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) /* 60 second timeout for a command */ 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 usb_kill_urb(dev->interrupt_out_urb); 136 } else 137 spin_unlock_irqrestore(&dev->buflock, flags); 138 } 139 140 static void adu_delete(struct adu_device *dev) 141 { 142 /* free data structures */ 143 usb_free_urb(dev->interrupt_in_urb); 144 usb_free_urb(dev->interrupt_out_urb); 145 kfree(dev->read_buffer_primary); 146 kfree(dev->read_buffer_secondary); 147 kfree(dev->interrupt_in_buffer); 148 kfree(dev->interrupt_out_buffer); 149 kfree(dev); 150 } 151 152 static void adu_interrupt_in_callback(struct urb *urb) 153 { 154 struct adu_device *dev = urb->context; 155 int status = urb->status; 156 157 adu_debug_data(&dev->udev->dev, __func__, 158 urb->actual_length, urb->transfer_buffer); 159 160 spin_lock(&dev->buflock); 161 162 if (status != 0) { 163 if ((status != -ENOENT) && (status != -ECONNRESET) && 164 (status != -ESHUTDOWN)) { 165 dev_dbg(&dev->udev->dev, 166 "%s : nonzero status received: %d\n", 167 __func__, status); 168 } 169 goto exit; 170 } 171 172 if (urb->actual_length > 0 && dev->interrupt_in_buffer[0] != 0x00) { 173 if (dev->read_buffer_length < 174 (4 * usb_endpoint_maxp(dev->interrupt_in_endpoint)) - 175 (urb->actual_length)) { 176 memcpy (dev->read_buffer_primary + 177 dev->read_buffer_length, 178 dev->interrupt_in_buffer, urb->actual_length); 179 180 dev->read_buffer_length += urb->actual_length; 181 dev_dbg(&dev->udev->dev,"%s reading %d\n", __func__, 182 urb->actual_length); 183 } else { 184 dev_dbg(&dev->udev->dev,"%s : read_buffer overflow\n", 185 __func__); 186 } 187 } 188 189 exit: 190 dev->read_urb_finished = 1; 191 spin_unlock(&dev->buflock); 192 /* always wake up so we recover from errors */ 193 wake_up_interruptible(&dev->read_wait); 194 } 195 196 static void adu_interrupt_out_callback(struct urb *urb) 197 { 198 struct adu_device *dev = urb->context; 199 int status = urb->status; 200 201 adu_debug_data(&dev->udev->dev, __func__, 202 urb->actual_length, urb->transfer_buffer); 203 204 if (status != 0) { 205 if ((status != -ENOENT) && 206 (status != -ECONNRESET)) { 207 dev_dbg(&dev->udev->dev, 208 "%s :nonzero status received: %d\n", __func__, 209 status); 210 } 211 return; 212 } 213 214 spin_lock(&dev->buflock); 215 dev->out_urb_finished = 1; 216 wake_up(&dev->write_wait); 217 spin_unlock(&dev->buflock); 218 } 219 220 static int adu_open(struct inode *inode, struct file *file) 221 { 222 struct adu_device *dev = NULL; 223 struct usb_interface *interface; 224 int subminor; 225 int retval; 226 227 subminor = iminor(inode); 228 229 retval = mutex_lock_interruptible(&adutux_mutex); 230 if (retval) 231 goto exit_no_lock; 232 233 interface = usb_find_interface(&adu_driver, subminor); 234 if (!interface) { 235 pr_err("%s - error, can't find device for minor %d\n", 236 __func__, subminor); 237 retval = -ENODEV; 238 goto exit_no_device; 239 } 240 241 dev = usb_get_intfdata(interface); 242 if (!dev || !dev->udev) { 243 retval = -ENODEV; 244 goto exit_no_device; 245 } 246 247 /* check that nobody else is using the device */ 248 if (dev->open_count) { 249 retval = -EBUSY; 250 goto exit_no_device; 251 } 252 253 ++dev->open_count; 254 dev_dbg(&dev->udev->dev, "%s: open count %d\n", __func__, 255 dev->open_count); 256 257 /* save device in the file's private structure */ 258 file->private_data = dev; 259 260 /* initialize in direction */ 261 dev->read_buffer_length = 0; 262 263 /* fixup first read by having urb waiting for it */ 264 usb_fill_int_urb(dev->interrupt_in_urb, dev->udev, 265 usb_rcvintpipe(dev->udev, 266 dev->interrupt_in_endpoint->bEndpointAddress), 267 dev->interrupt_in_buffer, 268 usb_endpoint_maxp(dev->interrupt_in_endpoint), 269 adu_interrupt_in_callback, dev, 270 dev->interrupt_in_endpoint->bInterval); 271 dev->read_urb_finished = 0; 272 if (usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL)) 273 dev->read_urb_finished = 1; 274 /* we ignore failure */ 275 /* end of fixup for first read */ 276 277 /* initialize out direction */ 278 dev->out_urb_finished = 1; 279 280 retval = 0; 281 282 exit_no_device: 283 mutex_unlock(&adutux_mutex); 284 exit_no_lock: 285 return retval; 286 } 287 288 static void adu_release_internal(struct adu_device *dev) 289 { 290 /* decrement our usage count for the device */ 291 --dev->open_count; 292 dev_dbg(&dev->udev->dev, "%s : open count %d\n", __func__, 293 dev->open_count); 294 if (dev->open_count <= 0) { 295 adu_abort_transfers(dev); 296 dev->open_count = 0; 297 } 298 } 299 300 static int adu_release(struct inode *inode, struct file *file) 301 { 302 struct adu_device *dev; 303 int retval = 0; 304 305 if (file == NULL) { 306 retval = -ENODEV; 307 goto exit; 308 } 309 310 dev = file->private_data; 311 if (dev == NULL) { 312 retval = -ENODEV; 313 goto exit; 314 } 315 316 mutex_lock(&adutux_mutex); /* not interruptible */ 317 318 if (dev->open_count <= 0) { 319 dev_dbg(&dev->udev->dev, "%s : device not opened\n", __func__); 320 retval = -ENODEV; 321 goto unlock; 322 } 323 324 adu_release_internal(dev); 325 if (dev->udev == NULL) { 326 /* the device was unplugged before the file was released */ 327 if (!dev->open_count) /* ... and we're the last user */ 328 adu_delete(dev); 329 } 330 unlock: 331 mutex_unlock(&adutux_mutex); 332 exit: 333 return retval; 334 } 335 336 static ssize_t adu_read(struct file *file, __user char *buffer, size_t count, 337 loff_t *ppos) 338 { 339 struct adu_device *dev; 340 size_t bytes_read = 0; 341 size_t bytes_to_read = count; 342 int i; 343 int retval = 0; 344 int timeout = 0; 345 int should_submit = 0; 346 unsigned long flags; 347 DECLARE_WAITQUEUE(wait, current); 348 349 dev = file->private_data; 350 if (mutex_lock_interruptible(&dev->mtx)) 351 return -ERESTARTSYS; 352 353 /* verify that the device wasn't unplugged */ 354 if (dev->udev == NULL) { 355 retval = -ENODEV; 356 pr_err("No device or device unplugged %d\n", retval); 357 goto exit; 358 } 359 360 /* verify that some data was requested */ 361 if (count == 0) { 362 dev_dbg(&dev->udev->dev, "%s : read request of 0 bytes\n", 363 __func__); 364 goto exit; 365 } 366 367 timeout = COMMAND_TIMEOUT; 368 dev_dbg(&dev->udev->dev, "%s : about to start looping\n", __func__); 369 while (bytes_to_read) { 370 int data_in_secondary = dev->secondary_tail - dev->secondary_head; 