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 25#include <linux/kernel.h> 26#include <linux/errno.h> 27#include <linux/init.h> 28#include <linux/slab.h> 29#include <linux/module.h> 30#include <linux/mutex.h> 31 32#include <asm/uaccess.h> 33#include <linux/input.h> 34#include <linux/usb.h> 35#include <linux/poll.h> 36 37/* Define these values to match your devices */ 38#define USB_VENDOR_ID_LD 0x0f11 /* USB Vendor ID of LD Didactic GmbH */ 39#define USB_DEVICE_ID_LD_CASSY 0x1000 /* USB Product ID of CASSY-S modules with 8 bytes endpoint size */ 40#define USB_DEVICE_ID_LD_CASSY2 0x1001 /* USB Product ID of CASSY-S modules with 64 bytes endpoint size */ 41#define USB_DEVICE_ID_LD_POCKETCASSY 0x1010 /* USB Product ID of Pocket-CASSY */ 42#define USB_DEVICE_ID_LD_POCKETCASSY2 0x1011 /* USB Product ID of Pocket-CASSY 2 (reserved) */ 43#define USB_DEVICE_ID_LD_MOBILECASSY 0x1020 /* USB Product ID of Mobile-CASSY */ 44#define USB_DEVICE_ID_LD_MOBILECASSY2 0x1021 /* USB Product ID of Mobile-CASSY 2 (reserved) */ 45#define USB_DEVICE_ID_LD_MICROCASSYVOLTAGE 0x1031 /* USB Product ID of Micro-CASSY Voltage */ 46#define USB_DEVICE_ID_LD_MICROCASSYCURRENT 0x1032 /* USB Product ID of Micro-CASSY Current */ 47#define USB_DEVICE_ID_LD_MICROCASSYTIME 0x1033 /* USB Product ID of Micro-CASSY Time (reserved) */ 48#define USB_DEVICE_ID_LD_MICROCASSYTEMPERATURE 0x1035 /* USB Product ID of Micro-CASSY Temperature */ 49#define USB_DEVICE_ID_LD_MICROCASSYPH 0x1038 /* USB Product ID of Micro-CASSY pH */ 50#define USB_DEVICE_ID_LD_JWM 0x1080 /* USB Product ID of Joule and Wattmeter */ 51#define USB_DEVICE_ID_LD_DMMP 0x1081 /* USB Product ID of Digital Multimeter P (reserved) */ 52#define USB_DEVICE_ID_LD_UMIP 0x1090 /* USB Product ID of UMI P */ 53#define USB_DEVICE_ID_LD_UMIC 0x10A0 /* USB Product ID of UMI C */ 54#define USB_DEVICE_ID_LD_UMIB 0x10B0 /* USB Product ID of UMI B */ 55#define USB_DEVICE_ID_LD_XRAY 0x1100 /* USB Product ID of X-Ray Apparatus 55481 */ 56#define USB_DEVICE_ID_LD_XRAY2 0x1101 /* USB Product ID of X-Ray Apparatus 554800 */ 57#define USB_DEVICE_ID_LD_XRAYCT 0x1110 /* USB Product ID of X-Ray Apparatus CT 554821*/ 58#define USB_DEVICE_ID_LD_VIDEOCOM 0x1200 /* USB Product ID of VideoCom */ 59#define USB_DEVICE_ID_LD_MOTOR 0x1210 /* USB Product ID of Motor (reserved) */ 60#define USB_DEVICE_ID_LD_COM3LAB 0x2000 /* USB Product ID of COM3LAB */ 61#define USB_DEVICE_ID_LD_TELEPORT 0x2010 /* USB Product ID of Terminal Adapter */ 62#define USB_DEVICE_ID_LD_NETWORKANALYSER 0x2020 /* USB Product ID of Network Analyser */ 63#define USB_DEVICE_ID_LD_POWERCONTROL 0x2030 /* USB Product ID of Converter Control Unit */ 64#define USB_DEVICE_ID_LD_MACHINETEST 0x2040 /* USB Product ID of Machine Test System */ 65#define USB_DEVICE_ID_LD_MOSTANALYSER 0x2050 /* USB Product ID of MOST Protocol Analyser */ 66#define USB_DEVICE_ID_LD_MOSTANALYSER2 0x2051 /* USB Product ID of MOST Protocol Analyser 2 */ 67#define USB_DEVICE_ID_LD_ABSESP 0x2060 /* USB Product ID of ABS ESP */ 68#define USB_DEVICE_ID_LD_AUTODATABUS 0x2070 /* USB Product ID of Automotive Data Buses */ 69#define USB_DEVICE_ID_LD_MCT 0x2080 /* USB Product ID of Microcontroller technique */ 70#define USB_DEVICE_ID_LD_HYBRID 0x2090 /* USB Product ID of Automotive Hybrid */ 71#define USB_DEVICE_ID_LD_HEATCONTROL 0x20A0 /* USB Product ID of Heat control */ 72 73#define USB_VENDOR_ID_VERNIER 0x08f7 74#define USB_DEVICE_ID_VERNIER_GOTEMP 0x0002 75#define USB_DEVICE_ID_VERNIER_SKIP 0x0003 76#define USB_DEVICE_ID_VERNIER_CYCLOPS 0x0004 77#define USB_DEVICE_ID_VERNIER_LCSPEC 0x0006 78 79#ifdef CONFIG_USB_DYNAMIC_MINORS 80#define USB_LD_MINOR_BASE 0 81#else 82#define USB_LD_MINOR_BASE 176 83#endif 84 85/* table of devices that work with this driver */ 