1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Berkshire USB-PC Watchdog Card Driver 4 * 5 * (c) Copyright 2004-2007 Wim Van Sebroeck <wim@iguana.be>. 6 * 7 * Based on source code of the following authors: 8 * Ken Hollis <kenji@bitgate.com>, 9 * Alan Cox <alan@lxorguk.ukuu.org.uk>, 10 * Matt Domsch <Matt_Domsch@dell.com>, 11 * Rob Radez <rob@osinvestor.com>, 12 * Greg Kroah-Hartman <greg@kroah.com> 13 * 14 * Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor 15 * provide warranty for any of this software. This material is 16 * provided "AS-IS" and at no charge. 17 * 18 * Thanks also to Simon Machell at Berkshire Products Inc. for 19 * providing the test hardware. More info is available at 20 * http://www.berkprod.com/ or http://www.pcwatchdog.com/ 21 */ 22 23 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 24 25 #include <linux/module.h> /* For module specific items */ 26 #include <linux/moduleparam.h> /* For new moduleparam's */ 27 #include <linux/types.h> /* For standard types (like size_t) */ 28 #include <linux/errno.h> /* For the -ENODEV/... values */ 29 #include <linux/kernel.h> /* For printk/panic/... */ 30 #include <linux/delay.h> /* For mdelay function */ 31 #include <linux/miscdevice.h> /* For struct miscdevice */ 32 #include <linux/watchdog.h> /* For the watchdog specific items */ 33 #include <linux/notifier.h> /* For notifier support */ 34 #include <linux/reboot.h> /* For reboot_notifier stuff */ 35 #include <linux/init.h> /* For __init/__exit/... */ 36 #include <linux/fs.h> /* For file operations */ 37 #include <linux/usb.h> /* For USB functions */ 38 #include <linux/slab.h> /* For kmalloc, ... */ 39 #include <linux/mutex.h> /* For mutex locking */ 40 #include <linux/hid.h> /* For HID_REQ_SET_REPORT & HID_DT_REPORT */ 41 #include <linux/uaccess.h> /* For copy_to_user/put_user/... */ 42 43 44 /* Module and Version Information */ 45 #define DRIVER_VERSION "1.02" 46 #define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>" 47 #define DRIVER_DESC "Berkshire USB-PC Watchdog driver" 48 #define DRIVER_NAME "pcwd_usb" 49 50 MODULE_AUTHOR(DRIVER_AUTHOR); 51 MODULE_DESCRIPTION(DRIVER_DESC); 52 MODULE_LICENSE("GPL"); 53 54 #define WATCHDOG_HEARTBEAT 0 /* default heartbeat = 55 delay-time from dip-switches */ 56 static int heartbeat = WATCHDOG_HEARTBEAT; 57 module_param(heartbeat, int, 0); 58 MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. " 59 "(0<heartbeat<65536 or 0=delay-time from dip-switches, default=" 60 __MODULE_STRING(WATCHDOG_HEARTBEAT) ")"); 61 62 static bool nowayout = WATCHDOG_NOWAYOUT; 63 module_param(nowayout, bool, 0); 64 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" 65 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); 66 67 /* The vendor and product id's for the USB-PC Watchdog card */ 68 #define USB_PCWD_VENDOR_ID 0x0c98 69 #define USB_PCWD_PRODUCT_ID 0x1140 70 71 /* table of devices that work with this driver */ 72 static const struct usb_device_id usb_pcwd_table[] = { 73 { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) }, 74 { } /* Terminating entry */ 75 }; 76 MODULE_DEVICE_TABLE(usb, usb_pcwd_table); 77 78 /* according to documentation max. time to process a command for the USB 79 * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */ 80 #define USB_COMMAND_TIMEOUT 250 81 82 /* Watchdog's internal