371 dev_dbg(&dev->udev->dev, 372 "%s : while, data_in_secondary=%d, status=%d\n", 373 __func__, data_in_secondary, 374 dev->interrupt_in_urb->status); 375 376 if (data_in_secondary) { 377 /* drain secondary buffer */ 378 int amount = bytes_to_read < data_in_secondary ? bytes_to_read : data_in_secondary; 379 i = copy_to_user(buffer, dev->read_buffer_secondary+dev->secondary_head, amount); 380 if (i) { 381 retval = -EFAULT; 382 goto exit; 383 } 384 dev->secondary_head += (amount - i); 385 bytes_read += (amount - i); 386 bytes_to_read -= (amount - i); 387 } else { 388 /* we check the primary buffer */ 389 spin_lock_irqsave (&dev->buflock, flags); 390 if (dev->read_buffer_length) { 391 /* we secure access to the primary */ 392 char *tmp; 393 dev_dbg(&dev->udev->dev, 394 "%s : swap, read_buffer_length = %d\n", 395 __func__, dev->read_buffer_length); 396 tmp = dev->read_buffer_secondary; 397 dev->read_buffer_secondary = dev->read_buffer_primary; 398 dev->read_buffer_primary = tmp; 399 dev->secondary_head = 0; 400 dev->secondary_tail = dev->read_buffer_length; 401 dev->read_buffer_length = 0; 402 spin_unlock_irqrestore(&dev->buflock, flags); 403 /* we have a free buffer so use it */ 404 should_submit = 1; 405 } else { 406 /* even the primary was empty - we may need to do IO */ 407 if (!dev->read_urb_finished) { 408 /* somebody is doing IO */ 409 spin_unlock_irqrestore(&dev->buflock, flags); 410 dev_dbg(&dev->udev->dev, 411 "%s : submitted already\n", 412 __func__); 413 } else { 414 /* we must initiate input */ 415 dev_dbg(&dev->udev->dev, 416 "%s : initiate input\n", 417 __func__); 418 dev->read_urb_finished = 0; 419 spin_unlock_irqrestore(&dev->buflock, flags); 420 421 usb_fill_int_urb(dev->interrupt_in_urb, dev->udev, 422 usb_rcvintpipe(dev->udev, 423 dev->interrupt_in_endpoint->bEndpointAddress), 424 dev->interrupt_in_buffer, 425 usb_endpoint_maxp(dev->interrupt_in_endpoint), 426 adu_interrupt_in_callback, 427 dev, 428 dev->interrupt_in_endpoint->bInterval); 429 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 430 if (retval) { 431 dev->read_urb_finished = 1; 432 if (retval == -ENOMEM) { 433 retval = bytes_read ? bytes_read : -ENOMEM; 434 } 435 dev_dbg(&dev->udev->dev, 436 "%s : submit failed\n", 437 __func__); 438 goto exit; 439 } 440 } 441 442 /* we wait for I/O to complete */ 443 set_current_state(TASK_INTERRUPTIBLE); 444 add_wait_queue(&dev->read_wait, &wait); 445 spin_lock_irqsave(&dev->buflock, flags); 446 if (!dev->read_urb_finished) { 447 spin_unlock_irqrestore(&dev->buflock, flags); 448 timeout = schedule_timeout(COMMAND_TIMEOUT); 449 } else { 450 spin_unlock_irqrestore(&dev->buflock, flags); 451 set_current_state(TASK_RUNNING); 452 } 453 remove_wait_queue(&dev->read_wait, &wait); 454 455 if (timeout <= 0) { 456 dev_dbg(&dev->udev->dev, 457 "%s : timeout\n", __func__); 458 retval = bytes_read ? bytes_read : -ETIMEDOUT; 459 goto exit; 460 } 461 462 if (signal_pending(current)) { 463 dev_dbg(&dev->udev->dev, 464 "%s : signal pending\n", 465 __func__); 466 retval = bytes_read ? bytes_read : -EINTR; 467 goto exit; 468 } 469 } 470 } 471 } 472 473 retval = bytes_read; 474 /* if the primary buffer is empty