git.oblomov.eu Git - linux-2.6/blob - drivers/usb/misc/ldusb.c

   1 /**
   2  * Generic USB driver for report based interrupt in/out devices
   3  * like LD Didactic's USB devices. LD Didactic's USB devices are
   4  * HID devices which do not use HID report definitons (they use
   5  * raw interrupt in and our reports only for communication).
   6  *
   7  * This driver uses a ring buffer for time critical reading of
   8  * interrupt in reports and provides read and write methods for
   9  * raw interrupt reports (similar to the Windows HID driver).
  10  * Devices based on the book USB COMPLETE by Jan Axelson may need
  11  * such a compatibility to the Windows HID driver.
  12  *
  13  * Copyright (C) 2005 Michael Hund <mhund@ld-didactic.de>
  14  *
  15  *      This program is free software; you can redistribute it and/or
  16  *      modify it under the terms of the GNU General Public License as
  17  *      published by the Free Software Foundation; either version 2 of
  18  *      the License, or (at your option) any later version.
  19  *
  20  * Derived from Lego USB Tower driver
  21  * Copyright (C) 2003 David Glance <advidgsf@sourceforge.net>
  22  *               2001-2004 Juergen Stuber <starblue@users.sourceforge.net>
  23  *
  24  * V0.1  (mh) Initial version
  25  * V0.11 (mh) Added raw support for HID 1.0 devices (no interrupt out endpoint)
  26  * V0.12 (mh) Added kmalloc check for string buffer
  27  * V0.13 (mh) Added support for LD X-Ray and Machine Test System
  28  */
  29
  30 #include <linux/kernel.h>
  31 #include <linux/errno.h>
  32 #include <linux/init.h>
  33 #include <linux/slab.h>
  34 #include <linux/module.h>
  35 #include <linux/mutex.h>
  36
  37 #include <asm/uaccess.h>
  38 #include <linux/input.h>
  39 #include <linux/usb.h>
  40 #include <linux/poll.h>
  41
  42 /* Define these values to match your devices */
  43 #define USB_VENDOR_ID_LD                0x0f11  /* USB Vendor ID of LD Didactic GmbH */
  44 #define USB_DEVICE_ID_LD_CASSY          0x1000  /* USB Product ID of CASSY-S */
  45 #define USB_DEVICE_ID_LD_POCKETCASSY    0x1010  /* USB Product ID of Pocket-CASSY */
  46 #define USB_DEVICE_ID_LD_MOBILECASSY    0x1020  /* USB Product ID of Mobile-CASSY */
  47 #define USB_DEVICE_ID_LD_JWM            0x1080  /* USB Product ID of Joule and Wattmeter */
  48 #define USB_DEVICE_ID_LD_DMMP           0x1081  /* USB Product ID of Digital Multimeter P (reserved) */
  49 #define USB_DEVICE_ID_LD_UMIP           0x1090  /* USB Product ID of UMI P */
  50 #define USB_DEVICE_ID_LD_XRAY1          0x1100  /* USB Product ID of X-Ray Apparatus */
  51 #define USB_DEVICE_ID_LD_XRAY2          0x1101  /* USB Product ID of X-Ray Apparatus */
  52 #define USB_DEVICE_ID_LD_VIDEOCOM       0x1200  /* USB Product ID of VideoCom */
  53 #define USB_DEVICE_ID_LD_COM3LAB        0x2000  /* USB Product ID of COM3LAB */
  54 #define USB_DEVICE_ID_LD_TELEPORT       0x2010  /* USB Product ID of Terminal Adapter */
  55 #define USB_DEVICE_ID_LD_NETWORKANALYSER 0x2020 /* USB Product ID of Network Analyser */
  56 #define USB_DEVICE_ID_LD_POWERCONTROL   0x2030  /* USB Product ID of Converter Control Unit */
  57 #define USB_DEVICE_ID_LD_MACHINETEST    0x2040  /* USB Product ID of Machine Test System */
  58
  59 #define USB_VENDOR_ID_VERNIER           0x08f7
  60 #define USB_DEVICE_ID_VERNIER_LABPRO    0x0001
  61 #define USB_DEVICE_ID_VERNIER_GOTEMP    0x0002
  62 #define USB_DEVICE_ID_VERNIER_SKIP      0x0003
  63 #define USB_DEVICE_ID_VERNIER_CYCLOPS   0x0004
  64
  65 #define USB_VENDOR_ID_MICROCHIP         0x04d8
