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 #define USB_DEVICE_ID_VERNIER_LCSPEC    0x0006
  65
  66 #ifdef CONFIG_USB_DYNAMIC_MINORS
  67 #define USB_LD_MINOR_BASE       0
  68 #else
  69 #define USB_LD_MINOR_BASE       176
  70 #endif
  71
  72 /* table of devices that work with this driver */
  73 static struct usb_device_id ld_usb_table [] = {
  74         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY) },
  75         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY) },
  76         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY) },
  77         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_JWM) },
  78         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_DMMP) },
  79         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIP) },
  80         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY1) },
  81         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY2) },
  82         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_VIDEOCOM) },
  83         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_COM3LAB) },
  84         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_TELEPORT) },
  85         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_NETWORKANALYSER) },
  86         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POWERCONTROL) },
  87         { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MACHINETEST) },
  88         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_LABPRO) },
  89         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_GOTEMP) },
  90         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_SKIP) },
  91         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_CYCLOPS) },
  92         { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_LCSPEC) },
  93         { }                                     /* Terminating entry */
  94 };
  95 MODULE_DEVICE_TABLE(usb, ld_usb_table);
  96 MODULE_VERSION("V0.13");
  97 MODULE_AUTHOR("Michael Hund <mhund@ld-didactic.de>");
  98 MODULE_DESCRIPTION("LD USB Driver");
  99 MODULE_LICENSE("GPL");
 100 MODULE_SUPPORTED_DEVICE("LD USB Devices");
 101
 102 #ifdef CONFIG_USB_DEBUG
 103         static int debug = 1;
 104 #else
 105         static int debug = 0;
 106 #endif
 107
 108 /* Use our own dbg macro */
 109 #define dbg_info(dev, format, arg...) do { if (debug) dev_info(dev , format , ## arg); } while (0)
 110
 111 /* Module parameters */
 112 module_param(debug, int, S_IRUGO | S_IWUSR);
 113 MODULE_PARM_DESC(debug, "Debug enabled or not");
 114
 115 /* All interrupt in transfers are collected in a ring buffer to
 116  * avoid racing conditions and get better performance of the driver.
 117  */
 118 static int ring_buffer_size = 128;
 119 module_param(ring_buffer_size, int, 0);
 120 MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size in reports");
 121
 122 /* The write_buffer can contain more than one interrupt out transfer.
 123  */
 124 static int write_buffer_size = 10;
 125 module_param(write_buffer_size, int, 0);
 126 MODULE_PARM_DESC(write_buffer_size, "Write buffer size in reports");
 127
 128 /* As of kernel version 2.6.4 ehci-hcd uses an
 129  * "only one interrupt transfer per frame" shortcut
 130  * to simplify the scheduling of periodic transfers.
 131  * This conflicts with our standard 1ms intervals for in and out URBs.
 132  * We use default intervals of 2ms for in and 2ms for out transfers,
 133  * which should be fast enough.
 134  * Increase the interval to allow more devices that do interrupt transfers,
 135  * or set to 1 to use the standard interval from the endpoint descriptors.
