drivers/usb/image/mdc800.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * copyright (C) 1999/2000 by Henning Zabel <henning@uni-paderborn.de>
   4  */
   5
   6
   7 /*
   8  *      USB-Kernel Driver for the Mustek MDC800 Digital Camera
   9  *      (c) 1999/2000 Henning Zabel <henning@uni-paderborn.de>
  10  *
  11  *
  12  * The driver brings the USB functions of the MDC800 to Linux.
  13  * To use the Camera you must support the USB Protocol of the camera
  14  * to the Kernel Node.
  15  * The Driver uses a misc device Node. Create it with :
  16  * mknod /dev/mustek c 180 32
  17  *
  18  * The driver supports only one camera.
  19  *
  20  * Fix: mdc800 used sleep_on and slept with io_lock held.
  21  * Converted sleep_on to waitqueues with schedule_timeout and made io_lock
  22  * a semaphore from a spinlock.
  23  * by Oliver Neukum <oliver@neukum.name>
  24  * (02/12/2001)
  25  *
  26  * Identify version on module load.
  27  * (08/04/2001) gb
  28  *
  29  * version 0.7.5
  30  * Fixed potential SMP races with Spinlocks.
  31  * Thanks to Oliver Neukum <oliver@neukum.name> who
  32  * noticed the race conditions.
  33  * (30/10/2000)
  34  *
  35  * Fixed: Setting urb->dev before submitting urb.
  36  * by Greg KH <greg@kroah.com>
  37  * (13/10/2000)
  38  *
  39  * version 0.7.3
  40  * bugfix : The mdc800->state field gets set to READY after the
  41  * the disconnect function sets it to NOT_CONNECTED. This makes the
  42  * driver running like the camera is connected and causes some
  43  * hang ups.
  44  *
  45  * version 0.7.1
  46  * MOD_INC and MOD_DEC are changed in usb_probe to prevent load/unload
  47  * problems when compiled as Module.
  48  * (04/04/2000)
  49  *
  50  * The mdc800 driver gets assigned the USB Minor 32-47. The Registration
  51  * was updated to use these values.
  52  * (26/03/2000)
  53  *
  54  * The Init und Exit Module Function are updated.
  55  * (01/03/2000)
  56  *
  57  * version 0.7.0
  58  * Rewrite of the driver : The driver now uses URB's. The old stuff
  59  * has been removed.
  60  *
  61  * version 0.6.0
  62  * Rewrite of this driver: The Emulation of the rs232 protocoll
  63  * has been removed from the driver. A special executeCommand function
  64  * for this driver is included to gphoto.
  65  * The driver supports two kind of communication to bulk endpoints.
  66  * Either with the dev->bus->ops->bulk... or with callback function.
  67  * (09/11/1999)
  68  *
  69  * version 0.5.0:
  70  * first Version that gets a version number. Most of the needed
  71  * functions work.
  72  * (20/10/1999)
  73  */
  74
  75 #include <linux/sched/signal.h>
  76 #include <linux/signal.h>
  77 #include <linux/spinlock.h>
  78 #include <linux/errno.h>
  79 #include <linux/random.h>
  80 #include <linux/poll.h>
  81 #include <linux/init.h>
  82 #include <linux/slab.h>
  83 #include <linux/module.h>
  84 #include <linux/wait.h>
  85 #include <linux/mutex.h>
  86
  87 #include <linux/usb.h>
  88 #include <linux/fs.h>
  89
  90 /*
  91  * Version Information
  92  */
  93 #define DRIVER_VERSION "v0.7.5 (30/10/2000)"
  94 #define DRIVER_AUTHOR "Henning Zabel <henning@uni-paderborn.de>"
  95 #define DRIVER_DESC "USB Driver for Mustek MDC800 Digital Camera"
  96
  97 /* Vendor and Product Information */
  98 #define MDC800_VENDOR_ID        0x055f
  99 #define MDC800_PRODUCT_ID       0xa800
 100
 101 /* Timeouts (msec) */
 102 #define TO_DOWNLOAD_GET_READY           1500
 103 #define TO_DOWNLOAD_GET_BUSY            1500
 104 #define TO_WRITE_GET_READY              1000
 105 #define TO_DEFAULT_COMMAND              5000
 106 #define TO_READ_FROM_IRQ                TO_DEFAULT_COMMAND
 107 #define TO_GET_READY                    TO_DEFAULT_COMMAND
 108
 109 /* Minor Number of the device (create with mknod /dev/mustek c 180 32) */
 110 #define MDC800_DEVICE_MINOR_BASE 32
 111
 112
 113 /**************************************************************************
 114         Data and structs
 115 ***************************************************************************/
 116
 117
 118 typedef enum {
 119         NOT_CONNECTED, READY, WORKING, DOWNLOAD
 120 } mdc800_state;
 121
 122
 123 /* Data for the driver */
 124 struct mdc800_data
 125 {
 126         struct usb_device *     dev;                    // Device Data
 127         mdc800_state            state;
 128
 129         unsigned int            endpoint [4];
 130
 131         struct urb *            irq_urb;
 132         wait_queue_head_t       irq_wait;
 133         int                     irq_woken;
 134         char*                   irq_urb_buffer;
 135
 136         int                     camera_busy;          // is camera busy ?