  66 #define USB_DEVICE_ID_PICDEM            0x000c
  67
  68 #ifdef CONFIG_USB_DYNAMIC_MINORS
  69 #define USB_LD_MINOR_BASE       0
  70 #else
  71 #define USB_LD_MINOR_BASE       176
  72 #endif
  73
  74 /* table of devices that work with this driver */
  75 static struct usb_device_id ld_usb_table [] = {
  76         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY) },
  77         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY) },
  78         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY) },
  79         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_JWM) },
  80         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_DMMP) },
  81         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIP) },
  82         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY1) },
  83         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY2) },
  84         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_VIDEOCOM) },
  85         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_COM3LAB) },
  86         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_TELEPORT) },
  87         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_NETWORKANALYSER) },
  88         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POWERCONTROL) },
  89         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MACHINETEST) },
  90         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_LABPRO) },
  91         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_GOTEMP) },
  92         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_SKIP) },
  93         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_CYCLOPS) },
  94         { USB_DEVICE(USB_VENDOR_ID_MICROCHIP, USB_DEVICE_ID_PICDEM) },
  95         { }                                     /* Terminating entry */
  96 };
  97 MODULE_DEVICE_TABLE(usb, ld_usb_table);
  98 MODULE_VERSION("V0.13");
  99 MODULE_AUTHOR("Michael Hund <mhund@ld-didactic.de>");
 100 MODULE_DESCRIPTION("LD USB Driver");
 101 MODULE_LICENSE("GPL");
 102 MODULE_SUPPORTED_DEVICE("LD USB Devices");
 103
 104 #ifdef CONFIG_USB_DEBUG
 105         static int debug = 1;
 106 #else
 107         static int debug = 0;
 108 #endif
 109
 110 /* Use our own dbg macro */
 111 #define dbg_info(dev, format, arg...) do { if (debug) dev_info(dev , format , ## arg); } while (0)
 112
 113 /* Module parameters */
 114 module_param(debug, int, S_IRUGO | S_IWUSR);
 115 MODULE_PARM_DESC(debug, "Debug enabled or not");
 116
 117 /* All interrupt in transfers are collected in a ring buffer to
 118  * avoid racing conditions and get better performance of the driver.
 119  */
 120 static int ring_buffer_size = 128;
 121 module_param(ring_buffer_size, int, 0);
 122 MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size in reports");
 123
 124 /* The write_buffer can contain more than one interrupt out transfer.
 125  */
 126 static int write_buffer_size = 10;
 127 module_param(write_buffer_size, int, 0);
 128 MODULE_PARM_DESC(write_buffer_size, "Write buffer size in reports");
 129
 130 /* As of kernel version 2.6.4 ehci-hcd uses an
 131  * "only one interrupt transfer per frame" shortcut
 132  * to simplify the scheduling of periodic transfers.
 133  * This conflicts with our standard 1ms intervals for in and out URBs.
 134  * We use default intervals of 2ms for in and 2ms for out transfers,
 135  * which should be fast enough.
 136  * Increase the interval to allow more devices that do interrupt transfers,
 137  * or set to 1 to use the standard interval from the endpoint descriptors.
