drivers/media/video/cpia_usb.c

   1 /*
   2  * cpia_usb CPiA USB driver
   3  *
   4  * Supports CPiA based parallel port Video Camera's.
   5  *
   6  * Copyright (C) 1999        Jochen Scharrlach <Jochen.Scharrlach@schwaben.de>
   7  * Copyright (C) 1999, 2000  Johannes Erdfelt <johannes@erdfelt.com>
   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 /* define _CPIA_DEBUG_ for verbose debug output (see cpia.h) */
  25 /* #define _CPIA_DEBUG_  1 */
  26
  27 #include <linux/module.h>
  28 #include <linux/kernel.h>
  29 #include <linux/init.h>
  30 #include <linux/wait.h>
  31 #include <linux/list.h>
  32 #include <linux/slab.h>
  33 #include <linux/vmalloc.h>
  34 #include <linux/usb.h>
  35
  36 #include "cpia.h"
  37
  38 #define USB_REQ_CPIA_GRAB_FRAME                 0xC1
  39 #define USB_REQ_CPIA_UPLOAD_FRAME               0xC2
  40 #define  WAIT_FOR_NEXT_FRAME                    0
  41 #define  FORCE_FRAME_UPLOAD                     1
  42
  43 #define FRAMES_PER_DESC         10
  44 #define FRAME_SIZE_PER_DESC     960     /* Shouldn't be hardcoded */
  45 #define CPIA_NUMSBUF            2
  46 #define STREAM_BUF_SIZE         (PAGE_SIZE * 4)
  47 #define SCRATCH_BUF_SIZE        (STREAM_BUF_SIZE * 2)
  48
  49 struct cpia_sbuf {
  50         char *data;
  51         struct urb *urb;
  52 };
  53
  54 #define FRAMEBUF_LEN (CPIA_MAX_FRAME_SIZE+100)
  55 enum framebuf_status {
  56         FRAME_EMPTY,
  57         FRAME_READING,
  58         FRAME_READY,
  59         FRAME_ERROR,
  60 };
  61
  62 struct framebuf {
  63         int length;
  64         enum framebuf_status status;
  65         u8 data[FRAMEBUF_LEN];
  66         struct framebuf *next;
  67 };
  68
  69 struct usb_cpia {
  70         /* Device structure */
  71         struct usb_device *dev;
  72
  73         unsigned char iface;
  74         wait_queue_head_t wq_stream;
  75
  76         int cursbuf;            /* Current receiving sbuf */
  77         struct cpia_sbuf sbuf[CPIA_NUMSBUF];            /* Double buffering */
  78
  79         int streaming;
  80         int open;
  81         int present;
  82         struct framebuf *buffers[3];
  83         struct framebuf *curbuff, *workbuff;
  84 };
  85
  86 static int cpia_usb_open(void *privdata);
  87 static int cpia_usb_registerCallback(void *privdata, void (*cb) (void *cbdata),
  88                                      void *cbdata);
  89 static int cpia_usb_transferCmd(void *privdata, u8 *command, u8 *data);
  90 static int cpia_usb_streamStart(void *privdata);
  91 static int cpia_usb_streamStop(void *privdata);
  92 static int cpia_usb_streamRead(void *privdata, u8 *frame, int noblock);
  93 static int cpia_usb_close(void *privdata);
  94
  95 #define ABOUT "USB driver for Vision CPiA based cameras"
  96
  97 static struct cpia_camera_ops cpia_usb_ops = {
  98         cpia_usb_open,
  99         cpia_usb_registerCallback,
 100         cpia_usb_transferCmd,
 101         cpia_usb_streamStart,
 102         cpia_usb_streamStop,
 103         cpia_usb_streamRead,
 104         cpia_usb_close,
 105         0,
 106         THIS_MODULE
 107 };
 108
 109 static LIST_HEAD(cam_list);
 110 static spinlock_t cam_list_lock_usb;
 111
 112 static void cpia_usb_complete(struct urb *urb, struct pt_regs *regs)
 113 {
 114         int i;
 115         char *cdata;
 116         struct usb_cpia *ucpia;
 117
 118         if (!urb || !urb->context)
 119                 return;
 120
 121         ucpia = (struct usb_cpia *) urb->context;
 122
 123         if (!ucpia->dev || !ucpia->streaming || !ucpia->present || !ucpia->open)
 124                 return;
 125
 126         if (ucpia->workbuff->status == FRAME_EMPTY) {
 127                 ucpia->workbuff->status = FRAME_READING;
 128                 ucpia->workbuff->length = 0;
 129         }
 130
 131         for (i = 0; i < urb->number_of_packets; i++) {