commands */ 83 #define CMD_READ_TEMP 0x02 /* Read Temperature; 84 Re-trigger Watchdog */ 85 #define CMD_TRIGGER CMD_READ_TEMP 86 #define CMD_GET_STATUS 0x04 /* Get Status Information */ 87 #define CMD_GET_FIRMWARE_VERSION 0x08 /* Get Firmware Version */ 88 #define CMD_GET_DIP_SWITCH_SETTINGS 0x0c /* Get Dip Switch Settings */ 89 #define CMD_READ_WATCHDOG_TIMEOUT 0x18 /* Read Current Watchdog Time */ 90 #define CMD_WRITE_WATCHDOG_TIMEOUT 0x19 /* Write Current WatchdogTime */ 91 #define CMD_ENABLE_WATCHDOG 0x30 /* Enable / Disable Watchdog */ 92 #define CMD_DISABLE_WATCHDOG CMD_ENABLE_WATCHDOG 93 94 /* Watchdog's Dip Switch heartbeat values */ 95 static const int heartbeat_tbl[] = { 96 5, /* OFF-OFF-OFF = 5 Sec */ 97 10, /* OFF-OFF-ON = 10 Sec */ 98 30, /* OFF-ON-OFF = 30 Sec */ 99 60, /* OFF-ON-ON = 1 Min */ 100 300, /* ON-OFF-OFF = 5 Min */ 101 600, /* ON-OFF-ON = 10 Min */ 102 1800, /* ON-ON-OFF = 30 Min */ 103 3600, /* ON-ON-ON = 1 hour */ 104 }; 105 106 /* We can only use 1 card due to the /dev/watchdog restriction */ 107 static int cards_found; 108 109 /* some internal variables */ 110 static unsigned long is_active; 111 static char expect_release; 112 113 /* Structure to hold all of our device specific stuff */ 114 struct usb_pcwd_private { 115 /* save off the usb device pointer */ 116 struct usb_device *udev; 117 /* the interface for this device */ 118 struct usb_interface *interface; 119 120 /* the interface number used for cmd's */ 121 unsigned int interface_number; 122 123 /* the buffer to intr data */ 124 unsigned char *intr_buffer; 125 /* the dma address for the intr buffer */ 126 dma_addr_t intr_dma; 127 /* the size of the intr buffer */ 128 size_t intr_size; 129 /* the urb used for the intr pipe */ 130 struct urb *intr_urb; 131 132 /* The command that is reported back */ 133 unsigned char cmd_command; 134 /* The data MSB that is reported back */ 135 unsigned char cmd_data_msb; 136 /* The data LSB that is reported back */ 137 unsigned char cmd_data_lsb; 138 /* true if we received a report after a command */ 139 atomic_t cmd_received; 140 141 /* Wether or not the device exists */ 142 int exists; 143 /* locks this structure */ 144 struct mutex mtx; 145 }; 146 static struct usb_pcwd_private *usb_pcwd_device; 147 148 /* prevent races between open() and disconnect() */ 149 static DEFINE_MUTEX(disconnect_mutex); 150 151 /* local function prototypes */ 152 static int usb_pcwd_probe(struct usb_interface *interface, 153 const struct usb_device_id *id); 154 static void usb_pcwd_disconnect(struct usb_interface *interface); 155 156 /* usb specific object needed to register this driver with the usb subsystem */ 157 static struct usb_driver usb_pcwd_driver = { 158 .name = DRIVER_NAME, 159 .probe = usb_pcwd_probe, 160 .disconnect = usb_pcwd_disconnect, 161 .id_table = usb_pcwd_table, 162 }; 163 164 165 static void usb_pcwd_intr_done(struct urb *urb) 166 { 167 struct usb_pcwd_private *usb_pcwd = 168 (struct usb_pcwd_private *)urb->context; 169 unsigned char *data = usb_pcwd->intr_buffer; 170 struct device *dev = &usb_pcwd->interface->dev; 171 int retval; 172 173 switch (urb->status) { 174 case 0: /* success */ 175 break; 176 case -ECONNRESET: /* unlink */ 177 case -ENOENT: 178 case -ESHUTDOWN: 179 /* this urb is terminated, clean up */ 180 dev_dbg(dev, "%s - urb shutting