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 /* prevent races between open() and disconnect() */
 180 static DEFINE_MUTEX(disconnect_mutex);
 181
 182 static struct usb_driver ld_usb_driver;
 183
 184 /**
 185  *      ld_usb_abort_transfers
 186  *      aborts transfers and frees associated data structures
 187  */
 188 static void ld_usb_abort_transfers(struct ld_usb *dev)
 189 {
 190         /* shutdown transfer */
 191         if (dev->interrupt_in_running) {
 192                 dev->interrupt_in_running = 0;
 193                 if (dev->intf)
 194                         usb_kill_urb(dev->interrupt_in_urb);
 195         }
 196         if (dev->interrupt_out_busy)
 197                 if (dev->intf)
 198                         usb_kill_urb(dev->interrupt_out_urb);
 199 }
 200
 201 /**
 202  *      ld_usb_delete
 203  */
 204 static void ld_usb_delete(struct ld_usb *dev)
 205 {
 206         ld_usb_abort_transfers(dev);
 207
 208         /* free data structures */
 209         usb_free_urb(dev->interrupt_in_urb);
 210         usb_free_urb(dev->interrupt_out_urb);
 211         kfree(dev->ring_buffer);
 212         kfree(dev->interrupt_in_buffer);
 213         kfree(dev->interrupt_out_buffer);
 214         kfree(dev);
 215 }
 216
 217 /**
 218  *      ld_usb_interrupt_in_callback
 219  */
 220 static void ld_usb_interrupt_in_callback(struct urb *urb)
 221 {
 222         struct ld_usb *dev = urb->context;
 223         size_t *actual_buffer;
 224         unsigned int next_ring_head;
 225         int retval;
 226
 227         if (urb->status) {
 228                 if (urb->status == -ENOENT ||
 229                     urb->status == -ECONNRESET ||
 230                     urb->status == -ESHUTDOWN) {
 231                         goto exit;
 232                 } else {
 233                         dbg_info(&dev->intf->dev, "%s: nonzero status received: %d\n",
 234                                  __FUNCTION__, urb->status);
 235                         spin_lock(&dev->rbsl);
 236                         goto resubmit; /* maybe we can recover */
 237                 }
 238         }
 239
 240         spin_lock(&dev->rbsl);
 241         if (urb->actual_length > 0) {
 242                 next_ring_head = (dev->ring_head+1) % ring_buffer_size;
 243                 if (next_ring_head != dev->ring_tail) {
 244                         actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_head*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
 245                         /* actual_buffer gets urb->actual_length + interrupt_in_buffer */
 246                         *actual_buffer = urb->actual_length;
 247                         memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length);
 248                         dev->ring_head = next_ring_head;
 249                         dbg_info(&dev->intf->dev, "%s: received %d bytes\n",
 250                                  __FUNCTION__, urb->actual_length);
 251                 } else {
 252                         dev_warn(&dev->intf->dev,
 253                                  "Ring buffer overflow, %d bytes dropped\n",
 254                                  urb->actual_length);
 255                         dev->buffer_overflow = 1;
 256                 }
 257         }
 258
 259 resubmit:
 260         /* resubmit if we're still running */
 261         if (dev->interrupt_in_running && !dev->buffer_overflow && dev->intf) {
 262                 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC);
 263                 if (retval) {
 264                         dev_err(&dev->intf->dev,
 265                                 "usb_submit_urb failed (%d)\n", retval);
 266                         dev->buffer_overflow = 1;
 267                 }
 268         }
 269         spin_unlock(&dev->rbsl);
 270 exit:
 271         dev->interrupt_in_done = 1;
 272         wake_up_interruptible(&dev->read_wait);
 273 }
 274
 275 /**
 276  *      ld_usb_interrupt_out_callback
 277  */
 278 static void ld_usb_interrupt_out_callback(struct urb *urb)
 279 {
 280         struct ld_usb *dev = urb->context;
 281
 282         /* sync/async unlink faults aren't errors */
 283         if (urb->status && !(urb->status == -ENOENT ||
 284                              urb->status == -ECONNRESET ||
 285                              urb->status == -ESHUTDOWN))
 286                 dbg_info(&dev->intf->dev,
 287                          "%s - nonzero write interrupt status received: %d\n",
 288                          __FUNCTION__, urb->status);
 289
 290         dev->interrupt_out_busy = 0;
 291         wake_up_interruptible(&dev->write_wait);
 292 }
 293
 294 /**
 295  *      ld_usb_open
 296  */
 297 static int ld_usb_open(struct inode *inode, struct file *file)
 298 {
 299         struct ld_usb *dev;
 300         int subminor;
 301         int retval = 0;
 302         struct usb_interface *interface;