86static const struct usb_device_id ld_usb_table[] = { 87 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY) }, 88 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY2) }, 89 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY) }, 90 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY2) }, 91 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY) }, 92 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY2) }, 93 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYVOLTAGE) }, 94 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYCURRENT) }, 95 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYTIME) }, 96 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYTEMPERATURE) }, 97 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MICROCASSYPH) }, 98 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_JWM) }, 99 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_DMMP) }, 100 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIP) }, 101 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIC) }, 102 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIB) }, 103 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY) }, 104 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY2) }, 105 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_VIDEOCOM) }, 106 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOTOR) }, 107 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_COM3LAB) }, 108 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_TELEPORT) }, 109 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_NETWORKANALYSER) }, 110 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POWERCONTROL) }, 111 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MACHINETEST) }, 112 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOSTANALYSER) }, 113 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOSTANALYSER2) }, 114 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_ABSESP) }, 115 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_AUTODATABUS) }, 116 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MCT) }, 117 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_HYBRID) }, 118 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_HEATCONTROL) }, 119 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_GOTEMP) }, 120 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_SKIP) }, 121 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_CYCLOPS) }, 122 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_LCSPEC) }, 123 { } /* Terminating entry */ 124}; 125MODULE_DEVICE_TABLE(usb, ld_usb_table); 126MODULE_VERSION("V0.14"); 127MODULE_AUTHOR("Michael Hund <mhund@ld-didactic.de>"); 128MODULE_DESCRIPTION("LD USB Driver"); 129MODULE_LICENSE("GPL"); 130MODULE_SUPPORTED_DEVICE("LD USB Devices"); 131 132#ifdef CONFIG_USB_DEBUG 133 static int debug = 1; 134#else 135 static int debug = 0; 136#endif 137 138/* Use our own dbg macro */ 139#define dbg_info(dev, format, arg...) do { if (debug) dev_info(dev , format , ## arg); } while (0) 140 141/* Module parameters */ 142module_param(debug, int, S_IRUGO | S_IWUSR); 143MODULE_PARM_DESC(debug, "Debug enabled or not"); 144 145/* All interrupt in transfers are collected in a ring buffer to 146 * avoid racing conditions and get better performance of the driver. 147 */ 148static int ring_buffer_size = 128; 149module_param(ring_buffer_size, int, 0); 150MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size in reports"); 151 152/* The write_buffer can contain more than one interrupt out transfer. 153 */ 154static int write_buffer_size = 10; 155module_param(write_buffer_size, int, 0); 156MODULE_PARM_DESC(write_buffer_size, "Write buffer size in reports"); 157 158/* As of kernel version 2.6.4 ehci-hcd uses an 159 * "only one interrupt transfer per frame" shortcut 160 * to simplify the scheduling of periodic transfers. 