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 status = urb->status; 223 int retval; 224 225 if (status) { 226 if (status == -ENOENT || 227 status == -ECONNRESET || 228 status == -ESHUTDOWN) { 229 goto exit; 230 } else { 231 dbg_info(&dev->intf->dev, "%s: nonzero status received: %d\n", 232 __FUNCTION__, status); 233 spin_lock(&dev->rbsl); 234 goto resubmit; /* maybe we can recover */ 235 } 236 } 237 238 spin_lock(&dev->rbsl); 239 if (urb->actual_length > 0) { 240 next_ring_head = (dev->ring_head+1) % ring_buffer_size; 241 if (next_ring_head != dev->ring_tail) { 242 actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_head*(sizeof(size_t)+dev->interrupt_in_endpoint_size)); 243 /* actual_buffer gets urb->actual_length + interrupt_in_buffer */ 244 *actual_buffer = urb->actual_length; 245 memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length); 246 dev->ring_head = next_ring_head; 247 dbg_info(&dev->intf->dev, "%s: received %d bytes\n", 248 __FUNCTION__, urb->actual_length); 249 } else { 250 dev_warn(&dev->intf->dev, 251 "Ring buffer overflow, %d bytes dropped\n", 252 urb->actual_length); 253 dev->buffer_overflow = 1; 254 } 255 } 256 257 resubmit: 258 /* resubmit if we're still running */ 259 if (dev->interrupt_in_running && !dev->buffer_overflow && dev->intf) { 260 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC); 261 if (retval) { 262 dev_err(&dev->intf->dev, 263 "usb_submit_urb failed (%d)\n", retval); 264 dev->buffer_overflow = 1; 265 } 266 } 267 spin_unlock(&dev->rbsl); 268 exit: 269 dev->interrupt_in_done = 1; 270 wake_up_interruptible(&dev->read_wait); 271 } 272 273 /** 274 * ld_usb_interrupt_out_callback 275 */ 276 static void ld_usb_interrupt_out_callback(struct urb *urb) 277 { 278 struct ld_usb *dev = urb->context; 279 int status = urb->status; 280 281 /* sync/async unlink faults aren't errors */ 282 if (status && !(status == -ENOENT || 283 status == -ECONNRESET || 284 status == -ESHUTDOWN)) 285 dbg_info(&dev->intf->dev, 286 "%s - nonzero write interrupt status received: %d\n", 287 __FUNCTION__, status); 288 289 dev->interrupt_out_busy = 0; 290 wake_up_interruptible(&dev->write_wait); 291 } 292 293 /** 294 * ld_usb_open 295 */ 296 static int ld_usb_open(struct inode *inode, struct file *file) 297 { 298 struct ld_usb *dev; 299 int subminor; 300 int retval; 301 struct usb_interface *interface; 302 303 nonseekable_open(inode, file); 304 subminor = iminor(inode); 305 306 interface = usb_find_interface(&ld_usb_driver, subminor); 307 308 if (!interface) { 309 err("%s - error, can't find device for minor %d\n", 310 __FUNCTION__, subminor); 311 return -ENODEV; 312 } 313 314 dev = usb_get_intfdata(interface); 315 316 if (!dev) 317 return -ENODEV; 318 319 /* lock this device */ 320 if (down_interruptible(&dev->sem)) 321 return -ERESTARTSYS; 322 323 /* allow opening only once */ 324 if (dev->open_count) { 325 retval = -EBUSY; 326 goto unlock_exit; 327 } 328 dev->open_count = 1; 329 330 /* initialize in direction */ 331 dev->ring_head = 0; 332 dev->ring_tail = 0; 333 dev->buffer_overflow = 0; 334 usb_fill_int_urb(dev->interrupt_in_urb, 335 interface_to_usbdev(interface), 336 usb_rcvintpipe(interface_to_usbdev(interface), 337 dev->interrupt_in_endpoint->bEndpointAddress), 338 dev->interrupt_in_buffer, 339 dev->interrupt_in_endpoint_size, 340 ld_usb_interrupt_in_callback, 341 dev, 342 dev->interrupt_in_interval); 343 344 dev->interrupt_in_running = 1; 345 dev->interrupt_in_done = 0; 346 347 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 348 if (retval) { 349 dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval); 350 dev->interrupt_in_running = 0; 351 dev->open_count = 0; 352 goto unlock_exit; 353 } 354 355 /* save device in the file's private structure */ 356 file->private_data = dev; 357 358 unlock_exit: 359 up(&dev->sem); 360 361 return retval; 362 } 363 364 /** 365 * ld_usb_release 366 */ 367 static int ld_usb_release(struct inode *inode, struct file *file) 368 { 369 struct ld_usb *dev; 370 int retval = 0; 371 372 dev = file->private_data; 373 374 if (dev == NULL) { 375 retval = -ENODEV; 