drivers/media/video/cpia2/cpia2_usb.c

   1 /****************************************************************************
   2  *
   3  *  Filename: cpia2_usb.c
   4  *
   5  *  Copyright 2001, STMicrolectronics, Inc.
   6  *      Contact:  steve.miller@st.com
   7  *
   8  *  Description:
   9  *     This is a USB driver for CPia2 based video cameras.
  10  *     The infrastructure of this driver is based on the cpia usb driver by
  11  *     Jochen Scharrlach and Johannes Erdfeldt.
  12  *
  13  *  This program is free software; you can redistribute it and/or modify
  14  *  it under the terms of the GNU General Public License as published by
  15  *  the Free Software Foundation; either version 2 of the License, or
  16  *  (at your option) any later version.
  17  *
  18  *  This program is distributed in the hope that it will be useful,
  19  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  *  GNU General Public License for more details.
  22  *
  23  *  You should have received a copy of the GNU General Public License
  24  *  along with this program; if not, write to the Free Software
  25  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  26  *
  27  *  Stripped of 2.4 stuff ready for main kernel submit by
  28  *              Alan Cox <alan@redhat.com>
  29  ****************************************************************************/
  30
  31 #include <linux/kernel.h>
  32 #include <linux/slab.h>
  33 #include <linux/usb.h>
  34
  35 #include "cpia2.h"
  36
  37 static int frame_sizes[] = {
  38         0,      // USBIF_CMDONLY
  39         0,      // USBIF_BULK
  40         128,    // USBIF_ISO_1
  41         384,    // USBIF_ISO_2
  42         640,    // USBIF_ISO_3
  43         768,    // USBIF_ISO_4
  44         896,    // USBIF_ISO_5
  45         1023,   // USBIF_ISO_6
  46 };
  47
  48 #define FRAMES_PER_DESC    10
  49 #define FRAME_SIZE_PER_DESC   frame_sizes[cam->cur_alt]
  50
  51 static void process_frame(struct camera_data *cam);
  52 static void cpia2_usb_complete(struct urb *urb);
  53 static int cpia2_usb_probe(struct usb_interface *intf,
  54                            const struct usb_device_id *id);
  55 static void cpia2_usb_disconnect(struct usb_interface *intf);
  56
  57 static void free_sbufs(struct camera_data *cam);
  58 static void add_APPn(struct camera_data *cam);
  59 static void add_COM(struct camera_data *cam);
  60 static int submit_urbs(struct camera_data *cam);
  61 static int set_alternate(struct camera_data *cam, unsigned int alt);
  62 static int configure_transfer_mode(struct camera_data *cam, unsigned int alt);
  63
  64 static struct usb_device_id cpia2_id_table[] = {
  65         {USB_DEVICE(0x0553, 0x0100)},
  66         {USB_DEVICE(0x0553, 0x0140)},
  67         {USB_DEVICE(0x0553, 0x0151)},  /* STV0676 */
  68         {}                      /* Terminating entry */
  69 };
  70 MODULE_DEVICE_TABLE(usb, cpia2_id_table);
  71
  72 static struct usb_driver cpia2_driver = {
  73         .name           = "cpia2",
  74         .probe          = cpia2_usb_probe,
  75         .disconnect     = cpia2_usb_disconnect,
  76         .id_table       = cpia2_id_table
  77 };
  78
  79
  80 /******************************************************************************
  81  *
  82  *  process_frame
  83  *
  84  *****************************************************************************/
  85 static void process_frame(struct camera_data *cam)
  86 {
  87         static int frame_count = 0;
  88
  89         unsigned char *inbuff = cam->workbuff->data;
  90
  91         DBG("Processing frame #%d, current:%d\n",
  92             cam->workbuff->num, cam->curbuff->num);
  93
  94         if(cam->workbuff->length > cam->workbuff->max_length)
  95                 cam->workbuff->max_length = cam->workbuff->length;
  96
  97         if ((inbuff[0] == 0xFF) && (inbuff[1] == 0xD8)) {
  98                 frame_count++;
  99         } else {
 100                 cam->workbuff->status = FRAME_ERROR;
 101                 DBG("Start of frame not found\n");
 102                 return;
 103         }
 104
 105         /***
 106          * Now the output buffer should have a JPEG image in it.