then use it */ 475 spin_lock_irqsave(&dev->buflock, flags); 476 if (should_submit && dev->read_urb_finished) { 477 dev->read_urb_finished = 0; 478 spin_unlock_irqrestore(&dev->buflock, flags); 479 usb_fill_int_urb(dev->interrupt_in_urb, dev->udev, 480 usb_rcvintpipe(dev->udev, 481 dev->interrupt_in_endpoint->bEndpointAddress), 482 dev->interrupt_in_buffer, 483 usb_endpoint_maxp(dev->interrupt_in_endpoint), 484 adu_interrupt_in_callback, 485 dev, 486 dev->interrupt_in_endpoint->bInterval); 487 if (usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL) != 0) 488 dev->read_urb_finished = 1; 489 /* we ignore failure */ 490 } else { 491 spin_unlock_irqrestore(&dev->buflock, flags); 492 } 493 494 exit: 495 /* unlock the device */ 496 mutex_unlock(&dev->mtx); 497 498 return retval; 499 } 500 501 static ssize_t adu_write(struct file *file, const __user char *buffer, 502 size_t count, loff_t *ppos) 503 { 504 DECLARE_WAITQUEUE(waita, current); 505 struct adu_device *dev; 506 size_t bytes_written = 0; 507 size_t bytes_to_write; 508 size_t buffer_size; 509 unsigned long flags; 510 int retval; 511 512 dev = file->private_data; 513 514 retval = mutex_lock_interruptible(&dev->mtx); 515 if (retval) 516 goto exit_nolock; 517 518 /* verify that the device wasn't unplugged */ 519 if (dev->udev == NULL) { 520 retval = -ENODEV; 521 pr_err("No device or device unplugged %d\n", retval); 522 goto exit; 523 } 524 525 /* verify that we actually have some data to write */ 526 if (count == 0) { 527 dev_dbg(&dev->udev->dev, "%s : write request of 0 bytes\n", 528 __func__); 529 goto exit; 530 } 531 532 while (count > 0) { 533 add_wait_queue(&dev->write_wait, &waita); 534 set_current_state(TASK_INTERRUPTIBLE); 535 spin_lock_irqsave(&dev->buflock, flags); 536 if (!dev->out_urb_finished) { 537 spin_unlock_irqrestore(&dev->buflock, flags); 538 539 mutex_unlock(&dev->mtx); 540 if (signal_pending(current)) { 541 dev_dbg(&dev->udev->dev, "%s : interrupted\n", 542 __func__); 543 set_current_state(TASK_RUNNING); 544 retval = -EINTR; 545 goto exit_onqueue; 546 } 547 if (schedule_timeout(COMMAND_TIMEOUT) == 0) { 548 dev_dbg(&dev->udev->dev, 549 "%s - command timed out.\n", __func__); 550 retval = -ETIMEDOUT; 551 goto exit_onqueue; 552 } 553 remove_wait_queue(&dev->write_wait, &waita); 554 retval = mutex_lock_interruptible(&dev->mtx); 555 if (retval) { 556 retval = bytes_written ? bytes_written : retval; 557 goto exit_nolock; 558 } 559 560 dev_dbg(&dev->udev->dev, 561 "%s : in progress, count = %zd\n", 562 __func__, count); 563 } else { 564 spin_unlock_irqrestore(&dev->buflock, flags); 565 set_current_state(TASK_RUNNING); 566 remove_wait_queue(&dev->write_wait, &waita); 567 dev_dbg(&dev->udev->dev, "%s : sending, count = %zd\n", 568 __func__, count); 569 570 /* write the data into interrupt_out_buffer from userspace */ 571 buffer_size = usb_endpoint_maxp(dev->interrupt_out_endpoint); 572 bytes_to_write = count > buffer_size ? buffer_size : count; 573 dev_dbg(&dev->udev->dev, 574 "%s : buffer_size = %zd, count = %zd, bytes_to_write = %zd\n", 575 __func__, buffer_size, count, bytes_to_write); 576 577 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write) != 