1 /* 2 * Berkshire USB-PC Watchdog Card Driver 3 * 4 * (c) Copyright 2004-2007 Wim Van Sebroeck <wim@iguana.be>. 5 * 6 * Based on source code of the following authors: 7 * Ken Hollis <kenji@bitgate.com>, 8 * Alan Cox <alan@lxorguk.ukuu.org.uk>, 9 * Matt Domsch <Matt_Domsch@dell.com>, 10 * Rob Radez <rob@osinvestor.com>, 11 * Greg Kroah-Hartman <greg@kroah.com> 12 * 13 * This program is free software; you can redistribute it and/or 14 * modify it under the terms of the GNU General Public License 15 * as published by the Free Software Foundation; either version 16 * 2 of the License, or (at your option) any later version. 17 * 18 * Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor 19 * provide warranty for any of this software. This material is 20 * provided "AS-IS" and at no charge. 21 * 22 * Thanks also to Simon Machell at Berkshire Products Inc. for 23 * providing the test hardware. More info is available at 24 * http://www.berkprod.com/ or http://www.pcwatchdog.com/ 25 */ 26 27 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 28 29 #include <linux/module.h> /* For module specific items */ 30 #include <linux/moduleparam.h> /* For new moduleparam's */ 31 #include <linux/types.h> /* For standard types (like size_t) */ 32 #include <linux/errno.h> /* For the -ENODEV/... values */ 33 #include <linux/kernel.h> /* For printk/panic/... */ 34 #include <linux/delay.h> /* For mdelay function */ 35 #include <linux/miscdevice.h> /* For struct miscdevice */ 36 #include <linux/watchdog.h> /* For the watchdog specific items */ 37 #include <linux/notifier.h> /* For notifier support */ 38 #include <linux/reboot.h> /* For reboot_notifier stuff */ 39 #include <linux/init.h> /* For __init/__exit/... */ 40 #include <linux/fs.h> /* For file operations */ 41 #include <linux/usb.h> /* For USB functions */ 42 #include <linux/slab.h> /* For kmalloc, ... */ 43 #include <linux/mutex.h> /* For mutex locking */ 44 #include <linux/hid.h> /* For HID_REQ_SET_REPORT & HID_DT_REPORT */ 45 #include <linux/uaccess.h> /* For copy_to_user/put_user/... */ 46 47 48 /* Module and Version Information */ 49 #define DRIVER_VERSION "1.02" 50 #define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>" 51 #define DRIVER_DESC "Berkshire USB-PC Watchdog driver" 52 #define DRIVER_NAME "pcwd_usb" 53 54 MODULE_AUTHOR(DRIVER_AUTHOR); 55 MODULE_DESCRIPTION(DRIVER_DESC); 56 MODULE_LICENSE("GPL"); 57 58 #define WATCHDOG_HEARTBEAT 0 /* default heartbeat = 59 delay-time from dip-switches */ 60 static int heartbeat = WATCHDOG_HEARTBEAT; 61 module_param(heartbeat, int, 0); 62 MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. " 63 "(0<heartbeat<65536 or 0=delay-time from dip-switches, default=" 64 __MODULE_STRING(WATCHDOG_HEARTBEAT) ")"); 65 66 static bool nowayout = WATCHDOG_NOWAYOUT; 67 module_param(nowayout, bool, 0); 68 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" 69 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); 70 71 /* The vendor and product id's for the USB-PC Watchdog card */ 72 #define USB_PCWD_VENDOR_ID 0x0c98 73 #define USB_PCWD_PRODUCT_ID 0x1140 74 75 /* table of devices that work with this driver */ 76 static const struct usb_device_id usb_pcwd_table[] = { 77 { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) }, 78 { } /* Terminating entry */ 79 }; 80 MODULE_DEVICE_TABLE(usb, usb_pcwd_table); 81 82 /* according