down with status: %d", 181 __func__, urb->status); 182 return; 183 /* -EPIPE: should clear the halt */ 184 default: /* error */ 185 dev_dbg(dev, "%s - nonzero urb status received: %d", 186 __func__, urb->status); 187 goto resubmit; 188 } 189 190 dev_dbg(dev, "received following data cmd=0x%02x msb=0x%02x lsb=0x%02x", 191 data[0], data[1], data[2]); 192 193 usb_pcwd->cmd_command = data[0]; 194 usb_pcwd->cmd_data_msb = data[1]; 195 usb_pcwd->cmd_data_lsb = data[2]; 196 197 /* notify anyone waiting that the cmd has finished */ 198 atomic_set(&usb_pcwd->cmd_received, 1); 199 200 resubmit: 201 retval = usb_submit_urb(urb, GFP_ATOMIC); 202 if (retval) 203 pr_err("can't resubmit intr, usb_submit_urb failed with result %d\n", 204 retval); 205 } 206 207 static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd, 208 unsigned char cmd, unsigned char *msb, unsigned char *lsb) 209 { 210 int got_response, count; 211 unsigned char *buf; 212 213 /* We will not send any commands if the USB PCWD device does 214 * not exist */ 215 if ((!usb_pcwd) || (!usb_pcwd->exists)) 216 return -1; 217 218 buf = kmalloc(6, GFP_KERNEL); 219 if (buf == NULL) 220 return 0; 221 222 /* The USB PC Watchdog uses a 6 byte report format. 223 * The board currently uses only 3 of the six bytes of the report. */ 224 buf[0] = cmd; /* Byte 0 = CMD */ 225 buf[1] = *msb; /* Byte 1 = Data MSB */ 226 buf[2] = *lsb; /* Byte 2 = Data LSB */ 227 buf[3] = buf[4] = buf[5] = 0; /* All other bytes not used */ 228 229 dev_dbg(&usb_pcwd->interface->dev, 230 "sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x", 231 buf[0], buf[1], buf[2]); 232 233 atomic_set(&usb_pcwd->cmd_received, 0); 234 235 if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0), 236 HID_REQ_SET_REPORT, HID_DT_REPORT, 237 0x0200, usb_pcwd->interface_number, buf, 6, 238 USB_COMMAND_TIMEOUT) != 6) { 239 dev_dbg(&usb_pcwd->interface->dev, 240 "usb_pcwd_send_command: error in usb_control_msg for cmd 0x%x 0x%x 0x%x\n", 241 cmd, *msb, *lsb); 242 } 243 /* wait till the usb card processed the command, 244 * with a max. timeout of USB_COMMAND_TIMEOUT */ 245 got_response = 0; 246 for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response); 247 count++) { 248 mdelay(1); 249 if (atomic_read(&usb_pcwd->cmd_received)) 250 got_response = 1; 251 } 252 253 if ((got_response) && (cmd == usb_pcwd->cmd_command)) { 254 /* read back response */ 255 *msb = usb_pcwd->cmd_data_msb; 256 *lsb = usb_pcwd->cmd_data_lsb; 257 } 258 259 kfree(buf); 260 261 return got_response; 262 } 263 264 static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd) 265 { 266 unsigned char msb = 0x00; 267 unsigned char lsb = 0x00; 268 int retval; 269 270 /* Enable Watchdog */ 271 retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG, 272 &msb, &lsb); 273 274 if ((retval == 0) || (lsb == 0)) { 275 pr_err("Card did not acknowledge enable attempt\n"); 276 return -1; 277 } 278 279 return 0; 280 } 281 282 static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd) 283 { 284 unsigned char msb = 0xA5; 285 unsigned char lsb = 0xC3; 286 int retval; 287 288 /* Disable Watchdog */ 289 retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG, 290 &msb, &lsb); 291 292 if ((retval == 0) || (lsb != 0)) { 293 pr_err("Card did not acknowledge disable attempt\n"); 294 return -1; 295 } 296 297 return 