 132                 int n = urb->iso_frame_desc[i].actual_length;
 133                 int st = urb->iso_frame_desc[i].status;
 134
 135                 cdata = urb->transfer_buffer + urb->iso_frame_desc[i].offset;
 136
 137                 if (st)
 138                         printk(KERN_DEBUG "cpia data error: [%d] len=%d, status=%X\n", i, n, st);
 139
 140                 if (FRAMEBUF_LEN < ucpia->workbuff->length + n) {
 141                         printk(KERN_DEBUG "cpia: scratch buf overflow!scr_len: %d, n: %d\n", ucpia->workbuff->length, n);
 142                         return;
 143                 }
 144
 145                 if (n) {
 146                         if ((ucpia->workbuff->length > 0) ||
 147                             (0x19 == cdata[0] && 0x68 == cdata[1])) {
 148                                 memcpy(ucpia->workbuff->data + ucpia->workbuff->length, cdata, n);
 149                                 ucpia->workbuff->length += n;
 150                         } else
 151                                 DBG("Ignoring packet!\n");
 152                 } else {
 153                         if (ucpia->workbuff->length > 4 &&
 154                             0xff == ucpia->workbuff->data[ucpia->workbuff->length-1] &&
 155                             0xff == ucpia->workbuff->data[ucpia->workbuff->length-2] &&
 156                             0xff == ucpia->workbuff->data[ucpia->workbuff->length-3] &&
 157                             0xff == ucpia->workbuff->data[ucpia->workbuff->length-4]) {
 158                                 ucpia->workbuff->status = FRAME_READY;
 159                                 ucpia->curbuff = ucpia->workbuff;
 160                                 ucpia->workbuff = ucpia->workbuff->next;
 161                                 ucpia->workbuff->status = FRAME_EMPTY;
 162                                 ucpia->workbuff->length = 0;
 163
 164                                 if (waitqueue_active(&ucpia->wq_stream))
 165                                         wake_up_interruptible(&ucpia->wq_stream);
 166                         }
 167                 }
 168         }
 169
 170         /* resubmit */
 171         urb->dev = ucpia->dev;
 172         if ((i = usb_submit_urb(urb, GFP_ATOMIC)) != 0)
 173                 printk(KERN_ERR "%s: usb_submit_urb ret %d\n", __FUNCTION__,  i);
 174 }
 175
 176 static int cpia_usb_open(void *privdata)
 177 {
 178         struct usb_cpia *ucpia = (struct usb_cpia *) privdata;
 179         struct urb *urb;
 180         int ret, retval = 0, fx, err;
 181
 182         if (!ucpia)
 183                 return -EINVAL;
 184
 185         ucpia->sbuf[0].data = kmalloc(FRAMES_PER_DESC * FRAME_SIZE_PER_DESC, GFP_KERNEL);
 186         if (!ucpia->sbuf[0].data)
 187                 return -EINVAL;
 188
 189         ucpia->sbuf[1].data = kmalloc(FRAMES_PER_DESC * FRAME_SIZE_PER_DESC, GFP_KERNEL);
 190         if (!ucpia->sbuf[1].data) {
 191                 retval = -EINVAL;
 192                 goto error_0;
 193         }
 194
 195         ret = usb_set_interface(ucpia->dev, ucpia->iface, 3);
 196         if (ret < 0) {
 197                 printk(KERN_ERR "cpia_usb_open: usb_set_interface error (ret = %d)\n", ret);
 198                 retval = -EBUSY;
 199                 goto error_1;
 200         }
 201
 202         ucpia->buffers[0]->status = FRAME_EMPTY;
 203         ucpia->buffers[0]->length = 0;
 204         ucpia->buffers[1]->status = FRAME_EMPTY;
 205         ucpia->buffers[1]->length = 0;
 206         ucpia->buffers[2]->status = FRAME_EMPTY;
 207         ucpia->buffers[2]->length = 0;
 208         ucpia->curbuff = ucpia->buffers[0];
 209         ucpia->workbuff = ucpia->buffers[1];
 210
 211         /* We double buffer the Iso lists, and also know the polling
 212          * interval is every frame (1 == (1 << (bInterval -1))).
