1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * adutux - driver for ADU devices from Ontrak Control Systems 4 * This is an experimental driver. Use at your own risk. 5 * This driver is not supported by Ontrak Control Systems. 6 * 7 * Copyright (c) 2003 John Homppi (SCO, leave this notice here) 8 * 9 * derived from the Lego USB Tower driver 0.56: 10 * Copyright (c) 2003 David Glance <davidgsf@sourceforge.net> 11 * 2001 Juergen Stuber <stuber@loria.fr> 12 * that was derived from USB Skeleton driver - 0.5 13 * Copyright (c) 2001 Greg Kroah-Hartman (greg@kroah.com) 14 * 15 */ 16 17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 18 19 #include <linux/kernel.h> 20 #include <linux/sched/signal.h> 21 #include <linux/errno.h> 22 #include <linux/slab.h> 23 #include <linux/module.h> 24 #include <linux/usb.h> 25 #include <linux/mutex.h> 26 #include <linux/uaccess.h> 27 28 #define DRIVER_AUTHOR "John Homppi" 29 #define DRIVER_DESC "adutux (see www.ontrak.net)" 30 31 /* Define these values to match your device */ 32 #define ADU_VENDOR_ID 0x0a07 33 #define ADU_PRODUCT_ID 0x0064 34 35 /* table of devices that work with this driver */ 36 static const struct usb_device_id device_table[] = { 37 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID) }, /* ADU100 */ 38 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+20) }, /* ADU120 */ 39 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+30) }, /* ADU130 */ 40 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+100) }, /* ADU200 */ 41 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+108) }, /* ADU208 */ 42 { USB_DEVICE(ADU_VENDOR_ID, ADU_PRODUCT_ID+118) }, /* ADU218 */ 43 { } /* Terminating entry */ 44 }; 45 46 MODULE_DEVICE_TABLE(usb, device_table); 47 48 #ifdef CONFIG_USB_DYNAMIC_MINORS 49 #define ADU_MINOR_BASE 0 50 #else 51 #define ADU_MINOR_BASE 67 52 #endif 53 54 /* we can have up to this number of device plugged in at once */ 55 #define MAX_DEVICES 16 56 57 #define COMMAND_TIMEOUT (2*HZ) 58 59 /* 60 * The locking scheme is a vanilla 3-lock: 61 * adu_device.buflock: A spinlock, covers what IRQs touch. 62 * adutux_mutex: A Static lock to cover open_count. It would also cover 63 * any globals, but we don't have them in 2.6. 64 * adu_device.mtx: A mutex to hold across sleepers like copy_from_user. 65 * It covers all of adu_device, except the open_count 66 * and what .buflock covers. 67 */ 68 69 /* Structure to hold all of our device specific stuff */ 70 struct adu_device { 71 struct mutex mtx; 72 struct usb_device *udev; /* save off the usb device pointer */ 73 struct usb_interface *interface; 74 unsigned int minor; /* the starting minor number for this device */ 75 char serial_number[8]; 76 77 int open_count; /* number of times this port has been opened */ 78 79 char *read_buffer_primary; 80 int read_buffer_length; 81 char *read_buffer_secondary; 82 int secondary_head; 83 int secondary_tail; 84 spinlock_t buflock; 85 86 wait_queue_head_t read_wait; 87 wait_queue_head_t write_wait; 88 89 char *interrupt_in_buffer; 90 struct usb_endpoint_descriptor *interrupt_in_endpoint; 91 struct urb *interrupt_in_urb; 92 int read_urb_finished; 93 94 char *interrupt_out_buffer; 95 struct usb_endpoint_descriptor *interrupt_out_endpoint; 96 struct urb *interrupt_out_urb; 97 int out_urb_finished; 98 }; 99 100 static DEFINE_MUTEX(adutux_mutex); 