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; 158 159 adu_debug_data(&dev->udev->dev, __func__, 160 urb->actual_length, urb->transfer_buffer); 161 162 spin_lock(&dev->buflock); 163 164 if (status != 0) { 165 if ((status != -ENOENT) && (status != -ECONNRESET) && 166 (status != -ESHUTDOWN)) { 167 dev_dbg(&dev->udev->dev, 168 "%s : nonzero status received: %d\n", 169 __func__, status); 170 } 171 goto exit; 172 } 173 174 if (urb->actual_length > 0 && dev->interrupt_in_buffer[0] != 0x00) { 175 if (dev->read_buffer_length < 176 (4 * usb_endpoint_maxp(dev->interrupt_in_endpoint)) - 177 (urb->actual_length)) { 178 memcpy (dev->read_buffer_primary + 179 dev->read_buffer_length, 180 dev->interrupt_in_buffer, urb->actual_length); 181 182 dev->read_buffer_length += urb->actual_length; 183 dev_dbg(&dev->udev->dev,"%s reading %d\n", __func__, 184 urb->actual_length); 185 } else { 186 dev_dbg(&dev->udev->dev,"%s : read_buffer overflow\n", 187 __func__); 188 } 189 } 190 191 exit: 192 dev->read_urb_finished = 1; 193 spin_unlock(&dev->buflock); 194 /* always wake up so we recover from errors */ 195 wake_up_interruptible(&dev->read_wait); 196 } 197 198 static void adu_interrupt_out_callback(struct urb *urb) 199 { 200 struct adu_device *dev = urb->context; 201 int status = urb->status; 202 203 adu_debug_data(&dev->udev->dev, __func__, 204 urb->actual_length, urb->transfer_buffer); 205 206 if (status != 0) { 207 if ((status != -ENOENT) && 208 (status != -ECONNRESET)) { 209 dev_dbg(&dev->udev->dev, 210 "%s :nonzero status received: %d\n", __func__, 211 status); 212 } 213 return; 214 } 215 216 spin_lock(&dev->buflock); 217 dev->out_urb_finished = 1; 218 wake_up(&dev->write_wait); 219 spin_unlock(&dev->buflock); 220 } 221 222 static int adu_open(struct inode *inode, struct file *file) 223 { 224 struct adu_device *dev = NULL; 225 struct usb_interface *interface; 226 int subminor; 227 int retval; 228 229 subminor = iminor(inode); 230 231 retval = mutex_lock_interruptible(&adutux_mutex); 232 if (retval) 233 goto exit_no_lock; 234 235 interface = usb_find_interface(&adu_driver, subminor); 236 if (!interface) { 237 pr_err("%s - error, can't find device for minor %d\n", 238 __func__, subminor); 239 retval = -ENODEV; 240 goto exit_no_device; 241 } 242 243 dev = usb_get_intfdata(interface); 244 if (!dev || !dev->udev) { 245 retval = -ENODEV; 246 goto exit_no_device; 247 } 248 249 /* check that nobody else is using the device */ 250 if (dev->open_count) { 251 retval = -EBUSY; 252 goto exit_no_device; 253 } 254 255 ++dev->open_count; 256 dev_dbg(&dev->udev->dev, "%s: open count %d\n", __func__, 257 dev->open_count); 258 259 /* save device in the file's private structure */ 260 file->private_data = dev; 261 262 /* initialize in direction */ 263 dev->read_buffer_length = 0; 264 265 /* fixup first read by having urb waiting for it */ 266 usb_fill_int_urb(dev->interrupt_in_urb, dev->udev, 267 usb_rcvintpipe(dev->udev, 268 dev->interrupt_in_endpoint->bEndpointAddress), 269 dev->interrupt_in_buffer, 270 usb_endpoint_maxp(dev->interrupt_in_endpoint), 271 adu_interrupt_in_callback, dev, 272 dev->interrupt_in_endpoint->bInterval); 273 dev->read_urb_finished = 0; 274 if (usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL)) 275 dev->read_urb_finished = 1; 276 /* we ignore failure */ 277 /* end of fixup for first read */ 278 279 /* initialize out direction */ 280 dev->out_urb_finished = 1; 281 282 retval = 0; 283 284 exit_no_device: 285 mutex_unlock(&adutux_mutex); 286 exit_no_lock: 287 return retval; 288 } 289 290 static void adu_release_internal(struct adu_device *dev) 291 { 292 /* decrement our usage count for the device */ 293 --dev->open_count; 