to documentation max. time to process a command for the USB 83 * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */ 84 #define USB_COMMAND_TIMEOUT 250 85 86 /* Watchdog's internal commands */ 87 #define CMD_READ_TEMP 0x02 /* Read Temperature; 88 Re-trigger Watchdog */ 89 #define CMD_TRIGGER CMD_READ_TEMP 90 #define CMD_GET_STATUS 0x04 /* Get Status Information */ 91 #define CMD_GET_FIRMWARE_VERSION 0x08 /* Get Firmware Version */ 92 #define CMD_GET_DIP_SWITCH_SETTINGS 0x0c /* Get Dip Switch Settings */ 93 #define CMD_READ_WATCHDOG_TIMEOUT 0x18 /* Read Current Watchdog Time */ 94 #define CMD_WRITE_WATCHDOG_TIMEOUT 0x19 /* Write Current WatchdogTime */ 95 #define CMD_ENABLE_WATCHDOG 0x30 /* Enable / Disable Watchdog */ 96 #define CMD_DISABLE_WATCHDOG CMD_ENABLE_WATCHDOG 97 98 /* Watchdog's Dip Switch heartbeat values */ 99 static const int heartbeat_tbl[] = { 100 5, /* OFF-OFF-OFF = 5 Sec */ 101 10, /* OFF-OFF-ON = 10 Sec */ 102 30, /* OFF-ON-OFF = 30 Sec */ 103 60, /* OFF-ON-ON = 1 Min */ 104 300, /* ON-OFF-OFF = 5 Min */ 105 600, /* ON-OFF-ON = 10 Min */ 106 1800, /* ON-ON-OFF = 30 Min */ 107 3600, /* ON-ON-ON = 1 hour */ 108 }; 109 110 /* We can only use 1 card due to the /dev/watchdog restriction */ 111 static int cards_found; 112 113 /* some internal variables */ 114 static unsigned long is_active; 115 static char expect_release; 116 117 /* Structure to hold all of our device specific stuff */ 118 struct usb_pcwd_private { 119 /* save off the usb device pointer */ 120 struct usb_device *udev; 121 /* the interface for this device */ 122 struct usb_interface *interface; 123 124 /* the interface number used for cmd's */ 125 unsigned int interface_number; 126 127 /* the buffer to intr data */ 128 unsigned char *intr_buffer; 129 /* the dma address for the intr buffer */ 130 dma_addr_t intr_dma; 131 /* the size of the intr buffer */ 132 size_t intr_size; 133 /* the urb used for the intr pipe */ 134 struct urb *intr_urb; 135 136 /* The command that is reported back */ 137 unsigned char cmd_command; 138 /* The data MSB that is reported back */ 139 unsigned char cmd_data_msb; 140 /* The data LSB that is reported back */ 141 unsigned char cmd_data_lsb; 142 /* true if we received a report after a command */ 143 atomic_t cmd_received; 144 145 /* Wether or not the device exists */ 146 int exists; 147 /* locks this structure */ 148 struct mutex mtx; 149 }; 150 static struct usb_pcwd_private *usb_pcwd_device; 151 152 /* prevent races between open() and disconnect() */ 153 static DEFINE_MUTEX(disconnect_mutex); 154 155 /* local function prototypes */ 156 static int usb_pcwd_probe(struct usb_interface *interface, 157 const struct usb_device_id *id); 158 static void usb_pcwd_disconnect(struct usb_interface *interface); 159 160 /* usb specific object needed to register this driver with the usb subsystem */ 161 static struct usb_driver usb_pcwd_driver = { 162 .name = DRIVER_NAME, 163 .probe = usb_pcwd_probe, 164 .disconnect = usb_pcwd_disconnect, 165 .id_table = usb_pcwd_table, 166 }; 167 168 169 static void usb_pcwd_intr_done(struct urb *urb) 170 { 171 struct usb_pcwd_private *usb_pcwd = 172 (struct usb_pcwd_private *)urb->context; 173 unsigned char *data = usb_pcwd->intr_buffer; 174 struct device *dev = &usb_pcwd->interface->dev; 175 int retval; 176 177 switch (urb->status) { 178 case 0: /* success */ 179 break; 