161 * This conflicts with our standard 1ms intervals for in and out URBs. 162 * We use default intervals of 2ms for in and 2ms for out transfers, 163 * which should be fast enough. 164 * Increase the interval to allow more devices that do interrupt transfers, 165 * or set to 1 to use the standard interval from the endpoint descriptors. 166 */ 167static int min_interrupt_in_interval = 2; 168module_param(min_interrupt_in_interval, int, 0); 169MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms"); 170 171static int min_interrupt_out_interval = 2; 172module_param(min_interrupt_out_interval, int, 0); 173MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms"); 174 175/* Structure to hold all of our device specific stuff */ 176struct ld_usb { 177 struct mutex mutex; /* locks this structure */ 178 struct usb_interface* intf; /* save off the usb interface pointer */ 179 180 int open_count; /* number of times this port has been opened */ 181 182 char* ring_buffer; 183 unsigned int ring_head; 184 unsigned int ring_tail; 185 186 wait_queue_head_t read_wait; 187 wait_queue_head_t write_wait; 188 189 char* interrupt_in_buffer; 190 struct usb_endpoint_descriptor* interrupt_in_endpoint; 191 struct urb* interrupt_in_urb; 192 int interrupt_in_interval; 193 size_t interrupt_in_endpoint_size; 194 int interrupt_in_running; 195 int interrupt_in_done; 196 int buffer_overflow; 197 spinlock_t rbsl; 198 199 char* interrupt_out_buffer; 200 struct usb_endpoint_descriptor* interrupt_out_endpoint; 201 struct urb* interrupt_out_urb; 202 int interrupt_out_interval; 203 size_t interrupt_out_endpoint_size; 204 int interrupt_out_busy; 205}; 206 207static struct usb_driver ld_usb_driver; 208 209/** 210 * ld_usb_abort_transfers 211 * aborts transfers and frees associated data structures 212 */ 213static void ld_usb_abort_transfers(struct ld_usb *dev) 214{ 215 /* shutdown transfer */ 216 if (dev->interrupt_in_running) { 217 dev->interrupt_in_running = 0; 218 if (dev->intf) 219 usb_kill_urb(dev->interrupt_in_urb); 220 } 221 if (dev->interrupt_out_busy) 222 if (dev->intf) 223 usb_kill_urb(dev->interrupt_out_urb); 224} 225 226/** 227 * ld_usb_delete 228 */ 229static void ld_usb_delete(struct ld_usb *dev) 230{ 231 ld_usb_abort_transfers(dev); 232 233 /* free data structures */ 234 usb_free_urb(dev->interrupt_in_urb); 235 usb_free_urb(dev->interrupt_out_urb); 236 kfree(dev->ring_buffer); 237 kfree(dev->interrupt_in_buffer); 238 kfree(dev->interrupt_out_buffer); 239 kfree(dev); 240} 241 242/** 243 * ld_usb_interrupt_in_callback 244 */ 245static void ld_usb_interrupt_in_callback(struct urb *urb) 246{ 247 struct ld_usb *dev = urb->context; 248 size_t *actual_buffer; 249 unsigned int next_ring_head; 250 int status = urb->status; 251 int retval; 252 253 if (status) { 254 if (status == -ENOENT || 255 status == -ECONNRESET || 256 status == -ESHUTDOWN) { 257 goto exit; 258 } else { 259 dbg_info(&dev->intf->dev, "%s: nonzero status received: %d\n", 260 __func__, status); 261 spin_lock(&dev->rbsl); 262 goto resubmit; /* maybe we can recover */ 263 } 264 } 265 266 spin_lock(&dev->rbsl); 267 if (urb->actual_length > 0) { 268 next_ring_head = (dev->ring_head+1) % ring_buffer_size; 269 if (next_ring_head != dev->ring_tail) { 270 actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_head*(sizeof(size_t)+dev->interrupt_in_endpoint_size)); 271 /* actual_buffer gets urb->actual_length + interrupt_in_buffer */ 272 *actual_buffer = urb->actual_length; 273 memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length); 274 dev->ring_head = next_ring_head; 275 dbg_info(&dev->intf->dev, "%s: received %d bytes\n", 276 __func__, urb->actual_length); 