101 102 static struct usb_driver adu_driver; 103 104 static inline void adu_debug_data(struct device *dev, const char *function, 105 int size, const unsigned char *data) 106 { 107 dev_dbg(dev, "%s - length = %d, data = %*ph\n", 108 function, size, size, data); 109 } 110 111 /** 112 * adu_abort_transfers 113 * aborts transfers and frees associated data structures 114 */ 115 static void adu_abort_transfers(struct adu_device *dev) 116 { 117 unsigned long flags; 118 119 if (dev->udev == NULL) 120 return; 121 122 /* shutdown transfer */ 123 124 /* XXX Anchor these instead */ 125 spin_lock_irqsave(&dev->buflock, flags); 126 if (!dev->read_urb_finished) { 127 spin_unlock_irqrestore(&dev->buflock, flags); 128 usb_kill_urb(dev->interrupt_in_urb); 129 } else 130 spin_unlock_irqrestore(&dev->buflock, flags); 131 132 spin_lock_irqsave(&dev->buflock, flags); 133 if (!dev->out_urb_finished) { 134 spin_unlock_irqrestore(&dev->buflock, flags); 135 wait_event_timeout(dev->write_wait, dev->out_urb_finished, 136 COMMAND_TIMEOUT); 137 usb_kill_urb(dev->interrupt_out_urb); 138 } else 139 spin_unlock_irqrestore(&dev->buflock, flags); 140 } 141 142 static void adu_delete(struct adu_device *dev) 143 { 144 /* free data structures */ 145 usb_free_urb(dev->interrupt_in_urb); 146 usb_free_urb(dev->interrupt_out_urb); 147 kfree(dev->read_buffer_primary); 148 kfree(dev->read_buffer_secondary); 149 kfree(dev->interrupt_in_buffer); 150 kfree(dev->interrupt_out_buffer); 151 kfree(dev); 152 } 153 154 static void adu_interrupt_in_callback(struct urb *urb) 155 { 156 struct adu_device *dev = urb->context; 157 int status = urb->status; 158 unsigned long flags; 159 160 adu_debug_data(&dev->udev->dev, __func__, 161 urb->actual_length, urb->transfer_buffer); 162 163 spin_lock_irqsave(&dev->buflock, flags); 164 165 if (status != 0) { 166 if ((status != -ENOENT) && (status != -ECONNRESET) && 167 (status != -ESHUTDOWN)) { 168 dev_dbg(&dev->udev->dev, 169 "%s : nonzero status received: %d\n", 170 __func__, status); 171 } 172 goto exit; 173 } 174 175 if (urb->actual_length > 0 && dev->interrupt_in_buffer[0] != 0x00) { 176 if (dev->read_buffer_length < 177 (4 * usb_endpoint_maxp(dev->interrupt_in_endpoint)) - 178 (urb->actual_length)) { 179 memcpy (dev->read_buffer_primary + 180 dev->read_buffer_length, 181 dev->interrupt_in_buffer, urb->actual_length); 182 183 dev->read_buffer_length += urb->actual_length; 184 dev_dbg(&dev->udev->dev,"%s reading %d\n", __func__, 185 urb->actual_length); 186 } else { 187 dev_dbg(&dev->udev->dev,"%s : read_buffer overflow\n", 188 __func__); 189 } 190 } 191 192 exit: 193 dev->read_urb_finished = 1; 194 spin_unlock_irqrestore(&dev->buflock, flags); 195 /* always wake up so we recover from errors */ 196 wake_up_interruptible(&dev->read_wait); 197 } 198 199 static void adu_interrupt_out_callback(struct urb *urb) 200 { 201 struct adu_device *dev = urb->context; 202 int status = urb->status; 203 unsigned long flags; 204 205 adu_debug_data(&dev->udev->dev, __func__, 206 urb->actual_length, urb->transfer_buffer); 207 208 if (status != 0) { 209 if ((status != -ENOENT) && 210 (status != -ECONNRESET)) { 211 dev_dbg(&dev->udev->dev, 212 "%s :nonzero status received: %d\n", __func__, 213 status); 214 } 215 return; 216 } 217 218 spin_lock_irqsave(&dev->buflock, flags); 219 dev->out_urb_finished = 1; 220 