 136  */
 137 static int min_interrupt_in_interval = 2;
 138 module_param(min_interrupt_in_interval, int, 0);
 139 MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms");
 140
 141 static int min_interrupt_out_interval = 2;
 142 module_param(min_interrupt_out_interval, int, 0);
 143 MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms");
 144
 145 /* Structure to hold all of our device specific stuff */
 146 struct ld_usb {
 147         struct mutex            mutex;          /* locks this structure */
 148         struct usb_interface*   intf;           /* save off the usb interface pointer */
 149
 150         int                     open_count;     /* number of times this port has been opened */
 151
 152         char*                   ring_buffer;
 153         unsigned int            ring_head;
 154         unsigned int            ring_tail;
 155
 156         wait_queue_head_t       read_wait;
 157         wait_queue_head_t       write_wait;
 158
 159         char*                   interrupt_in_buffer;
 160         struct usb_endpoint_descriptor* interrupt_in_endpoint;
 161         struct urb*             interrupt_in_urb;
 162         int                     interrupt_in_interval;
 163         size_t                  interrupt_in_endpoint_size;
 164         int                     interrupt_in_running;
 165         int                     interrupt_in_done;
 166         int                     buffer_overflow;
 167         spinlock_t              rbsl;
 168
 169         char*                   interrupt_out_buffer;
 170         struct usb_endpoint_descriptor* interrupt_out_endpoint;
 171         struct urb*             interrupt_out_urb;
 172         int                     interrupt_out_interval;
 173         size_t                  interrupt_out_endpoint_size;
 174         int                     interrupt_out_busy;
 175 };
 176
 177 static struct usb_driver ld_usb_driver;
 178
 179 /**
 180  *      ld_usb_abort_transfers
 181  *      aborts transfers and frees associated data structures
 182  */
 183 static void ld_usb_abort_transfers(struct ld_usb *dev)
 184 {
 185         /* shutdown transfer */
 186         if (dev->interrupt_in_running) {
 187                 dev->interrupt_in_running = 0;
 188                 if (dev->intf)
 189                         usb_kill_urb(dev->interrupt_in_urb);
 190         }
 191         if (dev->interrupt_out_busy)
 192                 if (dev->intf)
 193                         usb_kill_urb(dev->interrupt_out_urb);
 194 }
 195
 196 /**
 197  *      ld_usb_delete
 198  */
 199 static void ld_usb_delete(struct ld_usb *dev)
 200 {
 201         ld_usb_abort_transfers(dev);
 202
 203         /* free data structures */
 204         usb_free_urb(dev->interrupt_in_urb);
 205         usb_free_urb(dev->interrupt_out_urb);
 206         kfree(dev->ring_buffer);
 207         kfree(dev->interrupt_in_buffer);
 208         kfree(dev->interrupt_out_buffer);
 209         kfree(dev);
 210 }
 211
 212 /**
 213  *      ld_usb_interrupt_in_callback
 214  */
 215 static void ld_usb_interrupt_in_callback(struct urb *urb)
 216 {
 217         struct ld_usb *dev = urb->context;
 218         size_t *actual_buffer;
 219         unsigned int next_ring_head;
 220         int status = urb->status;
 221         int retval;
 222
 223         if (status) {
 224                 if (status == -ENOENT ||
 225                     status == -ECONNRESET ||
 226                     status == -ESHUTDOWN) {
 227                         goto exit;
 228                 } else {
 229                         dbg_info(&dev->intf->dev, "%s: nonzero status received: %d\n",
 230                                  __func__, status);
 231                         spin_lock(&dev->rbsl);
 232                         goto resubmit; /* maybe we can recover */
 233                 }
 234         }
 235
 236         spin_lock(&dev->rbsl);
 237         if (urb->actual_length > 0) {
 238                 next_ring_head = (dev->ring_head+1) % ring_buffer_size;
 239                 if (next_ring_head != dev->ring_tail) {
 240                         actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_head*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
 241                         /* actual_buffer gets urb->actual_length + interrupt_in_buffer */
 242                         *actual_buffer = urb->actual_length;
 243                         memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length);
 244                         dev->ring_head = next_ring_head;
 245                         dbg_info(&dev->intf->dev, "%s: received %d bytes\n",
 246                                  __func__, urb->actual_length);
 247                 } else {
 248                         dev_warn(&dev->intf->dev,
 249                                  "Ring buffer overflow, %d bytes dropped\n",
 250                                  urb->actual_length);
 251                         dev->buffer_overflow = 1;
 252                 }
 253         }
 254
 255 resubmit:
 256         /* resubmit if we're still running */
 257         if (dev->interrupt_in_running && !dev->buffer_overflow && dev->intf) {