 137         int                     camera_request_ready; // Status to synchronize with irq
 138         char                    camera_response [8];  // last Bytes send after busy
 139
 140         struct urb *            write_urb;
 141         char*                   write_urb_buffer;
 142         wait_queue_head_t       write_wait;
 143         int                     written;
 144
 145
 146         struct urb *            download_urb;
 147         char*                   download_urb_buffer;
 148         wait_queue_head_t       download_wait;
 149         int                     downloaded;
 150         int                     download_left;          // Bytes left to download ?
 151
 152
 153         /* Device Data */
 154         char                    out [64];       // Answer Buffer
 155         int                     out_ptr;        // Index to the first not readen byte
 156         int                     out_count;      // Bytes in the buffer
 157
 158         int                     open;           // Camera device open ?
 159         struct mutex            io_lock;        // IO -lock
 160
 161         char                    in [8];         // Command Input Buffer
 162         int                     in_count;
 163
 164         int                     pic_index;      // Cache for the Imagesize (-1 for nothing cached )
 165         int                     pic_len;
 166         int                     minor;
 167 };
 168
 169
 170 /* Specification of the Endpoints */
 171 static struct usb_endpoint_descriptor mdc800_ed [4] =
 172 {
 173         {
 174                 .bLength =              0,
 175                 .bDescriptorType =      0,
 176                 .bEndpointAddress =     0x01,
 177                 .bmAttributes =         0x02,
 178                 .wMaxPacketSize =       cpu_to_le16(8),
 179                 .bInterval =            0,
 180                 .bRefresh =             0,
 181                 .bSynchAddress =        0,
 182         },
 183         {
 184                 .bLength =              0,
 185                 .bDescriptorType =      0,
 186                 .bEndpointAddress =     0x82,
 187                 .bmAttributes =         0x03,
 188                 .wMaxPacketSize =       cpu_to_le16(8),
 189                 .bInterval =            0,
 190                 .bRefresh =             0,
 191                 .bSynchAddress =        0,
 192         },
 193         {
 194                 .bLength =              0,
 195                 .bDescriptorType =      0,
 196                 .bEndpointAddress =     0x03,
 197                 .bmAttributes =         0x02,
 198                 .wMaxPacketSize =       cpu_to_le16(64),
 199                 .bInterval =            0,
 200                 .bRefresh =             0,
 201                 .bSynchAddress =        0,
 202         },
 203         {
 204                 .bLength =              0,
 205                 .bDescriptorType =      0,
 206                 .bEndpointAddress =     0x84,
 207                 .bmAttributes =         0x02,
 208                 .wMaxPacketSize =       cpu_to_le16(64),
 209                 .bInterval =            0,
 210                 .bRefresh =             0,
 211                 .bSynchAddress =        0,
 212         },
 213 };
 214
 215 /* The Variable used by the driver */
 216 static struct mdc800_data* mdc800;
 217
 218
 219 /***************************************************************************
 220         The USB Part of the driver
 221 ****************************************************************************/
 222
 223 static int mdc800_endpoint_equals (struct usb_endpoint_descriptor *a,struct usb_endpoint_descriptor *b)
 224 {
 225         return (
 226                    ( a->bEndpointAddress == b->bEndpointAddress )
 227                 && ( a->bmAttributes     == b->bmAttributes     )
 228                 && ( a->wMaxPacketSize   == b->wMaxPacketSize   )
 229         );
 230 }
 231
 232
 233 /*
 234  * Checks whether the camera responds busy
 235  */
 236 static int mdc800_isBusy (char* ch)
 237 {
 238         int i=0;
 239         while (i<8)
 240         {
 241                 if (ch [i] != (char)0x99)
 242                         return 0;
 243                 i++;
 244         }
 245         return 1;
 246 }
 247
 248
 249 /*
 250  * Checks whether the Camera is ready
 251  */
 252 static int mdc800_isReady (char *ch)
 253 {
 254         int i=0;
 255         while (i<8)
 256         {
 257                 if (ch [i] != (char)0xbb)
 258                         return 0;
 259                 i++;
 260         }
 261         return 1;
 262 }
 263
 264
 265
 266 /*
 267  * USB IRQ Handler for InputLine
 268  */
 269 static void mdc800_usb_irq (struct urb *urb)
 270 {
 271         int data_received=0, wake_up;
 272         unsigned char* b=urb->transfer_buffer;
 273         struct mdc800_data* mdc800=urb->context;
 274         struct device *dev = &mdc800->dev->dev;
 275         int status = urb->status;
 276
 277         if (status >= 0) {
 278                 if (mdc800_isBusy (b))
 279                 {
 280                         if (!mdc800->camera_busy)