wake_up(&dev->write_wait); 221 spin_unlock_irqrestore(&dev->buflock, flags); 222 } 223 224 static int adu_open(struct inode *inode, struct file *file) 225 { 226 struct adu_device *dev = NULL; 227 struct usb_interface *interface; 228 int subminor; 229 int retval; 230 231 subminor = iminor(inode); 232 233 retval = mutex_lock_interruptible(&adutux_mutex); 234 if (retval) 235 goto exit_no_lock; 236 237 interface = usb_find_interface(&adu_driver, subminor); 238 if (!interface) { 239 pr_err("%s - error, can't find device for minor %d\n", 240 __func__, subminor); 241 retval = -ENODEV; 242 goto exit_no_device; 243 } 244 245 dev = usb_get_intfdata(interface); 246 if (!dev || !dev->udev) { 247 retval = -ENODEV; 248 goto exit_no_device; 249 } 250 251 /* check that nobody else is using the device */ 252 if (dev->open_count) { 253 retval = -EBUSY; 254 goto exit_no_device; 255 } 256 257 ++dev->open_count; 258 dev_dbg(&dev->udev->dev, "%s: open count %d\n", __func__, 259 dev->open_count); 260 261 /* save device in the file's private structure */ 262 file->private_data = dev; 263 264 /* initialize in direction */ 265 dev->read_buffer_length = 0; 266 267 /* fixup first read by having urb waiting for it */ 268 usb_fill_int_urb(dev->interrupt_in_urb, dev->udev, 269 usb_rcvintpipe(dev->udev, 270 dev->interrupt_in_endpoint->bEndpointAddress), 271 dev->interrupt_in_buffer, 272 usb_endpoint_maxp(dev->interrupt_in_endpoint), 273 adu_interrupt_in_callback, dev, 274 dev->interrupt_in_endpoint->bInterval); 275 dev->read_urb_finished = 0; 276 if (usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL)) 277 dev->read_urb_finished = 1; 278 /* we ignore failure */ 279 /* end of fixup for first read */ 280 281 /* initialize out direction */ 282 dev->out_urb_finished = 1; 283 284 retval = 0; 285 286 exit_no_device: 287 mutex_unlock(&adutux_mutex); 288 exit_no_lock: 289 return retval; 290 } 291 292 static void adu_release_internal(struct adu_device *dev) 293 { 294 /* decrement our usage count for the device */ 295 --dev->open_count; 296 dev_dbg(&dev->udev->dev, "%s : open count %d\n", __func__, 297 dev->open_count); 298 if (dev->open_count <= 0) { 299 adu_abort_transfers(dev); 300 dev->open_count = 0; 301 } 302 } 303 304 static int adu_release(struct inode *inode, struct file *file) 305 { 306 struct adu_device *dev; 307 int retval = 0; 308 309 if (file == NULL) { 310 retval = -ENODEV; 311 goto exit; 312 } 313 314 dev = file->private_data; 315 if (dev == NULL) { 316 retval = -ENODEV; 317 goto exit; 318 } 319 320 mutex_lock(&adutux_mutex); /* not interruptible */ 321 322 if (dev->open_count <= 0) { 323 dev_dbg(&dev->udev->dev, "%s : device not opened\n", __func__); 324 retval = -ENODEV; 325 goto unlock; 326 } 327 328 adu_release_internal(dev); 329 if (dev->udev == NULL) { 330 /* the device was unplugged before the file was released */ 331 if (!dev->open_count) /* ... and we're the last user */ 332 adu_delete(dev); 333 } 334 unlock: 335 mutex_unlock(&adutux_mutex); 336 exit: 337 return retval; 338 } 339 340 static ssize_t adu_read(struct file *file, __user char *buffer, size_t count, 341 loff_t *ppos) 342 { 343 struct adu_device *dev; 344 size_t bytes_read = 0; 345 size_t bytes_to_read = count; 346 int i; 347 int retval = 0; 348 int timeout = 0; 349 int should_submit = 0; 350 unsigned long flags; 351 DECLARE_WAITQUEUE(wait, current); 