 107          ***/
 108         if(!cam->first_image_seen) {
 109                 /* Always skip the first image after streaming
 110                  * starts. It is almost certainly corrupt. */
 111                 cam->first_image_seen = 1;
 112                 cam->workbuff->status = FRAME_EMPTY;
 113                 return;
 114         }
 115         if (cam->workbuff->length > 3) {
 116                 if(cam->mmapped &&
 117                    cam->workbuff->length < cam->workbuff->max_length) {
 118                         /* No junk in the buffers */
 119                         memset(cam->workbuff->data+cam->workbuff->length,
 120                                0, cam->workbuff->max_length-
 121                                   cam->workbuff->length);
 122                 }
 123                 cam->workbuff->max_length = cam->workbuff->length;
 124                 cam->workbuff->status = FRAME_READY;
 125
 126                 if(!cam->mmapped && cam->num_frames > 2) {
 127                         /* During normal reading, the most recent
 128                          * frame will be read.  If the current frame
 129                          * hasn't started reading yet, it will never
 130                          * be read, so mark it empty.  If the buffer is
 131                          * mmapped, or we have few buffers, we need to
 132                          * wait for the user to free the buffer.
 133                          *
 134                          * NOTE: This is not entirely foolproof with 3
 135                          * buffers, but it would take an EXTREMELY
 136                          * overloaded system to cause problems (possible
 137                          * image data corruption).  Basically, it would
 138                          * need to take more time to execute cpia2_read
 139                          * than it would for the camera to send
 140                          * cam->num_frames-2 frames before problems
 141                          * could occur.
 142                          */
 143                         cam->curbuff->status = FRAME_EMPTY;
 144                 }
 145                 cam->curbuff = cam->workbuff;
 146                 cam->workbuff = cam->workbuff->next;
 147                 DBG("Changed buffers, work:%d, current:%d\n",
 148                     cam->workbuff->num, cam->curbuff->num);
 149                 return;
 150         } else {
 151                 DBG("Not enough data for an image.\n");
 152         }
 153
 154         cam->workbuff->status = FRAME_ERROR;
 155         return;
 156 }
 157
 158 /******************************************************************************
 159  *
 160  *  add_APPn
 161  *
 162  *  Adds a user specified APPn record
 163  *****************************************************************************/
 164 static void add_APPn(struct camera_data *cam)
 165 {
 166         if(cam->APP_len > 0) {
 167                 cam->workbuff->data[cam->workbuff->length++] = 0xFF;
 168                 cam->workbuff->data[cam->workbuff->length++] = 0xE0+cam->APPn;
 169                 cam->workbuff->data[cam->workbuff->length++] = 0;
 170                 cam->workbuff->data[cam->workbuff->length++] = cam->APP_len+2;
 171                 memcpy(cam->workbuff->data+cam->workbuff->length,
 172                        cam->APP_data, cam->APP_len);
 173                 cam->workbuff->length += cam->APP_len;
 174         }
 175 }
 176
 177 /******************************************************************************
 178  *
 179  *  add_COM
 180  *
 181  *  Adds a user specified COM record
 182  *****************************************************************************/
 183 static void add_COM(struct camera_data *cam)
 184 {
 185         if(cam->COM_len > 0) {
 186                 cam->workbuff->data[cam->workbuff->length++] = 0xFF;
 187                 cam->workbuff->data[cam->workbuff->length++] = 0xFE;
 188                 cam->workbuff->data[cam->workbuff->length++] = 0;
 189                 cam->workbuff->data[cam->workbuff->length++] = cam->COM_len+2;
 190                 memcpy(cam->workbuff->data+cam->workbuff->length,
 191                        cam->COM_data, cam->COM_len);
 192                 cam->workbuff->length += cam->COM_len;
 193         }
 194 }
 195
 196 /******************************************************************************
 197  *
 198  *  cpia2_usb_complete
 199  *
 200  *  callback when incoming packet is received
 201  *****************************************************************************/
 202 static void cpia2_usb_complete(struct urb *urb)
 203 {
 204         int i;
 205         unsigned char *cdata;
 206         static int frame_ready = false;
 207         struct camera_data *cam = (struct camera_data *) urb->context;