 281                         {
 282                                 mdc800->camera_busy=1;
 283                                 dev_dbg(dev, "gets busy\n");
 284                         }
 285                 }
 286                 else
 287                 {
 288                         if (mdc800->camera_busy && mdc800_isReady (b))
 289                         {
 290                                 mdc800->camera_busy=0;
 291                                 dev_dbg(dev, "gets ready\n");
 292                         }
 293                 }
 294                 if (!(mdc800_isBusy (b) || mdc800_isReady (b)))
 295                 {
 296                         /* Store Data in camera_answer field */
 297                         dev_dbg(dev, "%i %i %i %i %i %i %i %i \n",b[0],b[1],b[2],b[3],b[4],b[5],b[6],b[7]);
 298
 299                         memcpy (mdc800->camera_response,b,8);
 300                         data_received=1;
 301                 }
 302         }
 303         wake_up= ( mdc800->camera_request_ready > 0 )
 304                 &&
 305                 (
 306                         ((mdc800->camera_request_ready == 1) && (!mdc800->camera_busy))
 307                 ||
 308                         ((mdc800->camera_request_ready == 2) && data_received)
 309                 ||
 310                         ((mdc800->camera_request_ready == 3) && (mdc800->camera_busy))
 311                 ||
 312                         (status < 0)
 313                 );
 314
 315         if (wake_up)
 316         {
 317                 mdc800->camera_request_ready=0;
 318                 mdc800->irq_woken=1;
 319                 wake_up (&mdc800->irq_wait);
 320         }
 321 }
 322
 323
 324 /*
 325  * Waits a while until the irq responds that camera is ready
 326  *
 327  *  mode : 0: Wait for camera gets ready
 328  *         1: Wait for receiving data
 329  *         2: Wait for camera gets busy
 330  *
 331  * msec: Time to wait
 332  */
 333 static int mdc800_usb_waitForIRQ (int mode, int msec)
 334 {
 335         mdc800->camera_request_ready=1+mode;
 336
 337         wait_event_timeout(mdc800->irq_wait, mdc800->irq_woken,
 338                            msecs_to_jiffies(msec));
 339         mdc800->irq_woken = 0;
 340
 341         if (mdc800->camera_request_ready>0)
 342         {
 343                 mdc800->camera_request_ready=0;
 344                 dev_err(&mdc800->dev->dev, "timeout waiting for camera.\n");
 345                 return -1;
 346         }
 347
 348         if (mdc800->state == NOT_CONNECTED)
 349         {
 350                 printk(KERN_WARNING "mdc800: Camera gets disconnected "
 351                        "during waiting for irq.\n");
 352                 mdc800->camera_request_ready=0;
 353                 return -2;
 354         }
 355
 356         return 0;
 357 }
 358
 359
 360 /*
 361  * The write_urb callback function
 362  */
 363 static void mdc800_usb_write_notify (struct urb *urb)
 364 {
 365         struct mdc800_data* mdc800=urb->context;
 366         int status = urb->status;
 367
 368         if (status != 0)
 369                 dev_err(&mdc800->dev->dev,
 370                         "writing command fails (status=%i)\n", status);
 371         else
 372                 mdc800->state=READY;
 373         mdc800->written = 1;
 374         wake_up (&mdc800->write_wait);
 375 }
 376
 377
 378 /*
 379  * The download_urb callback function
 380  */
 381 static void mdc800_usb_download_notify (struct urb *urb)
 382 {
 383         struct mdc800_data* mdc800=urb->context;
 384         int status = urb->status;
 385
 386         if (status == 0) {
 387                 /* Fill output buffer with these data */
 388                 memcpy (mdc800->out,  urb->transfer_buffer, 64);
 389                 mdc800->out_count=64;
 390                 mdc800->out_ptr=0;
 391                 mdc800->download_left-=64;
 392                 if (mdc800->download_left == 0)
 393                 {
 394                         mdc800->state=READY;
 395                 }
 396         } else {
 397                 dev_err(&mdc800->dev->dev,
 398                         "request bytes fails (status:%i)\n", status);
 399         }
 400         mdc800->downloaded = 1;
 401         wake_up (&mdc800->download_wait);
 402 }
 403
 404
 405 /***************************************************************************
 406         Probing for the Camera
 407  ***************************************************************************/
 408
 409 static struct usb_driver mdc800_usb_driver;
 410 static const struct file_operations mdc800_device_ops;
 411 static struct usb_class_driver mdc800_class = {
 412         .name =         "mdc800%d",
 413         .fops =         &mdc800_device_ops,
 414         .minor_base =   MDC800_DEVICE_MINOR_BASE,
 415 };
 416
 417
 418 /*
 419  * Callback to search the Mustek MDC800 on the USB Bus
 420  */
 421 static int mdc800_usb_probe (struct usb_interface *intf,
 422                                const struct usb_device_id *id)
 423 {
 424         int i,j;
 425         struct usb_host_interface *intf_desc;
 426         struct usb_device *dev = interface_to_usbdev (intf);