 303
 304         nonseekable_open(inode, file);
 305         subminor = iminor(inode);
 306
 307         mutex_lock(&disconnect_mutex);
 308
 309         interface = usb_find_interface(&ld_usb_driver, subminor);
 310
 311         if (!interface) {
 312                 err("%s - error, can't find device for minor %d\n",
 313                      __FUNCTION__, subminor);
 314                 retval = -ENODEV;
 315                 goto unlock_disconnect_exit;
 316         }
 317
 318         dev = usb_get_intfdata(interface);
 319
 320         if (!dev) {
 321                 retval = -ENODEV;
 322                 goto unlock_disconnect_exit;
 323         }
 324
 325         /* lock this device */
 326         if (down_interruptible(&dev->sem)) {
 327                 retval = -ERESTARTSYS;
 328                 goto unlock_disconnect_exit;
 329         }
 330
 331         /* allow opening only once */
 332         if (dev->open_count) {
 333                 retval = -EBUSY;
 334                 goto unlock_exit;
 335         }
 336         dev->open_count = 1;
 337
 338         /* initialize in direction */
 339         dev->ring_head = 0;
 340         dev->ring_tail = 0;
 341         dev->buffer_overflow = 0;
 342         usb_fill_int_urb(dev->interrupt_in_urb,
 343                          interface_to_usbdev(interface),
 344                          usb_rcvintpipe(interface_to_usbdev(interface),
 345                                         dev->interrupt_in_endpoint->bEndpointAddress),
 346                          dev->interrupt_in_buffer,
 347                          dev->interrupt_in_endpoint_size,
 348                          ld_usb_interrupt_in_callback,
 349                          dev,
 350                          dev->interrupt_in_interval);
 351
 352         dev->interrupt_in_running = 1;
 353         dev->interrupt_in_done = 0;
 354
 355         retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
 356         if (retval) {
 357                 dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval);
 358                 dev->interrupt_in_running = 0;
 359                 dev->open_count = 0;
 360                 goto unlock_exit;
 361         }
 362
 363         /* save device in the file's private structure */
 364         file->private_data = dev;
 365
 366 unlock_exit:
 367         up(&dev->sem);
 368
 369 unlock_disconnect_exit:
 370         mutex_unlock(&disconnect_mutex);
 371
 372         return retval;
 373 }
 374
 375 /**
 376  *      ld_usb_release
 377  */
 378 static int ld_usb_release(struct inode *inode, struct file *file)
 379 {
 380         struct ld_usb *dev;
 381         int retval = 0;
 382
 383         dev = file->private_data;
 384
 385         if (dev == NULL) {
 386                 retval = -ENODEV;
 387                 goto exit;
 388         }
 389
 390         if (down_interruptible(&dev->sem)) {
 391                 retval = -ERESTARTSYS;
 392                 goto exit;
 393         }
 394
 395         if (dev->open_count != 1) {
 396                 retval = -ENODEV;
 397                 goto unlock_exit;
 398         }
 399         if (dev->intf == NULL) {
 400                 /* the device was unplugged before the file was released */
 401                 up(&dev->sem);
 402                 /* unlock here as ld_usb_delete frees dev */
 403                 ld_usb_delete(dev);
 404                 goto exit;
 405         }
 406
 407         /* wait until write transfer is finished */
 408         if (dev->interrupt_out_busy)
 409                 wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ);
 410         ld_usb_abort_transfers(dev);
 411         dev->open_count = 0;
 412
 413 unlock_exit:
 414         up(&dev->sem);
 415
 416 exit:
 417         return retval;
 418 }
 419
 420 /**
 421  *      ld_usb_poll
 422  */
 423 static unsigned int ld_usb_poll(struct file *file, poll_table *wait)
 424 {
 425         struct ld_usb *dev;
 426         unsigned int mask = 0;
 427
 428         dev = file->private_data;
 429
 430         poll_wait(file, &dev->read_wait, wait);
 431         poll_wait(file, &dev->write_wait, wait);
 432
 433         if (dev->ring_head != dev->ring_tail)
 434                 mask |= POLLIN | POLLRDNORM;
 435         if (!dev->interrupt_out_busy)
 436                 mask |= POLLOUT | POLLWRNORM;
 437
 438         return mask;
 439 }
 440
 441 /**
 442  *      ld_usb_read
 443  */
 444 static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count,
 445                            loff_t *ppos)
 446 {
 447         struct ld_usb *dev;
 448         size_t *actual_buffer;
 449         size_t bytes_to_read;
 450         int retval = 0;
 451         int rv;
 452
 453         dev = file->private_data;
 454
 455         /* verify that we actually have some data to read */
 456         if (count == 0)
 457                 goto exit;
