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; 168 169 char* interrupt_out_buffer; 170 struct usb_endpoint_descriptor* interrupt_out_endpoint; 171 struct urb* interrupt_out_urb; 172 int interrupt_out_interval; 173 size_t interrupt_out_endpoint_size; 174 int interrupt_out_busy; 175 }; 176 177 /* prevent races between open() and disconnect() */ 178 static DEFINE_MUTEX(disconnect_mutex); 179 180 static struct usb_driver ld_usb_driver; 181 182 /** 183 * ld_usb_abort_transfers 184 * aborts transfers and frees associated data structures 185 */ 186 static void ld_usb_abort_transfers(struct ld_usb *dev) 187 { 188 /* shutdown transfer */ 189 if (dev->interrupt_in_running) { 190 dev->interrupt_in_running = 0; 191 if (dev->intf) 192 usb_kill_urb(dev->interrupt_in_urb); 193 } 194 if (dev->interrupt_out_busy) 195 if (dev->intf) 196 usb_kill_urb(dev->interrupt_out_urb); 197 } 198 199 /** 200 * ld_usb_delete 201 */ 202 static void ld_usb_delete(struct ld_usb *dev) 203 { 204 ld_usb_abort_transfers(dev); 205 206 /* free data structures */ 207 usb_free_urb(dev->interrupt_in_urb); 208 usb_free_urb(dev->interrupt_out_urb); 209 kfree(dev->ring_buffer); 210 kfree(dev->interrupt_in_buffer); 211 kfree(dev->interrupt_out_buffer); 212 kfree(dev); 213 } 214 215 /** 216 * ld_usb_interrupt_in_callback 217 */ 218 static void ld_usb_interrupt_in_callback(struct urb *urb) 219 { 220 struct ld_usb *dev = urb->context; 221 size_t *actual_buffer; 222 unsigned int next_ring_head; 223 int retval; 224 225 if (urb->status) { 226 if (urb->status == -ENOENT || 227 urb->status == -ECONNRESET || 228 urb->status == -ESHUTDOWN) { 229 goto exit; 230 } else { 231 dbg_info(&dev->intf->dev, "%s: nonzero status received: %d\n", 232 __FUNCTION__, urb->status); 233 goto resubmit; /* maybe we can recover */ 234 } 235 } 236 237 if (urb->actual_length > 0) { 238 next_ring_head = (dev->ring_head+1) % ring_buffer_size; 239 if (next_ring_head != dev->ring_tail) { 240 actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_head*(sizeof(size_t)+dev->interrupt_in_endpoint_size)); 241 /* actual_buffer gets urb->actual_length + interrupt_in_buffer */ 242 *actual_buffer = urb->actual_length; 243 memcpy(actual_buffer+1, dev->interrupt_in_buffer, urb->actual_length); 244 dev->ring_head = next_ring_head; 245 dbg_info(&dev->intf->dev, "%s: received %d bytes\n", 246 __FUNCTION__, urb->actual_length); 247 } else 248 dev_warn(&dev->intf->dev, 249 "Ring buffer overflow, %d bytes dropped\n", 250 urb->actual_length); 251 } 252 253 resubmit: 254 /* resubmit if we're still running */ 255 if (dev->interrupt_in_running && dev->intf) { 256 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_ATOMIC); 257 if (retval) 258 dev_err(&dev->intf->dev, 259 "usb_submit_urb failed (%d)\n", retval); 260 } 261 262 exit: 263 dev->interrupt_in_done = 1; 264 wake_up_interruptible(&dev->read_wait); 265 } 266 267 /** 268 * ld_usb_interrupt_out_callback 269 */ 270 static void ld_usb_interrupt_out_callback(struct urb *urb) 271 { 272 struct ld_usb *dev = urb->context; 273 274 /* sync/async unlink faults aren't errors */ 275 if (urb->status && !