 258                 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC);
 259                 if (retval) {
 260                         dev_err(&dev->intf->dev,
 261                                 "usb_submit_urb failed (%d)\n", retval);
 262                         dev->buffer_overflow = 1;
 263                 }
 264         }
 265         spin_unlock(&dev->rbsl);
 266 exit:
 267         dev->interrupt_in_done = 1;
 268         wake_up_interruptible(&dev->read_wait);
 269 }
 270
 271 /**
 272  *      ld_usb_interrupt_out_callback
 273  */
 274 static void ld_usb_interrupt_out_callback(struct urb *urb)
 275 {
 276         struct ld_usb *dev = urb->context;
 277         int status = urb->status;
 278
 279         /* sync/async unlink faults aren't errors */
 280         if (status && !(status == -ENOENT ||
 281                         status == -ECONNRESET ||
 282                         status == -ESHUTDOWN))
 283                 dbg_info(&dev->intf->dev,
 284                          "%s - nonzero write interrupt status received: %d\n",
 285                          __func__, status);
 286
 287         dev->interrupt_out_busy = 0;
 288         wake_up_interruptible(&dev->write_wait);
 289 }
 290
 291 /**
 292  *      ld_usb_open
 293  */
 294 static int ld_usb_open(struct inode *inode, struct file *file)
 295 {
 296         struct ld_usb *dev;
 297         int subminor;
 298         int retval;
 299         struct usb_interface *interface;
 300
 301         nonseekable_open(inode, file);
 302         subminor = iminor(inode);
 303
 304         interface = usb_find_interface(&ld_usb_driver, subminor);
 305
 306         if (!interface) {
 307                 err("%s - error, can't find device for minor %d\n",
 308                      __func__, subminor);
 309                 return -ENODEV;
 310         }
 311
 312         dev = usb_get_intfdata(interface);
 313
 314         if (!dev)
 315                 return -ENODEV;
 316
 317         /* lock this device */
 318         if (mutex_lock_interruptible(&dev->mutex))
 319                 return -ERESTARTSYS;
 320
 321         /* allow opening only once */
 322         if (dev->open_count) {
 323                 retval = -EBUSY;
 324                 goto unlock_exit;
 325         }
 326         dev->open_count = 1;
 327
 328         /* initialize in direction */
 329         dev->ring_head = 0;
 330         dev->ring_tail = 0;
 331         dev->buffer_overflow = 0;
 332         usb_fill_int_urb(dev->interrupt_in_urb,
 333                          interface_to_usbdev(interface),
 334                          usb_rcvintpipe(interface_to_usbdev(interface),
 335                                         dev->interrupt_in_endpoint->bEndpointAddress),
 336                          dev->interrupt_in_buffer,
 337                          dev->interrupt_in_endpoint_size,
 338                          ld_usb_interrupt_in_callback,
 339                          dev,
 340                          dev->interrupt_in_interval);
 341
 342         dev->interrupt_in_running = 1;
 343         dev->interrupt_in_done = 0;
 344
 345         retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
 346         if (retval) {
 347                 dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval);
 348                 dev->interrupt_in_running = 0;
 349                 dev->open_count = 0;
 350                 goto unlock_exit;
 351         }
 352
 353         /* save device in the file's private structure */
 354         file->private_data = dev;
 355
 356 unlock_exit:
 357         mutex_unlock(&dev->mutex);
 358
 359         return retval;
 360 }
 361
 362 /**
 363  *      ld_usb_release
 364  */
 365 static int ld_usb_release(struct inode *inode, struct file *file)
 366 {
 367         struct ld_usb *dev;
 368         int retval = 0;
 369
 370         dev = file->private_data;
 371
 372         if (dev == NULL) {
 373                 retval = -ENODEV;
 374                 goto exit;
 375         }
 376
 377         if (mutex_lock_interruptible(&dev->mutex)) {
 378                 retval = -ERESTARTSYS;
 379                 goto exit;
 380         }
 381
 382         if (dev->open_count != 1) {
 383                 retval = -ENODEV;
 384                 goto unlock_exit;
 385         }
 386         if (dev->intf == NULL) {
 387                 /* the device was unplugged before the file was released */
 388                 mutex_unlock(&dev->mutex);
 389                 /* unlock here as ld_usb_delete frees dev */
 390                 ld_usb_delete(dev);
 391                 goto exit;
 392         }
 393
 394         /* wait until write transfer is finished */
 395         if (dev->interrupt_out_busy)
 396                 wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ);
 397         ld_usb_abort_transfers(dev);
 398         dev->open_count = 0;
 399
 400 unlock_exit:
 401         mutex_unlock(&dev->mutex);
 402
 403 exit:
 404         return retval;
 405 }
 406
 407 /**
 408  *      ld_usb_poll
 409  */
 410 static unsigned int ld_usb_poll(struct file *file, poll_table *wait)
 411 {
 412         struct ld_usb *dev;
 413         unsigned int mask = 0;