376 goto exit; 377 } 378 379 if (down_interruptible(&dev->sem)) { 380 retval = -ERESTARTSYS; 381 goto exit; 382 } 383 384 if (dev->open_count != 1) { 385 retval = -ENODEV; 386 goto unlock_exit; 387 } 388 if (dev->intf == NULL) { 389 /* the device was unplugged before the file was released */ 390 up(&dev->sem); 391 /* unlock here as ld_usb_delete frees dev */ 392 ld_usb_delete(dev); 393 goto exit; 394 } 395 396 /* wait until write transfer is finished */ 397 if (dev->interrupt_out_busy) 398 wait_event_interruptible_timeout(dev->write_wait, !dev->interrupt_out_busy, 2 * HZ); 399 ld_usb_abort_transfers(dev); 400 dev->open_count = 0; 401 402 unlock_exit: 403 up(&dev->sem); 404 405 exit: 406 return retval; 407 } 408 409 /** 410 * ld_usb_poll 411 */ 412 static unsigned int ld_usb_poll(struct file *file, poll_table *wait) 413 { 414 struct ld_usb *dev; 415 unsigned int mask = 0; 416 417 dev = file->private_data; 418 419 poll_wait(file, &dev->read_wait, wait); 420 poll_wait(file, &dev->write_wait, wait); 421 422 if (dev->ring_head != dev->ring_tail) 423 mask |= POLLIN | POLLRDNORM; 424 if (!dev->interrupt_out_busy) 425 mask |= POLLOUT | POLLWRNORM; 426 427 return mask; 428 } 429 430 /** 431 * ld_usb_read 432 */ 433 static ssize_t ld_usb_read(struct file *file, char __user *buffer, size_t count, 434 loff_t *ppos) 435 { 436 struct ld_usb *dev; 437 size_t *actual_buffer; 438 size_t bytes_to_read; 439 int retval = 0; 440 int rv; 441 442 dev = file->private_data; 443 444 /* verify that we actually have some data to read */ 445 if (count == 0) 446 goto exit; 447 448 /* lock this object */ 449 if (down_interruptible(&dev->sem)) { 450 retval = -ERESTARTSYS; 451 goto exit; 452 } 453 454 /* verify that the device wasn't unplugged */ 455 if (dev->intf == NULL) { 456 retval = -ENODEV; 457 err("No device or device unplugged %d\n", retval); 458 goto unlock_exit; 459 } 460 461 /* wait for data */ 462 spin_lock_irq(&dev->rbsl); 463 if (dev->ring_head == dev->ring_tail) { 464 dev->interrupt_in_done = 0; 465 spin_unlock_irq(&dev->rbsl); 466 if (file->f_flags & O_NONBLOCK) { 467 retval = -EAGAIN; 468 goto unlock_exit; 469 } 470 retval = wait_event_interruptible(dev->read_wait, dev->interrupt_in_done); 471 if (retval < 0) 472 goto unlock_exit; 473 } else { 474 spin_unlock_irq(&dev->rbsl); 475 } 476 477 /* actual_buffer contains actual_length + interrupt_in_buffer */ 478 actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_tail*(sizeof(size_t)+dev->interrupt_in_endpoint_size)); 479 bytes_to_read = min(count, *actual_buffer); 480 if (bytes_to_read < *actual_buffer) 481 dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n", 482 *actual_buffer-bytes_to_read); 483 484 /* copy one interrupt_in_buffer from ring_buffer into userspace */ 485 if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) { 486 retval = -EFAULT; 487 goto unlock_exit; 488 } 489 dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size; 490 491 retval = bytes_to_read; 492 493 spin_lock_irq(&dev->rbsl); 494 if (dev->buffer_overflow) { 495 dev->buffer_overflow = 0; 496 spin_unlock_irq(&dev->rbsl); 497 rv = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 498 if (rv < 0) 499 dev->buffer_overflow = 1; 500 } else { 501 spin_unlock_irq(&dev->rbsl); 502 } 503 504 unlock_exit: 505 /* unlock the device */ 506 up(&dev->sem); 507 508 exit: 509 return retval; 510 } 511 512 /** 513 * ld_usb_write 514 */ 515 static ssize_t ld_usb_write(struct file *file, const char __user *buffer, 516 size_t count, loff_t *ppos) 517 { 518 struct ld_usb *dev; 519 size_t bytes_to_write; 520 int retval = 0; 521 522 dev = file->private_data; 523 524 /* verify that we actually have some data to write */ 525 if (count == 0) 526 goto exit; 527 528 /* lock this object */ 529 if (down_interruptible(&dev->sem)) { 530 retval = -ERESTARTSYS; 531 goto exit; 532 } 533 534 /* verify that the device wasn't unplugged */ 535 if (dev->intf == NULL) { 536 retval = -ENODEV; 537 err("No device or device unplugged %d\n", retval); 538 goto unlock_exit; 539 } 540 541 /* wait until previous transfer is finished */ 542 if (dev->interrupt_out_busy) { 543 if (file->f_flags & O_NONBLOCK) { 544 retval = -EAGAIN; 545 goto unlock_exit; 546 } 547 retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy); 548 if (retval < 0) { 549 goto unlock_exit; 550 } 551 } 552 553 /* write the data into interrupt_out_buffer from userspace */ 554 bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size); 555 if (bytes_to_write < count) 556 dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n",count-bytes_to_write); 557 dbg_info(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n", __FUNCTION__, count, bytes_to_write); 558 559 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) { 560 retval = -EFAULT; 561 goto unlock_exit; 562 } 563 564 if (dev->interrupt_out_endpoint == NULL) { 565 /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */ 566 retval = usb_control_msg(interface_to_usbdev(dev->intf), 567 usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0), 568 9, 569 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT, 570 1 << 8, 0, 571 dev->interrupt_out_buffer, 572 bytes_to_write, 573 USB_CTRL_SET_TIMEOUT * HZ); 574 if (retval < 0) 575 err("Couldn't submit HID_REQ_SET_REPORT %d\n", retval); 576 goto unlock_exit; 577 } 578 579 /* send off the urb */ 580 usb_fill_int_urb(dev->interrupt_out_urb, 581 interface_to_usbdev(dev->intf), 582 usb_sndintpipe(interface_to_usbdev(dev->intf), 583 dev->interrupt_out_endpoint->bEndpointAddress), 584 dev->interrupt_out_buffer, 585 bytes_to_write, 586 ld_usb_interrupt_out_callback, 587 dev, 588 dev->interrupt_out_interval); 589 590 dev->interrupt_out_busy = 1; 591 wmb(); 592 593 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL); 594 if (retval) { 595 dev->interrupt_out_busy = 0; 596 err("Couldn't submit interrupt_out_urb %d\n", retval); 597 goto unlock_exit; 598 } 599 retval = bytes_to_write; 600 601 unlock_exit: 602 /* unlock the device */ 603 up(&dev->sem); 604 605 exit: 606 return retval; 607 } 608 609 /* file operations needed when we register this driver */ 610 static const struct file_operations ld_usb_fops = { 611 .owner = THIS_MODULE, 612 .read = ld_usb_read, 613 .write = ld_usb_write, 614 .open = ld_usb_open, 615 .release = ld_usb_release, 616 .poll = ld_usb_poll, 617 }; 618 619 /* 620 * usb class driver info in order to get a minor number from the usb core, 621 * and to have the device registered with the driver core 622 */ 623 static struct usb_class_driver ld_usb_class = { 624 .name = "ldusb%d", 625 .fops = &ld_usb_fops, 626 .minor_base = USB_LD_MINOR_BASE, 627 }; 628 629 /** 630 * ld_usb_probe 631 * 632 * Called by the usb core when a new device is connected that it thinks 633 * this driver might be interested in. 634 */ 635 static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id) 636 { 637 struct usb_device *udev = interface_to_usbdev(intf); 638 struct ld_usb *dev = NULL; 639 struct usb_host_interface *iface_desc; 640 struct usb_endpoint_descriptor *endpoint; 641 char *buffer; 642 int i; 643 int retval = -ENOMEM; 644 645 /* allocate memory for our device state and intialize it */ 646 647 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 648 if (dev == NULL) { 649 dev_err(&intf->dev, "Out of memory\n"); 650 goto exit; 651 } 652 init_MUTEX(&dev->sem); 653 spin_lock_init(&dev->rbsl); 654 dev->intf = intf; 655 init_waitqueue_head(&dev->read_wait); 656 init_waitqueue_head(&dev->write_wait); 657 658 /* workaround for early firmware versions on fast computers */ 659 if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) && 660 ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) || 661 (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) && 662 (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) { 663 buffer = kmalloc(256, GFP_KERNEL); 664 if (buffer == NULL) { 665 dev_err(&intf->dev, "Couldn't allocate string buffer\n"); 666 goto error; 667 } 668 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */ 669 usb_string(udev, 255, buffer, 256); 670 kfree(buffer); 671 } 672 673 iface_desc = intf->cur_altsetting; 674 675 /* set up the endpoint information */ 676 