 213          */
 214         urb = usb_alloc_urb(FRAMES_PER_DESC, GFP_KERNEL);
 215         if (!urb) {
 216                 printk(KERN_ERR "cpia_init_isoc: usb_alloc_urb 0\n");
 217                 retval = -ENOMEM;
 218                 goto error_1;
 219         }
 220
 221         ucpia->sbuf[0].urb = urb;
 222         urb->dev = ucpia->dev;
 223         urb->context = ucpia;
 224         urb->pipe = usb_rcvisocpipe(ucpia->dev, 1);
 225         urb->transfer_flags = URB_ISO_ASAP;
 226         urb->transfer_buffer = ucpia->sbuf[0].data;
 227         urb->complete = cpia_usb_complete;
 228         urb->number_of_packets = FRAMES_PER_DESC;
 229         urb->interval = 1;
 230         urb->transfer_buffer_length = FRAME_SIZE_PER_DESC * FRAMES_PER_DESC;
 231         for (fx = 0; fx < FRAMES_PER_DESC; fx++) {
 232                 urb->iso_frame_desc[fx].offset = FRAME_SIZE_PER_DESC * fx;
 233                 urb->iso_frame_desc[fx].length = FRAME_SIZE_PER_DESC;
 234         }
 235
 236         urb = usb_alloc_urb(FRAMES_PER_DESC, GFP_KERNEL);
 237         if (!urb) {
 238                 printk(KERN_ERR "cpia_init_isoc: usb_alloc_urb 1\n");
 239                 retval = -ENOMEM;
 240                 goto error_urb0;
 241         }
 242
 243         ucpia->sbuf[1].urb = urb;
 244         urb->dev = ucpia->dev;
 245         urb->context = ucpia;
 246         urb->pipe = usb_rcvisocpipe(ucpia->dev, 1);
 247         urb->transfer_flags = URB_ISO_ASAP;
 248         urb->transfer_buffer = ucpia->sbuf[1].data;
 249         urb->complete = cpia_usb_complete;
 250         urb->number_of_packets = FRAMES_PER_DESC;
 251         urb->interval = 1;
 252         urb->transfer_buffer_length = FRAME_SIZE_PER_DESC * FRAMES_PER_DESC;
 253         for (fx = 0; fx < FRAMES_PER_DESC; fx++) {
 254                 urb->iso_frame_desc[fx].offset = FRAME_SIZE_PER_DESC * fx;
 255                 urb->iso_frame_desc[fx].length = FRAME_SIZE_PER_DESC;
 256         }
 257
 258         /* queue the ISO urbs, and resubmit in the completion handler */
 259         err = usb_submit_urb(ucpia->sbuf[0].urb, GFP_KERNEL);
 260         if (err) {
 261                 printk(KERN_ERR "cpia_init_isoc: usb_submit_urb 0 ret %d\n",
 262                         err);
 263                 goto error_urb1;
 264         }
 265         err = usb_submit_urb(ucpia->sbuf[1].urb, GFP_KERNEL);
 266         if (err) {
 267                 printk(KERN_ERR "cpia_init_isoc: usb_submit_urb 1 ret %d\n",
 268                         err);
 269                 goto error_urb1;
 270         }
 271
 272         ucpia->streaming = 1;
 273         ucpia->open = 1;
 274
 275         return 0;
 276
 277 error_urb1:             /* free urb 1 */
 278         usb_free_urb(ucpia->sbuf[1].urb);
 279         ucpia->sbuf[1].urb = NULL;
 280 error_urb0:             /* free urb 0 */
 281         usb_free_urb(ucpia->sbuf[0].urb);
 282         ucpia->sbuf[0].urb = NULL;
 283 error_1:
 284         kfree (ucpia->sbuf[1].data);
 285         ucpia->sbuf[1].data = NULL;
 286 error_0:
 287         kfree (ucpia->sbuf[0].data);
 288         ucpia->sbuf[0].data = NULL;
 289
 290         return retval;
 291 }
 292
 293 //
 294 // convenience functions
 295 //
 296
 297 /****************************************************************************
 298  *
 299  *  WritePacket
 300  *
 301  ***************************************************************************/
 302 static int WritePacket(struct usb_device *udev, const u8 *packet, u8 *buf, size_t size)
 303 {
 304         if (!packet)
 305                 return -EINVAL;
 306
 307         return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
 308                          packet[1] + (packet[0] << 8),
 309                          USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 310                          packet[2] + (packet[3] << 8),