 414
 415         dev = file->private_data;
 416
 417         poll_wait(file, &dev->read_wait, wait);
 418         poll_wait(file, &dev->write_wait, wait);
 419
 420         if (dev->ring_head != dev->ring_tail)
 421                 mask |= POLLIN | POLLRDNORM;
 422         if (!dev->interrupt_out_busy)
 423                 mask |= POLLOUT | POLLWRNORM;
 424
 425         return mask;
 426 }
 427
 428 /**
 429  *      ld_usb_read
 430  */
 431 static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count,
 432                            loff_t *ppos)
 433 {
 434         struct ld_usb *dev;
 435         size_t *actual_buffer;
 436         size_t bytes_to_read;
 437         int retval = 0;
 438         int rv;
 439
 440         dev = file->private_data;
 441
 442         /* verify that we actually have some data to read */
 443         if (count == 0)
 444                 goto exit;
 445
 446         /* lock this object */
 447         if (mutex_lock_interruptible(&dev->mutex)) {
 448                 retval = -ERESTARTSYS;
 449                 goto exit;
 450         }
 451
 452         /* verify that the device wasn't unplugged */
 453         if (dev->intf == NULL) {
 454                 retval = -ENODEV;
 455                 err("No device or device unplugged %d\n", retval);
 456                 goto unlock_exit;
 457         }
 458
 459         /* wait for data */
 460         spin_lock_irq(&dev->rbsl);
 461         if (dev->ring_head == dev->ring_tail) {
 462                 dev->interrupt_in_done = 0;
 463                 spin_unlock_irq(&dev->rbsl);
 464                 if (file->f_flags & O_NONBLOCK) {
 465                         retval = -EAGAIN;
 466                         goto unlock_exit;
 467                 }
 468                 retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done);
 469                 if (retval < 0)
 470                         goto unlock_exit;
 471         } else {
 472                 spin_unlock_irq(&dev->rbsl);
 473         }
 474
 475         /* actual_buffer contains actual_length + interrupt_in_buffer */
 476         actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_tail*(sizeof(size_t)+dev->interrupt_in_endpoint_size));
 477         bytes_to_read = min(count, *actual_buffer);
 478         if (bytes_to_read < *actual_buffer)
 479                 dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n",
 480                          *actual_buffer-bytes_to_read);
 481
 482         /* copy one interrupt_in_buffer from ring_buffer into userspace */
 483         if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) {
 484                 retval = -EFAULT;
 485                 goto unlock_exit;
 486         }
 487         dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size;
 488
 489         retval = bytes_to_read;
 490
 491         spin_lock_irq(&dev->rbsl);
 492         if (dev->buffer_overflow) {
 493                 dev->buffer_overflow = 0;
 494                 spin_unlock_irq(&dev->rbsl);
 495                 rv = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL);
 496                 if (rv < 0)
 497                         dev->buffer_overflow = 1;
 498         } else {
 499                 spin_unlock_irq(&dev->rbsl);
 500         }
 501
 502 unlock_exit:
 503         /* unlock the device */
 504         mutex_unlock(&dev->mutex);
 505
 506 exit:
 507         return retval;
 508 }
 509
 510 /**
 511  *      ld_usb_write
 512  */
 513 static ssize_t ld_usb_write(struct file *file, const char __user *buffer,
 514                             size_t count, loff_t *ppos)
 515 {
 516         struct ld_usb *dev;
 517         size_t bytes_to_write;
 518         int retval = 0;
 519
 520         dev = file->private_data;
 521
 522         /* verify that we actually have some data to write */
 523         if (count == 0)
 524                 goto exit;
 525
 526         /* lock this object */
 527         if (mutex_lock_interruptible(&dev->mutex)) {
 528                 retval = -ERESTARTSYS;
 529                 goto exit;
 530         }
 531
 532         /* verify that the device wasn't unplugged */
 533         if (dev->intf == NULL) {
 534                 retval = -ENODEV;
 535                 err("No device or device unplugged %d\n", retval);
 536                 goto unlock_exit;
 537         }
 538
 539         /* wait until previous transfer is finished */
 540         if (dev->interrupt_out_busy) {
 541                 if (file->f_flags & O_NONBLOCK) {
 542                         retval = -EAGAIN;
 543                         goto unlock_exit;
 544                 }
 545                 retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy);
 546                 if (retval < 0) {
 547                         goto unlock_exit;
 548                 }
 549         }
 550
 551         /* write the data into interrupt_out_buffer from userspace */
 552         bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size);
 553         if (bytes_to_write < count)
 554                 dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n",count-bytes_to_write);