 427         int irq_interval=0;
 428         int retval;
 429
 430         dev_dbg(&intf->dev, "(%s) called.\n", __func__);
 431
 432
 433         if (mdc800->dev != NULL)
 434         {
 435                 dev_warn(&intf->dev, "only one Mustek MDC800 is supported.\n");
 436                 return -ENODEV;
 437         }
 438
 439         if (dev->descriptor.bNumConfigurations != 1)
 440         {
 441                 dev_err(&intf->dev,
 442                         "probe fails -> wrong Number of Configuration\n");
 443                 return -ENODEV;
 444         }
 445         intf_desc = intf->cur_altsetting;
 446
 447         if (
 448                         ( intf_desc->desc.bInterfaceClass != 0xff )
 449                 ||      ( intf_desc->desc.bInterfaceSubClass != 0 )
 450                 || ( intf_desc->desc.bInterfaceProtocol != 0 )
 451                 || ( intf_desc->desc.bNumEndpoints != 4)
 452         )
 453         {
 454                 dev_err(&intf->dev, "probe fails -> wrong Interface\n");
 455                 return -ENODEV;
 456         }
 457
 458         /* Check the Endpoints */
 459         for (i=0; i<4; i++)
 460         {
 461                 mdc800->endpoint[i]=-1;
 462                 for (j=0; j<4; j++)
 463                 {
 464                         if (mdc800_endpoint_equals (&intf_desc->endpoint [j].desc,&mdc800_ed [i]))
 465                         {
 466                                 mdc800->endpoint[i]=intf_desc->endpoint [j].desc.bEndpointAddress ;
 467                                 if (i==1)
 468                                 {
 469                                         irq_interval=intf_desc->endpoint [j].desc.bInterval;
 470                                 }
 471                         }
 472                 }
 473                 if (mdc800->endpoint[i] == -1)
 474                 {
 475                         dev_err(&intf->dev, "probe fails -> Wrong Endpoints.\n");
 476                         return -ENODEV;
 477                 }
 478         }
 479
 480
 481         dev_info(&intf->dev, "Found Mustek MDC800 on USB.\n");
 482
 483         mutex_lock(&mdc800->io_lock);
 484
 485         retval = usb_register_dev(intf, &mdc800_class);
 486         if (retval) {
 487                 dev_err(&intf->dev, "Not able to get a minor for this device.\n");
 488                 mutex_unlock(&mdc800->io_lock);
 489                 return -ENODEV;
 490         }
 491
 492         mdc800->dev=dev;
 493         mdc800->open=0;
 494
 495         /* Setup URB Structs */
 496         usb_fill_int_urb (
 497                 mdc800->irq_urb,
 498                 mdc800->dev,
 499                 usb_rcvintpipe (mdc800->dev,mdc800->endpoint [1]),
 500                 mdc800->irq_urb_buffer,
 501                 8,
 502                 mdc800_usb_irq,
 503                 mdc800,
 504                 irq_interval
 505         );
 506
 507         usb_fill_bulk_urb (
 508                 mdc800->write_urb,
 509                 mdc800->dev,
 510                 usb_sndbulkpipe (mdc800->dev, mdc800->endpoint[0]),
 511                 mdc800->write_urb_buffer,
 512                 8,
 513                 mdc800_usb_write_notify,
 514                 mdc800
 515         );
 516
 517         usb_fill_bulk_urb (
 518                 mdc800->download_urb,
 519                 mdc800->dev,
 520                 usb_rcvbulkpipe (mdc800->dev, mdc800->endpoint [3]),
 521                 mdc800->download_urb_buffer,
 522                 64,
 523                 mdc800_usb_download_notify,
 524                 mdc800
 525         );
 526
 527         mdc800->state=READY;
 528
 529         mutex_unlock(&mdc800->io_lock);
 530
 531         usb_set_intfdata(intf, mdc800);
 532         return 0;
 533 }
 534
 535
 536 /*
 537  * Disconnect USB device (maybe the MDC800)
 538  */
 539 static void mdc800_usb_disconnect (struct usb_interface *intf)
 540 {
 541         struct mdc800_data* mdc800 = usb_get_intfdata(intf);
 542
 543         dev_dbg(&intf->dev, "(%s) called\n", __func__);
 544
 545         if (mdc800) {
 546                 if (mdc800->state == NOT_CONNECTED)
 547                         return;
 548
 549                 usb_deregister_dev(intf, &mdc800_class);
 550
 551                 /* must be under lock to make sure no URB
 552                    is submitted after usb_kill_urb() */
 553                 mutex_lock(&mdc800->io_lock);
 554                 mdc800->state=NOT_CONNECTED;
 555
 556                 usb_kill_urb(mdc800->irq_urb);
 557                 usb_kill_urb(mdc800->write_urb);
 558                 usb_kill_urb(mdc800->download_urb);
 559                 mutex_unlock(&mdc800->io_lock);
 560
 561                 mdc800->dev = NULL;
 562                 usb_set_intfdata(intf, NULL);
 563         }
 564         dev_info(&intf->dev, "Mustek MDC800 disconnected from USB.\n");
 565 }
 566
 567
 568 /***************************************************************************
 569         The Misc device Part (file_operations)
 570 ****************************************************************************/
 571
 572 /*
 573  * This Function calc the Answersize for a command.