0; 298 } 299 300 static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd) 301 { 302 unsigned char dummy; 303 304 /* Re-trigger Watchdog */ 305 usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy); 306 307 return 0; 308 } 309 310 static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t) 311 { 312 unsigned char msb = t / 256; 313 unsigned char lsb = t % 256; 314 315 if ((t < 0x0001) || (t > 0xFFFF)) 316 return -EINVAL; 317 318 /* Write new heartbeat to watchdog */ 319 usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb); 320 321 heartbeat = t; 322 return 0; 323 } 324 325 static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd, 326 int *temperature) 327 { 328 unsigned char msb, lsb; 329 330 usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb); 331 332 /* 333 * Convert celsius to fahrenheit, since this was 334 * the decided 'standard' for this return value. 335 */ 336 *temperature = (lsb * 9 / 5) + 32; 337 338 return 0; 339 } 340 341 static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd, 342 int *time_left) 343 { 344 unsigned char msb, lsb; 345 346 /* Read the time that's left before rebooting */ 347 /* Note: if the board is not yet armed then we will read 0xFFFF */ 348 usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb); 349 350 *time_left = (msb << 8) + lsb; 351 352 return 0; 353 } 354 355 /* 356 * /dev/watchdog handling 357 */ 358 359 static ssize_t usb_pcwd_write(struct file *file, const char __user *data, 360 size_t len, loff_t *ppos) 361 { 362 /* See if we got the magic character 'V' and reload the timer */ 363 if (len) { 364 if (!nowayout) { 365 size_t i; 366 367 /* note: just in case someone wrote the magic character 368 * five months ago... */ 369 expect_release = 0; 370 371 /* scan to see whether or not we got the 372 * magic character */ 373 for (i = 0; i != len; i++) { 374 char c; 375 if (get_user(c, data + i)) 376 return -EFAULT; 377 if (c == 'V') 378 expect_release = 42; 379 } 380 } 381 382 /* someone wrote to us, we should reload the timer */ 383 usb_pcwd_keepalive(usb_pcwd_device); 384 } 385 return len; 386 } 387 388 static long usb_pcwd_ioctl(struct file *file, unsigned int cmd, 389 unsigned long arg) 390 { 391 void __user *argp = (void __user *)arg; 392 int __user *p = argp; 393 static const struct watchdog_info ident = { 394 .options = WDIOF_KEEPALIVEPING | 395 WDIOF_SETTIMEOUT | 396 WDIOF_MAGICCLOSE, 397 .firmware_version = 1, 398 .identity = DRIVER_NAME, 399 }; 400 401 switch (cmd) { 402 case WDIOC_GETSUPPORT: 403 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0; 404 405 case WDIOC_GETSTATUS: 406 case WDIOC_GETBOOTSTATUS: 407 return put_user(0, p); 408 409 case WDIOC_GETTEMP: 410 { 411 int temperature; 412 413 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature)) 414 return -EFAULT; 415 416 return put_user(temperature, p); 417 } 418 419 case WDIOC_SETOPTIONS: 420 { 421 int new_options, retval = -EINVAL; 422 423 if (get_user(new_options, p)) 424 return -EFAULT; 425 426 if (new_options & WDIOS_DISABLECARD) { 427 usb_pcwd_stop(usb_pcwd_device); 428 retval = 0; 429 } 430 431 if (new_options & WDIOS_ENABLECARD) { 432 usb_pcwd_start(usb_pcwd_device); 433 retval = 0; 434 } 435 436 return retval; 437 } 438 439 case WDIOC_KEEPALIVE: 440 usb_pcwd_keepalive(usb_pcwd_device); 441 return 0; 442 443 case