 555         dbg_info(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n", __func__, count, bytes_to_write);
 556
 557         if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) {
 558                 retval = -EFAULT;
 559                 goto unlock_exit;
 560         }
 561
 562         if (dev->interrupt_out_endpoint == NULL) {
 563                 /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */
 564                 retval = usb_control_msg(interface_to_usbdev(dev->intf),
 565                                          usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0),
 566                                          9,
 567                                          USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
 568                                          1 << 8, 0,
 569                                          dev->interrupt_out_buffer,
 570                                          bytes_to_write,
 571                                          USB_CTRL_SET_TIMEOUT * HZ);
 572                 if (retval < 0)
 573                         err("Couldn't submit HID_REQ_SET_REPORT %d\n", retval);
 574                 goto unlock_exit;
 575         }
 576
 577         /* send off the urb */
 578         usb_fill_int_urb(dev->interrupt_out_urb,
 579                          interface_to_usbdev(dev->intf),
 580                          usb_sndintpipe(interface_to_usbdev(dev->intf),
 581                                         dev->interrupt_out_endpoint->bEndpointAddress),
 582                          dev->interrupt_out_buffer,
 583                          bytes_to_write,
 584                          ld_usb_interrupt_out_callback,
 585                          dev,
 586                          dev->interrupt_out_interval);
 587
 588         dev->interrupt_out_busy = 1;
 589         wmb();
 590
 591         retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL);
 592         if (retval) {
 593                 dev->interrupt_out_busy = 0;
 594                 err("Couldn't submit interrupt_out_urb %d\n", retval);
 595                 goto unlock_exit;
 596         }
 597         retval = bytes_to_write;
 598
 599 unlock_exit:
 600         /* unlock the device */
 601         mutex_unlock(&dev->mutex);
 602
 603 exit:
 604         return retval;
 605 }
 606
 607 /* file operations needed when we register this driver */
 608 static const struct file_operations ld_usb_fops = {
 609         .owner =        THIS_MODULE,
 610         .read  =        ld_usb_read,
 611         .write =        ld_usb_write,
 612         .open =         ld_usb_open,
 613         .release =      ld_usb_release,
 614         .poll =         ld_usb_poll,
 615 };
 616
 617 /*
 618  * usb class driver info in order to get a minor number from the usb core,
 619  * and to have the device registered with the driver core
 620  */
 621 static struct usb_class_driver ld_usb_class = {
 622         .name =         "ldusb%d",
 623         .fops =         &ld_usb_fops,
 624         .minor_base =   USB_LD_MINOR_BASE,
 625 };
 626
 627 /**
 628  *      ld_usb_probe
 629  *
 630  *      Called by the usb core when a new device is connected that it thinks
 631  *      this driver might be interested in.
 632  */
 633 static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
 634 {
 635         struct usb_device *udev = interface_to_usbdev(intf);
 636         struct ld_usb *dev = NULL;
 637         struct usb_host_interface *iface_desc;
 638         struct usb_endpoint_descriptor *endpoint;
 639         char *buffer;
 640         int i;
 641         int retval = -ENOMEM;
 642
 643         /* allocate memory for our device state and intialize it */
 644
 645         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 646         if (dev == NULL) {
 647                 dev_err(&intf->dev, "Out of memory\n");
 648                 goto exit;
 649         }
 650         mutex_init(&dev->mutex);
 651         spin_lock_init(&dev->rbsl);
 652         dev->intf = intf;
 653         init_waitqueue_head(&dev->read_wait);
 654         init_waitqueue_head(&dev->write_wait);
 655
 656         /* workaround for early firmware versions on fast computers */
 657         if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) &&
 658             ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) ||
 659              (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) &&
 660             (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) {
 661                 buffer = kmalloc(256, GFP_KERNEL);
 662                 if (buffer == NULL) {
 663                         dev_err(&intf->dev, "Couldn't allocate string buffer\n");
 664                         goto error;
 665                 }
 666                 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */
 667                 usb_string(udev, 255, buffer, 256);
 668                 kfree(buffer);
 669         }
 670
 671         iface_desc = intf->cur_altsetting;
 672
 673         /* set up the endpoint information */
 674         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 675                 endpoint = &iface_desc->endpoint[i].desc;
 676
 677                 if (usb_endpoint_is_int_in(endpoint))