 574  */
 575 static int mdc800_getAnswerSize (char command)
 576 {
 577         switch ((unsigned char) command)
 578         {
 579                 case 0x2a:
 580                 case 0x49:
 581                 case 0x51:
 582                 case 0x0d:
 583                 case 0x20:
 584                 case 0x07:
 585                 case 0x01:
 586                 case 0x25:
 587                 case 0x00:
 588                         return 8;
 589
 590                 case 0x05:
 591                 case 0x3e:
 592                         return mdc800->pic_len;
 593
 594                 case 0x09:
 595                         return 4096;
 596
 597                 default:
 598                         return 0;
 599         }
 600 }
 601
 602
 603 /*
 604  * Init the device: (1) alloc mem (2) Increase MOD Count ..
 605  */
 606 static int mdc800_device_open (struct inode* inode, struct file *file)
 607 {
 608         int retval=0;
 609         int errn=0;
 610
 611         mutex_lock(&mdc800->io_lock);
 612
 613         if (mdc800->state == NOT_CONNECTED)
 614         {
 615                 errn=-EBUSY;
 616                 goto error_out;
 617         }
 618         if (mdc800->open)
 619         {
 620                 errn=-EBUSY;
 621                 goto error_out;
 622         }
 623
 624         mdc800->in_count=0;
 625         mdc800->out_count=0;
 626         mdc800->out_ptr=0;
 627         mdc800->pic_index=0;
 628         mdc800->pic_len=-1;
 629         mdc800->download_left=0;
 630
 631         mdc800->camera_busy=0;
 632         mdc800->camera_request_ready=0;
 633
 634         retval=0;
 635         mdc800->irq_urb->dev = mdc800->dev;
 636         retval = usb_submit_urb (mdc800->irq_urb, GFP_KERNEL);
 637         if (retval) {
 638                 dev_err(&mdc800->dev->dev,
 639                         "request USB irq fails (submit_retval=%i).\n", retval);
 640                 errn = -EIO;
 641                 goto error_out;
 642         }
 643
 644         mdc800->open=1;
 645         dev_dbg(&mdc800->dev->dev, "Mustek MDC800 device opened.\n");
 646
 647 error_out:
 648         mutex_unlock(&mdc800->io_lock);
 649         return errn;
 650 }
 651
 652
 653 /*
 654  * Close the Camera and release Memory
 655  */
 656 static int mdc800_device_release (struct inode* inode, struct file *file)
 657 {
 658         int retval=0;
 659
 660         mutex_lock(&mdc800->io_lock);
 661         if (mdc800->open && (mdc800->state != NOT_CONNECTED))
 662         {
 663                 usb_kill_urb(mdc800->irq_urb);
 664                 usb_kill_urb(mdc800->write_urb);
 665                 usb_kill_urb(mdc800->download_urb);
 666                 mdc800->open=0;
 667         }
 668         else
 669         {
 670                 retval=-EIO;
 671         }
 672
 673         mutex_unlock(&mdc800->io_lock);
 674         return retval;
 675 }
 676
 677
 678 /*
 679  * The Device read callback Function
 680  */
 681 static ssize_t mdc800_device_read (struct file *file, char __user *buf, size_t len, loff_t *pos)
 682 {
 683         size_t left=len, sts=len; /* single transfer size */
 684         char __user *ptr = buf;
 685         int retval;
 686
 687         mutex_lock(&mdc800->io_lock);
 688         if (mdc800->state == NOT_CONNECTED)
 689         {
 690                 mutex_unlock(&mdc800->io_lock);
 691                 return -EBUSY;
 692         }
 693         if (mdc800->state == WORKING)
 694         {
 695                 printk(KERN_WARNING "mdc800: Illegal State \"working\""
 696                        "reached during read ?!\n");
 697                 mutex_unlock(&mdc800->io_lock);
 698                 return -EBUSY;
 699         }
 700         if (!mdc800->open)
 701         {
 702                 mutex_unlock(&mdc800->io_lock);
 703                 return -EBUSY;
 704         }
 705
 706         while (left)
 707         {
 708                 if (signal_pending (current))
 709                 {
 710                         mutex_unlock(&mdc800->io_lock);
 711                         return -EINTR;
 712                 }
 713
 714                 sts=left > (mdc800->out_count-mdc800->out_ptr)?mdc800->out_count-mdc800->out_ptr:left;
 715
 716                 if (sts <= 0)
 717                 {
 718                         /* Too less Data in buffer */
 719                         if (mdc800->state == DOWNLOAD)
 720                         {
 721                                 mdc800->out_count=0;
 722                                 mdc800->out_ptr=0;
 723
 724                                 /* Download -> Request new bytes */
 725                                 mdc800->download_urb->dev = mdc800->dev;
 726                                 retval = usb_submit_urb (mdc800->download_urb, GFP_KERNEL);
 727                                 if (retval) {
 728                                         dev_err(&mdc800->dev->dev,
 729                                                 "Can't submit download urb "
