
 618         if (!dev)
 619                 return;
 620 #ifdef ENABLE_DEBUG_ISOC_FRAMES
 621         if (isoc_debug>1)
 622                 em28xx_isoc_dump(urb);
 623 #endif
 624
 625         if (urb->status == -ENOENT)
 626                 return;
 627
 628         f = &dev->frame_current;
 629
 630         if (dev->stream == STREAM_INTERRUPT) {
 631                 dev->stream = STREAM_OFF;
 632                 if ((*f))
 633                         (*f)->state = F_QUEUED;
 634                 em28xx_isocdbg("stream interrupted");
 635                 wake_up_interruptible(&dev->wait_stream);
 636         }
 637
 638         if ((dev->state & DEV_DISCONNECTED) || (dev->state & DEV_MISCONFIGURED))
 639                 return;
 640
 641         if (dev->stream == STREAM_ON && !list_empty(&dev->inqueue)) {
 642                 if (!(*f))
 643                         (*f) = list_entry(dev->inqueue.next,
 644                 struct em28xx_frame_t, frame);
 645
 646                 for (i = 0; i < urb->number_of_packets; i++) {
 647                         unsigned char *buf = urb->transfer_buffer +
 648                                         urb->iso_frame_desc[i].offset;
 649                         int len = urb->iso_frame_desc[i].actual_length - 4;
 650
 651                         if (urb->iso_frame_desc[i].status) {
 652                                 em28xx_isocdbg("data error: [%d] len=%d, status=%d", i,
 653                                         urb->iso_frame_desc[i].actual_length,
 654                                         urb->iso_frame_desc[i].status);
 655                                 if (urb->iso_frame_desc[i].status != -EPROTO)
 656                                         continue;
 657                         }
 658                         if (urb->iso_frame_desc[i].actual_length <= 0) {
 659                                 em28xx_isocdbg("packet %d is empty",i);
 660                                 continue;
 661                         }
 662                         if (urb->iso_frame_desc[i].actual_length >
 663                                                  dev->max_pkt_size) {
 664                                 em28xx_isocdbg("packet bigger than packet size");
 665                                 continue;
 666                         }
 667                         /*new frame */
 668                         if (buf[0] == 0x22 && buf[1] == 0x5a) {
 669                                 em28xx_isocdbg("Video frame, length=%i!",len);
 670
 671                                 if (em28xx_isoc_video(dev,f,&lock_flags,buf[2]))
 672                                 break;
 673                         } else if (buf[0]==0x33 && buf[1]==0x95 && buf[2]==0x00) {
 674                                 em28xx_isocdbg("VBI HEADER!!!");
 675                         }
 676
 677                         /* actual copying */
 678                         if ((*f)->state == F_GRABBING) {
 679                                 em28xx_isoc_video_copy(dev,f,buf, len);
 680                         }
 681                 }
 682         }
 683
 684         for (i = 0; i < urb->number_of_packets; i++) {
 685                 urb->iso_frame_desc[i].status = 0;
 686                 urb->iso_frame_desc[i].actual_length = 0;
 687         }
 688
 689         urb->status = 0;
 690         if ((status = usb_submit_urb(urb, GFP_ATOMIC))) {
 691                 em28xx_errdev("resubmit of urb failed (error=%i)\n", status);
 692                 dev->state |= DEV_MISCONFIGURED;
 693         }
 694         wake_up_interruptible(&dev->wait_frame);
 695         return;
 696 }
 697
 698 /*
 699  * em28xx_uninit_isoc()
 700  * deallocates the buffers and urbs allocated during em28xx_init_iosc()
 701  */
 702 void em28xx_uninit_isoc(struct em28xx *dev)
 703 {
 704         int i;
 705
 706         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
 707                 if (dev->urb[i]) {
 708                         usb_kill_urb(dev->urb[i]);
 709                         if (dev->transfer_buffer[i]){
 710                                 usb_buffer_free(dev->udev,(EM28XX_NUM_PACKETS*dev->max_pkt_size),dev->transfer_buffer[i],dev->urb[i]->transfer_dma);
 711                         }
 712                         usb_free_urb(dev->urb[i]);