294 dev_dbg(&dev->udev->dev, "%s : open count %d\n", __func__, 295 dev->open_count); 296 if (dev->open_count <= 0) { 297 adu_abort_transfers(dev); 298 dev->open_count = 0; 299 } 300 } 301 302 static int adu_release(struct inode *inode, struct file *file) 303 { 304 struct adu_device *dev; 305 int retval = 0; 306 307 if (file == NULL) { 308 retval = -ENODEV; 309 goto exit; 310 } 311 312 dev = file->private_data; 313 if (dev == NULL) { 314 retval = -ENODEV; 315 goto exit; 316 } 317 318 mutex_lock(&adutux_mutex); /* not interruptible */ 319 320 if (dev->open_count <= 0) { 321 dev_dbg(&dev->udev->dev, "%s : device not opened\n", __func__); 322 retval = -ENODEV; 323 goto unlock; 324 } 325 326 adu_release_internal(dev); 327 if (dev->udev == NULL) { 328 /* the device was unplugged before the file was released */ 329 if (!dev->open_count) /* ... and we're the last user */ 330 adu_delete(dev); 331 } 332 unlock: 333 mutex_unlock(&adutux_mutex); 334 exit: 335 return retval; 336 } 337 338 static ssize_t adu_read(struct file *file, __user char *buffer, size_t count, 339 loff_t *ppos) 340 { 341 struct adu_device *dev; 342 size_t bytes_read = 0; 343 size_t bytes_to_read = count; 344 int i; 345 int retval = 0; 346 int timeout = 0; 347 int should_submit = 0; 348 unsigned long flags; 349 DECLARE_WAITQUEUE(wait, current); 350 351 dev = file->private_data; 352 if (mutex_lock_interruptible(&dev->mtx)) 353 return -ERESTARTSYS; 354 355 /* verify that the device wasn't unplugged */ 356 if (dev->udev == NULL) { 357 retval = -ENODEV; 358 pr_err("No device or device unplugged %d\n", retval); 359 goto exit; 360 } 361 362 /* verify that some data was requested */ 363 if (count == 0) { 364 dev_dbg(&dev->udev->dev, "%s : read request of 0 bytes\n", 365 __func__); 366 goto exit; 367 } 368 369 timeout = COMMAND_TIMEOUT; 370 dev_dbg(&dev->udev->dev, "%s : about to start looping\n", __func__); 371 while (bytes_to_read) { 372 int data_in_secondary = dev->secondary_tail - dev->secondary_head; 373 dev_dbg(&dev->udev->dev, 374 "%s : while, data_in_secondary=%d, status=%d\n", 375 __func__, data_in_secondary, 376 dev->interrupt_in_urb->status); 377 378 if (data_in_secondary) { 379 /* drain secondary buffer */ 380 int amount = bytes_to_read < data_in_secondary ? bytes_to_read : data_in_secondary; 381 i = copy_to_user(buffer, dev->read_buffer_secondary+dev->secondary_head, amount); 382 if (i) { 383 retval = -EFAULT; 384 goto exit; 385 } 386 dev->secondary_head += (amount - i); 387 bytes_read += (amount - i); 388 bytes_to_read -= (amount - i); 389 } else { 390 /* we check the primary buffer */ 391 spin_lock_irqsave (&dev->buflock, flags); 392 if (dev->read_buffer_length) { 393 /* we secure access to the primary */ 394 char *tmp; 395 dev_dbg(&dev->udev->dev, 396 "%s : swap, read_buffer_length = %d\n", 397 __func__, dev->read_buffer_length); 398 tmp = dev->read_buffer_secondary; 399 dev->read_buffer_secondary = dev->read_buffer_primary; 400 dev->read_buffer_primary = tmp; 401 dev->secondary_head = 0; 402 dev->secondary_tail = dev->read_buffer_length; 403 dev->read_buffer_length = 0; 404 spin_unlock_irqrestore(&dev->buflock, flags); 405 /* we have a free buffer so use it */ 406 should_submit = 1; 407 } else { 408 /* even the primary was empty - we may need to do IO */ 409 if (!dev->read_urb_finished) { 410 /* somebody is doing IO */ 411 spin_unlock_irqrestore(&dev->buflock, flags); 412 dev_dbg(&dev->udev->dev, 413 "%s : submitted already\n", 414 __func__); 415 } else { 416 /* we must initiate input */ 417 dev_dbg(&dev->udev->dev, 418 "%s : initiate input\n", 419 __func__); 420 dev->read_urb_finished = 0; 421 spin_unlock_irqrestore(&dev->buflock, flags); 