 730                                                 "(retval=%i)\n", retval);
 731                                         mutex_unlock(&mdc800->io_lock);
 732                                         return len-left;
 733                                 }
 734                                 wait_event_timeout(mdc800->download_wait,
 735                                      mdc800->downloaded,
 736                                      msecs_to_jiffies(TO_DOWNLOAD_GET_READY));
 737                                 mdc800->downloaded = 0;
 738                                 if (mdc800->download_urb->status != 0)
 739                                 {
 740                                         dev_err(&mdc800->dev->dev,
 741                                                 "request download-bytes fails "
 742                                                 "(status=%i)\n",
 743                                                 mdc800->download_urb->status);
 744                                         mutex_unlock(&mdc800->io_lock);
 745                                         return len-left;
 746                                 }
 747                         }
 748                         else
 749                         {
 750                                 /* No more bytes -> that's an error*/
 751                                 mutex_unlock(&mdc800->io_lock);
 752                                 return -EIO;
 753                         }
 754                 }
 755                 else
 756                 {
 757                         /* Copy Bytes */
 758                         if (copy_to_user(ptr, &mdc800->out [mdc800->out_ptr],
 759                                                 sts)) {
 760                                 mutex_unlock(&mdc800->io_lock);
 761                                 return -EFAULT;
 762                         }
 763                         ptr+=sts;
 764                         left-=sts;
 765                         mdc800->out_ptr+=sts;
 766                 }
 767         }
 768
 769         mutex_unlock(&mdc800->io_lock);
 770         return len-left;
 771 }
 772
 773
 774 /*
 775  * The Device write callback Function
 776  * If a 8Byte Command is received, it will be send to the camera.
 777  * After this the driver initiates the request for the answer or
 778  * just waits until the camera becomes ready.
 779  */
 780 static ssize_t mdc800_device_write (struct file *file, const char __user *buf, size_t len, loff_t *pos)
 781 {
 782         size_t i=0;
 783         int retval;
 784
 785         mutex_lock(&mdc800->io_lock);
 786         if (mdc800->state != READY)
 787         {
 788                 mutex_unlock(&mdc800->io_lock);
 789                 return -EBUSY;
 790         }
 791         if (!mdc800->open )
 792         {
 793                 mutex_unlock(&mdc800->io_lock);
 794                 return -EBUSY;
 795         }
 796
 797         while (i<len)
 798         {
 799                 unsigned char c;
 800                 if (signal_pending (current))
 801                 {
 802                         mutex_unlock(&mdc800->io_lock);
 803                         return -EINTR;
 804                 }
 805
 806                 if(get_user(c, buf+i))
 807                 {
 808                         mutex_unlock(&mdc800->io_lock);
 809                         return -EFAULT;
 810                 }
 811
 812                 /* check for command start */
 813                 if (c == 0x55)
 814                 {
 815                         mdc800->in_count=0;
 816                         mdc800->out_count=0;
 817                         mdc800->out_ptr=0;
 818                         mdc800->download_left=0;
 819                 }
 820
 821                 /* save command byte */
 822                 if (mdc800->in_count < 8)
 823                 {
 824                         mdc800->in[mdc800->in_count] = c;
 825                         mdc800->in_count++;
 826                 }
 827                 else
 828                 {
 829                         mutex_unlock(&mdc800->io_lock);
 830                         return -EIO;
 831                 }
 832
 833                 /* Command Buffer full ? -> send it to camera */
 834                 if (mdc800->in_count == 8)
 835                 {
 836                         int answersize;
 837
 838                         if (mdc800_usb_waitForIRQ (0,TO_GET_READY))
 839                         {
 840                                 dev_err(&mdc800->dev->dev,
 841                                         "Camera didn't get ready.\n");
 842                                 mutex_unlock(&mdc800->io_lock);
 843                                 return -EIO;
 844                         }
 845
 846                         answersize=mdc800_getAnswerSize (mdc800->in[1]);
 847
 848                         mdc800->state=WORKING;
 849                         memcpy (mdc800->write_urb->transfer_buffer, mdc800->in,8);
 850                         mdc800->write_urb->dev = mdc800->dev;