 208
 209         if (urb->status!=0) {
 210                 if (!(urb->status == -ENOENT ||
 211                       urb->status == -ECONNRESET ||
 212                       urb->status == -ESHUTDOWN))
 213                 {
 214                         DBG("urb->status = %d!\n", urb->status);
 215                 }
 216                 DBG("Stopping streaming\n");
 217                 return;
 218         }
 219
 220         if (!cam->streaming || !cam->present || cam->open_count == 0) {
 221                 LOG("Will now stop the streaming: streaming = %d, "
 222                     "present=%d, open_count=%d\n",
 223                     cam->streaming, cam->present, cam->open_count);
 224                 return;
 225         }
 226
 227         /***
 228          * Packet collater
 229          ***/
 230         //DBG("Collating %d packets\n", urb->number_of_packets);
 231         for (i = 0; i < urb->number_of_packets; i++) {
 232                 u16 checksum, iso_checksum;
 233                 int j;
 234                 int n = urb->iso_frame_desc[i].actual_length;
 235                 int st = urb->iso_frame_desc[i].status;
 236
 237                 if(cam->workbuff->status == FRAME_READY) {
 238                         struct framebuf *ptr;
 239                         /* Try to find an available buffer */
 240                         DBG("workbuff full, searching\n");
 241                         for (ptr = cam->workbuff->next;
 242                              ptr != cam->workbuff;
 243                              ptr = ptr->next)
 244                         {
 245                                 if (ptr->status == FRAME_EMPTY) {
 246                                         ptr->status = FRAME_READING;
 247                                         ptr->length = 0;
 248                                         break;
 249                                 }
 250                         }
 251                         if (ptr == cam->workbuff)
 252                                 break; /* No READING or EMPTY buffers left */
 253
 254                         cam->workbuff = ptr;
 255                 }
 256
 257                 if (cam->workbuff->status == FRAME_EMPTY ||
 258                     cam->workbuff->status == FRAME_ERROR) {
 259                         cam->workbuff->status = FRAME_READING;
 260                         cam->workbuff->length = 0;
 261                 }
 262
 263                 //DBG("   Packet %d length = %d, status = %d\n", i, n, st);
 264                 cdata = urb->transfer_buffer + urb->iso_frame_desc[i].offset;
 265
 266                 if (st) {
 267                         LOG("cpia2 data error: [%d] len=%d, status = %d\n",
 268                             i, n, st);
 269                         if(!ALLOW_CORRUPT)
 270                                 cam->workbuff->status = FRAME_ERROR;
 271                         continue;
 272                 }
 273
 274                 if(n<=2)
 275                         continue;
 276
 277                 checksum = 0;
 278                 for(j=0; j<n-2; ++j)
 279                         checksum += cdata[j];
 280                 iso_checksum = cdata[j] + cdata[j+1]*256;
 281                 if(checksum != iso_checksum) {
 282                         LOG("checksum mismatch: [%d] len=%d, calculated = %x, checksum = %x\n",
 283                             i, n, (int)checksum, (int)iso_checksum);
 284                         if(!ALLOW_CORRUPT) {
 285                                 cam->workbuff->status = FRAME_ERROR;
 286                                 continue;
 287                         }
 288                 }
 289                 n -= 2;
 290
 291                 if(cam->workbuff->status != FRAME_READING) {
 292                         if((0xFF == cdata[0] && 0xD8 == cdata[1]) ||
 293                            (0xD8 == cdata[0] && 0xFF == cdata[1] &&
 294                             0 != cdata[2])) {
 295                                 /* frame is skipped, but increment total
 296                                  * frame count anyway */
 297                                 cam->frame_count++;
 298                         }
 299                         DBG("workbuff not reading, status=%d\n",
 300                             cam->workbuff->status);
 301                         continue;
 302                 }
 303
 304                 if (cam->frame_size < cam->workbuff->length + n) {
 305                         ERR("buffer overflow! length: %d, n: %d\n",
 306                             cam->workbuff->length, n);
 307                         cam->workbuff->status = FRAME_ERROR;
 308                         if(cam->workbuff->length > cam->workbuff->max_length)
 309                                 cam->workbuff->max_length =