352 353 dev = file->private_data; 354 if (mutex_lock_interruptible(&dev->mtx)) 355 return -ERESTARTSYS; 356 357 /* verify that the device wasn't unplugged */ 358 if (dev->udev == NULL) { 359 retval = -ENODEV; 360 pr_err("No device or device unplugged %d\n", retval); 361 goto exit; 362 } 363 364 /* verify that some data was requested */ 365 if (count == 0) { 366 dev_dbg(&dev->udev->dev, "%s : read request of 0 bytes\n", 367 __func__); 368 goto exit; 369 } 370 371 timeout = COMMAND_TIMEOUT; 372 dev_dbg(&dev->udev->dev, "%s : about to start looping\n", __func__); 373 while (bytes_to_read) { 374 int data_in_secondary = dev->secondary_tail - dev->secondary_head; 375 dev_dbg(&dev->udev->dev, 376 "%s : while, data_in_secondary=%d, status=%d\n", 377 __func__, data_in_secondary, 378 dev->interrupt_in_urb->status); 379 380 if (data_in_secondary) { 381 /* drain secondary buffer */ 382 int amount = bytes_to_read < data_in_secondary ? bytes_to_read : data_in_secondary; 383 i = copy_to_user(buffer, dev->read_buffer_secondary+dev->secondary_head, amount); 384 if (i) { 385 retval = -EFAULT; 386 goto exit; 387 } 388 dev->secondary_head += (amount - i); 389 bytes_read += (amount - i); 390 bytes_to_read -= (amount - i); 391 } else { 392 /* we check the primary buffer */ 393 spin_lock_irqsave (&dev->buflock, flags); 394 if (dev->read_buffer_length) { 395 /* we secure access to the primary */ 396 char *tmp; 397 dev_dbg(&dev->udev->dev, 398 "%s : swap, read_buffer_length = %d\n", 399 __func__, dev->read_buffer_length); 400 tmp = dev->read_buffer_secondary; 401 dev->read_buffer_secondary = dev->read_buffer_primary; 402 dev->read_buffer_primary = tmp; 403 dev->secondary_head = 0; 404 dev->secondary_tail = dev->read_buffer_length; 405 dev->read_buffer_length = 0; 406 spin_unlock_irqrestore(&dev->buflock, flags); 407 /* we have a free buffer so use it */ 408 should_submit = 1; 409 } else { 410 /* even the primary was empty - we may need to do IO */ 411 if (!dev->read_urb_finished) { 412 /* somebody is doing IO */ 413 spin_unlock_irqrestore(&dev->buflock, flags); 414 dev_dbg(&dev->udev->dev, 415 "%s : submitted already\n", 416 __func__); 417 } else { 418 /* we must initiate input */ 419 dev_dbg(&dev->udev->dev, 420 "%s : initiate input\n", 421 __func__); 422 dev->read_urb_finished = 0; 423 spin_unlock_irqrestore(&dev->buflock, flags); 424 425 usb_fill_int_urb(dev->interrupt_in_urb, dev->udev, 426 usb_rcvintpipe(dev->udev, 427 dev->interrupt_in_endpoint->bEndpointAddress), 428 dev->interrupt_in_buffer, 429 usb_endpoint_maxp(dev->interrupt_in_endpoint), 430 adu_interrupt_in_callback, 431 dev, 432 dev->interrupt_in_endpoint->bInterval); 433 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 434 if (retval) { 435 dev->read_urb_finished = 1; 436 if (retval == -ENOMEM) { 437 retval = bytes_read ? bytes_read : -ENOMEM; 438 } 439 dev_dbg(&dev->udev->dev, 440 "%s : submit failed\n", 441 __func__); 442 goto exit; 443 } 444 } 445 446 /* we wait for I/O to complete */ 447 set_current_state(TASK_INTERRUPTIBLE); 448 add_wait_queue(&dev->read_wait, &wait); 449 spin_lock_irqsave(&dev->buflock, flags); 450 if (!dev->read_urb_finished) { 451 spin_unlock_irqrestore(&dev->buflock, flags); 452 timeout = schedule_timeout(COMMAND_TIMEOUT); 453 } else { 454 spin_unlock_irqrestore(&dev->buflock, flags); 455 