 851                         retval = usb_submit_urb (mdc800->write_urb, GFP_KERNEL);
 852                         if (retval) {
 853                                 dev_err(&mdc800->dev->dev,
 854                                         "submitting write urb fails "
 855                                         "(retval=%i)\n", retval);
 856                                 mutex_unlock(&mdc800->io_lock);
 857                                 return -EIO;
 858                         }
 859                         wait_event_timeout(mdc800->write_wait, mdc800->written,
 860                                         msecs_to_jiffies(TO_WRITE_GET_READY));
 861                         mdc800->written = 0;
 862                         if (mdc800->state == WORKING)
 863                         {
 864                                 usb_kill_urb(mdc800->write_urb);
 865                                 mutex_unlock(&mdc800->io_lock);
 866                                 return -EIO;
 867                         }
 868
 869                         switch ((unsigned char) mdc800->in[1])
 870                         {
 871                                 case 0x05: /* Download Image */
 872                                 case 0x3e: /* Take shot in Fine Mode (WCam Mode) */
 873                                         if (mdc800->pic_len < 0)
 874                                         {
 875                                                 dev_err(&mdc800->dev->dev,
 876                                                         "call 0x07 before "
 877                                                         "0x05,0x3e\n");
 878                                                 mdc800->state=READY;
 879                                                 mutex_unlock(&mdc800->io_lock);
 880                                                 return -EIO;
 881                                         }
 882                                         mdc800->pic_len=-1;
 883                                         fallthrough;
 884
 885                                 case 0x09: /* Download Thumbnail */
 886                                         mdc800->download_left=answersize+64;
 887                                         mdc800->state=DOWNLOAD;
 888                                         mdc800_usb_waitForIRQ (0,TO_DOWNLOAD_GET_BUSY);
 889                                         break;
 890
 891
 892                                 default:
 893                                         if (answersize)
 894                                         {
 895
 896                                                 if (mdc800_usb_waitForIRQ (1,TO_READ_FROM_IRQ))
 897                                                 {
 898                                                         dev_err(&mdc800->dev->dev, "requesting answer from irq fails\n");
 899                                                         mutex_unlock(&mdc800->io_lock);
 900                                                         return -EIO;
 901                                                 }
 902
 903                                                 /* Write dummy data, (this is ugly but part of the USB Protocol */
 904                                                 /* if you use endpoint 1 as bulk and not as irq) */
 905                                                 memcpy (mdc800->out, mdc800->camera_response,8);
 906
 907                                                 /* This is the interpreted answer */
 908                                                 memcpy (&mdc800->out[8], mdc800->camera_response,8);
 909
 910                                                 mdc800->out_ptr=0;
 911                                                 mdc800->out_count=16;
 912
 913                                                 /* Cache the Imagesize, if command was getImageSize */
 914                                                 if (mdc800->in [1] == (char) 0x07)
 915                                                 {
 916                                                         mdc800->pic_len=(int) 65536*(unsigned char) mdc800->camera_response[0]+256*(unsigned char) mdc800->camera_response[1]+(unsigned char) mdc800->camera_response[2];
 917
 918                                                         dev_dbg(&mdc800->dev->dev, "cached imagesize = %i\n", mdc800->pic_len);
 919                                                 }
 920
 921                                         }
 922                                         else
 923                                         {
 924                                                 if (mdc800_usb_waitForIRQ (0,TO_DEFAULT_COMMAND))
 925                                                 {
 926                                                         dev_err(&mdc800->dev->dev, "Command Timeout.\n");
 927                                                         mutex_unlock(&mdc800->io_lock);
 928                                                         return -EIO;
 929                                                 }