 310                                         cam->workbuff->length;
 311                         continue;
 312                 }
 313
 314                 if (cam->workbuff->length == 0) {
 315                         int data_offset;
 316                         if ((0xD8 == cdata[0]) && (0xFF == cdata[1])) {
 317                                 data_offset = 1;
 318                         } else if((0xFF == cdata[0]) && (0xD8 == cdata[1])
 319                                   && (0xFF == cdata[2])) {
 320                                 data_offset = 2;
 321                         } else {
 322                                 DBG("Ignoring packet, not beginning!\n");
 323                                 continue;
 324                         }
 325                         DBG("Start of frame pattern found\n");
 326                         do_gettimeofday(&cam->workbuff->timestamp);
 327                         cam->workbuff->seq = cam->frame_count++;
 328                         cam->workbuff->data[0] = 0xFF;
 329                         cam->workbuff->data[1] = 0xD8;
 330                         cam->workbuff->length = 2;
 331                         add_APPn(cam);
 332                         add_COM(cam);
 333                         memcpy(cam->workbuff->data+cam->workbuff->length,
 334                                cdata+data_offset, n-data_offset);
 335                         cam->workbuff->length += n-data_offset;
 336                 } else if (cam->workbuff->length > 0) {
 337                         memcpy(cam->workbuff->data + cam->workbuff->length,
 338                                cdata, n);
 339                         cam->workbuff->length += n;
 340                 }
 341
 342                 if ((cam->workbuff->length >= 3) &&
 343                     (cam->workbuff->data[cam->workbuff->length - 3] == 0xFF) &&
 344                     (cam->workbuff->data[cam->workbuff->length - 2] == 0xD9) &&
 345                     (cam->workbuff->data[cam->workbuff->length - 1] == 0xFF)) {
 346                         frame_ready = true;
 347                         cam->workbuff->data[cam->workbuff->length - 1] = 0;
 348                         cam->workbuff->length -= 1;
 349                 } else if ((cam->workbuff->length >= 2) &&
 350                    (cam->workbuff->data[cam->workbuff->length - 2] == 0xFF) &&
 351                    (cam->workbuff->data[cam->workbuff->length - 1] == 0xD9)) {
 352                         frame_ready = true;
 353                 }
 354
 355                 if (frame_ready) {
 356                         DBG("Workbuff image size = %d\n",cam->workbuff->length);
 357                         process_frame(cam);
 358
 359                         frame_ready = false;
 360
 361                         if (waitqueue_active(&cam->wq_stream))
 362                                 wake_up_interruptible(&cam->wq_stream);
 363                 }
 364         }
 365
 366         if(cam->streaming) {
 367                 /* resubmit */
 368                 urb->dev = cam->dev;
 369                 if ((i = usb_submit_urb(urb, GFP_ATOMIC)) != 0)
 370                         ERR("%s: usb_submit_urb ret %d!\n", __func__, i);
 371         }
 372 }
 373
 374 /******************************************************************************
 375  *
 376  * configure_transfer_mode
 377  *
 378  *****************************************************************************/
 379 static int configure_transfer_mode(struct camera_data *cam, unsigned int alt)
 380 {
 381         static unsigned char iso_regs[8][4] = {
 382                 {0x00, 0x00, 0x00, 0x00},
 383                 {0x00, 0x00, 0x00, 0x00},
 384                 {0xB9, 0x00, 0x00, 0x7E},
 385                 {0xB9, 0x00, 0x01, 0x7E},
 386                 {0xB9, 0x00, 0x02, 0x7E},
 387                 {0xB9, 0x00, 0x02, 0xFE},
 388                 {0xB9, 0x00, 0x03, 0x7E},
 389                 {0xB9, 0x00, 0x03, 0xFD}
 390         };
 391         struct cpia2_command cmd;
 392         unsigned char reg;
 393
 394         if(!cam->present)
 395                 return -ENODEV;
 396
 397         /***
 398          * Write the isoc registers according to the alternate selected
 399          ***/
 400         cmd.direction = TRANSFER_WRITE;
 401         cmd.buffer.block_data[0] = iso_regs[alt][0];
 402         cmd.buffer.block_data[1] = iso_regs[alt][1];
 403         cmd.buffer.block_data[2] = iso_regs[alt][2];
 404         cmd.buffer.block_data[3] = iso_regs[alt][3];
 405         cmd.req_mode = CAMERAACCESS_TYPE_BLOCK | CAMERAACCESS_VC;
 406         cmd.start = CPIA2_VC_USB_ISOLIM;
 407         cmd.reg_count = 4;
 408         cpia2_send_command(cam, &cmd);
 409
 410         /***
 411          * Enable relevant streams before starting polling.
 412          * First read USB Stream Config Register.
