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 #define USB_VENDOR_ID_MICROCHIP 0x04d8 67 #define USB_DEVICE_ID_PICDEM 0x000c 68 69 #ifdef CONFIG_USB_DYNAMIC_MINORS 70 #define USB_LD_MINOR_BASE 0 71 #else 72 #define USB_LD_MINOR_BASE 176 73 #endif 74 75 /* table of devices that work with this driver */ 76 static struct usb_device_id ld_usb_table [] = { 77 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY) }, 78 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY) }, 79 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY) }, 80 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_JWM) }, 81 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_DMMP) }, 82 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIP) }, 83 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY1) }, 84 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY2) }, 85 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_VIDEOCOM) }, 86 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_COM3LAB) }, 87 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_TELEPORT) }, 88 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_NETWORKANALYSER) }, 89 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POWERCONTROL) }, 90 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MACHINETEST) }, 91 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_LABPRO) }, 92 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_GOTEMP) }, 93 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_SKIP) }, 94 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_CYCLOPS) }, 95 { USB_DEVICE(USB_VENDOR_ID_MICROCHIP, USB_DEVICE_ID_PICDEM) }, 96 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_LCSPEC) }, 97 { } /* Terminating entry */ 98 }; 99 MODULE_DEVICE_TABLE(usb, ld_usb_table); 100 MODULE_VERSION("V0.13"); 101 MODULE_AUTHOR("Michael Hund <mhund@ld-didactic.de>"); 102 MODULE_DESCRIPTION("LD USB Driver"); 103 MODULE_LICENSE("GPL"); 104 MODULE_SUPPORTED_DEVICE("LD USB Devices"); 105 106 #ifdef CONFIG_USB_DEBUG 107 static int debug = 1; 108 #else 109 static int debug = 0; 110 #endif 111 112 /* Use our own dbg macro */ 113 #define dbg_info(dev, format, arg...) do { if (debug) dev_info(dev , format , ## arg); } while (0) 114 115 /* Module parameters */ 116 module_param(debug, int, S_IRUGO | S_IWUSR); 117 MODULE_PARM_DESC(debug, "Debug enabled or not"); 118 119 /* All interrupt in transfers are collected in a ring buffer to 120 * avoid racing conditions and get better performance of the driver. 121 */ 122 static int ring_buffer_size = 128; 123 module_param(ring_buffer_size, int, 0); 124 MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size in reports"); 125 126 /* The write_buffer can contain more than one interrupt out transfer. 127 */ 128 static int write_buffer_size = 10; 129 module_param(write_buffer_size, int, 0); 130 MODULE_PARM_DESC(write_buffer_size, "Write buffer size in reports"); 131 132 /* As of kernel version 2.6.4 ehci-hcd uses an 133 * "only one interrupt transfer per frame" shortcut 134 * to simplify the scheduling of periodic transfers. 135 * This conflicts with our standard 1ms intervals for in and out URBs. 136 * We use default intervals of 2ms for in and 2ms for out transfers, 137 * which should be fast enough. 138 * Increase the interval to allow more devices that do interrupt transfers, 139 * or set to 1 to use the standard interval from the endpoint descriptors. 140 */ 141 static int min_interrupt_in_interval = 2; 142 module_param(min_interrupt_in_interval, int, 0); 143 MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms"); 144 145 static int min_interrupt_out_interval = 2; 146 module_param(min_interrupt_out_interval, int, 0); 147 MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms"); 148 149 /* Structure to hold all of our device specific stuff */ 150 struct ld_usb { 151 struct mutex mutex; /* locks this structure */ 152 struct usb_interface* intf; /* save off the usb interface pointer */ 153 154 int open_count; /* number of times this port has been opened */ 155 156 char* ring_buffer; 157 unsigned int ring_head; 158 unsigned int ring_tail; 159 160 wait_queue_head_t read_wait; 161 