180 case -ECONNRESET: /* unlink */ 181 case -ENOENT: 182 case -ESHUTDOWN: 183 /* this urb is terminated, clean up */ 184 dev_dbg(dev, "%s - urb shutting down with status: %d", 185 __func__, urb->status); 186 return; 187 /* -EPIPE: should clear the halt */ 188 default: /* error */ 189 dev_dbg(dev, "%s - nonzero urb status received: %d", 190 __func__, urb->status); 191 goto resubmit; 192 } 193 194 dev_dbg(dev, "received following data cmd=0x%02x msb=0x%02x lsb=0x%02x", 195 data[0], data[1], data[2]); 196 197 usb_pcwd->cmd_command = data[0]; 198 usb_pcwd->cmd_data_msb = data[1]; 199 usb_pcwd->cmd_data_lsb = data[2]; 200 201 /* notify anyone waiting that the cmd has finished */ 202 atomic_set(&usb_pcwd->cmd_received, 1); 203 204 resubmit: 205 retval = usb_submit_urb(urb, GFP_ATOMIC); 206 if (retval) 207 pr_err("can't resubmit intr, usb_submit_urb failed with result %d\n", 208 retval); 209 } 210 211 static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd, 212 unsigned char cmd, unsigned char *msb, unsigned char *lsb) 213 { 214 int got_response, count; 215 unsigned char *buf; 216 217 /* We will not send any commands if the USB PCWD device does 218 * not exist */ 219 if ((!usb_pcwd) || (!usb_pcwd->exists)) 220 return -1; 221 222 buf = kmalloc(6, GFP_KERNEL); 223 if (buf == NULL) 224 return 0; 225 226 /* The USB PC Watchdog uses a 6 byte report format. 227 * The board currently uses only 3 of the six bytes of the report. */ 228 buf[0] = cmd; /* Byte 0 = CMD */ 229 buf[1] = *msb; /* Byte 1 = Data MSB */ 230 buf[2] = *lsb; /* Byte 2 = Data LSB */ 231 buf[3] = buf[4] = buf[5] = 0; /* All other bytes not used */ 232 233 dev_dbg(&usb_pcwd->interface->dev, 234 "sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x", 235 buf[0], buf[1], buf[2]); 236 237 atomic_set(&usb_pcwd->cmd_received, 0); 238 239 if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0), 240 HID_REQ_SET_REPORT, HID_DT_REPORT, 241 0x0200, usb_pcwd->interface_number, buf, 6, 242 USB_COMMAND_TIMEOUT) != 6) { 243 dev_dbg(&usb_pcwd->interface->dev, 244 "usb_pcwd_send_command: error in usb_control_msg for cmd 0x%x 0x%x 0x%x\n", 245 cmd, *msb, *lsb); 246 } 247 /* wait till the usb card processed the command, 248 * with a max. timeout of USB_COMMAND_TIMEOUT */ 249 got_response = 0; 250 for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response); 251 count++) { 252 mdelay(1); 253 if (atomic_read(&usb_pcwd->cmd_received)) 254 got_response = 1; 255 } 256 257 if ((got_response) && (cmd == usb_pcwd->cmd_command)) { 258 /* read back response */ 259 *msb = usb_pcwd->cmd_data_msb; 260 *lsb = usb_pcwd->cmd_data_lsb; 261 } 262 263 kfree(buf); 264 265 return got_response; 266 } 267 268 static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd) 269 { 270 unsigned char msb = 0x00; 271 unsigned char lsb = 0x00; 272 int retval; 273 274 /* Enable Watchdog */ 275 retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG, 276 &msb, &lsb); 277 278 if ((retval == 0) || (lsb == 0)) { 279 pr_err("Card did not acknowledge enable attempt\n"); 280 return -1; 281 } 282 283 return 0; 284 } 285 286 static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd) 287 { 288 unsigned char msb = 0xA5; 289 unsigned char lsb = 0xC3; 290 int retval; 291 292 /* Disable Watchdog */ 293 retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG, 294 &msb, &lsb); 295 296 if ((retval == 0) || (lsb != 0)) { 297 pr_err("Card did not acknowledge disable attempt\n"); 298 return -1; 299 } 300 301 return 0; 302 } 303 304 static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd) 305 { 306 unsigned char dummy; 307 308 /* Re-trigger Watchdog */ 309 usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy); 310 311 return 0; 312 } 313 314 static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t) 315 { 316 unsigned char msb = t / 256; 317 unsigned char lsb = t % 256; 318 319 if ((t < 0x0001) || (t > 0xFFFF)) 320 return -EINVAL; 321 322 /* Write new heartbeat to watchdog */ 323 usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb); 324 325 heartbeat = t; 326 return 0; 327 } 328 329 static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd, 330 int *temperature) 331 { 332 unsigned char msb, lsb; 333 334 usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb); 335 336 /* 337 * Convert celsius to fahrenheit, since this was 338 * the decided 'standard' for this return value. 339 */ 340 *temperature = (lsb * 9 / 5) + 32; 341 342 return 0; 343 } 344 345 static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd, 346 int *time_left) 347 { 348 unsigned char msb, lsb; 349 350 /* Read the time that's left before rebooting */ 351 /* Note: if the board is not yet armed then we will read 0xFFFF */ 352 usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb); 353 354 *time_left = (msb << 8) + lsb; 355 356 return 0; 357 } 358 359 /* 360 * /dev/watchdog handling 361 */ 362 363 static ssize_t usb_pcwd_write(struct file *file, const char __user *data, 364 size_t len, loff_t *ppos) 365 { 366 /* See if we got the magic character 'V' and reload the timer */ 367 if (len) { 368 if (!nowayout) { 369 size_t i; 370 371 /* note: just in case someone wrote the magic character 372 * five months ago... */ 373 expect_release = 0; 374 375 /* scan to see whether or not we got the 376 * magic character */ 377 for (i = 0; i != len; i++) { 378 char c; 379 if (get_user(c, data + i)) 380 return -EFAULT; 381 if (c == 'V') 382 expect_release = 42; 383 } 384 } 385 386 /* someone wrote to us, we should reload the timer */ 387 usb_pcwd_keepalive(usb_pcwd_device); 388 } 389 return len; 390 } 391 392 static long usb_pcwd_ioctl(struct file *file, unsigned int cmd, 393 unsigned long arg) 394 { 395 void __user *argp = (void __user *)arg; 396 int __user *p = argp; 397 static const struct watchdog_info ident = { 398 .options = WDIOF_KEEPALIVEPING | 399 WDIOF_SETTIMEOUT | 400 WDIOF_MAGICCLOSE, 401 .firmware_version = 1, 402 .identity = DRIVER_NAME, 403 }; 404 405 switch (cmd) { 406 case WDIOC_GETSUPPORT: 407 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0; 408 409 case WDIOC_GETSTATUS: 410 case WDIOC_GETBOOTSTATUS: 411 return put_user(0, p); 412 413 case WDIOC_GETTEMP: 414 { 415 int temperature; 416 417 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature)) 418 return -EFAULT; 419 420 return put_user(temperature, p); 421 } 422 423 case WDIOC_SETOPTIONS: 424 { 425 int new_options, retval = -EINVAL; 426 427 if (get_user(new_options, p)) 428 return -EFAULT; 429 430 if (new_options & WDIOS_DISABLECARD) { 431 usb_pcwd_stop(usb_pcwd_device); 432 retval = 0; 433 } 434 435 if (new_options & WDIOS_ENABLECARD) { 436 usb_pcwd_start(usb_pcwd_device); 437 retval = 0; 438 } 439 440 return retval; 441 } 442 443 case