 413          ***/
 414         cmd.direction = TRANSFER_READ;
 415         cmd.req_mode = CAMERAACCESS_TYPE_BLOCK | CAMERAACCESS_VC;
 416         cmd.start = CPIA2_VC_USB_STRM;
 417         cmd.reg_count = 1;
 418         cpia2_send_command(cam, &cmd);
 419         reg = cmd.buffer.block_data[0];
 420
 421         /* Clear iso, bulk, and int */
 422         reg &= ~(CPIA2_VC_USB_STRM_BLK_ENABLE |
 423                  CPIA2_VC_USB_STRM_ISO_ENABLE |
 424                  CPIA2_VC_USB_STRM_INT_ENABLE);
 425
 426         if (alt == USBIF_BULK) {
 427                 DBG("Enabling bulk xfer\n");
 428                 reg |= CPIA2_VC_USB_STRM_BLK_ENABLE;    /* Enable Bulk */
 429                 cam->xfer_mode = XFER_BULK;
 430         } else if (alt >= USBIF_ISO_1) {
 431                 DBG("Enabling ISOC xfer\n");
 432                 reg |= CPIA2_VC_USB_STRM_ISO_ENABLE;
 433                 cam->xfer_mode = XFER_ISOC;
 434         }
 435
 436         cmd.buffer.block_data[0] = reg;
 437         cmd.direction = TRANSFER_WRITE;
 438         cmd.start = CPIA2_VC_USB_STRM;
 439         cmd.reg_count = 1;
 440         cmd.req_mode = CAMERAACCESS_TYPE_BLOCK | CAMERAACCESS_VC;
 441         cpia2_send_command(cam, &cmd);
 442
 443         return 0;
 444 }
 445
 446 /******************************************************************************
 447  *
 448  * cpia2_usb_change_streaming_alternate
 449  *
 450  *****************************************************************************/
 451 int cpia2_usb_change_streaming_alternate(struct camera_data *cam,
 452                                          unsigned int alt)
 453 {
 454         int ret = 0;
 455
 456         if(alt < USBIF_ISO_1 || alt > USBIF_ISO_6)
 457                 return -EINVAL;
 458
 459         if(alt == cam->params.camera_state.stream_mode)
 460                 return 0;
 461
 462         cpia2_usb_stream_pause(cam);
 463
 464         configure_transfer_mode(cam, alt);
 465
 466         cam->params.camera_state.stream_mode = alt;
 467
 468         /* Reset the camera to prevent image quality degradation */
 469         cpia2_reset_camera(cam);
 470
 471         cpia2_usb_stream_resume(cam);
 472
 473         return ret;
 474 }
 475
 476 /******************************************************************************
 477  *
 478  * set_alternate
 479  *
 480  *****************************************************************************/
 481 int set_alternate(struct camera_data *cam, unsigned int alt)
 482 {
 483         int ret = 0;
 484
 485         if(alt == cam->cur_alt)
 486                 return 0;
 487
 488         if (cam->cur_alt != USBIF_CMDONLY) {
 489                 DBG("Changing from alt %d to %d\n", cam->cur_alt, USBIF_CMDONLY);
 490                 ret = usb_set_interface(cam->dev, cam->iface, USBIF_CMDONLY);
 491                 if (ret != 0)
 492                         return ret;
 493         }
 494         if (alt != USBIF_CMDONLY) {
 495                 DBG("Changing from alt %d to %d\n", USBIF_CMDONLY, alt);
 496                 ret = usb_set_interface(cam->dev, cam->iface, alt);
 497                 if (ret != 0)
 498                         return ret;
 499         }
 500
 501         cam->old_alt = cam->cur_alt;
 502         cam->cur_alt = alt;
 503
 504         return ret;
 505 }
 506
 507 /******************************************************************************
 508  *
 509  * free_sbufs
 510  *
 511  * Free all cam->sbuf[]. All non-NULL .data and .urb members that are non-NULL
 512  * are assumed to be allocated. Non-NULL .urb members are also assumed to be
 513  * submitted (and must therefore be killed before they are freed).