277 } else { 278 dev_warn(&dev->intf->dev, 279 "Ring buffer overflow, %d bytes dropped\n", 280 urb->actual_length); 281 dev->buffer_overflow = 1; 282 } 283 } 284 285resubmit: 286 /* resubmit if we're still running */ 287 if (dev->interrupt_in_running && !dev->buffer_overflow && dev->intf) { 288 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC); 289 if (retval) { 290 dev_err(&dev->intf->dev, 291 "usb_submit_urb failed (%d)\n", retval); 292 dev->buffer_overflow = 1; 293 } 294 } 295 spin_unlock(&dev->rbsl); 296exit: 297 dev->interrupt_in_done = 1; 298 wake_up_interruptible(&dev->read_wait); 299} 300 301/** 302 * ld_usb_interrupt_out_callback 303 */ 304static void ld_usb_interrupt_out_callback(struct urb *urb) 305{ 306 struct ld_usb *dev = urb->context; 307 int status = urb->status; 308 309 /* sync/async unlink faults aren't errors */ 310 if (status && !(status == -ENOENT || 311 status == -ECONNRESET || 312 status == -ESHUTDOWN)) 313 dbg_info(&dev->intf->dev, 314 "%s - nonzero write interrupt status received: %d\n", 315 __func__, status); 316 317 dev->interrupt_out_busy = 0; 318 wake_up_interruptible(&dev->write_wait); 319} 320 321/** 322 * ld_usb_open 323 */ 324static int ld_usb_open(struct inode *inode, struct file *file) 325{ 326 struct ld_usb *dev; 327 int subminor; 328 int retval; 329 struct usb_interface *interface; 330 331 nonseekable_open(inode, file); 332 subminor = iminor(inode); 333 334 interface = usb_find_interface(&ld_usb_driver, subminor); 335 336 if (!interface) { 337 err("%s - error, can't find device for minor %d\n", 338 __func__, subminor); 339 return -ENODEV; 340 } 341 342 dev = usb_get_intfdata(interface); 343 344 if (!dev) 345 return -ENODEV; 346 347 /* lock this device */ 348 if (mutex_lock_interruptible(&dev->mutex)) 349 return -ERESTARTSYS; 350 351 /* allow opening only once */ 352 if (dev->open_count) { 353 retval = -EBUSY; 354 goto unlock_exit; 355 } 356 dev->open_count = 1; 357 358 /* initialize in direction */ 359 dev->ring_head = 0; 360 dev->ring_tail = 0; 361 dev->buffer_overflow = 0; 362 usb_fill_int_urb(dev->interrupt_in_urb, 363 interface_to_usbdev(interface), 364 usb_rcvintpipe(interface_to_usbdev(interface), 365 dev->interrupt_in_endpoint->bEndpointAddress), 366 dev->interrupt_in_buffer, 367 dev->interrupt_in_endpoint_size, 368 ld_usb_interrupt_in_callback, 369 dev, 370 dev->interrupt_in_interval); 371 372 dev->interrupt_in_running = 1; 373 dev->interrupt_in_done = 0; 374 375 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 376 if (retval) { 377 dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval); 378 dev->interrupt_in_running = 0; 379 dev->open_count = 0; 380 goto unlock_exit; 381 } 382 383 /* save device in the file's private structure */ 384 file->private_data = dev; 385 386unlock_exit: 387 mutex_unlock(&dev->mutex); 388 389 return retval; 390} 391 392/** 393 * ld_usb_release 394 */ 395static int ld_usb_release(struct inode *inode, struct file *file) 396{ 397 struct ld_usb *dev; 398 int retval = 0; 399 400 dev = file->private_data; 401 402 if (dev == NULL) { 403 retval = -ENODEV; 404 goto exit; 405 } 406 407 if (mutex_lock_interruptible(&dev->mutex)) { 408 retval = -ERESTARTSYS; 409 goto exit; 410 } 411 412 if (dev->open_count != 1) { 413 retval = -ENODEV; 414 goto unlock_exit; 415 } 416 if (dev->intf == NULL) { 417 /* the device was unplugged before the file was released */ 418 mutex_unlock(&dev->mutex); 419 /* unlock here as ld_usb_delete frees dev */ 420 ld_usb_delete(dev); 421 goto exit; 422 } 423 424 /* wait until write transfer is finished */ 425 if (dev->interrupt_out_busy) 426 wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ); 427 ld_usb_abort_transfers(dev); 428 dev->open_count = 0; 429 430unlock_exit: 431 