WDIOC_SETTIMEOUT: 444 { 445 int new_heartbeat; 446 447 if (get_user(new_heartbeat, p)) 448 return -EFAULT; 449 450 if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat)) 451 return -EINVAL; 452 453 usb_pcwd_keepalive(usb_pcwd_device); 454 } 455 fallthrough; 456 457 case WDIOC_GETTIMEOUT: 458 return put_user(heartbeat, p); 459 460 case WDIOC_GETTIMELEFT: 461 { 462 int time_left; 463 464 if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left)) 465 return -EFAULT; 466 467 return put_user(time_left, p); 468 } 469 470 default: 471 return -ENOTTY; 472 } 473 } 474 475 static int usb_pcwd_open(struct inode *inode, struct file *file) 476 { 477 /* /dev/watchdog can only be opened once */ 478 if (test_and_set_bit(0, &is_active)) 479 return -EBUSY; 480 481 /* Activate */ 482 usb_pcwd_start(usb_pcwd_device); 483 usb_pcwd_keepalive(usb_pcwd_device); 484 return stream_open(inode, file); 485 } 486 487 static int usb_pcwd_release(struct inode *inode, struct file *file) 488 { 489 /* 490 * Shut off the timer. 491 */ 492 if (expect_release == 42) { 493 usb_pcwd_stop(usb_pcwd_device); 494 } else { 495 pr_crit("Unexpected close, not stopping watchdog!\n"); 496 usb_pcwd_keepalive(usb_pcwd_device); 497 } 498 expect_release = 0; 499 clear_bit(0, &is_active); 500 return 0; 501 } 502 503 /* 504 * /dev/temperature handling 505 */ 506 507 static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data, 508 size_t len, loff_t *ppos) 509 { 510 int temperature; 511 512 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature)) 513 return -EFAULT; 514 515 if (copy_to_user(data, &temperature, 1)) 516 return -EFAULT; 517 518 return 1; 519 } 520 521 static int usb_pcwd_temperature_open(struct inode *inode, struct file *file) 522 { 523 return stream_open(inode, file); 524 } 525 526 static int usb_pcwd_temperature_release(struct inode *inode, struct file *file) 527 { 528 return 0; 529 } 530 531 /* 532 * Notify system 533 */ 534 535 static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code, 536 void *unused) 537 { 538 if (code == SYS_DOWN || code == SYS_HALT) 539 usb_pcwd_stop(usb_pcwd_device); /* Turn the WDT off */ 540 541 return NOTIFY_DONE; 542 } 543 544 /* 545 * Kernel Interfaces 546 */ 547 548 static const struct file_operations usb_pcwd_fops = { 549 .owner = THIS_MODULE, 550 .llseek = no_llseek, 551 .write = usb_pcwd_write, 552 .unlocked_ioctl = usb_pcwd_ioctl, 553 .compat_ioctl = compat_ptr_ioctl, 554 .open = usb_pcwd_open, 555 .release = usb_pcwd_release, 556 }; 557 558 static struct miscdevice usb_pcwd_miscdev = { 559 .minor = WATCHDOG_MINOR, 560 .name = "watchdog", 561 .fops = &usb_pcwd_fops, 562 }; 563 564 static const struct file_operations usb_pcwd_temperature_fops = { 565 .owner = THIS_MODULE, 566 .llseek = no_llseek, 567 .read = usb_pcwd_temperature_read, 568 .open = usb_pcwd_temperature_open, 569 .release = usb_pcwd_temperature_release, 570 }; 571 572 static struct miscdevice usb_pcwd_temperature_miscdev = { 573 .minor = TEMP_MINOR, 574 .name = "temperature", 575 .fops = &usb_pcwd_temperature_fops, 576 }; 577 578 static struct notifier_block usb_pcwd_notifier = { 579 .notifier_call = usb_pcwd_notify_sys, 580 }; 581 582 /** 583 * usb_pcwd_delete 584 */ 585 static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd) 586 { 587 usb_free_urb(usb_pcwd->intr_urb); 588 