set_current_state(TASK_RUNNING); 456 } 457 remove_wait_queue(&dev->read_wait, &wait); 458 459 if (timeout <= 0) { 460 dev_dbg(&dev->udev->dev, 461 "%s : timeout\n", __func__); 462 retval = bytes_read ? bytes_read : -ETIMEDOUT; 463 goto exit; 464 } 465 466 if (signal_pending(current)) { 467 dev_dbg(&dev->udev->dev, 468 "%s : signal pending\n", 469 __func__); 470 retval = bytes_read ? bytes_read : -EINTR; 471 goto exit; 472 } 473 } 474 } 475 } 476 477 retval = bytes_read; 478 /* if the primary buffer is empty then use it */ 479 spin_lock_irqsave(&dev->buflock, flags); 480 if (should_submit && dev->read_urb_finished) { 481 dev->read_urb_finished = 0; 482 spin_unlock_irqrestore(&dev->buflock, flags); 483 usb_fill_int_urb(dev->interrupt_in_urb, dev->udev, 484 usb_rcvintpipe(dev->udev, 485 dev->interrupt_in_endpoint->bEndpointAddress), 486 dev->interrupt_in_buffer, 487 usb_endpoint_maxp(dev->interrupt_in_endpoint), 488 adu_interrupt_in_callback, 489 dev, 490 dev->interrupt_in_endpoint->bInterval); 491 if (usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL) != 0) 492 dev->read_urb_finished = 1; 493 /* we ignore failure */ 494 } else { 495 spin_unlock_irqrestore(&dev->buflock, flags); 496 } 497 498 exit: 499 /* unlock the device */ 500 mutex_unlock(&dev->mtx); 501 502 return retval; 503 } 504 505 static ssize_t adu_write(struct file *file, const __user char *buffer, 506 size_t count, loff_t *ppos) 507 { 508 DECLARE_WAITQUEUE(waita, current); 509 struct adu_device *dev; 510 size_t bytes_written = 0; 511 size_t bytes_to_write; 512 size_t buffer_size; 513 unsigned long flags; 514 int retval; 515 516 dev = file->private_data; 517 518 retval = mutex_lock_interruptible(&dev->mtx); 519 if (retval) 520 goto exit_nolock; 521 522 /* verify that the device wasn't unplugged */ 523 if (dev->udev == NULL) { 524 retval = -ENODEV; 525 pr_err("No device or device unplugged %d\n", retval); 526 goto exit; 527 } 528 529 /* verify that we actually have some data to write */ 530 if (count == 0) { 531 dev_dbg(&dev->udev->dev, "%s : write request of 0 bytes\n", 532 __func__); 533 goto exit; 534 } 535 536 while (count > 0) { 537 add_wait_queue(&dev->write_wait, &waita); 538 set_current_state(TASK_INTERRUPTIBLE); 539 spin_lock_irqsave(&dev->buflock, flags); 540 if (!dev->out_urb_finished) { 541 spin_unlock_irqrestore(&dev->buflock, flags); 542 543 mutex_unlock(&dev->mtx); 544 if (signal_pending(current)) { 545 dev_dbg(&dev->udev->dev, "%s : interrupted\n", 546 __func__); 547 set_current_state(TASK_RUNNING); 548 retval = -EINTR; 549 goto exit_onqueue; 550 } 551 if (schedule_timeout(COMMAND_TIMEOUT) == 0) { 552 dev_dbg(&dev->udev->dev, 553 "%s - command timed out.\n", __func__); 554 retval = -ETIMEDOUT; 555 goto exit_onqueue; 556 } 557 remove_wait_queue(&dev->write_wait, &waita); 558 retval = mutex_lock_interruptible(&dev->mtx); 559 if (retval) { 560 retval = bytes_written ? bytes_written : retval; 561 goto exit_nolock; 562 } 563 564 dev_dbg(&dev->udev->dev, 565 "%s : in progress, count = %zd\n", 566 __func__, count); 567 } else { 568 spin_unlock_irqrestore(&dev->buflock, flags); 569 set_current_state(TASK_RUNNING); 570 remove_wait_queue(&dev->write_wait, &waita); 571 dev_dbg(&dev->udev->dev, "%s : sending, count = %zd\n", 572 __func__, count); 573 574 /* write the data into interrupt_out_buffer from userspace */ 575 