mutex_unlock(&dev->mutex); 432 433exit: 434 return retval; 435} 436 437/** 438 * ld_usb_poll 439 */ 440static unsigned int ld_usb_poll(struct file *file, poll_table *wait) 441{ 442 struct ld_usb *dev; 443 unsigned int mask = 0; 444 445 dev = file->private_data; 446 447 if (!dev->intf) 448 return POLLERR | POLLHUP; 449 450 poll_wait(file, &dev->read_wait, wait); 451 poll_wait(file, &dev->write_wait, wait); 452 453 if (dev->ring_head != dev->ring_tail) 454 mask |= POLLIN | POLLRDNORM; 455 if (!dev->interrupt_out_busy) 456 mask |= POLLOUT | POLLWRNORM; 457 458 return mask; 459} 460 461/** 462 * ld_usb_read 463 */ 464static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count, 465 loff_t *ppos) 466{ 467 struct ld_usb *dev; 468 size_t *actual_buffer; 469 size_t bytes_to_read; 470 int retval = 0; 471 int rv; 472 473 dev = file->private_data; 474 475 /* verify that we actually have some data to read */ 476 if (count == 0) 477 goto exit; 478 479 /* lock this object */ 480 if (mutex_lock_interruptible(&dev->mutex)) { 481 retval = -ERESTARTSYS; 482 goto exit; 483 } 484 485 /* verify that the device wasn't unplugged */ 486 if (dev->intf == NULL) { 487 retval = -ENODEV; 488 err("No device or device unplugged %d\n", retval); 489 goto unlock_exit; 490 } 491 492 /* wait for data */ 493 spin_lock_irq(&dev->rbsl); 494 if (dev->ring_head == dev->ring_tail) { 495 dev->interrupt_in_done = 0; 496 spin_unlock_irq(&dev->rbsl); 497 if (file->f_flags & O_NONBLOCK) { 498 retval = -EAGAIN; 499 goto unlock_exit; 500 } 501 retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done); 502 if (retval < 0) 503 goto unlock_exit; 504 } else { 505 spin_unlock_irq(&dev->rbsl); 506 } 507 508 /* actual_buffer contains actual_length + interrupt_in_buffer */ 509 actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_tail*(sizeof(size_t)+dev->interrupt_in_endpoint_size)); 510 bytes_to_read = min(count, *actual_buffer); 511 if (bytes_to_read < *actual_buffer) 512 dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n", 513 *actual_buffer-bytes_to_read); 514 515 /* copy one interrupt_in_buffer from ring_buffer into userspace */ 516 if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) { 517 retval = -EFAULT; 518 goto unlock_exit; 519 } 520 dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size; 521 522 retval = bytes_to_read; 523 524 spin_lock_irq(&dev->rbsl); 525 if (dev->buffer_overflow) { 526 dev->buffer_overflow = 0; 527 spin_unlock_irq(&dev->rbsl); 528 rv = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 529 if (rv < 0) 530 dev->buffer_overflow = 1; 531 } else { 532 spin_unlock_irq(&dev->rbsl); 533 } 534 535unlock_exit: 536 /* unlock the device */ 537 mutex_unlock(&dev->mutex); 538 539exit: 540 return retval; 541} 542 543/** 544 * ld_usb_write 545 */ 546static ssize_t ld_usb_write(struct file *file, const char __user *buffer, 547 size_t count, loff_t *ppos) 548{ 549 struct ld_usb *dev; 550 size_t bytes_to_write; 551 int retval = 0; 552 553 dev = file->private_data; 554 555 /* verify that we actually have some data to write */ 556 if (count == 0) 557 goto exit; 558 559 /* lock this object */ 560 if (mutex_lock_interruptible(&dev->mutex)) { 561 retval = -ERESTARTSYS; 562 goto exit; 563 } 564 565 /* verify that the device wasn't unplugged */ 566 if (dev->intf == NULL) { 567 retval = -ENODEV; 568 err("No device or device unplugged %d\n", retval); 569 goto unlock_exit; 570 } 571 572 /* wait until previous transfer is finished */ 573 if (dev->interrupt_out_busy) { 574 if (file->f_flags & O_NONBLOCK) { 575 retval = -EAGAIN; 576 goto unlock_exit; 577 } 578 retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy); 579 if (retval < 0) { 580 goto unlock_exit; 581 } 582 } 583 584 /* write the data into interrupt_out_buffer