 678                         dev->interrupt_in_endpoint = endpoint;
 679
 680                 if (usb_endpoint_is_int_out(endpoint))
 681                         dev->interrupt_out_endpoint = endpoint;
 682         }
 683         if (dev->interrupt_in_endpoint == NULL) {
 684                 dev_err(&intf->dev, "Interrupt in endpoint not found\n");
 685                 goto error;
 686         }
 687         if (dev->interrupt_out_endpoint == NULL)
 688                 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n");
 689
 690         dev->interrupt_in_endpoint_size = le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize);
 691         dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL);
 692         if (!dev->ring_buffer) {
 693                 dev_err(&intf->dev, "Couldn't allocate ring_buffer\n");
 694                 goto error;
 695         }
 696         dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL);
 697         if (!dev->interrupt_in_buffer) {
 698                 dev_err(&intf->dev, "Couldn't allocate interrupt_in_buffer\n");
 699                 goto error;
 700         }
 701         dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
 702         if (!dev->interrupt_in_urb) {
 703                 dev_err(&intf->dev, "Couldn't allocate interrupt_in_urb\n");
 704                 goto error;
 705         }
 706         dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? le16_to_cpu(dev->interrupt_out_endpoint->wMaxPacketSize) :
 707                                                                          udev->descriptor.bMaxPacketSize0;
 708         dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL);
 709         if (!dev->interrupt_out_buffer) {
 710                 dev_err(&intf->dev, "Couldn't allocate interrupt_out_buffer\n");
 711                 goto error;
 712         }
 713         dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
 714         if (!dev->interrupt_out_urb) {
 715                 dev_err(&intf->dev, "Couldn't allocate interrupt_out_urb\n");
 716                 goto error;
 717         }
 718         dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval;
 719         if (dev->interrupt_out_endpoint)
 720                 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval;
 721
 722         /* we can register the device now, as it is ready */
 723         usb_set_intfdata(intf, dev);
 724
 725         retval = usb_register_dev(intf, &ld_usb_class);
 726         if (retval) {
 727                 /* something prevented us from registering this driver */
 728                 dev_err(&intf->dev, "Not able to get a minor for this device.\n");
 729                 usb_set_intfdata(intf, NULL);
 730                 goto error;
 731         }
 732
 733         /* let the user know what node this device is now attached to */
 734         dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n",
 735                 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor);
 736
 737 exit:
 738         return retval;
 739
 740 error:
 741         ld_usb_delete(dev);
 742
 743         return retval;
 744 }
 745
 746 /**
 747  *      ld_usb_disconnect
 748  *
 749  *      Called by the usb core when the device is removed from the system.
 750  */
 751 static void ld_usb_disconnect(struct usb_interface *intf)
 752 {
 753         struct ld_usb *dev;
 754         int minor;
 755
 756         dev = usb_get_intfdata(intf);
 757         usb_set_intfdata(intf, NULL);
 758
 759         minor = intf->minor;
 760
 761         /* give back our minor */
 762         usb_deregister_dev(intf, &ld_usb_class);
 763
 764         mutex_lock(&dev->mutex);
 765
 766         /* if the device is not opened, then we clean up right now */
 767         if (!dev->open_count) {
 768                 mutex_unlock(&dev->mutex);
 769                 ld_usb_delete(dev);
 770         } else {
 771                 dev->intf = NULL;
 772                 mutex_unlock(&dev->mutex);
 773         }
 774
 775         dev_info(&intf->dev, "LD USB Device #%d now disconnected\n",
 776                  (minor - USB_LD_MINOR_BASE));
 777 }
 778
 779 /* usb specific object needed to register this driver with the usb subsystem */
 780 static struct usb_driver ld_usb_driver = {
 781         .name =         "ldusb",
 782         .probe =        ld_usb_probe,
 783         .disconnect =   ld_usb_disconnect,
 784         .id_table =     ld_usb_table,
 785 };
 786
 787 /**
 788  *      ld_usb_init
 789  */
 790 static int __init ld_usb_init(void)
 791 {
 792         int retval;
 793
 794         /* register this driver with the USB subsystem */
 795         retval = usb_register(&ld_usb_driver);
 796         if (retval)
 797                 err("usb_register failed for the "__FILE__" driver. Error number %d\n", retval);
 798
 799         return retval;
 800 }
 801
 802 /**
 803  *      ld_usb_exit
 804  */
 805 static void __exit ld_usb_exit(void)
 806 {
 807         /* deregister this driver with the USB subsystem */
 808         usb_deregister(&ld_usb_driver);
 809 }
 810
 811 module_init(ld_usb_init);
 812 module_exit(ld_usb_exit);
 813