 458
 459         /* lock this object */
 460         if (down_interruptible(&dev->sem)) {
 461                 retval = -ERESTARTSYS;
 462                 goto exit;
 463         }
 464
 465         /* verify that the device wasn't unplugged */
 466         if (dev->intf == NULL) {
 467                 retval = -ENODEV;
 468                 err("No device or device unplugged %d\n", retval);
 469                 goto unlock_exit;
 470         }
 471
 472         /* wait for data */
 473         spin_lock_irq(&dev->rbsl);
 474         if (dev->ring_head == dev->ring_tail) {
 475                 dev->interrupt_in_done = 0;
 476                 spin_unlock_irq(&dev->rbsl);
 477                 if (file->f_flags & O_NONBLOCK) {
 478                         retval = -EAGAIN;
 479                         goto unlock_exit;
 480                 }
 481                 retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done);
 482                 if (retval < 0)
 483                         goto unlock_exit;
 484         } else {
 485                 spin_unlock_irq(&dev->rbsl);
 486         }
 487
 488         /* actual_buffer contains actual_length + interrupt_in_buffer */
 489         actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_tail*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
 490         bytes_to_read = min(count, *actual_buffer);
 491         if (bytes_to_read < *actual_buffer)
 492                 dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n",
 493                          *actual_buffer-bytes_to_read);
 494
 495         /* copy one interrupt_in_buffer from ring_buffer into userspace */
 496         if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) {
 497                 retval = -EFAULT;
 498                 goto unlock_exit;
 499         }
 500         dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size;
 501
 502         retval = bytes_to_read;
 503
 504         spin_lock_irq(&dev->rbsl);
 505         if (dev->buffer_overflow) {
 506                 dev->buffer_overflow = 0;
 507                 spin_unlock_irq(&dev->rbsl);
 508                 rv = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
 509                 if (rv < 0)
 510                         dev->buffer_overflow = 1;
 511         } else {
 512                 spin_unlock_irq(&dev->rbsl);
 513         }
 514
 515 unlock_exit:
 516         /* unlock the device */
 517         up(&dev->sem);
 518
 519 exit:
 520         return retval;
 521 }
 522
 523 /**
 524  *      ld_usb_write
 525  */
 526 static ssize_t ld_usb_write(struct file *file, const char __user *buffer,
 527                             size_t count, loff_t *ppos)
 528 {
 529         struct ld_usb *dev;
 530         size_t bytes_to_write;
 531         int retval = 0;
 532
 533         dev = file->private_data;
 534
 535         /* verify that we actually have some data to write */
 536         if (count == 0)
 537                 goto exit;
 538
 539         /* lock this object */
 540         if (down_interruptible(&dev->sem)) {
 541                 retval = -ERESTARTSYS;
 542                 goto exit;
 543         }
 544
 545         /* verify that the device wasn't unplugged */
 546         if (dev->intf == NULL) {
 547                 retval = -ENODEV;
 548                 err("No device or device unplugged %d\n", retval);
 549                 goto unlock_exit;
 550         }
 551
 552         /* wait until previous transfer is finished */
 553         if (dev->interrupt_out_busy) {
 554                 if (file->f_flags & O_NONBLOCK) {
 555                         retval = -EAGAIN;
 556                         goto unlock_exit;
 557                 }
 558                 retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy);
 559                 if (retval < 0) {
 560                         goto unlock_exit;
 561                 }
 562         }
 563
 564         /* write the data into interrupt_out_buffer from userspace */
 565         bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size);
 566         if (bytes_to_write < count)
 567                 dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n",count-bytes_to_write);
 568         dbg_info(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n", __FUNCTION__, count, bytes_to_write);
 569
 570         if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) {
 571                 retval = -EFAULT;
 572                 goto unlock_exit;
 573         }
 574
 575         if (dev->interrupt_out_endpoint == NULL) {
 576                 /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */
 577                 retval = usb_control_msg(interface_to_usbdev(dev->intf),
 578                                          usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0),
 579                                          9,