WDIOC_KEEPALIVE: 444 usb_pcwd_keepalive(usb_pcwd_device); 445 return 0; 446 447 case WDIOC_SETTIMEOUT: 448 { 449 int new_heartbeat; 450 451 if (get_user(new_heartbeat, p)) 452 return -EFAULT; 453 454 if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat)) 455 return -EINVAL; 456 457 usb_pcwd_keepalive(usb_pcwd_device); 458 } 459 /* fall through */ 460 461 case WDIOC_GETTIMEOUT: 462 return put_user(heartbeat, p); 463 464 case WDIOC_GETTIMELEFT: 465 { 466 int time_left; 467 468 if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left)) 469 return -EFAULT; 470 471 return put_user(time_left, p); 472 } 473 474 default: 475 return -ENOTTY; 476 } 477 } 478 479 static int usb_pcwd_open(struct inode *inode, struct file *file) 480 { 481 /* /dev/watchdog can only be opened once */ 482 if (test_and_set_bit(0, &is_active)) 483 return -EBUSY; 484 485 /* Activate */ 486 usb_pcwd_start(usb_pcwd_device); 487 usb_pcwd_keepalive(usb_pcwd_device); 488 return nonseekable_open(inode, file); 489 } 490 491 static int usb_pcwd_release(struct inode *inode, struct file *file) 492 { 493 /* 494 * Shut off the timer. 495 */ 496 if (expect_release == 42) { 497 usb_pcwd_stop(usb_pcwd_device); 498 } else { 499 pr_crit("Unexpected close, not stopping watchdog!\n"); 500 usb_pcwd_keepalive(usb_pcwd_device); 501 } 502 expect_release = 0; 503 clear_bit(0, &is_active); 504 return 0; 505 } 506 507 /* 508 * /dev/temperature handling 509 */ 510 511 static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data, 512 size_t len, loff_t *ppos) 513 { 514 int temperature; 515 516 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature)) 517 return -EFAULT; 518 519 if (copy_to_user(data, &temperature, 1)) 520 return -EFAULT; 521 522 return 1; 523 } 524 525 static int usb_pcwd_temperature_open(struct inode *inode, struct file *file) 526 { 527 return nonseekable_open(inode, file); 528 } 529 530 static int usb_pcwd_temperature_release(struct inode *inode, struct file *file) 531 { 532 return 0; 533 } 534 535 /* 536 * Notify system 537 */ 538 539 static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code, 540 void *unused) 541 { 542 if (code == SYS_DOWN || code == SYS_HALT) 543 usb_pcwd_stop(usb_pcwd_device); /* Turn the WDT off */ 544 545 return NOTIFY_DONE; 546 } 547 548 /* 549 * Kernel Interfaces 550 */ 551 552 static const struct file_operations usb_pcwd_fops = { 553 .owner = THIS_MODULE, 554 .llseek = no_llseek, 555 .write = usb_pcwd_write, 556 .unlocked_ioctl = usb_pcwd_ioctl, 557 .open = usb_pcwd_open, 558 .release = usb_pcwd_release, 559 }; 560 561 static struct miscdevice usb_pcwd_miscdev = { 562 .minor = WATCHDOG_MINOR, 563 .name = "watchdog", 564 .fops = &usb_pcwd_fops, 565 }; 566 567 static const struct file_operations usb_pcwd_temperature_fops = { 568 .owner = THIS_MODULE, 569 .llseek = no_llseek, 570 .read = usb_pcwd_temperature_read, 571 .open = usb_pcwd_temperature_open, 572 .release = usb_pcwd_temperature_release, 573 }; 574 575 static struct miscdevice usb_pcwd_temperature_miscdev = { 576 .minor = TEMP_MINOR, 577 .name = "temperature", 578 .fops = &usb_pcwd_temperature_fops, 579 }; 580 581 static struct notifier_block usb_pcwd_notifier = { 582 .notifier_call = usb_pcwd_notify_sys, 583 }; 584 585 /** 586 * usb_pcwd_delete 587 */ 588 static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd) 589 { 590 usb_free_urb(usb_pcwd->intr_urb); 