usb_free_coherent(usb_pcwd->udev, usb_pcwd->intr_size, 589 usb_pcwd->intr_buffer, usb_pcwd->intr_dma); 590 kfree(usb_pcwd); 591 } 592 593 /** 594 * usb_pcwd_probe 595 * 596 * Called by the usb core when a new device is connected that it thinks 597 * this driver might be interested in. 598 */ 599 static int usb_pcwd_probe(struct usb_interface *interface, 600 const struct usb_device_id *id) 601 { 602 struct usb_device *udev = interface_to_usbdev(interface); 603 struct usb_host_interface *iface_desc; 604 struct usb_endpoint_descriptor *endpoint; 605 struct usb_pcwd_private *usb_pcwd = NULL; 606 int pipe; 607 int retval = -ENOMEM; 608 int got_fw_rev; 609 unsigned char fw_rev_major, fw_rev_minor; 610 char fw_ver_str[20]; 611 unsigned char option_switches, dummy; 612 613 cards_found++; 614 if (cards_found > 1) { 615 pr_err("This driver only supports 1 device\n"); 616 return -ENODEV; 617 } 618 619 /* get the active interface descriptor */ 620 iface_desc = interface->cur_altsetting; 621 622 /* check out that we have a HID device */ 623 if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) { 624 pr_err("The device isn't a Human Interface Device\n"); 625 return -ENODEV; 626 } 627 628 if (iface_desc->desc.bNumEndpoints < 1) 629 return -ENODEV; 630 631 /* check out the endpoint: it has to be Interrupt & IN */ 632 endpoint = &iface_desc->endpoint[0].desc; 633 634 if (!usb_endpoint_is_int_in(endpoint)) { 635 /* we didn't find a Interrupt endpoint with direction IN */ 636 pr_err("Couldn't find an INTR & IN endpoint\n"); 637 return -ENODEV; 638 } 639 640 /* get a handle to the interrupt data pipe */ 641 pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress); 642 643 /* allocate memory for our device and initialize it */ 644 usb_pcwd = kzalloc(sizeof(struct usb_pcwd_private), GFP_KERNEL); 645 if (usb_pcwd == NULL) 646 goto error; 647 648 usb_pcwd_device = usb_pcwd; 649 650 mutex_init(&usb_pcwd->mtx); 651 usb_pcwd->udev = udev; 652 usb_pcwd->interface = interface; 653 usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber; 654 usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ? 655 le16_to_cpu(endpoint->wMaxPacketSize) : 8); 656 657 /* set up the memory buffer's */ 658 usb_pcwd->intr_buffer = usb_alloc_coherent(udev, usb_pcwd->intr_size, 659 GFP_ATOMIC, &usb_pcwd->intr_dma); 660 if (!usb_pcwd->intr_buffer) { 661 pr_err("Out of memory\n"); 662 goto error; 663 } 664 665 /* allocate the urb's */ 666 usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL); 667 if (!usb_pcwd->intr_urb) 668 goto error; 669 670 /* initialise the intr urb's */ 671 usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe, 672 usb_pcwd->intr_buffer, usb_pcwd->intr_size, 673 usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval); 674 usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma; 675 usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 676 677 /* register our interrupt URB with the USB system */ 678 if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) { 679 pr_err("Problem registering interrupt URB\n"); 680 retval = -EIO; /* failure */ 681 goto error; 682 } 683 684 /* The device exists and can be communicated with */ 685 usb_pcwd->exists = 1; 686 687 /* disable card */ 688 usb_pcwd_stop(usb_pcwd); 689 690 /* Get the Firmware Version */ 691 got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION, 