 580                                          USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
 581                                          1 << 8, 0,
 582                                          dev->interrupt_out_buffer,
 583                                          bytes_to_write,
 584                                          USB_CTRL_SET_TIMEOUT * HZ);
 585                 if (retval < 0)
 586                         err("Couldn't submit HID_REQ_SET_REPORT %d\n", retval);
 587                 goto unlock_exit;
 588         }
 589
 590         /* send off the urb */
 591         usb_fill_int_urb(dev->interrupt_out_urb,
 592                          interface_to_usbdev(dev->intf),
 593                          usb_sndintpipe(interface_to_usbdev(dev->intf),
 594                                         dev->interrupt_out_endpoint->bEndpointAddress),
 595                          dev->interrupt_out_buffer,
 596                          bytes_to_write,
 597                          ld_usb_interrupt_out_callback,
 598                          dev,
 599                          dev->interrupt_out_interval);
 600
 601         dev->interrupt_out_busy = 1;
 602         wmb();
 603
 604         retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL);
 605         if (retval) {
 606                 dev->interrupt_out_busy = 0;
 607                 err("Couldn't submit interrupt_out_urb %d\n", retval);
 608                 goto unlock_exit;
 609         }
 610         retval = bytes_to_write;
 611
 612 unlock_exit:
 613         /* unlock the device */
 614         up(&dev->sem);
 615
 616 exit:
 617         return retval;
 618 }
 619
 620 /* file operations needed when we register this driver */
 621 static const struct file_operations ld_usb_fops = {
 622         .owner =        THIS_MODULE,
 623         .read  =        ld_usb_read,
 624         .write =        ld_usb_write,
 625         .open =         ld_usb_open,
 626         .release =      ld_usb_release,
 627         .poll =         ld_usb_poll,
 628 };
 629
 630 /*
 631  * usb class driver info in order to get a minor number from the usb core,
 632  * and to have the device registered with the driver core
 633  */
 634 static struct usb_class_driver ld_usb_class = {
 635         .name =         "ldusb%d",
 636         .fops =         &ld_usb_fops,
 637         .minor_base =   USB_LD_MINOR_BASE,
 638 };
 639
 640 /**
 641  *      ld_usb_probe
 642  *
 643  *      Called by the usb core when a new device is connected that it thinks
 644  *      this driver might be interested in.
 645  */
 646 static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
 647 {
 648         struct usb_device *udev = interface_to_usbdev(intf);
 649         struct ld_usb *dev = NULL;
 650         struct usb_host_interface *iface_desc;
 651         struct usb_endpoint_descriptor *endpoint;
 652         char *buffer;
 653         int i;
 654         int retval = -ENOMEM;
 655
 656         /* allocate memory for our device state and intialize it */
 657
 658         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 659         if (dev == NULL) {
 660                 dev_err(&intf->dev, "Out of memory\n");
 661                 goto exit;
 662         }
 663         init_MUTEX(&dev->sem);
 664         spin_lock_init(&dev->rbsl);
 665         dev->intf = intf;
 666         init_waitqueue_head(&dev->read_wait);
 667         init_waitqueue_head(&dev->write_wait);
 668
 669         /* workaround for early firmware versions on fast computers */
 670         if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) &&
 671             ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) ||
 672              (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) &&
 673             (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) {
 674                 buffer = kmalloc(256, GFP_KERNEL);
 675                 if (buffer == NULL) {
 676                         dev_err(&intf->dev, "Couldn't allocate string buffer\n");
 677                         goto error;
 678                 }
 679                 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */
 680                 usb_string(udev, 255, buffer, 256);
 681                 kfree(buffer);
 682         }
 683
 684         iface_desc = intf->cur_altsetting;
 685
 686         /* set up the endpoint information */
 687         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 688                 endpoint = &iface_desc->endpoint[i].desc;
 689
 690                 if (usb_endpoint_is_int_in(endpoint))
 691                         dev->interrupt_in_endpoint = endpoint;
 692
 693                 if (usb_endpoint_is_int_out(endpoint))
 694                         dev->interrupt_out_endpoint = endpoint;
 695         }
 696         if (dev->interrupt_in_endpoint == NULL) {
 697                 dev_err(&intf->dev, "Interrupt in endpoint not found\n");