wait_queue_head_t write_wait; 162 163 char* interrupt_in_buffer; 164 struct usb_endpoint_descriptor* interrupt_in_endpoint; 165 struct urb* interrupt_in_urb; 166 int interrupt_in_interval; 167 size_t interrupt_in_endpoint_size; 168 int interrupt_in_running; 169 int interrupt_in_done; 170 int buffer_overflow; 171 spinlock_t rbsl; 172 173 char* interrupt_out_buffer; 174 struct usb_endpoint_descriptor* interrupt_out_endpoint; 175 struct urb* interrupt_out_urb; 176 int interrupt_out_interval; 177 size_t interrupt_out_endpoint_size; 178 int interrupt_out_busy; 179 }; 180 181 static struct usb_driver ld_usb_driver; 182 183 /** 184 * ld_usb_abort_transfers 185 * aborts transfers and frees associated data structures 186 */ 187 static void ld_usb_abort_transfers(struct ld_usb *dev) 188 { 189 /* shutdown transfer */ 190 if (dev->interrupt_in_running) { 191 dev->interrupt_in_running = 0; 192 if (dev->intf) 193 usb_kill_urb(dev->interrupt_in_urb); 194 } 195 if (dev->interrupt_out_busy) 196 if (dev->intf) 197 usb_kill_urb(dev->interrupt_out_urb); 198 } 199 200 /** 201 * ld_usb_delete 202 */ 203 static void ld_usb_delete(struct ld_usb *dev) 204 { 205 ld_usb_abort_transfers(dev); 206 207 /* free data structures */ 208 usb_free_urb(dev->interrupt_in_urb); 209 usb_free_urb(dev->interrupt_out_urb); 210 kfree(dev->ring_buffer); 211 kfree(dev->interrupt_in_buffer); 212 kfree(dev->interrupt_out_buffer); 213 kfree(dev); 214 } 215 216 /** 217 * ld_usb_interrupt_in_callback 218 */ 219 static void ld_usb_interrupt_in_callback(struct urb *urb) 220 { 221 struct ld_usb *dev = urb->context; 222 size_t *actual_buffer; 223 unsigned int next_ring_head; 224 int status = urb->status; 225 int retval; 226 227 if (status) { 228 if (status == -ENOENT || 229 status == -ECONNRESET || 230 status == -ESHUTDOWN) { 231 goto exit; 232 } else { 233 dbg_info(&dev->intf->dev, "%s: nonzero status received: %d\n", 234 __func__, 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 __func__, 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 int status = urb->status; 282 283 /* sync/async unlink faults aren't errors */ 284 if (status && !(status == -ENOENT || 285 status == -ECONNRESET || 286 status == -ESHUTDOWN)) 287 dbg_info(&dev->intf->dev, 288 "%s - nonzero write interrupt status received: %d\n", 289 __func__, status); 290 291 dev->interrupt_out_busy = 0; 292 wake_up_interruptible(&dev->write_wait); 293 } 294 295 /** 296 * ld_usb_open 297 */ 298 static int ld_usb_open(struct inode *inode, struct file *file) 299 { 300 struct ld_usb *dev; 301 int subminor; 302 int retval; 303 struct usb_interface *interface; 304 305 nonseekable_open(inode, file); 306 subminor = iminor(inode); 307 308 interface = usb_find_interface(&ld_usb_driver, subminor); 309 310 if (!interface) { 311 err("%s - error, can't find device for minor %d\n", 312 __func__, subminor); 313 return -ENODEV; 314 } 315 316 dev = usb_get_intfdata(interface); 317 318 if (!dev) 319 return -ENODEV; 320 321 /* lock this device */ 322 if (mutex_lock_interruptible(&dev->mutex)) 323 return -ERESTARTSYS; 324 325 /* allow opening only once */ 326 if (dev->open_count) { 327 retval = -EBUSY; 328 goto unlock_exit; 329 } 330 dev->open_count = 1; 331 332 /* initialize in direction */ 333 dev->ring_head = 0; 334 dev->ring_tail = 0; 335 dev->buffer_overflow = 0; 336 usb_fill_int_urb(dev->interrupt_in_urb, 337 interface_to_usbdev(interface), 338 usb_rcvintpipe(interface_to_usbdev(interface), 339 dev->interrupt_in_endpoint->bEndpointAddress), 340 dev->interrupt_in_buffer, 341 dev->interrupt_in_endpoint_size, 342 ld_usb_interrupt_in_callback, 343 dev, 344 dev->interrupt_in_interval); 345 346 dev->interrupt_in_running = 1; 347 dev->interrupt_in_done = 0; 348 349 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 350 if (retval) { 351 dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval); 352 dev->interrupt_in_running = 0; 353 dev->open_count = 0; 354 goto unlock_exit; 355 } 356 357 /* save device in the file's private structure */ 358 file->private_data = dev; 359 360 unlock_exit: 361 mutex_unlock(&dev->mutex); 362 363 return retval; 364 } 365 366 /** 367 * ld_usb_release 368 */ 369 static int