 311                          packet[4] + (packet[5] << 8), buf, size, 1000);
 312 }
 313
 314 /****************************************************************************
 315  *
 316  *  ReadPacket
 317  *
 318  ***************************************************************************/
 319 static int ReadPacket(struct usb_device *udev, u8 *packet, u8 *buf, size_t size)
 320 {
 321         if (!packet || size <= 0)
 322                 return -EINVAL;
 323
 324         return usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
 325                          packet[1] + (packet[0] << 8),
 326                          USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
 327                          packet[2] + (packet[3] << 8),
 328                          packet[4] + (packet[5] << 8), buf, size, 1000);
 329 }
 330
 331 static int cpia_usb_transferCmd(void *privdata, u8 *command, u8 *data)
 332 {
 333         int err = 0;
 334         int databytes;
 335         struct usb_cpia *ucpia = (struct usb_cpia *)privdata;
 336         struct usb_device *udev = ucpia->dev;
 337
 338         if (!udev) {
 339                 DBG("Internal driver error: udev is NULL\n");
 340                 return -EINVAL;
 341         }
 342
 343         if (!command) {
 344                 DBG("Internal driver error: command is NULL\n");
 345                 return -EINVAL;
 346         }
 347
 348         databytes = (((int)command[7])<<8) | command[6];
 349
 350         if (command[0] == DATA_IN) {
 351                 u8 buffer[8];
 352
 353                 if (!data) {
 354                         DBG("Internal driver error: data is NULL\n");
 355                         return -EINVAL;
 356                 }
 357
 358                 err = ReadPacket(udev, command, buffer, 8);
 359                 if (err < 0)
 360                         return err;
 361
 362                 memcpy(data, buffer, databytes);
 363         } else if(command[0] == DATA_OUT)
 364                 WritePacket(udev, command, data, databytes);
 365         else {
 366                 DBG("Unexpected first byte of command: %x\n", command[0]);
 367                 err = -EINVAL;
 368         }
 369
 370         return 0;
 371 }
 372
 373 static int cpia_usb_registerCallback(void *privdata, void (*cb) (void *cbdata),
 374         void *cbdata)
 375 {
 376         return -ENODEV;
 377 }
 378
 379 static int cpia_usb_streamStart(void *privdata)
 380 {
 381         return -ENODEV;
 382 }
 383
 384 static int cpia_usb_streamStop(void *privdata)
 385 {
 386         return -ENODEV;
 387 }
 388
 389 static int cpia_usb_streamRead(void *privdata, u8 *frame, int noblock)
 390 {
 391         struct usb_cpia *ucpia = (struct usb_cpia *) privdata;
 392         struct framebuf *mybuff;
 393
 394         if (!ucpia || !ucpia->present)
 395                 return -1;
 396
 397         if (ucpia->curbuff->status != FRAME_READY)
 398                 interruptible_sleep_on(&ucpia->wq_stream);
 399         else
 400                 DBG("Frame already waiting!\n");
 401
 402         mybuff = ucpia->curbuff;
 403
 404         if (!mybuff)
 405                 return -1;
 406
 407         if (mybuff->status != FRAME_READY || mybuff->length < 4) {
 408                 DBG("Something went wrong!\n");
 409                 return -1;
 410         }
 411
 412         memcpy(frame, mybuff->data, mybuff->length);
 413         mybuff->status = FRAME_EMPTY;
 414
 415 /*   DBG("read done, %d bytes, Header: %x/%x, Footer: %x%x%x%x\n",  */
 416 /*       mybuff->length, frame[0], frame[1], */
 417 /*       frame[mybuff->length-4], frame[mybuff->length-3],  */
 418 /*       frame[mybuff->length-2], frame[mybuff->length-1]); */
 419
 420         return mybuff->length;
 421 }
 422