buffer_size = usb_endpoint_maxp(dev->interrupt_out_endpoint); 576 bytes_to_write = count > buffer_size ? buffer_size : count; 577 dev_dbg(&dev->udev->dev, 578 "%s : buffer_size = %zd, count = %zd, bytes_to_write = %zd\n", 579 __func__, buffer_size, count, bytes_to_write); 580 581 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write) != 0) { 582 retval = -EFAULT; 583 goto exit; 584 } 585 586 /* send off the urb */ 587 usb_fill_int_urb( 588 dev->interrupt_out_urb, 589 dev->udev, 590 usb_sndintpipe(dev->udev, dev->interrupt_out_endpoint->bEndpointAddress), 591 dev->interrupt_out_buffer, 592 bytes_to_write, 593 adu_interrupt_out_callback, 594 dev, 595 dev->interrupt_out_endpoint->bInterval); 596 dev->interrupt_out_urb->actual_length = bytes_to_write; 597 dev->out_urb_finished = 0; 598 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL); 599 if (retval < 0) { 600 dev->out_urb_finished = 1; 601 dev_err(&dev->udev->dev, "Couldn't submit " 602 "interrupt_out_urb %d\n", retval); 603 goto exit; 604 } 605 606 buffer += bytes_to_write; 607 count -= bytes_to_write; 608 609 bytes_written += bytes_to_write; 610 } 611 } 612 mutex_unlock(&dev->mtx); 613 return bytes_written; 614 615 exit: 616 mutex_unlock(&dev->mtx); 617 exit_nolock: 618 return retval; 619 620 exit_onqueue: 621 remove_wait_queue(&dev->write_wait, &waita); 622 return retval; 623 } 624 625 /* file operations needed when we register this driver */ 626 static const struct file_operations adu_fops = { 627 .owner = THIS_MODULE, 628 .read = adu_read, 629 .write = adu_write, 630 .open = adu_open, 631 .release = adu_release, 632 .llseek = noop_llseek, 633 }; 634 635 /* 636 * usb class driver info in order to get a minor number from the usb core, 637 * and to have the device registered with devfs and the driver core 638 */ 639 static struct usb_class_driver adu_class = { 640 .name = "usb/adutux%d", 641 .fops = &adu_fops, 642 .minor_base = ADU_MINOR_BASE, 643 }; 644 645 /** 646 * adu_probe 647 * 648 * Called by the usb core when a new device is connected that it thinks 649 * this driver might be interested in. 650 */ 651 static int adu_probe(struct usb_interface *interface, 652 const struct usb_device_id *id) 653 { 654 struct usb_device *udev = interface_to_usbdev(interface); 655 struct adu_device *dev = NULL; 656 int retval = -ENOMEM; 657 int in_end_size; 658 int out_end_size; 659 int res; 660 661 /* allocate memory for our device state and initialize it */ 662 dev = kzalloc(sizeof(struct adu_device), GFP_KERNEL); 663 if (!dev) 664 return -ENOMEM; 665 666 mutex_init(&dev->mtx); 667 spin_lock_init(&dev->buflock); 668 dev->udev = udev; 669 init_waitqueue_head(&dev->read_wait); 670 init_waitqueue_head(&dev->write_wait); 671 672 res = usb_find_common_endpoints_reverse(&interface->altsetting[0], 673 NULL, NULL, 674 &dev->interrupt_in_endpoint, 675 &dev->interrupt_out_endpoint); 676 if (res) { 677 dev_err(&interface->dev, "interrupt endpoints not found\n"); 678 retval = res; 679 goto error; 680 } 681 682 in_end_size = usb_endpoint_maxp(dev->interrupt_in_endpoint); 683 out_end_size = usb_endpoint_maxp(dev->interrupt_out_endpoint); 684 685 dev->read_buffer_primary = kmalloc((4 * in_end_size), GFP_KERNEL); 686 if (!dev->read_buffer_primary) 687 goto error; 688 689 /* debug code prime the buffer */ 690 memset(dev->read_buffer_primary, 'a', in_end_size); 