 930                                         }
 931                                         mdc800->state=READY;
 932                                         break;
 933                         }
 934                 }
 935                 i++;
 936         }
 937         mutex_unlock(&mdc800->io_lock);
 938         return i;
 939 }
 940
 941
 942 /***************************************************************************
 943         Init and Cleanup this driver (Structs and types)
 944 ****************************************************************************/
 945
 946 /* File Operations of this drivers */
 947 static const struct file_operations mdc800_device_ops =
 948 {
 949         .owner =        THIS_MODULE,
 950         .read =         mdc800_device_read,
 951         .write =        mdc800_device_write,
 952         .open =         mdc800_device_open,
 953         .release =      mdc800_device_release,
 954         .llseek =       noop_llseek,
 955 };
 956
 957
 958
 959 static const struct usb_device_id mdc800_table[] = {
 960         { USB_DEVICE(MDC800_VENDOR_ID, MDC800_PRODUCT_ID) },
 961         { }                                             /* Terminating entry */
 962 };
 963
 964 MODULE_DEVICE_TABLE (usb, mdc800_table);
 965 /*
 966  * USB Driver Struct for this device
 967  */
 968 static struct usb_driver mdc800_usb_driver =
 969 {
 970         .name =         "mdc800",
 971         .probe =        mdc800_usb_probe,
 972         .disconnect =   mdc800_usb_disconnect,
 973         .id_table =     mdc800_table
 974 };
 975
 976
 977
 978 /************************************************************************
 979         Init and Cleanup this driver (Main Functions)
 980 *************************************************************************/
 981
 982 static int __init usb_mdc800_init (void)
 983 {
 984         int retval = -ENODEV;
 985         /* Allocate Memory */
 986         mdc800=kzalloc (sizeof (struct mdc800_data), GFP_KERNEL);
 987         if (!mdc800)
 988                 goto cleanup_on_fail;
 989
 990         mdc800->dev = NULL;
 991         mdc800->state=NOT_CONNECTED;
 992         mutex_init (&mdc800->io_lock);
 993
 994         init_waitqueue_head (&mdc800->irq_wait);
 995         init_waitqueue_head (&mdc800->write_wait);
 996         init_waitqueue_head (&mdc800->download_wait);
 997
 998         mdc800->irq_woken = 0;
 999         mdc800->downloaded = 0;
1000         mdc800->written = 0;
1001
1002         mdc800->irq_urb_buffer=kmalloc (8, GFP_KERNEL);
1003         if (!mdc800->irq_urb_buffer)
1004                 goto cleanup_on_fail;
1005         mdc800->write_urb_buffer=kmalloc (8, GFP_KERNEL);
1006         if (!mdc800->write_urb_buffer)
1007                 goto cleanup_on_fail;
1008         mdc800->download_urb_buffer=kmalloc (64, GFP_KERNEL);
1009         if (!mdc800->download_urb_buffer)
1010                 goto cleanup_on_fail;
1011
1012         mdc800->irq_urb=usb_alloc_urb (0, GFP_KERNEL);
1013         if (!mdc800->irq_urb)
1014                 goto cleanup_on_fail;
1015         mdc800->download_urb=usb_alloc_urb (0, GFP_KERNEL);
1016         if (!mdc800->download_urb)
1017                 goto cleanup_on_fail;
1018         mdc800->write_urb=usb_alloc_urb (0, GFP_KERNEL);
1019         if (!mdc800->write_urb)
1020                 goto cleanup_on_fail;
1021
1022         /* Register the driver */
1023         retval = usb_register(&mdc800_usb_driver);
1024         if (retval)
1025                 goto cleanup_on_fail;
1026
1027         printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
1028                DRIVER_DESC "\n");
1029
1030         return 0;
1031
1032         /* Clean driver up, when something fails */
1033
1034 cleanup_on_fail:
1035
1036         if (mdc800 != NULL)
1037         {
1038                 printk(KERN_ERR "mdc800: can't alloc memory!\n");
1039
1040                 kfree(mdc800->download_urb_buffer);
1041                 kfree(mdc800->write_urb_buffer);
1042                 kfree(mdc800->irq_urb_buffer);
1043
1044                 usb_free_urb(mdc800->write_urb);
1045                 usb_free_urb(mdc800->download_urb);
1046                 usb_free_urb(mdc800->irq_urb);
1047
1048                 kfree (mdc800);
1049         }
1050         mdc800 = NULL;
1051         return retval;
1052 }
1053
1054
1055 static void __exit usb_mdc800_cleanup (void)
1056 {
1057         usb_deregister (&mdc800_usb_driver);
1058
1059         usb_free_urb (mdc800->irq_urb);
1060         usb_free_urb (mdc800->download_urb);
1061         usb_free_urb (mdc800->write_urb);
1062
1063         kfree (mdc800->irq_urb_buffer);
1064         kfree (mdc800->write_urb_buffer);
1065         kfree (mdc800->download_urb_buffer);
1066
1067         kfree (mdc800);
1068         mdc800 = NULL;
1069 }
1070
1071 module_init (usb_mdc800_init);
1072 module_exit (usb_mdc800_cleanup);
1073
1074 MODULE_AUTHOR( DRIVER_AUTHOR );
1075 MODULE_DESCRIPTION( DRIVER_DESC );
1076 MODULE_LICENSE("GPL");
1077