 138  */
 139 static int min_interrupt_in_interval = 2;
 140 module_param(min_interrupt_in_interval, int, 0);
 141 MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms");
 142
 143 static int min_interrupt_out_interval = 2;
 144 module_param(min_interrupt_out_interval, int, 0);
 145 MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms");
 146
 147 /* Structure to hold all of our device specific stuff */
 148 struct ld_usb {
 149         struct semaphore        sem;            /* locks this structure */
 150         struct usb_interface*   intf;           /* save off the usb interface pointer */
 151
 152         int                     open_count;     /* number of times this port has been opened */
 153
 154         char*                   ring_buffer;
 155         unsigned int            ring_head;
 156         unsigned int            ring_tail;
 157
 158         wait_queue_head_t       read_wait;
 159         wait_queue_head_t       write_wait;
 160
 161         char*                   interrupt_in_buffer;
 162         struct usb_endpoint_descriptor* interrupt_in_endpoint;
 163         struct urb*             interrupt_in_urb;
 164         int                     interrupt_in_interval;
 165         size_t                  interrupt_in_endpoint_size;
 166         int                     interrupt_in_running;
 167         int                     interrupt_in_done;
 168         int                     buffer_overflow;
 169         spinlock_t              rbsl;
 170
 171         char*                   interrupt_out_buffer;
 172         struct usb_endpoint_descriptor* interrupt_out_endpoint;
 173         struct urb*             interrupt_out_urb;
 174         int                     interrupt_out_interval;
 175         size_t                  interrupt_out_endpoint_size;
 176         int                     interrupt_out_busy;
 177 };
 178
 179 static struct usb_driver ld_usb_driver;
 180
 181 /**
 182  *      ld_usb_abort_transfers
 183  *      aborts transfers and frees associated data structures
 184  */
 185 static void ld_usb_abort_transfers(struct ld_usb *dev)
 186 {
 187         /* shutdown transfer */
 188         if (dev->interrupt_in_running) {
 189                 dev->interrupt_in_running = 0;
 190                 if (dev->intf)
 191                         usb_kill_urb(dev->interrupt_in_urb);
 192         }
 193         if (dev->interrupt_out_busy)
 194                 if (dev->intf)
 195                         usb_kill_urb(dev->interrupt_out_urb);
 196 }
 197
 198 /**
 199  *      ld_usb_delete
 200  */
 201 static void ld_usb_delete(struct ld_usb *dev)
 202 {
 203         ld_usb_abort_transfers(dev);
 204
 205         /* free data structures */
 206         usb_free_urb(dev->interrupt_in_urb);
 207         usb_free_urb(dev->interrupt_out_urb);
 208         kfree(dev->ring_buffer);
 209         kfree(dev->interrupt_in_buffer);
 210         kfree(dev->interrupt_out_buffer);
 211         kfree(dev);
 212 }
 213
 214 /**
 215  *      ld_usb_interrupt_in_callback
 216  */
 217 static void ld_usb_interrupt_in_callback(struct urb *urb)
 218 {
 219         struct ld_usb *dev = urb->context;
 220         size_t *actual_buffer;
 221         unsigned int next_ring_head;
 222         int status = urb->status;
 223         int retval;
 224
 225         if (status) {
 226                 if (status == -ENOENT ||
 227                     status == -ECONNRESET ||
 228                     status == -ESHUTDOWN) {
 229                         goto exit;
 230                 } else {
 231                         dbg_info(&dev->intf->dev, "%s: nonzero status received: %d\n",
 232                                  __FUNCTION__, status);
 233                         spin_lock(&dev->rbsl);
 234                         goto resubmit; /* maybe we can recover */
 235                 }
 236         }
 237
 238         spin_lock(&dev->rbsl);
 239         if (urb->actual_length > 0) {
 240                 next_ring_head = (dev->ring_head+1) % ring_buffer_size;
 241                 if (next_ring_head != dev->ring_tail) {
 242                         actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_head*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
 243                         /* actual_buffer gets urb->actual_length + interrupt_in_buffer */
 244                         *actual_buffer = urb->actual_length;
 245                         memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length);
 246                         dev->ring_head = next_ring_head;
 247                         dbg_info(&dev->intf->dev, "%s: received %d bytes\n",
 248                                  __FUNCTION__, urb->actual_length);
 249                 } else {
 250                         dev_warn(&dev->intf->dev,
 251                                  "Ring buffer overflow, %d bytes dropped\n",
 252                                  urb->actual_length);
 253                         dev->buffer_overflow = 1;
 254                 }
 255         }
 256
 257 resubmit:
 258         /* resubmit if we're still running */
 259         if (dev->interrupt_in_running && !dev->buffer_overflow && dev->intf) {
