1 /** 2 * Generic USB driver for report based interrupt in/out devices 3 * like LD Didactic's USB devices. LD Didactic's USB devices are 4 * HID devices which do not use HID report definitons (they use 5 * raw interrupt in and our reports only for communication). 6 * 7 * This driver uses a ring buffer for time critical reading of 8 * interrupt in reports and provides read and write methods for 9 * raw interrupt reports (similar to the Windows HID driver). 10 * Devices based on the book USB COMPLETE by Jan Axelson may need 11 * such a compatibility to the Windows HID driver. 12 * 13 * Copyright (C) 2005 Michael Hund <mhund@ld-didactic.de> 14 * 15 * This program is free software; you can redistribute it and/or 16 * modify it under the terms of the GNU General Public License as 17 * published by the Free Software Foundation; either version 2 of 18 * the License, or (at your option) any later version. 19 * 20 * Derived from Lego USB Tower driver 21 * Copyright (C) 2003 David Glance <advidgsf@sourceforge.net> 22 * 2001-2004 Juergen Stuber <starblue@users.sourceforge.net> 23 * 24 * V0.1 (mh) Initial version 25 * V0.11 (mh) Added raw support for HID 1.0 devices (no interrupt out endpoint) 26 * V0.12 (mh) Added kmalloc check for string buffer 27 * V0.13 (mh) Added support for LD X-Ray and Machine Test System 28 */ 29 30 #include <linux/kernel.h> 31 #include <linux/errno.h> 32 #include <linux/init.h> 33 #include <linux/slab.h> 34 #include <linux/module.h> 35 #include <linux/mutex.h> 36 37 #include <asm/uaccess.h> 38 #include <linux/input.h> 39 #include <linux/usb.h> 40 #include <linux/poll.h> 41 42 /* Define these values to match your devices */ 43 #define USB_VENDOR_ID_LD 0x0f11 /* USB Vendor ID of LD Didactic GmbH */ 44 #define USB_DEVICE_ID_LD_CASSY 0x1000 /* USB Product ID of CASSY-S */ 45 #define USB_DEVICE_ID_LD_POCKETCASSY 0x1010 /* USB Product ID of Pocket-CASSY */ 46 #define USB_DEVICE_ID_LD_MOBILECASSY 0x1020 /* USB Product ID of Mobile-CASSY */ 47 #define USB_DEVICE_ID_LD_JWM 0x1080 /* USB Product ID of Joule and Wattmeter */ 48 #define USB_DEVICE_ID_LD_DMMP 0x1081 /* USB Product ID of Digital Multimeter P (reserved) */ 49 #define USB_DEVICE_ID_LD_UMIP 0x1090 /* USB Product ID of UMI P */ 50 #define USB_DEVICE_ID_LD_XRAY1 0x1100 /* USB Product ID of X-Ray Apparatus */ 51 #define USB_DEVICE_ID_LD_XRAY2 0x1101 /* USB Product ID of X-Ray Apparatus */ 52 #define USB_DEVICE_ID_LD_VIDEOCOM 0x1200 /* USB Product ID of VideoCom */ 53 #define USB_DEVICE_ID_LD_COM3LAB 0x2000 /* USB Product ID of COM3LAB */ 54 #define USB_DEVICE_ID_LD_TELEPORT 0x2010 /* USB Product ID of Terminal Adapter */ 55 #define USB_DEVICE_ID_LD_NETWORKANALYSER 0x2020 /* USB Product ID of Network Analyser */ 56 #define USB_DEVICE_ID_LD_POWERCONTROL 0x2030 /* USB Product ID of Converter Control Unit */ 57 #define USB_DEVICE_ID_LD_MACHINETEST 0x2040 /* USB Product ID of Machine Test System */ 58 59 #define USB_VENDOR_ID_VERNIER 0x08f7 60 #define USB_DEVICE_ID_VERNIER_LABPRO 0x0001 61 #define USB_DEVICE_ID_VERNIER_GOTEMP 0x0002 62 #define USB_DEVICE_ID_VERNIER_SKIP 0x0003 63 #define USB_DEVICE_ID_VERNIER_CYCLOPS 0x0004 64 65 #define USB_VENDOR_ID_MICROCHIP 0x04d8 66 #define USB_DEVICE_ID_PICDEM 0x000c 67 68 #ifdef CONFIG_USB_DYNAMIC_MINORS 69 #define USB_LD_MINOR_BASE 0 70 #else 71 #define USB_LD_MINOR_BASE 176 72 #endif 73 74 /* table of devices that work with this driver */ 75 static struct usb_device_id ld_usb_table [] = { 76 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_CASSY) }, 77 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POCKETCASSY) }, 78 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MOBILECASSY) }, 79 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_JWM) }, 80 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_DMMP) }, 81 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_UMIP) }, 82 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY1) }, 83 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_XRAY2) }, 84 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_VIDEOCOM) }, 