692 &fw_rev_major, &fw_rev_minor); 693 if (got_fw_rev) 694 sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor); 695 else 696 sprintf(fw_ver_str, "<card no answer>"); 697 698 pr_info("Found card (Firmware: %s) with temp option\n", fw_ver_str); 699 700 /* Get switch settings */ 701 usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy, 702 &option_switches); 703 704 pr_info("Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n", 705 option_switches, 706 ((option_switches & 0x10) ? "ON" : "OFF"), 707 ((option_switches & 0x08) ? "ON" : "OFF")); 708 709 /* If heartbeat = 0 then we use the heartbeat from the dip-switches */ 710 if (heartbeat == 0) 711 heartbeat = heartbeat_tbl[(option_switches & 0x07)]; 712 713 /* Check that the heartbeat value is within it's range ; 714 * if not reset to the default */ 715 if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) { 716 usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT); 717 pr_info("heartbeat value must be 0<heartbeat<65536, using %d\n", 718 WATCHDOG_HEARTBEAT); 719 } 720 721 retval = register_reboot_notifier(&usb_pcwd_notifier); 722 if (retval != 0) { 723 pr_err("cannot register reboot notifier (err=%d)\n", retval); 724 goto error; 725 } 726 727 retval = misc_register(&usb_pcwd_temperature_miscdev); 728 if (retval != 0) { 729 pr_err("cannot register miscdev on minor=%d (err=%d)\n", 730 TEMP_MINOR, retval); 731 goto err_out_unregister_reboot; 732 } 733 734 retval = misc_register(&usb_pcwd_miscdev); 735 if (retval != 0) { 736 pr_err("cannot register miscdev on minor=%d (err=%d)\n", 737 WATCHDOG_MINOR, retval); 738 goto err_out_misc_deregister; 739 } 740 741 /* we can register the device now, as it is ready */ 742 usb_set_intfdata(interface, usb_pcwd); 743 744 pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n", 745 heartbeat, nowayout); 746 747 return 0; 748 749 err_out_misc_deregister: 750 misc_deregister(&usb_pcwd_temperature_miscdev); 751 err_out_unregister_reboot: 752 unregister_reboot_notifier(&usb_pcwd_notifier); 753 error: 754 if (usb_pcwd) 755 usb_pcwd_delete(usb_pcwd); 756 usb_pcwd_device = NULL; 757 return retval; 758 } 759 760 761 /** 762 * usb_pcwd_disconnect 763 * 764 * Called by the usb core when the device is removed from the system. 765 * 766 * This routine guarantees that the driver will not submit any more urbs 767 * by clearing dev->udev. 768 */ 769 static void usb_pcwd_disconnect(struct usb_interface *interface) 770 { 771 struct usb_pcwd_private *usb_pcwd; 772 773 /* prevent races with open() */ 774 mutex_lock(&disconnect_mutex); 775 776 usb_pcwd = usb_get_intfdata(interface); 777 usb_set_intfdata(interface, NULL); 778 779 mutex_lock(&usb_pcwd->mtx); 780 781 /* Stop the timer before we leave */ 782 if (!nowayout) 783 usb_pcwd_stop(usb_pcwd); 784 785 /* We should now stop communicating with the USB PCWD device */ 786 usb_pcwd->exists = 0; 787 788 /* Deregister */ 789 misc_deregister(&usb_pcwd_miscdev); 790 misc_deregister(&usb_pcwd_temperature_miscdev); 791 unregister_reboot_notifier(&usb_pcwd_notifier); 792 793 mutex_unlock(&usb_pcwd->mtx); 794 795 /* Delete the USB PCWD device */ 796 usb_pcwd_delete(usb_pcwd); 797 798 cards_found--; 799 800 mutex_unlock(&disconnect_mutex); 801 802 pr_info("USB PC Watchdog disconnected\n"); 803 } 804 805 module_usb_driver(usb_pcwd_driver); 806