 514  *****************************************************************************/
 515 static void free_sbufs(struct camera_data *cam)
 516 {
 517         int i;
 518
 519         for (i = 0; i < NUM_SBUF; i++) {
 520                 if(cam->sbuf[i].urb) {
 521                         usb_kill_urb(cam->sbuf[i].urb);
 522                         usb_free_urb(cam->sbuf[i].urb);
 523                         cam->sbuf[i].urb = NULL;
 524                 }
 525                 if(cam->sbuf[i].data) {
 526                         kfree(cam->sbuf[i].data);
 527                         cam->sbuf[i].data = NULL;
 528                 }
 529         }
 530 }
 531
 532 /*******
 533 * Convenience functions
 534 *******/
 535 /****************************************************************************
 536  *
 537  *  write_packet
 538  *
 539  ***************************************************************************/
 540 static int write_packet(struct usb_device *udev,
 541                         u8 request, u8 * registers, u16 start, size_t size)
 542 {
 543         if (!registers || size <= 0)
 544                 return -EINVAL;
 545
 546         return usb_control_msg(udev,
 547                                usb_sndctrlpipe(udev, 0),
 548                                request,
 549                                USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 550                                start,   /* value */
 551                                0,       /* index */
 552                                registers,       /* buffer */
 553                                size,
 554                                HZ);
 555 }
 556
 557 /****************************************************************************
 558  *
 559  *  read_packet
 560  *
 561  ***************************************************************************/
 562 static int read_packet(struct usb_device *udev,
 563                        u8 request, u8 * registers, u16 start, size_t size)
 564 {
 565         if (!registers || size <= 0)
 566                 return -EINVAL;
 567
 568         return usb_control_msg(udev,
 569                                usb_rcvctrlpipe(udev, 0),
 570                                request,
 571                                USB_DIR_IN|USB_TYPE_VENDOR|USB_RECIP_DEVICE,
 572                                start,   /* value */
 573                                0,       /* index */
 574                                registers,       /* buffer */
 575                                size,
 576                                HZ);
 577 }
 578
 579 /******************************************************************************
 580  *
 581  *  cpia2_usb_transfer_cmd
 582  *
 583  *****************************************************************************/
 584 int cpia2_usb_transfer_cmd(struct camera_data *cam,
 585                            void *registers,
 586                            u8 request, u8 start, u8 count, u8 direction)
 587 {
 588         int err = 0;
 589         struct usb_device *udev = cam->dev;
 590
 591         if (!udev) {
 592                 ERR("%s: Internal driver error: udev is NULL\n", __func__);
 593                 return -EINVAL;
 594         }
 595
 596         if (!registers) {
 597                 ERR("%s: Internal driver error: register array is NULL\n", __func__);
 598                 return -EINVAL;
 599         }
 600
 601         if (direction == TRANSFER_READ) {
 602                 err = read_packet(udev, request, (u8 *)registers, start, count);
 603                 if (err > 0)
 604                         err = 0;
 605         } else if (direction == TRANSFER_WRITE) {
 606                 err =write_packet(udev, request, (u8 *)registers, start, count);
 607                 if (err < 0) {
 608                         LOG("Control message failed, err val = %d\n", err);
 609                         LOG("Message: request = 0x%0X, start = 0x%0X\n",
 610                             request, start);
 611                         LOG("Message: count = %d, register[0] = 0x%0X\n",
 612                             count, ((unsigned char *) registers)[0]);
 613                 } else
 614                         err=0;
 615         } else {
 616                 LOG("Unexpected first byte of direction: %d\n",
 617                        direction);
 618                 return -EINVAL;
 619         }
 620
 621         if(err != 0)
 622                 LOG("Unexpected error: %d\n", err);
 623         return err;
 624 }
 625
 626
 627 /******************************************************************************
 628  *
 629  *  submit_urbs
 630  *
 631  *****************************************************************************/
 632 static int submit_urbs(struct camera_data *cam)
 633 {
 634         struct urb *urb;
 635         int fx, err, i;
 636
 637         for(i=0; i<NUM_SBUF; ++i) {
 638                 if (cam->sbuf[i].data)
 639                         continue;
 640                 cam->sbuf[i].data =
 641                     kmalloc(FRAMES_PER_DESC * FRAME_SIZE_PER_DESC, GFP_KERNEL);
 642                 if (!cam->sbuf[i].data) {
 643                         while (--i >= 0) {
 644                                 kfree(cam->sbuf[i].data);
 645                                 cam->sbuf[i].data = NULL;
 646                         }
 647                         return -ENOMEM;
 648                 }
 649         }
 650
 651         /* We double buffer the Isoc lists, and also know the polling
 652          * interval is every frame (1 == (1 << (bInterval -1))).