85 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_COM3LAB) }, 86 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_TELEPORT) }, 87 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_NETWORKANALYSER) }, 88 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_POWERCONTROL) }, 89 { USB_DEVICE(USB_VENDOR_ID_LD, USB_DEVICE_ID_LD_MACHINETEST) }, 90 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_LABPRO) }, 91 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_GOTEMP) }, 92 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_SKIP) }, 93 { USB_DEVICE(USB_VENDOR_ID_VERNIER, USB_DEVICE_ID_VERNIER_CYCLOPS) }, 94 { USB_DEVICE(USB_VENDOR_ID_MICROCHIP, USB_DEVICE_ID_PICDEM) }, 95 { } /* Terminating entry */ 96 }; 97 MODULE_DEVICE_TABLE(usb, ld_usb_table); 98 MODULE_VERSION("V0.13"); 99 MODULE_AUTHOR("Michael Hund <mhund@ld-didactic.de>"); 100 MODULE_DESCRIPTION("LD USB Driver"); 101 MODULE_LICENSE("GPL"); 102 MODULE_SUPPORTED_DEVICE("LD USB Devices"); 103 104 #ifdef CONFIG_USB_DEBUG 105 static int debug = 1; 106 #else 107 static int debug = 0; 108 #endif 109 110 /* Use our own dbg macro */ 111 #define dbg_info(dev, format, arg...) do { if (debug) dev_info(dev , format , ## arg); } while (0) 112 113 /* Module parameters */ 114 module_param(debug, int, S_IRUGO | S_IWUSR); 115 MODULE_PARM_DESC(debug, "Debug enabled or not"); 116 117 /* All interrupt in transfers are collected in a ring buffer to 118 * avoid racing conditions and get better performance of the driver. 119 */ 120 static int ring_buffer_size = 128; 121 module_param(ring_buffer_size, int, 0); 122 MODULE_PARM_DESC(ring_buffer_size, "Read ring buffer size in reports"); 123 124 /* The write_buffer can contain more than one interrupt out transfer. 125 */ 126 static int write_buffer_size = 10; 127 module_param(write_buffer_size, int, 0); 128 MODULE_PARM_DESC(write_buffer_size, "Write buffer size in reports"); 129 130 /* As of kernel version 2.6.4 ehci-hcd uses an 131 * "only one interrupt transfer per frame" shortcut 132 * to simplify the scheduling of periodic transfers. 133 * This conflicts with our standard 1ms intervals for in and out URBs. 134 * We use default intervals of 2ms for in and 2ms for out transfers, 135 * which should be fast enough. 136 * Increase the interval to allow more devices that do interrupt transfers, 137 * or set to 1 to use the standard interval from the endpoint descriptors. 138 */ 139 static int min_interrupt_in_interval = 2; 140 module_param(min_interrupt_in_interval, int, 0); 141 MODULE_PARM_DESC(min_interrupt_in_interval, "Minimum interrupt in interval in ms"); 142 143 static int min_interrupt_out_interval = 2; 144 module_param(min_interrupt_out_interval, int, 0); 145 MODULE_PARM_DESC(min_interrupt_out_interval, "Minimum interrupt out interval in ms"); 146 147 /* Structure to hold all of our device specific stuff */ 148 struct ld_usb { 149 struct semaphore sem; /* locks this structure */ 150 struct usb_interface* intf; /* save off the usb interface pointer */ 151 152 int open_count; /* number of times this port has been opened */ 153 154 char* ring_buffer; 155 unsigned int ring_head; 156 unsigned int ring_tail; 157 158 wait_queue_head_t read_wait; 159 wait_queue_head_t write_wait; 160 161 char* interrupt_in_buffer; 162 struct usb_endpoint_descriptor* interrupt_in_endpoint; 163 struct urb* interrupt_in_urb; 164 int interrupt_in_interval; 165 size_t interrupt_in_endpoint_size; 166 int interrupt_in_running; 167 int interrupt_in_done; 168 int buffer_overflow; 169 spinlock_t rbsl; 170 171 char* interrupt_out_buffer; 172 struct usb_endpoint_descriptor* interrupt_out_endpoint; 173 struct urb* interrupt_out_urb; 174 int interrupt_out_interval; 175 size_t interrupt_out_endpoint_size; 176 int interrupt_out_busy; 177 }; 178 179 static struct usb_driver ld_usb_driver; 180 181 /** 182 * ld_usb_abort_transfers 183 * aborts transfers and frees associated data structures 184 */ 185 static void ld_usb_abort_transfers(struct ld_usb *dev) 186 { 187 /* shutdown transfer */ 188 if (dev->interrupt_in_running) { 