 698                 goto error;
 699         }
 700         if (dev->interrupt_out_endpoint == NULL)
 701                 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n");
 702
 703         dev->interrupt_in_endpoint_size = le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize);
 704         dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL);
 705         if (!dev->ring_buffer) {
 706                 dev_err(&intf->dev, "Couldn't allocate ring_buffer\n");
 707                 goto error;
 708         }
 709         dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL);
 710         if (!dev->interrupt_in_buffer) {
 711                 dev_err(&intf->dev, "Couldn't allocate interrupt_in_buffer\n");
 712                 goto error;
 713         }
 714         dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
 715         if (!dev->interrupt_in_urb) {
 716                 dev_err(&intf->dev, "Couldn't allocate interrupt_in_urb\n");
 717                 goto error;
 718         }
 719         dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? le16_to_cpu(dev->interrupt_out_endpoint->wMaxPacketSize) :
 720                                                                          udev->descriptor.bMaxPacketSize0;
 721         dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL);
 722         if (!dev->interrupt_out_buffer) {
 723                 dev_err(&intf->dev, "Couldn't allocate interrupt_out_buffer\n");
 724                 goto error;
 725         }
 726         dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
 727         if (!dev->interrupt_out_urb) {
 728                 dev_err(&intf->dev, "Couldn't allocate interrupt_out_urb\n");
 729                 goto error;
 730         }
 731         dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval;
 732         if (dev->interrupt_out_endpoint)
 733                 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval;
 734
 735         /* we can register the device now, as it is ready */
 736         usb_set_intfdata(intf, dev);
 737
 738         retval = usb_register_dev(intf, &ld_usb_class);
 739         if (retval) {
 740                 /* something prevented us from registering this driver */
 741                 dev_err(&intf->dev, "Not able to get a minor for this device.\n");
 742                 usb_set_intfdata(intf, NULL);
 743                 goto error;
 744         }
 745
 746         /* let the user know what node this device is now attached to */
 747         dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n",
 748                 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor);
 749
 750 exit:
 751         return retval;
 752
 753 error:
 754         ld_usb_delete(dev);
 755
 756         return retval;
 757 }
 758
 759 /**
 760  *      ld_usb_disconnect
 761  *
 762  *      Called by the usb core when the device is removed from the system.
 763  */
 764 static void ld_usb_disconnect(struct usb_interface *intf)
 765 {
 766         struct ld_usb *dev;
 767         int minor;
 768
 769         mutex_lock(&disconnect_mutex);
 770
 771         dev = usb_get_intfdata(intf);
 772         usb_set_intfdata(intf, NULL);
 773
 774         down(&dev->sem);
 775
 776         minor = intf->minor;
 777
 778         /* give back our minor */
 779         usb_deregister_dev(intf, &ld_usb_class);
 780
 781         /* if the device is not opened, then we clean up right now */
 782         if (!dev->open_count) {
 783                 up(&dev->sem);
 784                 ld_usb_delete(dev);
 785         } else {
 786                 dev->intf = NULL;
 787                 up(&dev->sem);
 788         }
 789
 790         mutex_unlock(&disconnect_mutex);
 791
 792         dev_info(&intf->dev, "LD USB Device #%d now disconnected\n",
 793                  (minor - USB_LD_MINOR_BASE));
 794 }
 795
 796 /* usb specific object needed to register this driver with the usb subsystem */
 797 static struct usb_driver ld_usb_driver = {
 798         .name =         "ldusb",
 799         .probe =        ld_usb_probe,
 800         .disconnect =   ld_usb_disconnect,
 801         .id_table =     ld_usb_table,
 802 };
 803
 804 /**
 805  *      ld_usb_init
 806  */
 807 static int __init ld_usb_init(void)
 808 {
 809         int retval;
 810
 811         /* register this driver with the USB subsystem */
 812         retval = usb_register(&ld_usb_driver);
 813         if (retval)
 814                 err("usb_register failed for the "__FILE__" driver. Error number %d\n", retval);
 815
 816         return retval;
 817 }
 818
 819 /**
 820  *      ld_usb_exit
 821  */
 822 static void __exit ld_usb_exit(void)
 823 {
 824         /* deregister this driver with the USB subsystem */
 825         usb_deregister(&ld_usb_driver);
 826 }
 827
 828 module_init(ld_usb_init);
 829 module_exit(ld_usb_exit);
 830