 653          */
 654         for(i=0; i<NUM_SBUF; ++i) {
 655                 if(cam->sbuf[i].urb) {
 656                         continue;
 657                 }
 658                 urb = usb_alloc_urb(FRAMES_PER_DESC, GFP_KERNEL);
 659                 if (!urb) {
 660                         return -ENOMEM;
 661                 }
 662
 663                 cam->sbuf[i].urb = urb;
 664                 urb->dev = cam->dev;
 665                 urb->context = cam;
 666                 urb->pipe = usb_rcvisocpipe(cam->dev, 1 /*ISOC endpoint*/);
 667                 urb->transfer_flags = URB_ISO_ASAP;
 668                 urb->transfer_buffer = cam->sbuf[i].data;
 669                 urb->complete = cpia2_usb_complete;
 670                 urb->number_of_packets = FRAMES_PER_DESC;
 671                 urb->interval = 1;
 672                 urb->transfer_buffer_length =
 673                         FRAME_SIZE_PER_DESC * FRAMES_PER_DESC;
 674
 675                 for (fx = 0; fx < FRAMES_PER_DESC; fx++) {
 676                         urb->iso_frame_desc[fx].offset =
 677                                 FRAME_SIZE_PER_DESC * fx;
 678                         urb->iso_frame_desc[fx].length = FRAME_SIZE_PER_DESC;
 679                 }
 680         }
 681
 682
 683         /* Queue the ISO urbs, and resubmit in the completion handler */
 684         for(i=0; i<NUM_SBUF; ++i) {
 685                 err = usb_submit_urb(cam->sbuf[i].urb, GFP_KERNEL);
 686                 if (err) {
 687                         ERR("usb_submit_urb[%d]() = %d\n", i, err);
 688                         return err;
 689                 }
 690         }
 691
 692         return 0;
 693 }
 694
 695 /******************************************************************************
 696  *
 697  *  cpia2_usb_stream_start
 698  *
 699  *****************************************************************************/
 700 int cpia2_usb_stream_start(struct camera_data *cam, unsigned int alternate)
 701 {
 702         int ret;
 703         int old_alt;
 704
 705         if(cam->streaming)
 706                 return 0;
 707
 708         if (cam->flush) {
 709                 int i;
 710                 DBG("Flushing buffers\n");
 711                 for(i=0; i<cam->num_frames; ++i) {
 712                         cam->buffers[i].status = FRAME_EMPTY;
 713                         cam->buffers[i].length = 0;
 714                 }
 715                 cam->curbuff = &cam->buffers[0];
 716                 cam->workbuff = cam->curbuff->next;
 717                 cam->flush = false;
 718         }
 719
 720         old_alt = cam->params.camera_state.stream_mode;
 721         cam->params.camera_state.stream_mode = 0;
 722         ret = cpia2_usb_change_streaming_alternate(cam, alternate);
 723         if (ret < 0) {
 724                 int ret2;
 725                 ERR("cpia2_usb_change_streaming_alternate() = %d!\n", ret);
 726                 cam->params.camera_state.stream_mode = old_alt;
 727                 ret2 = set_alternate(cam, USBIF_CMDONLY);
 728                 if (ret2 < 0) {
 729                         ERR("cpia2_usb_change_streaming_alternate(%d) =%d has already "
 730                             "failed. Then tried to call "
 731                             "set_alternate(USBIF_CMDONLY) = %d.\n",
 732                             alternate, ret, ret2);
 733                 }
 734         } else {
 735                 cam->frame_count = 0;
 736                 cam->streaming = 1;
 737                 ret = cpia2_usb_stream_resume(cam);
 738         }
 739         return ret;
 740 }
 741
 742 /******************************************************************************
 743  *
 744  *  cpia2_usb_stream_pause
 745  *
 746  *****************************************************************************/
 747 int cpia2_usb_stream_pause(struct camera_data *cam)
 748 {
 749         int ret = 0;
 750         if(cam->streaming) {
 751                 ret = set_alternate(cam, USBIF_CMDONLY);
 752                 free_sbufs(cam);
 753         }
 754         return ret;
 755 }
 756
 757 /******************************************************************************
 758  *
 759  *  cpia2_usb_stream_resume
 760  *
 761  *****************************************************************************/
 762 int cpia2_usb_stream_resume(struct camera_data *cam)
 763 {
 764         int ret = 0;
 765         if(cam->streaming) {
 766                 cam->first_image_seen = 0;
 767                 ret = set_alternate(cam, cam->params.camera_state.stream_mode);
 768                 if(ret == 0) {
 769                         ret = submit_urbs(cam);
 770                 }
 771         }
 772         return ret;
 773 }
 774
 775 /******************************************************************************
 776  *
 777  *  cpia2_usb_stream_stop
 778  *
 779  *****************************************************************************/
 780 int cpia2_usb_stream_stop(struct camera_data *cam)
 781 {
 782         int ret;
 783         ret = cpia2_usb_stream_pause(cam);
 784         cam->streaming = 0;
 785         configure_transfer_mode(cam, 0);
 786         return ret;
 787 }
 788
 789 /******************************************************************************
 790  *
 791  *  cpia2_usb_probe
 792  *
 793  *  Probe and initialize.