691 memset(dev->read_buffer_primary + in_end_size, 'b', in_end_size); 692 memset(dev->read_buffer_primary + (2 * in_end_size), 'c', in_end_size); 693 memset(dev->read_buffer_primary + (3 * in_end_size), 'd', in_end_size); 694 695 dev->read_buffer_secondary = kmalloc((4 * in_end_size), GFP_KERNEL); 696 if (!dev->read_buffer_secondary) 697 goto error; 698 699 /* debug code prime the buffer */ 700 memset(dev->read_buffer_secondary, 'e', in_end_size); 701 memset(dev->read_buffer_secondary + in_end_size, 'f', in_end_size); 702 memset(dev->read_buffer_secondary + (2 * in_end_size), 'g', in_end_size); 703 memset(dev->read_buffer_secondary + (3 * in_end_size), 'h', in_end_size); 704 705 dev->interrupt_in_buffer = kmalloc(in_end_size, GFP_KERNEL); 706 if (!dev->interrupt_in_buffer) 707 goto error; 708 709 /* debug code prime the buffer */ 710 memset(dev->interrupt_in_buffer, 'i', in_end_size); 711 712 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL); 713 if (!dev->interrupt_in_urb) 714 goto error; 715 dev->interrupt_out_buffer = kmalloc(out_end_size, GFP_KERNEL); 716 if (!dev->interrupt_out_buffer) 717 goto error; 718 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL); 719 if (!dev->interrupt_out_urb) 720 goto error; 721 722 if (!usb_string(udev, udev->descriptor.iSerialNumber, dev->serial_number, 723 sizeof(dev->serial_number))) { 724 dev_err(&interface->dev, "Could not retrieve serial number\n"); 725 retval = -EIO; 726 goto error; 727 } 728 dev_dbg(&interface->dev,"serial_number=%s", dev->serial_number); 729 730 /* we can register the device now, as it is ready */ 731 usb_set_intfdata(interface, dev); 732 733 retval = usb_register_dev(interface, &adu_class); 734 735 if (retval) { 736 /* something prevented us from registering this driver */ 737 dev_err(&interface->dev, "Not able to get a minor for this device.\n"); 738 usb_set_intfdata(interface, NULL); 739 goto error; 740 } 741 742 dev->minor = interface->minor; 743 744 /* let the user know what node this device is now attached to */ 745 dev_info(&interface->dev, "ADU%d %s now attached to /dev/usb/adutux%d\n", 746 le16_to_cpu(udev->descriptor.idProduct), dev->serial_number, 747 (dev->minor - ADU_MINOR_BASE)); 748 749 return 0; 750 751 error: 752 adu_delete(dev); 753 return retval; 754 } 755 756 /** 757 * adu_disconnect 758 * 759 * Called by the usb core when the device is removed from the system. 760 */ 761 static void adu_disconnect(struct usb_interface *interface) 762 { 763 struct adu_device *dev; 764 765 dev = usb_get_intfdata(interface); 766 767 mutex_lock(&dev->mtx); /* not interruptible */ 768 dev->udev = NULL; /* poison */ 769 usb_deregister_dev(interface, &adu_class); 770 mutex_unlock(&dev->mtx); 771 772 mutex_lock(&adutux_mutex); 773 usb_set_intfdata(interface, NULL); 774 775 /* if the device is not opened, then we clean up right now */ 776 if (!dev->open_count) 777 adu_delete(dev); 778 779 mutex_unlock(&adutux_mutex); 780 } 781 782 /* usb specific object needed to register this driver with the usb subsystem */ 783 static struct usb_driver adu_driver = { 784 .name = "adutux", 785 .probe = adu_probe, 786 .disconnect = adu_disconnect, 787 .id_table = device_table, 788 }; 789 790 module_usb_driver(adu_driver); 791 792 MODULE_AUTHOR(DRIVER_AUTHOR); 793 MODULE_DESCRIPTION(DRIVER_DESC); 794 MODULE_LICENSE("GPL"); 795