0) { 578 retval = -EFAULT; 579 goto exit; 580 } 581 582 /* send off the urb */ 583 usb_fill_int_urb( 584 dev->interrupt_out_urb, 585 dev->udev, 586 usb_sndintpipe(dev->udev, dev->interrupt_out_endpoint->bEndpointAddress), 587 dev->interrupt_out_buffer, 588 bytes_to_write, 589 adu_interrupt_out_callback, 590 dev, 591 dev->interrupt_out_endpoint->bInterval); 592 dev->interrupt_out_urb->actual_length = bytes_to_write; 593 dev->out_urb_finished = 0; 594 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL); 595 if (retval < 0) { 596 dev->out_urb_finished = 1; 597 dev_err(&dev->udev->dev, "Couldn't submit " 598 "interrupt_out_urb %d\n", retval); 599 goto exit; 600 } 601 602 buffer += bytes_to_write; 603 count -= bytes_to_write; 604 605 bytes_written += bytes_to_write; 606 } 607 } 608 mutex_unlock(&dev->mtx); 609 return bytes_written; 610 611 exit: 612 mutex_unlock(&dev->mtx); 613 exit_nolock: 614 return retval; 615 616 exit_onqueue: 617 remove_wait_queue(&dev->write_wait, &waita); 618 return retval; 619 } 620 621 /* file operations needed when we register this driver */ 622 static const struct file_operations adu_fops = { 623 .owner = THIS_MODULE, 624 .read = adu_read, 625 .write = adu_write, 626 .open = adu_open, 627 .release = adu_release, 628 .llseek = noop_llseek, 629 }; 630 631 /* 632 * usb class driver info in order to get a minor number from the usb core, 633 * and to have the device registered with devfs and the driver core 634 */ 635 static struct usb_class_driver adu_class = { 636 .name = "usb/adutux%d", 637 .fops = &adu_fops, 638 .minor_base = ADU_MINOR_BASE, 639 }; 640 641 /** 642 * adu_probe 643 * 644 * Called by the usb core when a new device is connected that it thinks 645 * this driver might be interested in. 646 */ 647 static int adu_probe(struct usb_interface *interface, 648 const struct usb_device_id *id) 649 { 650 struct usb_device *udev = interface_to_usbdev(interface); 651 struct adu_device *dev = NULL; 652 int retval = -ENOMEM; 653 int in_end_size; 654 int out_end_size; 655 int res; 656 657 /* allocate memory for our device state and initialize it */ 658 dev = kzalloc(sizeof(struct adu_device), GFP_KERNEL); 659 if (!dev) 660 return -ENOMEM; 661 662 mutex_init(&dev->mtx); 663 spin_lock_init(&dev->buflock); 664 dev->udev = udev; 665 init_waitqueue_head(&dev->read_wait); 666 init_waitqueue_head(&dev->write_wait); 667 668 res = usb_find_common_endpoints_reverse(&interface->altsetting[0], 669 NULL, NULL, 670 &dev->interrupt_in_endpoint, 671 &dev->interrupt_out_endpoint); 672 if (res) { 673 dev_err(&interface->dev, "interrupt endpoints not found\n"); 674 retval = res; 675 goto error; 676 } 677 678 in_end_size = usb_endpoint_maxp(dev->interrupt_in_endpoint); 679 out_end_size = usb_endpoint_maxp(dev->interrupt_out_endpoint); 680 681 dev->read_buffer_primary = kmalloc((4 * in_end_size), GFP_KERNEL); 682 if (!dev->read_buffer_primary) 683 goto error; 684 685 /* debug code prime the buffer */ 686 memset(dev->read_buffer_primary, 'a', in_end_size); 687 memset(dev->read_buffer_primary + in_end_size, 'b', in_end_size); 688 memset(dev->read_buffer_primary + (2 * in_end_size), 'c', in_end_size); 689 