 260                 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC);
 261                 if (retval) {
 262                         dev_err(&dev->intf->dev,
 263                                 "usb_submit_urb failed (%d)\n", retval);
 264                         dev->buffer_overflow = 1;
 265                 }
 266         }
 267         spin_unlock(&dev->rbsl);
 268 exit:
 269         dev->interrupt_in_done = 1;
 270         wake_up_interruptible(&dev->read_wait);
 271 }
 272
 273 /**
 274  *      ld_usb_interrupt_out_callback
 275  */
 276 static void ld_usb_interrupt_out_callback(struct urb *urb)
 277 {
 278         struct ld_usb *dev = urb->context;
 279         int status = urb->status;
 280
 281         /* sync/async unlink faults aren't errors */
 282         if (status && !(status == -ENOENT ||
 283                         status == -ECONNRESET ||
 284                         status == -ESHUTDOWN))
 285                 dbg_info(&dev->intf->dev,
 286                          "%s - nonzero write interrupt status received: %d\n",
 287                          __FUNCTION__, status);
 288
 289         dev->interrupt_out_busy = 0;
 290         wake_up_interruptible(&dev->write_wait);
 291 }
 292
 293 /**
 294  *      ld_usb_open
 295  */
 296 static int ld_usb_open(struct inode *inode, struct file *file)
 297 {
 298         struct ld_usb *dev;
 299         int subminor;
 300         int retval;
 301         struct usb_interface *interface;
 302
 303         nonseekable_open(inode, file);
 304         subminor = iminor(inode);
 305
 306         interface = usb_find_interface(&ld_usb_driver, subminor);
 307
 308         if (!interface) {
 309                 err("%s - error, can't find device for minor %d\n",
 310                      __FUNCTION__, subminor);
 311                 return -ENODEV;
 312         }
 313
 314         dev = usb_get_intfdata(interface);
 315
 316         if (!dev)
 317                 return -ENODEV;
 318
 319         /* lock this device */
 320         if (down_interruptible(&dev->sem))
 321                 return -ERESTARTSYS;
 322
 323         /* allow opening only once */
 324         if (dev->open_count) {
 325                 retval = -EBUSY;
 326                 goto unlock_exit;
 327         }
 328         dev->open_count = 1;
 329
 330         /* initialize in direction */
 331         dev->ring_head = 0;
 332         dev->ring_tail = 0;
 333         dev->buffer_overflow = 0;
 334         usb_fill_int_urb(dev->interrupt_in_urb,
 335                          interface_to_usbdev(interface),
 336                          usb_rcvintpipe(interface_to_usbdev(interface),
 337                                         dev->interrupt_in_endpoint->bEndpointAddress),
 338                          dev->interrupt_in_buffer,
 339                          dev->interrupt_in_endpoint_size,
 340                          ld_usb_interrupt_in_callback,
 341                          dev,
 342                          dev->interrupt_in_interval);
 343
 344         dev->interrupt_in_running = 1;
 345         dev->interrupt_in_done = 0;
 346
 347         retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
 348         if (retval) {
 349                 dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval);
 350                 dev->interrupt_in_running = 0;
 351                 dev->open_count = 0;
 352                 goto unlock_exit;
 353         }
 354
 355         /* save device in the file's private structure */
 356         file->private_data = dev;
 357
 358 unlock_exit:
 359         up(&dev->sem);
 360
 361         return retval;
 362 }
 363
 364 /**
 365  *      ld_usb_release
 366  */
 367 static int ld_usb_release(struct inode *inode, struct file *file)
 368 {
 369         struct ld_usb *dev;
 370         int retval = 0;
 371
 372         dev = file->private_data;
 373
 374         if (dev == NULL) {
 375                 retval = -ENODEV;
 376                 goto exit;
 377         }
 378
 379         if (down_interruptible(&dev->sem)) {
 380                 retval = -ERESTARTSYS;
 381                 goto exit;
 382         }
 383
 384         if (dev->open_count != 1) {
 385                 retval = -ENODEV;
 386                 goto unlock_exit;
 387         }
 388         if (dev->intf == NULL) {
 389                 /* the device was unplugged before the file was released */
 390                 up(&dev->sem);
 391                 /* unlock here as ld_usb_delete frees dev */
 392                 ld_usb_delete(dev);
 393                 goto exit;
 394         }
 395
 396         /* wait until write transfer is finished */
 397         if (dev->interrupt_out_busy)
 398                 wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ);
 399         ld_usb_abort_transfers(dev);
 400         dev->open_count = 0;
 401
 402 unlock_exit:
 403         up(&dev->sem);
 404
 405 exit:
 406         return retval;
 407 }
 408
 409 /**
 410  *      ld_usb_poll
 411  */
 412 static unsigned int ld_usb_poll(struct file *file, poll_table *wait)
 413 {
 414         struct ld_usb *dev;
 415         unsigned int mask = 0;