422 423 usb_fill_int_urb(dev->interrupt_in_urb, dev->udev, 424 usb_rcvintpipe(dev->udev, 425 dev->interrupt_in_endpoint->bEndpointAddress), 426 dev->interrupt_in_buffer, 427 usb_endpoint_maxp(dev->interrupt_in_endpoint), 428 adu_interrupt_in_callback, 429 dev, 430 dev->interrupt_in_endpoint->bInterval); 431 retval = usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL); 432 if (retval) { 433 dev->read_urb_finished = 1; 434 if (retval == -ENOMEM) { 435 retval = bytes_read ? bytes_read : -ENOMEM; 436 } 437 dev_dbg(&dev->udev->dev, 438 "%s : submit failed\n", 439 __func__); 440 goto exit; 441 } 442 } 443 444 /* we wait for I/O to complete */ 445 set_current_state(TASK_INTERRUPTIBLE); 446 add_wait_queue(&dev->read_wait, &wait); 447 spin_lock_irqsave(&dev->buflock, flags); 448 if (!dev->read_urb_finished) { 449 spin_unlock_irqrestore(&dev->buflock, flags); 450 timeout = schedule_timeout(COMMAND_TIMEOUT); 451 } else { 452 spin_unlock_irqrestore(&dev->buflock, flags); 453 set_current_state(TASK_RUNNING); 454 } 455 remove_wait_queue(&dev->read_wait, &wait); 456 457 if (timeout <= 0) { 458 dev_dbg(&dev->udev->dev, 459 "%s : timeout\n", __func__); 460 retval = bytes_read ? bytes_read : -ETIMEDOUT; 461 goto exit; 462 } 463 464 if (signal_pending(current)) { 465 dev_dbg(&dev->udev->dev, 466 "%s : signal pending\n", 467 __func__); 468 retval = bytes_read ? bytes_read : -EINTR; 469 goto exit; 470 } 471 } 472 } 473 } 474 475 retval = bytes_read; 476 /* if the primary buffer is empty then use it */ 477 spin_lock_irqsave(&dev->buflock, flags); 478 if (should_submit && dev->read_urb_finished) { 479 dev->read_urb_finished = 0; 480 spin_unlock_irqrestore(&dev->buflock, flags); 481 usb_fill_int_urb(dev->interrupt_in_urb, dev->udev, 482 usb_rcvintpipe(dev->udev, 483 dev->interrupt_in_endpoint->bEndpointAddress), 484 dev->interrupt_in_buffer, 485 usb_endpoint_maxp(dev->interrupt_in_endpoint), 486 adu_interrupt_in_callback, 487 dev, 488 dev->interrupt_in_endpoint->bInterval); 489 if (usb_submit_urb(dev->interrupt_in_urb, GFP_KERNEL) != 0) 490 dev->read_urb_finished = 1; 491 /* we ignore failure */ 492 } else { 493 spin_unlock_irqrestore(&dev->buflock, flags); 494 } 495 496 exit: 497 /* unlock the device */ 498 mutex_unlock(&dev->mtx); 499 500 return retval; 501 } 502 503 static ssize_t adu_write(struct file *file, const __user char *buffer, 504 size_t count, loff_t *ppos) 505 { 506 DECLARE_WAITQUEUE(waita, current); 507 struct adu_device *dev; 508 size_t bytes_written = 0; 509 size_t bytes_to_write; 510 size_t buffer_size; 511 unsigned long flags; 512 int retval; 513 514 dev = file->private_data; 515 516 retval = mutex_lock_interruptible(&dev->mtx); 517 if (retval) 518 goto exit_nolock; 519 520 /* verify that the device wasn't unplugged */ 521 if (dev->udev == NULL) { 522 retval = -ENODEV; 523 pr_err("No device or device unplugged %d\n", retval); 524 goto exit; 525 } 526 527 /* verify that we actually have some data to write */ 528 if (count == 0) { 529 dev_dbg(&dev->udev->dev, "%s : write request of 0 bytes\n", 530 __func__); 531 goto exit; 532 } 533 534 while (count > 0) { 535 add_wait_queue(&dev->write_wait, &waita); 536 set_current_state(TASK_INTERRUPTIBLE); 537 spin_lock_irqsave(&dev->buflock, flags); 538 if (!dev->out_urb_finished) { 539 spin_unlock_irqrestore(&dev->buflock, flags); 540 541 mutex_unlock(&dev->mtx); 542 if (signal_pending(current)) { 543 dev_dbg(&dev->udev->dev, "%s : interrupted\n", 544 __func__); 545 set_current_state(TASK_RUNNING); 546 retval = -EINTR; 547 goto exit_onqueue; 548 } 549 if (schedule_timeout(COMMAND_TIMEOUT) == 0) { 550 dev_dbg(&dev->udev->dev, 551 "%s - command timed out.