591 if (usb_pcwd->intr_buffer != NULL) 592 usb_free_coherent(usb_pcwd->udev, usb_pcwd->intr_size, 593 usb_pcwd->intr_buffer, usb_pcwd->intr_dma); 594 kfree(usb_pcwd); 595 } 596 597 /** 598 * usb_pcwd_probe 599 * 600 * Called by the usb core when a new device is connected that it thinks 601 * this driver might be interested in. 602 */ 603 static int usb_pcwd_probe(struct usb_interface *interface, 604 const struct usb_device_id *id) 605 { 606 struct usb_device *udev = interface_to_usbdev(interface); 607 struct usb_host_interface *iface_desc; 608 struct usb_endpoint_descriptor *endpoint; 609 struct usb_pcwd_private *usb_pcwd = NULL; 610 int pipe; 611 int retval = -ENOMEM; 612 int got_fw_rev; 613 unsigned char fw_rev_major, fw_rev_minor; 614 char fw_ver_str[20]; 615 unsigned char option_switches, dummy; 616 617 cards_found++; 618 if (cards_found > 1) { 619 pr_err("This driver only supports 1 device\n"); 620 return -ENODEV; 621 } 622 623 /* get the active interface descriptor */ 624 iface_desc = interface->cur_altsetting; 625 626 /* check out that we have a HID device */ 627 if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) { 628 pr_err("The device isn't a Human Interface Device\n"); 629 return -ENODEV; 630 } 631 632 if (iface_desc->desc.bNumEndpoints < 1) 633 return -ENODEV; 634 635 /* check out the endpoint: it has to be Interrupt & IN */ 636 endpoint = &iface_desc->endpoint[0].desc; 637 638 if (!usb_endpoint_is_int_in(endpoint)) { 639 /* we didn't find a Interrupt endpoint with direction IN */ 640 pr_err("Couldn't find an INTR & IN endpoint\n"); 641 return -ENODEV; 642 } 643 644 /* get a handle to the interrupt data pipe */ 645 pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress); 646 647 /* allocate memory for our device and initialize it */ 648 usb_pcwd = kzalloc(sizeof(struct usb_pcwd_private), GFP_KERNEL); 649 if (usb_pcwd == NULL) 650 goto error; 651 652 usb_pcwd_device = usb_pcwd; 653 654 mutex_init(&usb_pcwd->mtx); 655 usb_pcwd->udev = udev; 656 usb_pcwd->interface = interface; 657 usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber; 658 usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ? 659 le16_to_cpu(endpoint->wMaxPacketSize) : 8); 660 661 /* set up the memory buffer's */ 662 usb_pcwd->intr_buffer = usb_alloc_coherent(udev, usb_pcwd->intr_size, 663 GFP_ATOMIC, &usb_pcwd->intr_dma); 664 if (!usb_pcwd->intr_buffer) { 665 pr_err("Out of memory\n"); 666 goto error; 667 } 668 669 /* allocate the urb's */ 670 usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL); 671 if (!usb_pcwd->intr_urb) 672 goto error; 673 674 /* initialise the intr urb's */ 675 usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe, 676 usb_pcwd->intr_buffer, usb_pcwd->intr_size, 677 usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval); 678 usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma; 679 usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 680 681 /* register our interrupt URB with the USB system */ 682 if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) { 683 pr_err("Problem registering interrupt URB\n"); 684 retval = -EIO; /* failure */ 685 goto error; 686 } 687 688 /* The device exists and can be communicated with */ 689 usb_pcwd->exists = 1; 690 691 /* disable card */ 692 usb_pcwd_stop(usb_pcwd); 693 694 /* Get the Firmware Version */ 695 