 416
 417         dev = file->private_data;
 418
 419         poll_wait(file, &dev->read_wait, wait);
 420         poll_wait(file, &dev->write_wait, wait);
 421
 422         if (dev->ring_head != dev->ring_tail)
 423                 mask |= POLLIN | POLLRDNORM;
 424         if (!dev->interrupt_out_busy)
 425                 mask |= POLLOUT | POLLWRNORM;
 426
 427         return mask;
 428 }
 429
 430 /**
 431  *      ld_usb_read
 432  */
 433 static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count,
 434                            loff_t *ppos)
 435 {
 436         struct ld_usb *dev;
 437         size_t *actual_buffer;
 438         size_t bytes_to_read;
 439         int retval = 0;
 440         int rv;
 441
 442         dev = file->private_data;
 443
 444         /* verify that we actually have some data to read */
 445         if (count == 0)
 446                 goto exit;
 447
 448         /* lock this object */
 449         if (down_interruptible(&dev->sem)) {
 450                 retval = -ERESTARTSYS;
 451                 goto exit;
 452         }
 453
 454         /* verify that the device wasn't unplugged */
 455         if (dev->intf == NULL) {
 456                 retval = -ENODEV;
 457                 err("No device or device unplugged %d\n", retval);
 458                 goto unlock_exit;
 459         }
 460
 461         /* wait for data */
 462         spin_lock_irq(&dev->rbsl);
 463         if (dev->ring_head == dev->ring_tail) {
 464                 dev->interrupt_in_done = 0;
 465                 spin_unlock_irq(&dev->rbsl);
 466                 if (file->f_flags & O_NONBLOCK) {
 467                         retval = -EAGAIN;
 468                         goto unlock_exit;
 469                 }
 470                 retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done);
 471                 if (retval < 0)
 472                         goto unlock_exit;
 473         } else {
 474                 spin_unlock_irq(&dev->rbsl);
 475         }
 476
 477         /* actual_buffer contains actual_length + interrupt_in_buffer */
 478         actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_tail*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
 479         bytes_to_read = min(count, *actual_buffer);
 480         if (bytes_to_read < *actual_buffer)
 481                 dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n",
 482                          *actual_buffer-bytes_to_read);
 483
 484         /* copy one interrupt_in_buffer from ring_buffer into userspace */
 485         if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) {
 486                 retval = -EFAULT;
 487                 goto unlock_exit;
 488         }
 489         dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size;
 490
 491         retval = bytes_to_read;
 492
 493         spin_lock_irq(&dev->rbsl);
 494         if (dev->buffer_overflow) {
 495                 dev->buffer_overflow = 0;
 496                 spin_unlock_irq(&dev->rbsl);
 497                 rv = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
 498                 if (rv < 0)
 499                         dev->buffer_overflow = 1;
 500         } else {
 501                 spin_unlock_irq(&dev->rbsl);
 502         }
 503
 504 unlock_exit:
 505         /* unlock the device */
 506         up(&dev->sem);
 507
 508 exit:
 509         return retval;
 510 }
 511
 512 /**
 513  *      ld_usb_write
 514  */
 515 static ssize_t ld_usb_write(struct file *file, const char __user *buffer,
 516                             size_t count, loff_t *ppos)
 517 {
 518         struct ld_usb *dev;
 519         size_t bytes_to_write;
 520         int retval = 0;
 521
 522         dev = file->private_data;
 523
 524         /* verify that we actually have some data to write */
 525         if (count == 0)
 526                 goto exit;
 527
 528         /* lock this object */
 529         if (down_interruptible(&dev->sem)) {
 530                 retval = -ERESTARTSYS;
 531                 goto exit;
 532         }
 533
 534         /* verify that the device wasn't unplugged */
 535         if (dev->intf == NULL) {
 536                 retval = -ENODEV;
 537                 err("No device or device unplugged %d\n", retval);
 538                 goto unlock_exit;
 539         }
 540
 541         /* wait until previous transfer is finished */
 542         if (dev->interrupt_out_busy) {
 543                 if (file->f_flags & O_NONBLOCK) {
 544                         retval = -EAGAIN;
 545                         goto unlock_exit;
 546                 }
 547                 retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy);
 548                 if (retval < 0) {
 549                         goto unlock_exit;
 550                 }
 551         }
 552
 553         /* write the data into interrupt_out_buffer from userspace */
 554         bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size);
 555         if (bytes_to_write < count)
 556                 dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n",count-bytes_to_write);
