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 */ 75static 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}; 97MODULE_DEVICE_TABLE(usb, ld_usb_table); 98MODULE_VERSION("V0.13"); 99MODULE_AUTHOR("Michael Hund <mhund@ld-didactic.de>"); 100MODULE_DESCRIPTION("LD USB Driver"); 101MODULE_LICENSE("GPL"); 102MODULE_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 */ 114module_param(debug, int, S_IRUGO | S_IWUSR); 115MODULE_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 */ 120static int ring_buffer_size = 128; 121module_param(ring_buffer_size, int, 0); 122MODULE_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 */ 126static int write_buffer_size = 10; 127module_param(write_buffer_size, int, 0); 128MODULE_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 */ 139static int min_interrupt_in_interval = 2; 140module_param(min_interrupt_in_interval, int, 0); 141MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms"); 142 143static int min_interrupt_out_interval = 2; 144module_param(min_interrupt_out_interval, int, 0); 145MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms"); 146 147/* Structure to hold all of our device specific stuff */ 148struct 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() */ 180static DEFINE_MUTEX(disconnect_mutex); 181 182static struct usb_driver ld_usb_driver; 183 184/** 185 * ld_usb_abort_transfers 186 * aborts transfers and frees associated data structures 187 */ 188static 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 */ 204static 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 */ 220static 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 259resubmit: 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); 270exit: 271 dev->interrupt_in_done = 1; 272 wake_up_interruptible(&dev->read_wait); 273} 274 275/** 276 * ld_usb_interrupt_out_callback 277 */ 278static 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 */ 297static 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 366unlock_exit: 367 up(&dev->sem); 368 369unlock_disconnect_exit: 370 mutex_unlock(&disconnect_mutex); 371 372 return retval; 373} 374 375/** 376 * ld_usb_release 377 */ 378static 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 413unlock_exit: 414 up(&dev->sem); 415 416exit: 417 return retval; 418} 419 420/** 421 * ld_usb_poll 422 */ 423static 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 */ 444static 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 515unlock_exit: 516 /* unlock the device */ 517 up(&dev->sem); 518 519exit: 520 return retval; 521} 522 523/** 524 * ld_usb_write 525 */ 526static 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 612unlock_exit: 613 /* unlock the device */ 614 up(&dev->sem); 615 616exit: 617 return retval; 618} 619 620/* file operations needed when we register this driver */ 621static 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 */ 634static 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 */ 646static 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 if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) && 670 ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) || 671 (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) && 672 (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) { 673 buffer = kmalloc(256, GFP_KERNEL); 674 if (buffer == NULL) { 675 dev_err(&intf->dev, "Couldn't allocate string buffer\n"); 676 goto error; 677 } 678 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */ 679 usb_string(udev, 255, buffer, 256); 680 kfree(buffer); 681 } 682 683 iface_desc = intf->cur_altsetting; 684 685 /* set up the endpoint information */ 686 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) { 687 endpoint = &iface_desc->endpoint[i].desc; 688 689 if (usb_endpoint_is_int_in(endpoint)) 690 dev->interrupt_in_endpoint = endpoint; 691 692 if (usb_endpoint_is_int_out(endpoint)) 693 dev->interrupt_out_endpoint = endpoint; 694 } 695 if (dev->interrupt_in_endpoint == NULL) { 696 dev_err(&intf->dev, "Interrupt in endpoint not found\n"); 697 goto error; 698 } 699 if (dev->interrupt_out_endpoint == NULL) 700 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n"); 701 702 dev->interrupt_in_endpoint_size = le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize); 703 dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL); 704 if (!dev->ring_buffer) { 705 dev_err(&intf->dev, "Couldn't allocate ring_buffer\n"); 706 goto error; 707 } 708 dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL); 709 if (!dev->interrupt_in_buffer) { 710 dev_err(&intf->dev, "Couldn't allocate interrupt_in_buffer\n"); 711 goto error; 712 } 713 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL); 714 if (!dev->interrupt_in_urb) { 715 dev_err(&intf->dev, "Couldn't allocate interrupt_in_urb\n"); 716 goto error; 717 } 718 dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? le16_to_cpu(dev->interrupt_out_endpoint->wMaxPacketSize) : 719 udev->descriptor.bMaxPacketSize0; 720 dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL); 721 if (!dev->interrupt_out_buffer) { 722 dev_err(&intf->dev, "Couldn't allocate interrupt_out_buffer\n"); 723 goto error; 724 } 725 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL); 726 if (!dev->interrupt_out_urb) { 727 dev_err(&intf->dev, "Couldn't allocate interrupt_out_urb\n"); 728 goto error; 729 } 730 dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval; 731 if (dev->interrupt_out_endpoint) 732 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval; 733 734 /* we can register the device now, as it is ready */ 735 usb_set_intfdata(intf, dev); 736 737 retval = usb_register_dev(intf, &ld_usb_class); 738 if (retval) { 739 /* something prevented us from registering this driver */ 740 dev_err(&intf->dev, "Not able to get a minor for this device.\n"); 741 usb_set_intfdata(intf, NULL); 742 goto error; 743 } 744 745 /* let the user know what node this device is now attached to */ 746 dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n", 747 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor); 748 749exit: 750 return retval; 751 752error: 753 ld_usb_delete(dev); 754 755 return retval; 756} 757 758/** 759 * ld_usb_disconnect 760 * 761 * Called by the usb core when the device is removed from the system. 762 */ 763static void ld_usb_disconnect(struct usb_interface *intf) 764{ 765 struct ld_usb *dev; 766 int minor; 767 768 mutex_lock(&disconnect_mutex); 769 770 dev = usb_get_intfdata(intf); 771 usb_set_intfdata(intf, NULL); 772 773 down(&dev->sem); 774 775 minor = intf->minor; 776 777 /* give back our minor */ 778 usb_deregister_dev(intf, &ld_usb_class); 779 780 /* if the device is not opened, then we clean up right now */ 781 if (!dev->open_count) { 782 up(&dev->sem); 783 ld_usb_delete(dev); 784 } else { 785 dev->intf = NULL; 786 up(&dev->sem); 787 } 788 789 mutex_unlock(&disconnect_mutex); 790 791 dev_info(&intf->dev, "LD USB Device #%d now disconnected\n", 792 (minor - USB_LD_MINOR_BASE)); 793} 794 795/* usb specific object needed to register this driver with the usb subsystem */ 796static struct usb_driver ld_usb_driver = { 797 .name = "ldusb", 798 .probe = ld_usb_probe, 799 .disconnect = ld_usb_disconnect, 800 .id_table = ld_usb_table, 801}; 802 803/** 804 * ld_usb_init 805 */ 806static int __init ld_usb_init(void) 807{ 808 int retval; 809 810 /* register this driver with the USB subsystem */ 811 retval = usb_register(&ld_usb_driver); 812 if (retval) 813 err("usb_register failed for the "__FILE__" driver. Error number %d\n", retval); 814 815 return retval; 816} 817 818/** 819 * ld_usb_exit 820 */ 821static void __exit ld_usb_exit(void) 822{ 823 /* deregister this driver with the USB subsystem */ 824 usb_deregister(&ld_usb_driver); 825} 826 827module_init(ld_usb_init); 828module_exit(ld_usb_exit); 829