ld_usb_release(struct inode *inode, struct file *file) 370 { 371 struct ld_usb *dev; 372 int retval = 0; 373 374 dev = file->private_data; 375 376 if (dev == NULL) { 377 retval = -ENODEV; 378 goto exit; 379 } 380 381 if (mutex_lock_interruptible(&dev->mutex)) { 382 retval = -ERESTARTSYS; 383 goto exit; 384 } 385 386 if (dev->open_count != 1) { 387 retval = -ENODEV; 388 goto unlock_exit; 389 } 390 if (dev->intf == NULL) { 391 /* the device was unplugged before the file was released */ 392 mutex_unlock(&dev->mutex); 393 /* unlock here as ld_usb_delete frees dev */ 394 ld_usb_delete(dev); 395 goto exit; 396 } 397 398 /* wait until write transfer is finished */ 399 if (dev->interrupt_out_busy) 400 wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ); 401 ld_usb_abort_transfers(dev); 402 dev->open_count = 0; 403 404 unlock_exit: 405 mutex_unlock(&dev->mutex); 406 407 exit: 408 return retval; 409 } 410 411 /** 412 * ld_usb_poll 413 */ 414 static unsigned int ld_usb_poll(struct file *file, poll_table *wait) 415 { 416 struct ld_usb *dev; 417 unsigned int mask = 0; 418 419 dev = file->private_data; 420 421 poll_wait(file, &dev->read_wait, wait); 422 poll_wait(file, &dev->write_wait, wait); 423 424 if (dev->ring_head != dev->ring_tail) 425 mask |= POLLIN | POLLRDNORM; 426 if (!dev->interrupt_out_busy) 427 mask |= POLLOUT | POLLWRNORM; 428 429 return mask; 430 } 431 432 /** 433 * ld_usb_read 434 */ 435 static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count, 436 loff_t *ppos) 437 { 438 struct ld_usb *dev; 439 size_t *actual_buffer; 440 size_t bytes_to_read; 441 int retval = 0; 442 int rv; 443 444 dev = file->private_data; 445 446 /* verify that we actually have some data to read */ 447 if (count == 0) 448 goto exit; 449 450 /* lock this object */ 451 if (mutex_lock_interruptible(&dev->mutex)) { 452 retval = -ERESTARTSYS; 453 goto exit; 454 } 455 456 /* verify that the device wasn't unplugged */ 457 if (dev->intf == NULL) { 458 retval = -ENODEV; 459 err("No device or device unplugged %d\n", retval); 460 goto unlock_exit; 461 } 462 463 /* wait for data */ 464 spin_lock_irq(&dev->rbsl); 465 if (dev->ring_head == dev->ring_tail) { 466 dev->interrupt_in_done = 0; 467 spin_unlock_irq(&dev->rbsl); 468 if (file->f_flags & O_NONBLOCK) { 469 retval = -EAGAIN; 470 goto unlock_exit; 471 } 472 retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done); 473 if (retval < 0) 474 goto unlock_exit; 475 } else { 476 spin_unlock_irq(&dev->rbsl); 477 } 478 479 /* actual_buffer contains actual_length + interrupt_in_buffer */ 480 actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_tail*(sizeof(size_t)+dev->interrupt_in_endpoint_size)); 481 bytes_to_read = min(count, *actual_buffer); 482 if (bytes_to_read < *actual_buffer) 483 dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n", 484 *actual_buffer-bytes_to_read); 485 486 /* copy one interrupt_in_buffer from ring_buffer into userspace */ 487 if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) { 488 retval = -EFAULT; 489 goto unlock_exit; 490 } 491 dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size; 492 493 retval = bytes_to_read; 494 495 spin_lock_irq(&dev->rbsl); 496 if (dev->buffer_overflow) { 497 dev->buffer_overflow = 0; 498 spin_unlock_irq(&dev->rbsl); 499 rv = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 500 if (rv < 0) 501 dev->buffer_overflow = 1; 502 } else { 503 spin_unlock_irq(&dev->rbsl); 504 } 505 506 unlock_exit: 507 /* unlock the device */ 508 mutex_unlock(&dev->mutex); 509 510 exit: 511 return retval; 512 } 513 514 /** 515 * ld_usb_write 516 */ 517 static ssize_t ld_usb_write(struct file *file, const char __user *buffer, 518 size_t count, loff_t *ppos) 519 { 520 struct ld_usb *dev; 521 size_t bytes_to_write; 522 int retval = 0; 523 524 dev = file->private_data; 525 526 /* verify that we actually have some data to write */ 527 if (count == 0) 528 goto exit; 529 530 /* lock this object */ 531 if (mutex_lock_interruptible(&dev->mutex)) { 532 retval = -ERESTARTSYS; 533 goto exit; 534 } 535 536 /* verify that the device wasn't unplugged */ 537 if (dev->intf == NULL) { 538 retval = -ENODEV; 539 err("No device or device unplugged %d\n", retval); 540 goto unlock_exit; 541 } 542 543 /* wait until previous transfer is finished */ 544 if (dev->interrupt_out_busy) { 545 if (file->f_flags & O_NONBLOCK) { 546 retval = -EAGAIN; 547 goto unlock_exit; 548 } 549 retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy); 550 if (retval < 0) { 551 goto unlock_exit; 552 } 553 } 554 555 /* write the data into interrupt_out_buffer from userspace */ 556 bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size); 557 if (bytes_to_write < count) 558 dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n",count-bytes_to_write); 559 dbg_info(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n", __func__, count, bytes_to_write); 560 561 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) { 562 retval = -EFAULT; 563 goto unlock_exit; 564 } 565 566 if (dev->interrupt_out_endpoint == NULL) { 567 /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */ 568 retval = usb_control_msg(interface_to_usbdev(dev->intf), 569 usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0), 570 9, 571 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT, 572 1 << 8, 0, 573 dev->interrupt_out_buffer, 574 bytes_to_write, 575 USB_CTRL_SET_TIMEOUT * HZ); 576 if (retval < 0) 577 err("Couldn't submit HID_REQ_SET_REPORT %d\n", retval); 578 goto unlock_exit; 579 } 580 581 /* send off the urb */ 582 usb_fill_int_urb(dev->interrupt_out_urb, 583 interface_to_usbdev(dev->intf), 584 usb_sndintpipe(interface_to_usbdev(dev->intf), 585 dev->interrupt_out_endpoint->bEndpointAddress), 586 dev->interrupt_out_buffer, 587 bytes_to_write, 588 ld_usb_interrupt_out_callback, 589 dev, 590 dev->interrupt_out_interval); 591 592 dev->interrupt_out_busy = 1; 593 wmb(); 594 595 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL); 596 if (retval) { 597 dev->interrupt_out_busy = 0; 598 err("Couldn't submit interrupt_out_urb %d\n", retval); 599 goto unlock_exit; 600 } 601 retval = bytes_to_write; 602 603 unlock_exit: 604 /* unlock the device */ 605 mutex_unlock(&dev->mutex); 606 607 exit: 608 return retval; 609 } 610 611 /* file operations needed when we register this driver */ 612 static const struct file_operations ld_usb_fops = { 613 .owner = THIS_MODULE, 614 .read = ld_usb_read, 615 .write = ld_usb_write, 616 .open = ld_usb_open, 617 .release = ld_usb_release, 618 .poll = ld_usb_poll, 619 }; 620 621 /* 622 * usb class driver info in order to get a minor number from the usb core, 623 * and to have the device registered with the driver core 624 */ 625 static struct usb_class_driver ld_usb_class = { 626 .name = "ldusb%d", 627 .fops = &ld_usb_fops, 628 .minor_base = USB_LD_MINOR_BASE, 629 }; 630 631 /** 632 * ld_usb_probe 633 * 634 * Called by the usb core when a new device is connected that it thinks 635 * this driver might be interested in. 636 */ 637 static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id) 638 { 639 struct usb_device *udev = interface_to_usbdev(intf); 640 struct ld_usb *dev = NULL; 641 struct usb_host_interface *iface_desc; 642 struct usb_endpoint_descriptor *endpoint; 643 char *buffer; 644 int i; 645 int retval = -ENOMEM; 646 647 /* allocate memory for our device state and intialize it */ 648 649 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 650 if (dev == NULL) { 651 dev_err(&intf->dev, "Out of memory\n"); 652 goto exit; 653 } 654 mutex_init(&dev->mutex); 655 spin_lock_init(&dev->rbsl); 656 dev->intf = intf; 657 init_waitqueue_head(&dev->read_wait); 658 init_waitqueue_head(&dev->write_wait); 659 660 /* workaround for early firmware versions on fast computers */ 661 if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) && 662 ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) || 663 (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) && 664 (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) { 665 buffer = kmalloc(256, GFP_KERNEL); 666 if (buffer == NULL) { 667 dev_err(&intf->dev, "Couldn't allocate string buffer\n"); 668 goto error; 669 } 670 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */ 671 usb_string(udev, 255, buffer, 256); 672 kfree(buffer); 673 } 674 675 iface_desc = intf->cur_altsetting; 676 677 /* set up