\n", __func__); 552 retval = -ETIMEDOUT; 553 goto exit_onqueue; 554 } 555 remove_wait_queue(&dev->write_wait, &waita); 556 retval = mutex_lock_interruptible(&dev->mtx); 557 if (retval) { 558 retval = bytes_written ? bytes_written : retval; 559 goto exit_nolock; 560 } 561 562 dev_dbg(&dev->udev->dev, 563 "%s : in progress, count = %zd\n", 564 __func__, count); 565 } else { 566 spin_unlock_irqrestore(&dev->buflock, flags); 567 set_current_state(TASK_RUNNING); 568 remove_wait_queue(&dev->write_wait, &waita); 569 dev_dbg(&dev->udev->dev, "%s : sending, count = %zd\n", 570 __func__, count); 571 572 /* write the data into interrupt_out_buffer from userspace */ 573 buffer_size = usb_endpoint_maxp(dev->interrupt_out_endpoint); 574 bytes_to_write = count > buffer_size ? buffer_size : count; 575 dev_dbg(&dev->udev->dev, 576 "%s : buffer_size = %zd, count = %zd, bytes_to_write = %zd\n", 577 __func__, buffer_size, count, bytes_to_write); 578 579 if (copy_from_user(dev->interrupt_out_buffer, buffer, bytes_to_write) != 0) { 580 retval = -EFAULT; 581 goto exit; 582 } 583 584 /* send off the urb */ 585 usb_fill_int_urb( 586 dev->interrupt_out_urb, 587 dev->udev, 588 usb_sndintpipe(dev->udev, dev->interrupt_out_endpoint->bEndpointAddress), 589 dev->interrupt_out_buffer, 590 bytes_to_write, 591 adu_interrupt_out_callback, 592 dev, 593 dev->interrupt_out_endpoint->bInterval); 594 dev->interrupt_out_urb->actual_length = bytes_to_write; 595 dev->out_urb_finished = 0; 596 retval = usb_submit_urb(dev->interrupt_out_urb, GFP_KERNEL); 597 if (retval < 0) { 598 dev->out_urb_finished = 1; 599 dev_err(&dev->udev->dev, "Couldn't submit " 600 "interrupt_out_urb %d\n", retval); 601 goto exit; 602 } 603 604 buffer += bytes_to_write; 605 count -= bytes_to_write; 606 607 bytes_written += bytes_to_write; 608 } 609 } 610 mutex_unlock(&dev->mtx); 611 return bytes_written; 612 613 exit: 614 mutex_unlock(&dev->mtx); 615 exit_nolock: 616 return retval; 617 618 exit_onqueue: 619 remove_wait_queue(&dev->write_wait, &waita); 620 return retval; 621 } 622 623 /* file operations needed when we register this driver */ 624 static const struct file_operations adu_fops = { 625 .owner = THIS_MODULE, 626 .read = adu_read, 627 .write = adu_write, 628 .open = adu_open, 629 .release = adu_release, 630 .llseek = noop_llseek, 631 }; 632 633 /* 634 * usb class driver info in order to get a minor number from the usb core, 635 * and to have the device registered with devfs and the driver core 636 */ 637 static struct usb_class_driver adu_class = { 638 .name = "usb/adutux%d", 639 .fops = &adu_fops, 640 .minor_base = ADU_MINOR_BASE, 641 }; 642 643 /** 644 * adu_probe 645 * 646 * Called by the usb core when a new device is connected that it thinks 647 * this driver might be interested in. 648 */ 649 static int adu_probe(struct usb_interface *interface, 650 const struct usb_device_id *id) 651 { 652 struct usb_device *udev = interface_to_usbdev(interface); 653 struct adu_device *dev = NULL; 654 int retval = -ENOMEM; 655 int in_end_size; 656 int out_end_size; 657 int res; 658 659 /* allocate memory for our device state and initialize it */ 660 dev = kzalloc(sizeof(struct adu_device), GFP_KERNEL); 661 if (!dev) 662 return -ENOMEM; 663 664 mutex_init(&dev->mtx); 665 spin_lock_init(&dev->buflock); 666 dev->udev = udev; 667 init_waitqueue_head(&dev->read_wait); 668 init_waitqueue_head(&dev->write_wait); 669 670 res = usb_find_common_endpoints_reverse(&interface->altsetting[0], 671 NULL, NULL, 672 &dev->interrupt_in_endpoint, 673 &dev->interrupt_out_endpoint); 674 if (res) { 675 dev_err(&interface->dev, "interrupt endpoints not found\n"); 676 retval = res; 677 goto error; 678 } 679 680 in_end_size = usb_endpoint_maxp(dev->interrupt_in_endpoint); 681 out_end_size = usb_endpoint_maxp(dev->interrupt_out_endpoint); 682 683 dev->read_buffer_primary = kmalloc((4 * in_end_size), GFP_KERNEL); 684 if (!dev->read_buffer_primary) 685 goto error; 686 687 /* debug code prime the buffer */ 688 memset(dev->read_buffer_primary, 'a', in_end_size); 689 memset(dev->read_buffer_primary + in_end_size, 'b', in_end_size); 690 memset(dev->read_buffer_primary + (2 * in_end_size), 'c', in_end_size); 691 memset(dev->read_buffer_primary + (3 * in_end_size), 'd', in_end_size); 692 693 dev->read_buffer_secondary = kmalloc((4 * in_end_size), GFP_KERNEL); 694 if (!dev->read_buffer_secondary) 695 goto error; 696 697 /* debug code prime the buffer */ 698 memset(dev->read_buffer_secondary, 'e', in_end_size); 699 memset(dev->read_buffer_secondary + in_end_size, 'f', in_end_size); 700 memset(dev->read_buffer_secondary + (2 * in_end_size), 'g', in_end_size); 701 memset(dev->read_buffer_secondary + (3 * in_end_size), 'h', in_end_size); 702 703 dev->interrupt_in_buffer = kmalloc(in_end_size, GFP_KERNEL); 704 if (!dev->interrupt_in_buffer) 705 goto error; 706 707 /* debug code prime the buffer */ 708 memset(dev->interrupt_in_buffer, 'i', in_end_size); 709 710 dev->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL); 711 if (!dev->interrupt_in_urb) 712 goto error; 713 dev->interrupt_out_buffer = kmalloc(out_end_size, GFP_KERNEL); 714 if (!dev->interrupt_out_buffer) 715 goto error; 716 dev->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL); 717 if (!dev->interrupt_out_urb) 718 goto error; 719 720 if (!usb_string(udev, udev->descriptor.iSerialNumber, dev->serial_number, 721 sizeof(dev->serial_number))) { 722 dev_err(&interface->dev, "Could not retrieve serial number\n"); 723 retval = -EIO; 724 goto error; 725 } 726 dev_dbg(&interface->dev,"serial_number=%s", dev->serial_number); 727 728 /* we can register the device now, as it is ready */ 729 usb_set_intfdata(interface, dev); 730 731 retval = usb_register_dev(interface, &adu_class); 732 733 if (retval) { 734 /* something prevented us from registering this driver */ 735 dev_err(&interface->dev, "Not able to get a minor for this device.\n"); 736 usb_set_intfdata(interface, NULL); 737 goto error; 738 } 739 740 dev->minor = interface->minor; 741 742 /* let the user know what node this device is now attached to */ 743 dev_info(&interface->dev, "ADU%d %s now attached to /dev/usb/adutux%d\n", 744 le16_to_cpu(udev->descriptor.idProduct), dev->serial_number, 745 (dev->minor - ADU_MINOR_BASE)); 746 747 return 0; 748 749 error: 750 adu_delete(dev); 751 return retval; 752 } 753 754 /** 755 * adu_disconnect 756 * 757 * Called by the usb core when the device is removed from the system. 758 */ 759 static void adu_disconnect(struct usb_interface *interface) 760 { 761 struct adu_device *dev; 762 763 dev = usb_get_intfdata(interface); 764 765 mutex_lock(&dev->mtx); /* not interruptible */ 766 dev->udev = NULL; /* poison */ 767 usb_deregister_dev(interface, &adu_class); 768 mutex_unlock(&dev->mtx); 769 770 mutex_lock(&adutux_mutex); 771 usb_set_intfdata(interface, NULL); 772 773 /* if the device is not opened, then we clean up right now */ 774 if (!dev->open_count) 775 adu_delete(dev); 776 777 mutex_unlock(&adutux_mutex); 778 } 779 780 /* usb specific object needed to register this driver with the usb subsystem */ 781 static struct usb_driver adu_driver = { 782 .name = "adutux", 783 .probe = adu_probe, 784 .disconnect = adu_disconnect, 785 .id_table = device_table, 786 }; 787 788 module_usb_driver(adu_driver); 789 790 MODULE_AUTHOR(DRIVER_AUTHOR); 791 MODULE_DESCRIPTION(DRIVER_DESC); 792 MODULE_LICENSE("GPL"); 793