 557         dbg_info(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n", __FUNCTION__, count, bytes_to_write);
 558
 559         if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) {
 560                 retval = -EFAULT;
 561                 goto unlock_exit;
 562         }
 563
 564         if (dev->interrupt_out_endpoint == NULL) {
 565                 /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */
 566                 retval = usb_control_msg(interface_to_usbdev(dev->intf),
 567                                          usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0),
 568                                          9,
 569                                          USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
 570                                          1 << 8, 0,
 571                                          dev->interrupt_out_buffer,
 572                                          bytes_to_write,
 573                                          USB_CTRL_SET_TIMEOUT * HZ);
 574                 if (retval < 0)
 575                         err("Couldn't submit HID_REQ_SET_REPORT %d\n", retval);
 576                 goto unlock_exit;
 577         }
 578
 579         /* send off the urb */
 580         usb_fill_int_urb(dev->interrupt_out_urb,
 581                          interface_to_usbdev(dev->intf),
 582                          usb_sndintpipe(interface_to_usbdev(dev->intf),
 583                                         dev->interrupt_out_endpoint->bEndpointAddress),
 584                          dev->interrupt_out_buffer,
 585                          bytes_to_write,
 586                          ld_usb_interrupt_out_callback,
 587                          dev,
 588                          dev->interrupt_out_interval);
 589
 590         dev->interrupt_out_busy = 1;
 591         wmb();
 592
 593         retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL);
 594         if (retval) {
 595                 dev->interrupt_out_busy = 0;
 596                 err("Couldn't submit interrupt_out_urb %d\n", retval);
 597                 goto unlock_exit;
 598         }
 599         retval = bytes_to_write;
 600
 601 unlock_exit:
 602         /* unlock the device */
 603         up(&dev->sem);
 604
 605 exit:
 606         return retval;
 607 }
 608
 609 /* file operations needed when we register this driver */
 610 static const struct file_operations ld_usb_fops = {
 611         .owner =        THIS_MODULE,
 612         .read  =        ld_usb_read,
 613         .write =        ld_usb_write,
 614         .open =         ld_usb_open,
 615         .release =      ld_usb_release,
 616         .poll =         ld_usb_poll,
 617 };
 618
 619 /*
 620  * usb class driver info in order to get a minor number from the usb core,
 621  * and to have the device registered with the driver core
 622  */
 623 static struct usb_class_driver ld_usb_class = {
 624         .name =         "ldusb%d",
 625         .fops =         &ld_usb_fops,
 626         .minor_base =   USB_LD_MINOR_BASE,
 627 };
 628
 629 /**
 630  *      ld_usb_probe
 631  *
 632  *      Called by the usb core when a new device is connected that it thinks
 633  *      this driver might be interested in.
 634  */
 635 static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
 636 {
 637         struct usb_device *udev = interface_to_usbdev(intf);
 638         struct ld_usb *dev = NULL;
 639         struct usb_host_interface *iface_desc;
 640         struct usb_endpoint_descriptor *endpoint;
 641         char *buffer;
 642         int i;
 643         int retval = -ENOMEM;
 644
 645         /* allocate memory for our device state and intialize it */
 646
 647         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 648         if (dev == NULL) {
 649                 dev_err(&intf->dev, "Out of memory\n");
 650                 goto exit;
 651         }
 652         init_MUTEX(&dev->sem);
 653         spin_lock_init(&dev->rbsl);
 654         dev->intf = intf;
 655         init_waitqueue_head(&dev->read_wait);
 656         init_waitqueue_head(&dev->write_wait);
 657
 658         /* workaround for early firmware versions on fast computers */
 659         if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) &&
 660             ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) ||
 661              (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) &&
 662             (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) {
 663                 buffer = kmalloc(256, GFP_KERNEL);
 664                 if (buffer == NULL) {
 665                         dev_err(&intf->dev, "Couldn't allocate string buffer\n");
 666                         goto error;
 667                 }
 668                 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */
 669                 usb_string(udev, 255, buffer, 256);
 670                 kfree(buffer);
 671         }
 672
 673         iface_desc = intf->cur_altsetting;
 674
 675         /* set up the endpoint information */
 676         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 677                 endpoint = &iface_desc->endpoint[i].desc;
 678