 713                 }
 714                 dev->urb[i] = NULL;
 715                 dev->transfer_buffer[i] = NULL;
 716         }
 717         em28xx_capture_start(dev, 0);
 718 }
 719
 720 /*
 721  * em28xx_init_isoc()
 722  * allocates transfer buffers and submits the urbs for isoc transfer
 723  */
 724 int em28xx_init_isoc(struct em28xx *dev)
 725 {
 726         /* change interface to 3 which allows the biggest packet sizes */
 727         int i, errCode;
 728         const int sb_size = EM28XX_NUM_PACKETS * dev->max_pkt_size;
 729
 730         /* reset streaming vars */
 731         dev->frame_current = NULL;
 732         dev->frame_count = 0;
 733
 734         /* allocate urbs */
 735         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
 736                 struct urb *urb;
 737                 int j, k;
 738                 /* allocate transfer buffer */
 739                 urb = usb_alloc_urb(EM28XX_NUM_PACKETS, GFP_KERNEL);
 740                 if (!urb){
 741                         em28xx_errdev("cannot alloc urb %i\n", i);
 742                         em28xx_uninit_isoc(dev);
 743                         return -ENOMEM;
 744                 }
 745                 dev->transfer_buffer[i] = usb_buffer_alloc(dev->udev, sb_size, GFP_KERNEL,&urb->transfer_dma);
 746                 if (!dev->transfer_buffer[i]) {
 747                         em28xx_errdev
 748                                         ("unable to allocate %i bytes for transfer buffer %i\n",
 749                                          sb_size, i);
 750                         em28xx_uninit_isoc(dev);
 751                         usb_free_urb(urb);
 752                         return -ENOMEM;
 753                 }
 754                 memset(dev->transfer_buffer[i], 0, sb_size);
 755                 urb->dev = dev->udev;
 756                 urb->context = dev;
 757                 urb->pipe = usb_rcvisocpipe(dev->udev, 0x82);
 758                 urb->transfer_flags = URB_ISO_ASAP;
 759                 urb->interval = 1;
 760                 urb->transfer_buffer = dev->transfer_buffer[i];
 761                 urb->complete = em28xx_isocIrq;
 762                 urb->number_of_packets = EM28XX_NUM_PACKETS;
 763                 urb->transfer_buffer_length = sb_size;
 764                 for (j = k = 0; j < EM28XX_NUM_PACKETS;
 765                                 j++, k += dev->max_pkt_size) {
 766                         urb->iso_frame_desc[j].offset = k;
 767                         urb->iso_frame_desc[j].length =
 768                                 dev->max_pkt_size;
 769                 }
 770                 dev->urb[i] = urb;
 771         }
 772
 773         /* submit urbs */
 774         for (i = 0; i < EM28XX_NUM_BUFS; i++) {
 775                 errCode = usb_submit_urb(dev->urb[i], GFP_KERNEL);
 776                 if (errCode) {
 777                         em28xx_errdev("submit of urb %i failed (error=%i)\n", i,
 778                                       errCode);
 779                         em28xx_uninit_isoc(dev);
 780                         return errCode;
 781                 }
 782         }
 783
 784         return 0;
 785 }
 786
 787 int em28xx_set_alternate(struct em28xx *dev)
 788 {
 789         int errCode, prev_alt = dev->alt;
 790         dev->alt = alt;
 791         if (dev->alt == 0) {
 792                 int i;
 793                 for(i=0;i< dev->num_alt; i++)
 794                         if(dev->alt_max_pkt_size[i]>dev->alt_max_pkt_size[dev->alt])
 795                                 dev->alt=i;
 796         }
 797
 798         if (dev->alt != prev_alt) {
 799                 dev->max_pkt_size = dev->alt_max_pkt_size[dev->alt];
 800                 em28xx_coredbg("setting alternate %d with wMaxPacketSize=%u\n", dev->alt,
 801                        dev->max_pkt_size);
 802                 errCode = usb_set_interface(dev->udev, 0, dev->alt);
 803                 if (errCode < 0) {
 804                         em28xx_errdev ("cannot change alternate number to %d (error=%i)\n",
 805                                                         dev->alt, errCode);
 806                         return errCode;
 807                 }
 808         }
 809         return 0;
 810 }