(urb->status == -ENOENT || 276 urb->status == -ECONNRESET || 277 urb->status == -ESHUTDOWN)) 278 dbg_info(&dev->intf->dev, 279 "%s - nonzero write interrupt status received: %d\n", 280 __FUNCTION__, urb->status); 281 282 dev->interrupt_out_busy = 0; 283 wake_up_interruptible(&dev->write_wait); 284 } 285 286 /** 287 * ld_usb_open 288 */ 289 static int ld_usb_open(struct inode *inode, struct file *file) 290 { 291 struct ld_usb *dev; 292 int subminor; 293 int retval = 0; 294 struct usb_interface *interface; 295 296 nonseekable_open(inode, file); 297 subminor = iminor(inode); 298 299 mutex_lock(&disconnect_mutex); 300 301 interface = usb_find_interface(&ld_usb_driver, subminor); 302 303 if (!interface) { 304 err("%s - error, can't find device for minor %d\n", 305 __FUNCTION__, subminor); 306 retval = -ENODEV; 307 goto unlock_disconnect_exit; 308 } 309 310 dev = usb_get_intfdata(interface); 311 312 if (!dev) { 313 retval = -ENODEV; 314 goto unlock_disconnect_exit; 315 } 316 317 /* lock this device */ 318 if (down_interruptible(&dev->sem)) { 319 retval = -ERESTARTSYS; 320 goto unlock_disconnect_exit; 321 } 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 usb_fill_int_urb(dev->interrupt_in_urb, 334 interface_to_usbdev(interface), 335 usb_rcvintpipe(interface_to_usbdev(interface), 336 dev->interrupt_in_endpoint->bEndpointAddress), 337 dev->interrupt_in_buffer, 338 dev->interrupt_in_endpoint_size, 339 ld_usb_interrupt_in_callback, 340 dev, 341 dev->interrupt_in_interval); 342 343 dev->interrupt_in_running = 1; 344 dev->interrupt_in_done = 0; 345 346 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 347 if (retval) { 348 dev_err(&interface->dev, "Couldn't submit interrupt_in_urb %d\n", retval); 349 dev->interrupt_in_running = 0; 350 dev->open_count = 0; 351 goto unlock_exit; 352 } 353 354 /* save device in the file's private structure */ 355 file->private_data = dev; 356 357 unlock_exit: 358 up(&dev->sem); 359 360 unlock_disconnect_exit: 361 mutex_unlock(&disconnect_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 (down_interruptible(&dev->sem)) { 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 up(&dev->sem); 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 up(&dev->sem); 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; 442 443 dev = file->private_data; 444 445 /* verify that we actually have some data to read */ 446 if (count == 0) 447 goto exit; 448 449 /* lock this object */ 450 if (down_interruptible(&dev->sem)) { 451 retval = -ERESTARTSYS; 452 goto exit; 453 } 454 455 /* verify that the device wasn't unplugged */ 456 if (dev->intf == NULL) { 457 retval = -ENODEV; 458 err("No device or device unplugged %d\n", retval); 459 goto unlock_exit; 460 } 461 462 /* wait for data */ 463 if (dev->ring_head == dev->ring_tail) { 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 } 472 473 /* actual_buffer contains actual_length + interrupt_in_buffer */ 474 actual_buffer = (size_t*)(dev->ring_buffer + dev->ring_tail*(sizeof(size_t)+dev->interrupt_in_endpoint_size)); 475 bytes_to_read = min(count, *actual_buffer); 476 if (bytes_to_read < *actual_buffer) 477 dev_warn(&dev->intf->dev, "Read buffer overflow, %zd bytes dropped\n", 478 *actual_buffer-bytes_to_read); 479 480 /* copy one interrupt_in_buffer from ring_buffer into userspace */ 481 if (copy_to_user(buffer, actual_buffer+1, bytes_to_read)) { 482 retval = -EFAULT; 483 goto unlock_exit; 484 } 485 dev->ring_tail = (dev->ring_tail+1) % ring_buffer_size; 486 487 retval = bytes_to_read; 488 489 unlock_exit: 490 /* unlock the device */ 491 up(&dev->sem); 492 493 exit: 494 return retval; 495 } 496 497 /** 498 * ld_usb_write 499 */ 500 static ssize_t ld_usb_write(struct file *file, const char __user *buffer, 501 size_t count, loff_t *ppos) 502 { 503 struct ld_usb *dev; 504 size_t bytes_to_write; 505 int retval = 0; 506 507 dev = file->private_data; 508 509 /* verify that we actually have some data to write */ 510 if (count == 0) 511 goto exit; 512 513 /* lock this object */ 514 if (down_interruptible(&dev->sem)) { 515 retval = -ERESTARTSYS; 516 goto exit; 517 } 518 519 /* verify that the device wasn't unplugged */ 520 if (dev->intf == NULL) { 521 retval = -ENODEV; 522 err("No device or device unplugged %d\n", retval); 523 goto unlock_exit; 524 } 525 526 /* wait until previous transfer is finished */ 527 if (dev->interrupt_out_busy) { 528 if (file->f_flags & O_NONBLOCK) { 529 retval = -EAGAIN; 530 goto unlock_exit; 531 } 532 retval = wait_event_interruptible(dev->write_wait, !dev->interrupt_out_busy); 533 if (retval < 0) { 534 goto unlock_exit; 535 } 536 } 537 538 /* write the data into interrupt_out_buffer from userspace */ 539 bytes_to_write = min(count, write_buffer_size*dev->interrupt_out_endpoint_size); 540 if (bytes_to_write < count) 541 dev_warn(&dev->intf->dev, "Write buffer overflow, %zd bytes dropped\n",count-bytes_to_write); 542 dbg_info(&dev->intf->dev, "%s: count = %zd, bytes_to_write = %zd\n", __FUNCTION__, count, bytes_to_write); 543 544 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write)) { 545 retval = -EFAULT; 546 goto unlock_exit; 547 } 548 549 if (dev->interrupt_out_endpoint == NULL) { 550 /* try HID_REQ_SET_REPORT=9 on control_endpoint instead of interrupt_out_endpoint */ 551 retval = usb_control_msg(interface_to_usbdev(dev->intf), 552 usb_sndctrlpipe(interface_to_usbdev(dev->intf), 0), 553 9, 554 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT, 555 1 << 8, 0, 556 dev->interrupt_out_buffer, 557 bytes_to_write, 558 USB_CTRL_SET_TIMEOUT * HZ); 559 if (retval < 0) 560 err("Couldn't submit HID_REQ_SET_REPORT %d\n", retval); 561 goto unlock_exit; 562 } 563 564 /* send off the urb */ 565 usb_fill_int_urb(dev->interrupt_out_urb, 566 interface_to_usbdev(dev->intf), 567 usb_sndintpipe(interface_to_usbdev(dev->intf), 568 dev->interrupt_out_endpoint->bEndpointAddress), 569 dev->interrupt_out_buffer, 570 bytes_to_write, 571 ld_usb_interrupt_out_callback, 572 dev, 573 dev->interrupt_out_interval); 574 575 dev->interrupt_out_busy = 1; 576 wmb(); 577 578 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL); 579 if (retval) { 580 dev->interrupt_out_busy = 0; 581 err("Couldn't submit interrupt_out_urb %d\n", retval); 582 goto unlock_exit; 583 } 584 retval = bytes_to_write; 585 586 unlock_exit: 587 /* unlock the device */ 588 up(&dev->sem); 589 590 exit: 591 return retval; 592 } 593 594 /* file operations needed when we register this driver */ 595 static const struct file_operations ld_usb_fops = { 596 .owner = THIS_MODULE, 597 .read = ld_usb_read, 598 .write = ld_usb_write, 599 .open = ld_usb_open, 600 .release = ld_usb_release, 