 423 static void cpia_usb_free_resources(struct usb_cpia *ucpia, int try)
 424 {
 425         if (!ucpia->streaming)
 426                 return;
 427
 428         ucpia->streaming = 0;
 429
 430         /* Set packet size to 0 */
 431         if (try) {
 432                 int ret;
 433
 434                 ret = usb_set_interface(ucpia->dev, ucpia->iface, 0);
 435                 if (ret < 0) {
 436                         printk(KERN_ERR "usb_set_interface error (ret = %d)\n", ret);
 437                         return;
 438                 }
 439         }
 440
 441         /* Unschedule all of the iso td's */
 442         if (ucpia->sbuf[1].urb) {
 443                 usb_kill_urb(ucpia->sbuf[1].urb);
 444                 usb_free_urb(ucpia->sbuf[1].urb);
 445                 ucpia->sbuf[1].urb = NULL;
 446         }
 447
 448         if (ucpia->sbuf[1].data) {
 449                 kfree(ucpia->sbuf[1].data);
 450                 ucpia->sbuf[1].data = NULL;
 451         }
 452
 453         if (ucpia->sbuf[0].urb) {
 454                 usb_kill_urb(ucpia->sbuf[0].urb);
 455                 usb_free_urb(ucpia->sbuf[0].urb);
 456                 ucpia->sbuf[0].urb = NULL;
 457         }
 458
 459         if (ucpia->sbuf[0].data) {
 460                 kfree(ucpia->sbuf[0].data);
 461                 ucpia->sbuf[0].data = NULL;
 462         }
 463 }
 464
 465 static int cpia_usb_close(void *privdata)
 466 {
 467         struct usb_cpia *ucpia = (struct usb_cpia *) privdata;
 468
 469         if(!ucpia)
 470                 return -ENODEV;
 471
 472         ucpia->open = 0;
 473
 474         /* ucpia->present = 0 protects against trying to reset the
 475          * alt setting if camera is physically disconnected while open */
 476         cpia_usb_free_resources(ucpia, ucpia->present);
 477
 478         return 0;
 479 }
 480
 481 int cpia_usb_init(void)
 482 {
 483         /* return -ENODEV; */
 484         return 0;
 485 }
 486
 487 /* Probing and initializing */
 488
 489 static int cpia_probe(struct usb_interface *intf,
 490                       const struct usb_device_id *id)
 491 {
 492         struct usb_device *udev = interface_to_usbdev(intf);
 493         struct usb_host_interface *interface;
 494         struct usb_cpia *ucpia;
 495         struct cam_data *cam;
 496         int ret;
 497
 498         /* A multi-config CPiA camera? */
 499         if (udev->descriptor.bNumConfigurations != 1)
 500                 return -ENODEV;
 501
 502         interface = intf->cur_altsetting;
 503
 504         printk(KERN_INFO "USB CPiA camera found\n");
 505
 506         ucpia = kmalloc(sizeof(*ucpia), GFP_KERNEL);
 507         if (!ucpia) {
 508                 printk(KERN_ERR "couldn't kmalloc cpia struct\n");
 509                 return -ENOMEM;
 510         }
 511
 512         memset(ucpia, 0, sizeof(*ucpia));
 513
 514         ucpia->dev = udev;
 515         ucpia->iface = interface->desc.bInterfaceNumber;
 516         init_waitqueue_head(&ucpia->wq_stream);
 517
 518         ucpia->buffers[0] = vmalloc(sizeof(*ucpia->buffers[0]));
 519         if (!ucpia->buffers[0]) {
 520                 printk(KERN_ERR "couldn't vmalloc frame buffer 0\n");
 521                 goto fail_alloc_0;
 522         }
 523
 524         ucpia->buffers[1] = vmalloc(sizeof(*ucpia->buffers[1]));
 525         if (!ucpia->buffers[1]) {
 526                 printk(KERN_ERR "couldn't vmalloc frame buffer 1\n");
 527                 goto fail_alloc_1;
 528         }
 529
 530         ucpia->buffers[2] = vmalloc(sizeof(*ucpia->buffers[2]));
 531         if (!ucpia->buffers[2]) {
 532                 printk(KERN_ERR "couldn't vmalloc frame buffer 2\n");
 533                 goto fail_alloc_2;
 534         }
 535
 536         ucpia->buffers[0]->next = ucpia->buffers[1];
 537         ucpia->buffers[1]->next = ucpia->buffers[2];