got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION, 696 &fw_rev_major, &fw_rev_minor); 697 if (got_fw_rev) 698 sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor); 699 else 700 sprintf(fw_ver_str, "<card no answer>"); 701 702 pr_info("Found card (Firmware: %s) with temp option\n", fw_ver_str); 703 704 /* Get switch settings */ 705 usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy, 706 &option_switches); 707 708 pr_info("Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n", 709 option_switches, 710 ((option_switches & 0x10) ? "ON" : "OFF"), 711 ((option_switches & 0x08) ? "ON" : "OFF")); 712 713 /* If heartbeat = 0 then we use the heartbeat from the dip-switches */ 714 if (heartbeat == 0) 715 heartbeat = heartbeat_tbl[(option_switches & 0x07)]; 716 717 /* Check that the heartbeat value is within it's range ; 718 * if not reset to the default */ 719 if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) { 720 usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT); 721 pr_info("heartbeat value must be 0<heartbeat<65536, using %d\n", 722 WATCHDOG_HEARTBEAT); 723 } 724 725 retval = register_reboot_notifier(&usb_pcwd_notifier); 726 if (retval != 0) { 727 pr_err("cannot register reboot notifier (err=%d)\n", retval); 728 goto error; 729 } 730 731 retval = misc_register(&usb_pcwd_temperature_miscdev); 732 if (retval != 0) { 733 pr_err("cannot register miscdev on minor=%d (err=%d)\n", 734 TEMP_MINOR, retval); 735 goto err_out_unregister_reboot; 736 } 737 738 retval = misc_register(&usb_pcwd_miscdev); 739 if (retval != 0) { 740 pr_err("cannot register miscdev on minor=%d (err=%d)\n", 741 WATCHDOG_MINOR, retval); 742 goto err_out_misc_deregister; 743 } 744 745 /* we can register the device now, as it is ready */ 746 usb_set_intfdata(interface, usb_pcwd); 747 748 pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n", 749 heartbeat, nowayout); 750 751 return 0; 752 753 err_out_misc_deregister: 754 misc_deregister(&usb_pcwd_temperature_miscdev); 755 err_out_unregister_reboot: 756 unregister_reboot_notifier(&usb_pcwd_notifier); 757 error: 758 if (usb_pcwd) 759 usb_pcwd_delete(usb_pcwd); 760 usb_pcwd_device = NULL; 761 return retval; 762 } 763 764 765 /** 766 * usb_pcwd_disconnect 767 * 768 * Called by the usb core when the device is removed from the system. 769 * 770 * This routine guarantees that the driver will not submit any more urbs 771 * by clearing dev->udev. 772 */ 773 static void usb_pcwd_disconnect(struct usb_interface *interface) 774 { 775 struct usb_pcwd_private *usb_pcwd; 776 777 /* prevent races with open() */ 778 mutex_lock(&disconnect_mutex); 779 780 usb_pcwd = usb_get_intfdata(interface); 781 usb_set_intfdata(interface, NULL); 782 783 mutex_lock(&usb_pcwd->mtx); 784 785 /* Stop the timer before we leave */ 786 if (!nowayout) 787 usb_pcwd_stop(usb_pcwd); 788 789 /* We should now stop communicating with the USB PCWD device */ 790 usb_pcwd->exists = 0; 791 792 /* Deregister */ 793 misc_deregister(&usb_pcwd_miscdev); 794 misc_deregister(&usb_pcwd_temperature_miscdev); 795 unregister_reboot_notifier(&usb_pcwd_notifier); 796 797 mutex_unlock(&usb_pcwd->mtx); 798 799 /* Delete the USB PCWD device */ 800 usb_pcwd_delete(usb_pcwd); 801 802 cards_found--; 803 804 mutex_unlock(&disconnect_mutex); 805 806 pr_info("USB PC Watchdog disconnected\n"); 807 } 808 809 module_usb_driver(usb_pcwd_driver); 810