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) { 677 endpoint = &iface_desc->endpoint[i].desc; 678 679 if (usb_endpoint_is_int_in(endpoint)) 680 dev->interrupt_in_endpoint = endpoint; 681 682 if (usb_endpoint_is_int_out(endpoint)) 683 dev->interrupt_out_endpoint = endpoint; 684 } 685 if (dev->interrupt_in_endpoint == NULL) { 686 dev_err(&intf->dev, "Interrupt in endpoint not found\n"); 687 goto error; 688 } 689 if (dev->interrupt_out_endpoint == NULL) 690 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n"); 691 692 dev->interrupt_in_endpoint_size = le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize); 693 dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL); 694 if (!dev->ring_buffer) { 695 dev_err(&intf->dev, "Couldn't allocate ring_buffer\n"); 696 goto error; 697 } 698 dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL); 699 if (!dev->interrupt_in_buffer) { 700 dev_err(&intf->dev, "Couldn't allocate interrupt_in_buffer\n"); 701 goto error; 702 } 703 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL); 704 if (!dev->interrupt_in_urb) { 705 dev_err(&intf->dev, "Couldn't allocate interrupt_in_urb\n"); 706 goto error; 707 } 708 dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? le16_to_cpu(dev->interrupt_out_endpoint->wMaxPacketSize) : 709 udev->descriptor.bMaxPacketSize0; 710 dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL); 711 if (!dev->interrupt_out_buffer) { 712 dev_err(&intf->dev, "Couldn't allocate interrupt_out_buffer\n"); 713 goto error; 714 } 715 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL); 716 if (!dev->interrupt_out_urb) { 717 dev_err(&intf->dev, "Couldn't allocate interrupt_out_urb\n"); 718 goto error; 719 } 720 dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval; 721 if (dev->interrupt_out_endpoint) 722 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval; 723 724 /* we can register the device now, as it is ready */ 725 usb_set_intfdata(intf, dev); 726 727 retval = usb_register_dev(intf, &ld_usb_class); 728 if (retval) { 729 /* something prevented us from registering this driver */ 730 dev_err(&intf->dev, "Not able to get a minor for this device.\n"); 731 usb_set_intfdata(intf, NULL); 732 goto error; 733 } 734 735 /* let the user know what node this device is now attached to */ 736 dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n", 737 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor); 738 739 exit: 740 return retval; 741 742 error: 743 ld_usb_delete(dev); 744 745 return retval; 746 } 747 748 /** 749 * ld_usb_disconnect 750 * 751 * Called by the usb core when the device is removed from the system. 752 */ 753 static void ld_usb_disconnect(struct usb_interface *intf) 754 { 755 struct ld_usb *dev; 756 int minor; 757 758 dev = usb_get_intfdata(intf); 759 usb_set_intfdata(intf, NULL); 760 761 minor = intf->minor; 762 763 /* give back our minor */ 764 usb_deregister_dev(intf, &ld_usb_class); 765 766 down(&dev->sem); 767 768 /* if the device is not opened, then we clean up right now */ 769 if (!dev->open_count) { 770 up(&dev->sem); 771 ld_usb_delete(dev); 772 } else { 773 dev->intf = NULL; 774 up(&dev->sem); 775 } 776 777 dev_info(&intf->dev, "LD USB Device #%d now disconnected\n", 778 (minor - USB_LD_MINOR_BASE)); 779 } 780 781 /* usb specific object needed to register this driver with the usb subsystem */ 782 static struct usb_driver ld_usb_driver = { 783 .name = "ldusb", 784 .probe = ld_usb_probe, 785 .disconnect = ld_usb_disconnect, 786 .id_table = ld_usb_table, 787 }; 788 789 /** 790 * ld_usb_init 791 */ 792 static int __init ld_usb_init(void) 793 { 794 int retval; 795 796 /* register this driver with the USB subsystem */ 797 retval = usb_register(&ld_usb_driver); 798 if (retval) 799 err("usb_register failed for the "__FILE__" driver. Error number %d\n", retval); 800 801 return retval; 802 } 803 804 /** 805 * ld_usb_exit 806 */ 807 static void __exit ld_usb_exit(void) 808 { 809 /* deregister this driver with the USB subsystem */ 810 usb_deregister(&ld_usb_driver); 811 } 812 813 module_init(ld_usb_init); 814 module_exit(ld_usb_exit); 815 816