 794  *****************************************************************************/
 795 static int cpia2_usb_probe(struct usb_interface *intf,
 796                            const struct usb_device_id *id)
 797 {
 798         struct usb_device *udev = interface_to_usbdev(intf);
 799         struct usb_interface_descriptor *interface;
 800         struct camera_data *cam;
 801         int ret;
 802
 803         /* A multi-config CPiA2 camera? */
 804         if (udev->descriptor.bNumConfigurations != 1)
 805                 return -ENODEV;
 806         interface = &intf->cur_altsetting->desc;
 807
 808         /* If we get to this point, we found a CPiA2 camera */
 809         LOG("CPiA2 USB camera found\n");
 810
 811         if((cam = cpia2_init_camera_struct()) == NULL)
 812                 return -ENOMEM;
 813
 814         cam->dev = udev;
 815         cam->iface = interface->bInterfaceNumber;
 816
 817         ret = set_alternate(cam, USBIF_CMDONLY);
 818         if (ret < 0) {
 819                 ERR("%s: usb_set_interface error (ret = %d)\n", __func__, ret);
 820                 kfree(cam);
 821                 return ret;
 822         }
 823
 824         if ((ret = cpia2_register_camera(cam)) < 0) {
 825                 ERR("%s: Failed to register cpia2 camera (ret = %d)\n", __func__, ret);
 826                 kfree(cam);
 827                 return ret;
 828         }
 829
 830
 831         if((ret = cpia2_init_camera(cam)) < 0) {
 832                 ERR("%s: failed to initialize cpia2 camera (ret = %d)\n", __func__, ret);
 833                 cpia2_unregister_camera(cam);
 834                 kfree(cam);
 835                 return ret;
 836         }
 837         LOG("  CPiA Version: %d.%02d (%d.%d)\n",
 838                cam->params.version.firmware_revision_hi,
 839                cam->params.version.firmware_revision_lo,
 840                cam->params.version.asic_id,
 841                cam->params.version.asic_rev);
 842         LOG("  CPiA PnP-ID: %04x:%04x:%04x\n",
 843                cam->params.pnp_id.vendor,
 844                cam->params.pnp_id.product,
 845                cam->params.pnp_id.device_revision);
 846         LOG("  SensorID: %d.(version %d)\n",
 847                cam->params.version.sensor_flags,
 848                cam->params.version.sensor_rev);
 849
 850         usb_set_intfdata(intf, cam);
 851
 852         return 0;
 853 }
 854
 855 /******************************************************************************
 856  *
 857  *  cpia2_disconnect
 858  *
 859  *****************************************************************************/
 860 static void cpia2_usb_disconnect(struct usb_interface *intf)
 861 {
 862         struct camera_data *cam = usb_get_intfdata(intf);
 863         usb_set_intfdata(intf, NULL);
 864         cam->present = 0;
 865
 866         DBG("Stopping stream\n");
 867         cpia2_usb_stream_stop(cam);
 868
 869         DBG("Unregistering camera\n");
 870         cpia2_unregister_camera(cam);
 871
 872         if(cam->buffers) {
 873                 DBG("Wakeup waiting processes\n");
 874                 cam->curbuff->status = FRAME_READY;
 875                 cam->curbuff->length = 0;
 876                 if (waitqueue_active(&cam->wq_stream))
 877                         wake_up_interruptible(&cam->wq_stream);
 878         }
 879
 880         DBG("Releasing interface\n");
 881         usb_driver_release_interface(&cpia2_driver, intf);
 882
 883         if (cam->open_count == 0) {
 884                 DBG("Freeing camera structure\n");
 885                 kfree(cam);
 886         }
 887
 888         LOG("CPiA2 camera disconnected.\n");
 889 }
 890
 891
 892 /******************************************************************************
 893  *
 894  *  usb_cpia2_init
 895  *
 896  *****************************************************************************/
 897 int cpia2_usb_init(void)
 898 {
 899         return usb_register(&cpia2_driver);
 900 }
 901
 902 /******************************************************************************
 903  *
 904  *  usb_cpia_cleanup
 905  *
 906  *****************************************************************************/
 907 void cpia2_usb_cleanup(void)
 908 {
 909         schedule_timeout(2 * HZ);
 910         usb_deregister(&cpia2_driver);
 911 }