memset(dev->read_buffer_primary + (3 * in_end_size), 'd', in_end_size); 690 691 dev->read_buffer_secondary = kmalloc((4 * in_end_size), GFP_KERNEL); 692 if (!dev->read_buffer_secondary) 693 goto error; 694 695 /* debug code prime the buffer */ 696 memset(dev->read_buffer_secondary, 'e', in_end_size); 697 memset(dev->read_buffer_secondary + in_end_size, 'f', in_end_size); 698 memset(dev->read_buffer_secondary + (2 * in_end_size), 'g', in_end_size); 699 memset(dev->read_buffer_secondary + (3 * in_end_size), 'h', in_end_size); 700 701 dev->interrupt_in_buffer = kmalloc(in_end_size, GFP_KERNEL); 702 if (!dev->interrupt_in_buffer) 703 goto error; 704 705 /* debug code prime the buffer */ 706 memset(dev->interrupt_in_buffer, 'i', in_end_size); 707 708 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL); 709 if (!dev->interrupt_in_urb) 710 goto error; 711 dev->interrupt_out_buffer = kmalloc(out_end_size, GFP_KERNEL); 712 if (!dev->interrupt_out_buffer) 713 goto error; 714 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL); 715 if (!dev->interrupt_out_urb) 716 goto error; 717 718 if (!usb_string(udev, udev->descriptor.iSerialNumber, dev->serial_number, 719 sizeof(dev->serial_number))) { 720 dev_err(&interface->dev, "Could not retrieve serial number\n"); 721 retval = -EIO; 722 goto error; 723 } 724 dev_dbg(&interface->dev,"serial_number=%s", dev->serial_number); 725 726 /* we can register the device now, as it is ready */ 727 usb_set_intfdata(interface, dev); 728 729 retval = usb_register_dev(interface, &adu_class); 730 731 if (retval) { 732 /* something prevented us from registering this driver */ 733 dev_err(&interface->dev, "Not able to get a minor for this device.\n"); 734 usb_set_intfdata(interface, NULL); 735 goto error; 736 } 737 738 dev->minor = interface->minor; 739 740 /* let the user know what node this device is now attached to */ 741 dev_info(&interface->dev, "ADU%d %s now attached to /dev/usb/adutux%d\n", 742 le16_to_cpu(udev->descriptor.idProduct), dev->serial_number, 743 (dev->minor - ADU_MINOR_BASE)); 744 745 return 0; 746 747 error: 748 adu_delete(dev); 749 return retval; 750 } 751 752 /** 753 * adu_disconnect 754 * 755 * Called by the usb core when the device is removed from the system. 756 */ 757 static void adu_disconnect(struct usb_interface *interface) 758 { 759 struct adu_device *dev; 760 761 dev = usb_get_intfdata(interface); 762 763 mutex_lock(&dev->mtx); /* not interruptible */ 764 dev->udev = NULL; /* poison */ 765 usb_deregister_dev(interface, &adu_class); 766 mutex_unlock(&dev->mtx); 767 768 mutex_lock(&adutux_mutex); 769 usb_set_intfdata(interface, NULL); 770 771 /* if the device is not opened, then we clean up right now */ 772 if (!dev->open_count) 773 adu_delete(dev); 774 775 mutex_unlock(&adutux_mutex); 776 } 777 778 /* usb specific object needed to register this driver with the usb subsystem */ 779 static struct usb_driver adu_driver = { 780 .name = "adutux", 781 .probe = adu_probe, 782 .disconnect = adu_disconnect, 783 .id_table = device_table, 784 }; 785 786 module_usb_driver(adu_driver); 787 788 MODULE_AUTHOR(DRIVER_AUTHOR); 789 MODULE_DESCRIPTION(DRIVER_DESC); 790 MODULE_LICENSE("GPL"); 791