the endpoint information */ 678 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) { 679 endpoint = &iface_desc->endpoint[i].desc; 680 681 if (usb_endpoint_is_int_in(endpoint)) 682 dev->interrupt_in_endpoint = endpoint; 683 684 if (usb_endpoint_is_int_out(endpoint)) 685 dev->interrupt_out_endpoint = endpoint; 686 } 687 if (dev->interrupt_in_endpoint == NULL) { 688 dev_err(&intf->dev, "Interrupt in endpoint not found\n"); 689 goto error; 690 } 691 if (dev->interrupt_out_endpoint == NULL) 692 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n"); 693 694 dev->interrupt_in_endpoint_size = le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize); 695 dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL); 696 if (!dev->ring_buffer) { 697 dev_err(&intf->dev, "Couldn't allocate ring_buffer\n"); 698 goto error; 699 } 700 dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL); 701 if (!dev->interrupt_in_buffer) { 702 dev_err(&intf->dev, "Couldn't allocate interrupt_in_buffer\n"); 703 goto error; 704 } 705 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL); 706 if (!dev->interrupt_in_urb) { 707 dev_err(&intf->dev, "Couldn't allocate interrupt_in_urb\n"); 708 goto error; 709 } 710 dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? le16_to_cpu(dev->interrupt_out_endpoint->wMaxPacketSize) : 711 udev->descriptor.bMaxPacketSize0; 712 dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL); 713 if (!dev->interrupt_out_buffer) { 714 dev_err(&intf->dev, "Couldn't allocate interrupt_out_buffer\n"); 715 goto error; 716 } 717 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL); 718 if (!dev->interrupt_out_urb) { 719 dev_err(&intf->dev, "Couldn't allocate interrupt_out_urb\n"); 720 goto error; 721 } 722 dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval; 723 if (dev->interrupt_out_endpoint) 724 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval; 725 726 /* we can register the device now, as it is ready */ 727 usb_set_intfdata(intf, dev); 728 729 retval = usb_register_dev(intf, &ld_usb_class); 730 if (retval) { 731 /* something prevented us from registering this driver */ 732 dev_err(&intf->dev, "Not able to get a minor for this device.\n"); 733 usb_set_intfdata(intf, NULL); 734 goto error; 735 } 736 737 /* let the user know what node this device is now attached to */ 738 dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n", 739 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor); 740 741 exit: 742 return retval; 743 744 error: 745 ld_usb_delete(dev); 746 747 return retval; 748 } 749 750 /** 751 * ld_usb_disconnect 752 * 753 * Called by the usb core when the device is removed from the system. 754 */ 755 static void ld_usb_disconnect(struct usb_interface *intf) 756 { 757 struct ld_usb *dev; 758 int minor; 759 760 dev = usb_get_intfdata(intf); 761 usb_set_intfdata(intf, NULL); 762 763 minor = intf->minor; 764 765 /* give back our minor */ 766 usb_deregister_dev(intf, &ld_usb_class); 767 768 mutex_lock(&dev->mutex); 769 770 /* if the device is not opened, then we clean up right now */ 771 if (!dev->open_count) { 772 mutex_unlock(&dev->mutex); 773 ld_usb_delete(dev); 774 } else { 775 dev->intf = NULL; 776 mutex_unlock(&dev->mutex); 777 } 778 779 dev_info(&intf->dev, "LD USB Device #%d now disconnected\n", 780 (minor - USB_LD_MINOR_BASE)); 781 } 782 783 /* usb specific object needed to register this driver with the usb subsystem */ 784 static struct usb_driver ld_usb_driver = { 785 .name = "ldusb", 786 .probe = ld_usb_probe, 787 .disconnect = ld_usb_disconnect, 788 .id_table = ld_usb_table, 789 }; 790 791 /** 792 * ld_usb_init 793 */ 794 static int __init ld_usb_init(void) 795 { 796 int retval; 797 798 /* register this driver with the USB subsystem */ 799 retval = usb_register(&ld_usb_driver); 800 if (retval) 801 err("usb_register failed for the "__FILE__" driver. Error number %d\n", retval); 802 803 return retval; 804 } 805 806 /** 807 * ld_usb_exit 808 */ 809 static void __exit ld_usb_exit(void) 810 { 811 /* deregister this driver with the USB subsystem */ 812 usb_deregister(&ld_usb_driver); 813 } 814 815 module_init(ld_usb_init); 816 module_exit(ld_usb_exit); 817 818