 538         ucpia->buffers[2]->next = ucpia->buffers[0];
 539
 540         ret = usb_set_interface(udev, ucpia->iface, 0);
 541         if (ret < 0) {
 542                 printk(KERN_ERR "cpia_probe: usb_set_interface error (ret = %d)\n", ret);
 543                 /* goto fail_all; */
 544         }
 545
 546         /* Before register_camera, important */
 547         ucpia->present = 1;
 548
 549         cam = cpia_register_camera(&cpia_usb_ops, ucpia);
 550         if (!cam) {
 551                 LOG("failed to cpia_register_camera\n");
 552                 goto fail_all;
 553         }
 554
 555         spin_lock( &cam_list_lock_usb );
 556         list_add( &cam->cam_data_list, &cam_list );
 557         spin_unlock( &cam_list_lock_usb );
 558
 559         usb_set_intfdata(intf, cam);
 560         return 0;
 561
 562 fail_all:
 563         vfree(ucpia->buffers[2]);
 564         ucpia->buffers[2] = NULL;
 565 fail_alloc_2:
 566         vfree(ucpia->buffers[1]);
 567         ucpia->buffers[1] = NULL;
 568 fail_alloc_1:
 569         vfree(ucpia->buffers[0]);
 570         ucpia->buffers[0] = NULL;
 571 fail_alloc_0:
 572         kfree(ucpia);
 573         return -EIO;
 574 }
 575
 576 static void cpia_disconnect(struct usb_interface *intf);
 577
 578 static struct usb_device_id cpia_id_table [] = {
 579         { USB_DEVICE(0x0553, 0x0002) },
 580         { USB_DEVICE(0x0813, 0x0001) },
 581         { }                                     /* Terminating entry */
 582 };
 583
 584 MODULE_DEVICE_TABLE (usb, cpia_id_table);
 585 MODULE_LICENSE("GPL");
 586
 587
 588 static struct usb_driver cpia_driver = {
 589         .owner          = THIS_MODULE,
 590         .name           = "cpia",
 591         .probe          = cpia_probe,
 592         .disconnect     = cpia_disconnect,
 593         .id_table       = cpia_id_table,
 594 };
 595
 596 static void cpia_disconnect(struct usb_interface *intf)
 597 {
 598         struct cam_data *cam = usb_get_intfdata(intf);
 599         struct usb_cpia *ucpia;
 600         struct usb_device *udev;
 601
 602         usb_set_intfdata(intf, NULL);
 603         if (!cam)
 604                 return;
 605
 606         ucpia = (struct usb_cpia *) cam->lowlevel_data;
 607         spin_lock( &cam_list_lock_usb );
 608         list_del(&cam->cam_data_list);
 609         spin_unlock( &cam_list_lock_usb );
 610
 611         ucpia->present = 0;
 612
 613         cpia_unregister_camera(cam);
 614         if(ucpia->open)
 615                 cpia_usb_close(cam->lowlevel_data);
 616
 617         ucpia->curbuff->status = FRAME_ERROR;
 618
 619         if (waitqueue_active(&ucpia->wq_stream))
 620                 wake_up_interruptible(&ucpia->wq_stream);
 621
 622         udev = interface_to_usbdev(intf);
 623
 624         ucpia->curbuff = ucpia->workbuff = NULL;
 625
 626         if (ucpia->buffers[2]) {
 627                 vfree(ucpia->buffers[2]);
 628                 ucpia->buffers[2] = NULL;
 629         }
 630
 631         if (ucpia->buffers[1]) {
 632                 vfree(ucpia->buffers[1]);
 633                 ucpia->buffers[1] = NULL;
 634         }
 635
 636         if (ucpia->buffers[0]) {
 637                 vfree(ucpia->buffers[0]);
 638                 ucpia->buffers[0] = NULL;
 639         }
 640
 641         cam->lowlevel_data = NULL;
 642         kfree(ucpia);
 643 }
 644
 645 static int __init usb_cpia_init(void)
 646 {
 647         printk(KERN_INFO "%s v%d.%d.%d\n",ABOUT,
 648                CPIA_USB_MAJ_VER,CPIA_USB_MIN_VER,CPIA_USB_PATCH_VER);
 649
 650         spin_lock_init(&cam_list_lock_usb);
 651         return usb_register(&cpia_driver);
 652 }
 653
 654 static void __exit usb_cpia_cleanup(void)
 655 {
 656         usb_deregister(&cpia_driver);
 657 }
 658
 659
 660 module_init (usb_cpia_init);
 661 module_exit (usb_cpia_cleanup);
 662