from userspace */ 585 bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size); 586 if (bytes_to_write < count) 587 dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n",count-bytes_to_write); 588 dbg_info(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n", __func__, count, bytes_to_write); 589 590 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) { 591 retval = -EFAULT; 592 goto unlock_exit; 593 } 594 595 if (dev->interrupt_out_endpoint == NULL) { 596 /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */ 597 retval = usb_control_msg(interface_to_usbdev(dev->intf), 598 usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0), 599 9, 600 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT, 601 1 << 8, 0, 602 dev->interrupt_out_buffer, 603 bytes_to_write, 604 USB_CTRL_SET_TIMEOUT * HZ); 605 if (retval < 0) 606 err("Couldn't submit HID_REQ_SET_REPORT %d\n", retval); 607 goto unlock_exit; 608 } 609 610 /* send off the urb */ 611 usb_fill_int_urb(dev->interrupt_out_urb, 612 interface_to_usbdev(dev->intf), 613 usb_sndintpipe(interface_to_usbdev(dev->intf), 614 dev->interrupt_out_endpoint->bEndpointAddress), 615 dev->interrupt_out_buffer, 616 bytes_to_write, 617 ld_usb_interrupt_out_callback, 618 dev, 619 dev->interrupt_out_interval); 620 621 dev->interrupt_out_busy = 1; 622 wmb(); 623 624 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL); 625 if (retval) { 626 dev->interrupt_out_busy = 0; 627 err("Couldn't submit interrupt_out_urb %d\n", retval); 628 goto unlock_exit; 629 } 630 retval = bytes_to_write; 631 632unlock_exit: 633 /* unlock the device */ 634 mutex_unlock(&dev->mutex); 635 636exit: 637 return retval; 638} 639 640/* file operations needed when we register this driver */ 641static const struct file_operations ld_usb_fops = { 642 .owner = THIS_MODULE, 643 .read = ld_usb_read, 644 .write = ld_usb_write, 645 .open = ld_usb_open, 646 .release = ld_usb_release, 647 .poll = ld_usb_poll, 648 .llseek = no_llseek, 649}; 650 651/* 652 * usb class driver info in order to get a minor number from the usb core, 653 * and to have the device registered with the driver core 654 */ 655static struct usb_class_driver ld_usb_class = { 656 .name = "ldusb%d", 657 .fops = &ld_usb_fops, 658 .minor_base = USB_LD_MINOR_BASE, 659}; 660 661/** 662 * ld_usb_probe 663 * 664 * Called by the usb core when a new device is connected that it thinks 665 * this driver might be interested in. 666 */ 667static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id) 668{ 669 struct usb_device *udev = interface_to_usbdev(intf); 670 struct ld_usb *dev = NULL; 671 struct usb_host_interface *iface_desc; 672 struct usb_endpoint_descriptor *endpoint; 673 char *buffer; 674 int i; 675 int retval = -ENOMEM; 676 677 /* allocate memory for our device state and initialize it */ 678 679 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 680 if (dev == NULL) { 681 dev_err(&intf->dev, "Out of memory\n"); 682 goto exit; 683 } 684 mutex_init(&dev->mutex); 685 spin_lock_init(&dev->rbsl); 686 dev->intf = intf; 687 init_waitqueue_head(&dev->read_wait); 688 init_waitqueue_head(&dev->write_wait); 689 690 /* workaround for early firmware versions on fast computers */ 691 if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) && 692 ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) || 693 (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) && 694 (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) { 695 buffer = kmalloc(256, GFP_KERNEL); 696 if (buffer == NULL) { 697 dev_err(&intf->dev, "Couldn't allocate string buffer\n"); 698 goto error; 699 } 700 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */ 701 usb_string(udev, 255, buffer, 256); 702 kfree(buffer); 703 } 704 705 iface_desc = intf->cur_altsetting; 706 707 /* set up the endpoint information */ 708 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) { 709 endpoint = &iface_desc->endpoint[i].desc; 710 711 if (usb_endpoint_is_int_in(endpoint)) 712 dev->interrupt_in_endpoint = endpoint; 713 714 if (usb_endpoint_is_int_out(endpoint)) 715 dev->interrupt_out_endpoint = endpoint; 716 } 717 if (dev->interrupt_in_endpoint == NULL) { 718 dev_err(&intf->dev, "Interrupt in endpoint not found\n"); 719 goto error; 720 } 721 if (dev->interrupt_out_endpoint == NULL) 722 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n"); 723 724 dev->interrupt_in_endpoint_size = usb_endpoint_maxp(dev->interrupt_in_endpoint); 725 dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL); 726 if (!dev->ring_buffer) { 727 dev_err(&intf->dev, "Couldn't allocate ring_buffer\n"); 728 goto error; 729 } 730 dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL); 731 if (!dev->interrupt_in_buffer) { 732 dev_err(&intf->dev, "Couldn't allocate interrupt_in_buffer\n"); 733 goto error; 734 } 735 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL); 736 if (!dev->interrupt_in_urb) { 737 dev_err(&intf->dev, "Couldn't allocate interrupt_in_urb\n"); 738 goto error; 739 } 740 dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? usb_endpoint_maxp(dev->interrupt_out_endpoint) : 741 udev->descriptor.bMaxPacketSize0; 742 dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL); 743 if (!dev->interrupt_out_buffer) { 744 dev_err(&intf->dev, "Couldn't allocate interrupt_out_buffer\n"); 745 goto error; 746 } 747 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL); 748 if (!dev->interrupt_out_urb) { 749 dev_err(&intf->dev, "Couldn't allocate interrupt_out_urb\n"); 750 goto error; 751 } 752 dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval; 753 if (dev->interrupt_out_endpoint) 754 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval; 755 756 /* we can register the device now, as it is ready */ 757 usb_set_intfdata(intf, dev); 758 759 retval = usb_register_dev(intf, &ld_usb_class); 760 if (retval) { 761 /* something prevented us from registering this driver */ 762 dev_err(&intf->dev, "Not able to get a minor for this device.\n"); 763 usb_set_intfdata(intf, NULL); 764 goto error; 765 } 766 767 /* let the user know what node this device is now attached to */ 768 dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n", 769 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor); 770 771exit: 772 return retval; 773 774error: 775 ld_usb_delete(dev); 776 777 return retval; 778} 779 780/** 781 * ld_usb_disconnect 782 * 783 * Called by the usb core when the device is removed from the system. 784 */ 785static void ld_usb_disconnect(struct usb_interface *intf) 786{ 787 struct ld_usb *dev; 788 int minor; 789 790 dev = usb_get_intfdata(intf); 791 usb_set_intfdata(intf, NULL); 792 793 minor = intf->minor; 794 795 /* give back our minor */ 796 usb_deregister_dev(intf, &ld_usb_class); 797 798 mutex_lock(&dev->mutex); 799 800 /* if the device is not opened, then we clean up right now */ 801 if (!dev->open_count) { 802 mutex_unlock(&dev->mutex); 803 ld_usb_delete(dev); 804 } else { 805 dev->intf = NULL; 806 /* wake up pollers */ 807 wake_up_interruptible_all(&dev->read_wait); 808 wake_up_interruptible_all(&dev->write_wait); 809 mutex_unlock(&dev->mutex); 810 } 811 812 dev_info(&intf->dev, "LD USB Device #%d now disconnected\n", 813 (minor - USB_LD_MINOR_BASE)); 814} 815 816/* usb specific object needed to register this driver with the usb subsystem */ 817static struct usb_driver ld_usb_driver = { 818 .name = "ldusb", 819 .probe = ld_usb_probe, 820 .disconnect = ld_usb_disconnect, 821 .id_table = ld_usb_table, 822}; 823 824module_usb_driver(ld_usb_driver); 825 826