601 .poll = ld_usb_poll, 602 }; 603 604 /* 605 * usb class driver info in order to get a minor number from the usb core, 606 * and to have the device registered with the driver core 607 */ 608 static struct usb_class_driver ld_usb_class = { 609 .name = "ldusb%d", 610 .fops = &ld_usb_fops, 611 .minor_base = USB_LD_MINOR_BASE, 612 }; 613 614 /** 615 * ld_usb_probe 616 * 617 * Called by the usb core when a new device is connected that it thinks 618 * this driver might be interested in. 619 */ 620 static int ld_usb_probe(struct usb_interface *intf, const struct usb_device_id *id) 621 { 622 struct usb_device *udev = interface_to_usbdev(intf); 623 struct ld_usb *dev = NULL; 624 struct usb_host_interface *iface_desc; 625 struct usb_endpoint_descriptor *endpoint; 626 char *buffer; 627 int i; 628 int retval = -ENOMEM; 629 630 /* allocate memory for our device state and intialize it */ 631 632 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 633 if (dev == NULL) { 634 dev_err(&intf->dev, "Out of memory\n"); 635 goto exit; 636 } 637 init_MUTEX(&dev->sem); 638 dev->intf = intf; 639 init_waitqueue_head(&dev->read_wait); 640 init_waitqueue_head(&dev->write_wait); 641 642 /* workaround for early firmware versions on fast computers */ 643 if ((le16_to_cpu(udev->descriptor.idVendor) == USB_VENDOR_ID_LD) && 644 ((le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_CASSY) || 645 (le16_to_cpu(udev->descriptor.idProduct) == USB_DEVICE_ID_LD_COM3LAB)) && 646 (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x103)) { 647 buffer = kmalloc(256, GFP_KERNEL); 648 if (buffer == NULL) { 649 dev_err(&intf->dev, "Couldn't allocate string buffer\n"); 650 goto error; 651 } 652 /* usb_string makes SETUP+STALL to leave always ControlReadLoop */ 653 usb_string(udev, 255, buffer, 256); 654 kfree(buffer); 655 } 656 657 iface_desc = intf->cur_altsetting; 658 659 /* set up the endpoint information */ 660 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) { 661 endpoint = &iface_desc->endpoint[i].desc; 662 663 if (usb_endpoint_is_int_in(endpoint)) 664 dev->interrupt_in_endpoint = endpoint; 665 666 if (usb_endpoint_is_int_out(endpoint)) 667 dev->interrupt_out_endpoint = endpoint; 668 } 669 if (dev->interrupt_in_endpoint == NULL) { 670 dev_err(&intf->dev, "Interrupt in endpoint not found\n"); 671 goto error; 672 } 673 if (dev->interrupt_out_endpoint == NULL) 674 dev_warn(&intf->dev, "Interrupt out endpoint not found (using control endpoint instead)\n"); 675 676 dev->interrupt_in_endpoint_size = le16_to_cpu(dev->interrupt_in_endpoint->wMaxPacketSize); 677 dev->ring_buffer = kmalloc(ring_buffer_size*(sizeof(size_t)+dev->interrupt_in_endpoint_size), GFP_KERNEL); 678 if (!dev->ring_buffer) { 679 dev_err(&intf->dev, "Couldn't allocate ring_buffer\n"); 680 goto error; 681 } 682 dev->interrupt_in_buffer = kmalloc(dev->interrupt_in_endpoint_size, GFP_KERNEL); 683 if (!dev->interrupt_in_buffer) { 684 dev_err(&intf->dev, "Couldn't allocate interrupt_in_buffer\n"); 685 goto error; 686 } 687 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL); 688 if (!dev->interrupt_in_urb) { 689 dev_err(&intf->dev, "Couldn't allocate interrupt_in_urb\n"); 690 goto error; 691 } 692 dev->interrupt_out_endpoint_size = dev->interrupt_out_endpoint ? le16_to_cpu(dev->interrupt_out_endpoint->wMaxPacketSize) : 693 udev->descriptor.bMaxPacketSize0; 694 dev->interrupt_out_buffer = kmalloc(write_buffer_size*dev->interrupt_out_endpoint_size, GFP_KERNEL); 695 if (!dev->interrupt_out_buffer) { 696 dev_err(&intf->dev, "Couldn't allocate interrupt_out_buffer\n"); 697 goto error; 698 } 699 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL); 700 if (!dev->interrupt_out_urb) { 701 dev_err(&intf->dev, "Couldn't allocate interrupt_out_urb\n"); 702 goto error; 703 } 704 dev->interrupt_in_interval = min_interrupt_in_interval > dev->interrupt_in_endpoint->bInterval ? min_interrupt_in_interval : dev->interrupt_in_endpoint->bInterval; 705 if (dev->interrupt_out_endpoint) 706 dev->interrupt_out_interval = min_interrupt_out_interval > dev->interrupt_out_endpoint->bInterval ? min_interrupt_out_interval : dev->interrupt_out_endpoint->bInterval; 707 708 /* we can register the device now, as it is ready */ 709 usb_set_intfdata(intf, dev); 710 711 retval = usb_register_dev(intf, &ld_usb_class); 712 if (retval) { 713 /* something prevented us from registering this driver */ 714 dev_err(&intf->dev, "Not able to get a minor for this device.\n"); 715 usb_set_intfdata(intf, NULL); 716 goto error; 717 } 718 719 /* let the user know what node this device is now attached to */ 720 dev_info(&intf->dev, "LD USB Device #%d now attached to major %d minor %d\n", 721 (intf->minor - USB_LD_MINOR_BASE), USB_MAJOR, intf->minor); 722 723 exit: 724 return retval; 725 726 error: 727 ld_usb_delete(dev); 728 729 return retval; 730 } 731 732 /** 733 * ld_usb_disconnect 734 * 735 * Called by the usb core when the device is removed from the system. 736 */ 737 static void ld_usb_disconnect(struct usb_interface *intf) 738 { 739 struct ld_usb *dev; 740 int minor; 741 742 mutex_lock(&disconnect_mutex); 743 744 dev = usb_get_intfdata(intf); 745 usb_set_intfdata(intf, NULL); 746 747 down(&dev->sem); 748 749 minor = intf->minor; 750 751 /* give back our minor */ 752 usb_deregister_dev(intf, &ld_usb_class); 753 754 /* if the device is not opened, then we clean up right now */ 755 if (!dev->open_count) { 756 up(&dev->sem); 757 ld_usb_delete(dev); 758 } else { 759 dev->intf = NULL; 760 up(&dev->sem); 761 } 762 763 mutex_unlock(&disconnect_mutex); 764 765 dev_info(&intf->dev, "LD USB Device #%d now disconnected\n", 766 (minor - USB_LD_MINOR_BASE)); 767 } 768 769 /* usb specific object needed to register this driver with the usb subsystem */ 770 static struct usb_driver ld_usb_driver = { 771 .name = "ldusb", 772 .probe = ld_usb_probe, 773 .disconnect = ld_usb_disconnect, 774 .id_table = ld_usb_table, 775 }; 776 777 /** 778 * ld_usb_init 779 */ 780 static int __init ld_usb_init(void) 781 { 782 int retval; 783 784 /* register this driver with the USB subsystem */ 785 retval = usb_register(&ld_usb_driver); 786 if (retval) 787 err("usb_register failed for the "__FILE__" driver. Error number %d\n", retval); 788 789 return retval; 790 } 791 792 /** 793 * ld_usb_exit 794 */ 795 static void __exit ld_usb_exit(void) 796 { 797 /* deregister this driver with the USB subsystem */ 798 usb_deregister(&ld_usb_driver); 799 } 800 801 module_init(ld_usb_init); 802 module_exit(ld_usb_exit); 803 804