 679                 if (usb_endpoint_is_int_in(endpoint))
 680                         dev->interrupt_in_endpoint = endpoint;
 681
 682                 if (usb_endpoint_is_int_out(endpoint))
 683                         dev->interrupt_out_endpoint = endpoint;
 684         }
 685         if (dev->interrupt_in_endpoint == NULL) {
 686                 dev_err(&intf->dev, "Interrupt in endpoint not found\n");
 687                 goto error;
 688         }
 689         if (dev->interrupt_out_endpoint == NULL)
 690                 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n");
 691
 692         dev->interrupt_in_endpoint_size = le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize);
 693         dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL);
 694         if (!dev->ring_buffer) {
 695                 dev_err(&intf->dev, "Couldn't allocate ring_buffer\n");
 696                 goto error;
 697         }
 698         dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL);
 699         if (!dev->interrupt_in_buffer) {
 700                 dev_err(&intf->dev, "Couldn't allocate interrupt_in_buffer\n");
 701                 goto error;
 702         }
 703         dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
 704         if (!dev->interrupt_in_urb) {
 705                 dev_err(&intf->dev, "Couldn't allocate interrupt_in_urb\n");
 706                 goto error;
 707         }
 708         dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? le16_to_cpu(dev->interrupt_out_endpoint->wMaxPacketSize) :
 709                                                                          udev->descriptor.bMaxPacketSize0;
 710         dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL);
 711         if (!dev->interrupt_out_buffer) {
 712                 dev_err(&intf->dev, "Couldn't allocate interrupt_out_buffer\n");
 713                 goto error;
 714         }
 715         dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
 716         if (!dev->interrupt_out_urb) {
 717                 dev_err(&intf->dev, "Couldn't allocate interrupt_out_urb\n");
 718                 goto error;
 719         }
 720         dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval;
 721         if (dev->interrupt_out_endpoint)
 722                 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval;
 723
 724         /* we can register the device now, as it is ready */
 725         usb_set_intfdata(intf, dev);
 726
 727         retval = usb_register_dev(intf, &ld_usb_class);
 728         if (retval) {
 729                 /* something prevented us from registering this driver */
 730                 dev_err(&intf->dev, "Not able to get a minor for this device.\n");
 731                 usb_set_intfdata(intf, NULL);
 732                 goto error;
 733         }
 734
 735         /* let the user know what node this device is now attached to */
 736         dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n",
 737                 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor);
 738
 739 exit:
 740         return retval;
 741
 742 error:
 743         ld_usb_delete(dev);
 744
 745         return retval;
 746 }
 747
 748 /**
 749  *      ld_usb_disconnect
 750  *
 751  *      Called by the usb core when the device is removed from the system.
 752  */
 753 static void ld_usb_disconnect(struct usb_interface *intf)
 754 {
 755         struct ld_usb *dev;
 756         int minor;
 757
 758         dev = usb_get_intfdata(intf);
 759         usb_set_intfdata(intf, NULL);
 760
 761         minor = intf->minor;
 762
 763         /* give back our minor */
 764         usb_deregister_dev(intf, &ld_usb_class);
 765
 766         down(&dev->sem);
 767
 768         /* if the device is not opened, then we clean up right now */
 769         if (!dev->open_count) {
 770                 up(&dev->sem);
 771                 ld_usb_delete(dev);
 772         } else {
 773                 dev->intf = NULL;
 774                 up(&dev->sem);
 775         }
 776
 777         dev_info(&intf->dev, "LD USB Device #%d now disconnected\n",
 778                  (minor - USB_LD_MINOR_BASE));
 779 }
 780
 781 /* usb specific object needed to register this driver with the usb subsystem */
 782 static struct usb_driver ld_usb_driver = {
 783         .name =         "ldusb",
 784         .probe =        ld_usb_probe,
 785         .disconnect =   ld_usb_disconnect,
 786         .id_table =     ld_usb_table,
 787 };
 788
 789 /**
 790  *      ld_usb_init
 791  */
 792 static int __init ld_usb_init(void)
 793 {
 794         int retval;
 795
 796         /* register this driver with the USB subsystem */
 797         retval = usb_register(&ld_usb_driver);
 798         if (retval)
 799                 err("usb_register failed for the "__FILE__" driver. Error number %d\n", retval);
 800
 801         return retval;
 802 }
 803
 804 /**
 805  *      ld_usb_exit
 806  */
 807 static void __exit ld_usb_exit(void)
 808 {
 809         /* deregister this driver with the USB subsystem */
 810         usb_deregister(&ld_usb_driver);
 811 }
 812
 813 module_init(ld_usb_init);
 814 module_exit(ld_usb_exit);
 815