189 dev->interrupt_in_running = 0; 190 if (dev->intf) 191 usb_kill_urb(dev->interrupt_in_urb); 192 } 193 if (dev->interrupt_out_busy) 194 if (dev->intf) 195 usb_kill_urb(dev->interrupt_out_urb); 196 } 197 198 /** 199 * ld_usb_delete 200 */ 201 static void ld_usb_delete(struct ld_usb *dev) 202 { 203 ld_usb_abort_transfers(dev); 204 205 /* free data structures */ 206 usb_free_urb(dev->interrupt_in_urb); 207 usb_free_urb(dev->interrupt_out_urb); 208 kfree(dev->ring_buffer); 209 kfree(dev->interrupt_in_buffer); 210 kfree(dev->interrupt_out_buffer); 211 kfree(dev); 212 } 213 214 /** 215 * ld_usb_interrupt_in_callback 216 */ 217 static void ld_usb_interrupt_in_callback(struct urb *urb) 218 { 219 struct ld_usb *dev = urb->context; 220 size_t *actual_buffer; 221 unsigned int next_ring_head; 222 int retval; 223 224 if (urb->status) { 225 if (urb->status == -ENOENT || 226 urb->status == -ECONNRESET || 227 urb->status == -ESHUTDOWN) { 228 goto exit; 229 } else { 230 dbg_info(&dev->intf->dev, "%s: nonzero status received: %d\n", 231 __FUNCTION__, urb->status); 232 spin_lock(&dev->rbsl); 233 goto resubmit; /* maybe we can recover */ 234 } 235 } 236 237 spin_lock(&dev->rbsl); 238 if (urb->actual_length > 0) { 239 next_ring_head = (dev->ring_head+1) % ring_buffer_size; 240 if (next_ring_head != dev->ring_tail) { 241 actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_head*(sizeof(size_t)+dev->interrupt_in_endpoint_size)); 242 /* actual_buffer gets urb->actual_length + interrupt_in_buffer */ 243 *actual_buffer = urb->actual_length; 244 memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length); 245 dev->ring_head = next_ring_head; 246 dbg_info(&dev->intf->dev, "%s: received %d bytes\n", 247 __FUNCTION__, urb->actual_length); 248 } else { 249 dev_warn(&dev->intf->dev, 250 "Ring buffer overflow, %d bytes dropped\n", 251 urb->actual_length); 252 dev->buffer_overflow = 1; 253 } 254 } 255 256 resubmit: 257 /* resubmit if we're still running */ 258 if (dev->interrupt_in_running && !dev->buffer_overflow && dev->intf) { 259 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC); 260 if (retval) { 261 dev_err(&dev->intf->dev, 262 "usb_submit_urb failed (%d)\n", retval); 263 dev->buffer_overflow = 1; 264 } 265 } 266 spin_unlock(&dev->rbsl); 267 exit: 268 dev->interrupt_in_done = 1; 269 wake_up_interruptible(&dev->read_wait); 270 } 271 272 /** 273 * ld_usb_interrupt_out_callback 274 */ 275 static void ld_usb_interrupt_out_callback(struct urb *urb) 276 { 277 struct ld_usb *dev = urb->context; 278 279 /* sync/async unlink faults aren't errors */ 280 if (urb->status && !(urb->status == -ENOENT || 281 urb->status == -ECONNRESET || 282 urb->status == -ESHUTDOWN)) 283 dbg_info(&dev->intf->dev, 284 "%s - nonzero write interrupt status received: %d\n", 285 __FUNCTION__, urb->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 __FUNCTION__, 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 (down_interruptible(&dev->sem)) 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 up(&dev->sem); 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 (down_interruptible(&dev->sem)) { 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 up(&dev->sem); 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 up(&dev->sem); 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 (down_interruptible(&dev->sem)) { 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 up(&dev->sem); 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 (down_interruptible(&dev->sem)) { 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", __FUNCTION__, 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 up(&dev->sem); 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 init_MUTEX(&dev->sem); 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 down(&dev->sem); 765 766 /* if the device is not opened, then we clean up right now */ 767 if (!dev->open_count) { 768 up(&dev->sem); 769 ld_usb_delete(dev); 770 } else { 771 dev->intf = NULL; 772 up(&dev->sem); 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); 813 814