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 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR) */ 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 #ifdef CONFIG_USB_DEBUG 48 static int debug = 1; 49 #else 50 static int debug; 51 #endif 52 53 /* Use our own dbg macro */ 54 55 #undef dbg 56 #ifndef DEBUG 57 #define DEBUG 58 #endif 59 #define dbg(format, ...) \ 60 do { \ 61 if (debug) \ 62 pr_debug(format "\n", ##__VA_ARGS__); \ 63 } while (0) 64 65 /* Module and Version Information */ 66 #define DRIVER_VERSION "1.02" 67 #define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>" 68 #define DRIVER_DESC "Berkshire USB-PC Watchdog driver" 69 #define DRIVER_LICENSE "GPL" 70 #define DRIVER_NAME "pcwd_usb" 71 72 MODULE_AUTHOR(DRIVER_AUTHOR); 73 MODULE_DESCRIPTION(DRIVER_DESC); 74 MODULE_LICENSE(DRIVER_LICENSE); 75 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); 76 MODULE_ALIAS_MISCDEV(TEMP_MINOR); 77 78 /* Module Parameters */ 79 module_param(debug, int, 0); 80 MODULE_PARM_DESC(debug, "Debug enabled or not"); 81 82 #define WATCHDOG_HEARTBEAT 0 /* default heartbeat = 83 delay-time from dip-switches */ 84 static int heartbeat = WATCHDOG_HEARTBEAT; 85 module_param(heartbeat, int, 0); 86 MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. " 87 "(0<heartbeat<65536 or 0=delay-time from dip-switches, default=" 88 __MODULE_STRING(WATCHDOG_HEARTBEAT) ")"); 89 90 static bool nowayout = WATCHDOG_NOWAYOUT; 91 module_param(nowayout, bool, 0); 92 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" 93 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); 94 95 /* The vendor and product id's for the USB-PC Watchdog card */ 96 #define USB_PCWD_VENDOR_ID 0x0c98 97 #define USB_PCWD_PRODUCT_ID 0x1140 98 99 /* table of devices that work with this driver */ 100 static struct usb_device_id usb_pcwd_table[] = { 101 { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) }, 102 { } /* Terminating entry */ 103 }; 104 MODULE_DEVICE_TABLE(usb, usb_pcwd_table); 105 106 /* according to documentation max. time to process a command for the USB 107 * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */ 108 #define USB_COMMAND_TIMEOUT 250 109 110 /* Watchdog's internal commands */ 111 #define CMD_READ_TEMP 0x02 /* Read Temperature; 112 Re-trigger Watchdog */ 113 #define CMD_TRIGGER CMD_READ_TEMP 114 #define CMD_GET_STATUS 0x04 /* Get Status Information */ 115 #define CMD_GET_FIRMWARE_VERSION 0x08 /* Get Firmware Version */ 116 #define CMD_GET_DIP_SWITCH_SETTINGS 0x0c /* Get Dip Switch Settings */ 117 #define CMD_READ_WATCHDOG_TIMEOUT 0x18 /* Read Current Watchdog Time */ 118 #define CMD_WRITE_WATCHDOG_TIMEOUT 0x19 /* Write Current WatchdogTime */ 119 #define CMD_ENABLE_WATCHDOG 0x30 /* Enable / Disable Watchdog */ 120 #define CMD_DISABLE_WATCHDOG CMD_ENABLE_WATCHDOG 121 122 /* Watchdog's Dip Switch heartbeat values */ 123 static const int heartbeat_tbl[] = { 124 5, /* OFF-OFF-OFF = 5 Sec */ 125 10, /* OFF-OFF-ON = 10 Sec */ 126 30, /* OFF-ON-OFF = 30 Sec */ 127 60, /* OFF-ON-ON = 1 Min */ 128 300, /* ON-OFF-OFF = 5 Min */ 129 600, /* ON-OFF-ON = 10 Min */ 130 1800, /* ON-ON-OFF = 30 Min */ 131 3600, /* ON-ON-ON = 1 hour */ 132 }; 133 134 /* We can only use 1 card due to the /dev/watchdog restriction */ 135 static int cards_found; 136 137 /* some internal variables */ 138 static unsigned long is_active; 139 static char expect_release; 140 141 /* Structure to hold all of our device specific stuff */ 142 struct usb_pcwd_private { 143 /* save off the usb device pointer */ 144 struct usb_device *udev; 145 /* the interface for this device */ 146 struct usb_interface *interface; 147 148 /* the interface number used for cmd's */ 149 unsigned int interface_number; 150 151 /* the buffer to intr data */ 152 unsigned char *intr_buffer; 153 /* the dma address for the intr buffer */ 154 dma_addr_t intr_dma; 155 /* the size of the intr buffer */ 156 size_t intr_size; 157 /* the urb used for the intr pipe */ 158 struct urb *intr_urb; 159 160 /* The command that is reported back */ 161 unsigned char cmd_command; 162 /* The data MSB that is reported back */ 163 unsigned char cmd_data_msb; 164 /* The data LSB that is reported back */ 165 unsigned char cmd_data_lsb; 166 /* true if we received a report after a command */ 167 atomic_t cmd_received; 168 169 /* Wether or not the device exists */ 170 int exists; 171 /* locks this structure */ 172 struct mutex mtx; 173 }; 174 static struct usb_pcwd_private *usb_pcwd_device; 175 176 /* prevent races between open() and disconnect() */ 177 static DEFINE_MUTEX(disconnect_mutex); 178 179 /* local function prototypes */ 180 static int usb_pcwd_probe(struct usb_interface *interface, 181 const struct usb_device_id *id); 182 static void usb_pcwd_disconnect(struct usb_interface *interface); 183 184 /* usb specific object needed to register this driver with the usb subsystem */ 185 static struct usb_driver usb_pcwd_driver = { 186 .name = DRIVER_NAME, 187 .probe = usb_pcwd_probe, 188 .disconnect = usb_pcwd_disconnect, 189 .id_table = usb_pcwd_table, 190 }; 191 192 193 static void usb_pcwd_intr_done(struct urb *urb) 194 { 195 struct usb_pcwd_private *usb_pcwd = 196 (struct usb_pcwd_private *)urb->context; 197 unsigned char *data = usb_pcwd->intr_buffer; 198 int retval; 199 200 switch (urb->status) { 201 case 0: /* success */ 202 break; 203 case -ECONNRESET: /* unlink */ 204 case -ENOENT: 205 case -ESHUTDOWN: 206 /* this urb is terminated, clean up */ 207 dbg("%s - urb shutting down with status: %d", __func__, 208 urb->status); 209 return; 210 /* -EPIPE: should clear the halt */ 211 default: /* error */ 212 dbg("%s - nonzero urb status received: %d", __func__, 213 urb->status); 214 goto resubmit; 215 } 216 217 dbg("received following data cmd=0x%02x msb=0x%02x lsb=0x%02x", 218 data[0], data[1], data[2]); 219 220 usb_pcwd->cmd_command = data[0]; 221 usb_pcwd->cmd_data_msb = data[1]; 222 usb_pcwd->cmd_data_lsb = data[2]; 223 224 /* notify anyone waiting that the cmd has finished */ 225 atomic_set(&usb_pcwd->cmd_received, 1); 226 227 resubmit: 228 retval = usb_submit_urb(urb, GFP_ATOMIC); 229 if (retval) 230 pr_err("can't resubmit intr, usb_submit_urb failed with result %d\n", 231 retval); 232 } 233 234 static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd, 235 unsigned char cmd, unsigned char *msb, unsigned char *lsb) 236 { 237 int got_response, count; 238 unsigned char buf[6]; 239 240 /* We will not send any commands if the USB PCWD device does 241 * not exist */ 242 if ((!usb_pcwd) || (!usb_pcwd->exists)) 243 return -1; 244 245 /* The USB PC Watchdog uses a 6 byte report format. 246 * The board currently uses only 3 of the six bytes of the report. */ 247 buf[0] = cmd; /* Byte 0 = CMD */ 248 buf[1] = *msb; /* Byte 1 = Data MSB */ 249 buf[2] = *lsb; /* Byte 2 = Data LSB */ 250 buf[3] = buf[4] = buf[5] = 0; /* All other bytes not used */ 251 252 dbg("sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x", 253 buf[0], buf[1], buf[2]); 254 255 atomic_set(&usb_pcwd->cmd_received, 0); 256 257 if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0), 258 HID_REQ_SET_REPORT, HID_DT_REPORT, 259 0x0200, usb_pcwd->interface_number, buf, sizeof(buf), 260 USB_COMMAND_TIMEOUT) != sizeof(buf)) { 261 dbg("usb_pcwd_send_command: error in usb_control_msg for " 262 "cmd 0x%x 0x%x 0x%x\n", cmd, *msb, *lsb); 263 } 264 /* wait till the usb card processed the command, 265 * with a max. timeout of USB_COMMAND_TIMEOUT */ 266 got_response = 0; 267 for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response); 268 count++) { 269 mdelay(1); 270 if (atomic_read(&usb_pcwd->cmd_received)) 271 got_response = 1; 272 } 273 274 if ((got_response) && (cmd == usb_pcwd->cmd_command)) { 275 /* read back response */ 276 *msb = usb_pcwd->cmd_data_msb; 277 *lsb = usb_pcwd->cmd_data_lsb; 278 } 279 280 return got_response; 281 } 282 283 static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd) 284 { 285 unsigned char msb = 0x00; 286 unsigned char lsb = 0x00; 287 int retval; 288 289 /* Enable Watchdog */ 290 retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG, 291 &msb, &lsb); 292 293 if ((retval == 0) || (lsb == 0)) { 294 pr_err("Card did not acknowledge enable attempt\n"); 295 return -1; 296 } 297 298 return 0; 299 } 300 301 static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd) 302 { 303 unsigned char msb = 0xA5; 304 unsigned char lsb = 0xC3; 305 int retval; 306 307 /* Disable Watchdog */ 308 retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG, 309 &msb, &lsb); 310 311 if ((retval == 0) || (lsb != 0)) { 312 pr_err("Card did not acknowledge disable attempt\n"); 313 return -1; 314 } 315 316 return 0; 317 } 318 319 static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd) 320 { 321 unsigned char dummy; 322 323 /* Re-trigger Watchdog */ 324 usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy); 325 326 return 0; 327 } 328 329 static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t) 330 { 331 unsigned char msb = t / 256; 332 unsigned char lsb = t % 256; 333 334 if ((t < 0x0001) || (t > 0xFFFF)) 335 return -EINVAL; 336 337 /* Write new heartbeat to watchdog */ 338 usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb); 339 340 heartbeat = t; 341 return 0; 342 } 343 344 static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd, 345 int *temperature) 346 { 347 unsigned char msb, lsb; 348 349 usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb); 350 351 /* 352 * Convert celsius to fahrenheit, since this was 353 * the decided 'standard' for this return value. 354 */ 355 *temperature = (lsb * 9 / 5) + 32; 356 357 return 0; 358 } 359 360 static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd, 361 int *time_left) 362 { 363 unsigned char msb, lsb; 364 365 /* Read the time that's left before rebooting */ 366 /* Note: if the board is not yet armed then we will read 0xFFFF */ 367 usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb); 368 369 *time_left = (msb << 8) + lsb; 370 371 return 0; 372 } 373 374 /* 375 * /dev/watchdog handling 376 */ 377 378 static ssize_t usb_pcwd_write(struct file *file, const char __user *data, 379 size_t len, loff_t *ppos) 380 { 381 /* See if we got the magic character 'V' and reload the timer */ 382 if (len) { 383 if (!nowayout) { 384 size_t i; 385 386 /* note: just in case someone wrote the magic character 387 * five months ago... */ 388 expect_release = 0; 389 390 /* scan to see whether or not we got the 391 * magic character */ 392 for (i = 0; i != len; i++) { 393 char c; 394 if (get_user(c, data + i)) 395 return -EFAULT; 396 if (c == 'V') 397 expect_release = 42; 398 } 399 } 400 401 /* someone wrote to us, we should reload the timer */ 402 usb_pcwd_keepalive(usb_pcwd_device); 403 } 404 return len; 405 } 406 407 static long usb_pcwd_ioctl(struct file *file, unsigned int cmd, 408 unsigned long arg) 409 { 410 void __user *argp = (void __user *)arg; 411 int __user *p = argp; 412 static const struct watchdog_info ident = { 413 .options = WDIOF_KEEPALIVEPING | 414 WDIOF_SETTIMEOUT | 415 WDIOF_MAGICCLOSE, 416 .firmware_version = 1, 417 .identity = DRIVER_NAME, 418 }; 419 420 switch (cmd) { 421 case WDIOC_GETSUPPORT: 422 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0; 423 424 case WDIOC_GETSTATUS: 425 case WDIOC_GETBOOTSTATUS: 426 return put_user(0, p); 427 428 case WDIOC_GETTEMP: 429 { 430 int temperature; 431 432 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature)) 433 return -EFAULT; 434 435 return put_user(temperature, p); 436 } 437 438 case WDIOC_SETOPTIONS: 439 { 440 int new_options, retval = -EINVAL; 441 442 if (get_user(new_options, p)) 443 return -EFAULT; 444 445 if (new_options & WDIOS_DISABLECARD) { 446 usb_pcwd_stop(usb_pcwd_device); 447 retval = 0; 448 } 449 450 if (new_options & WDIOS_ENABLECARD) { 451 usb_pcwd_start(usb_pcwd_device); 452 retval = 0; 453 } 454 455 return retval; 456 } 457 458 case WDIOC_KEEPALIVE: 459 usb_pcwd_keepalive(usb_pcwd_device); 460 return 0; 461 462 case WDIOC_SETTIMEOUT: 463 { 464 int new_heartbeat; 465 466 if (get_user(new_heartbeat, p)) 467 return -EFAULT; 468 469 if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat)) 470 return -EINVAL; 471 472 usb_pcwd_keepalive(usb_pcwd_device); 473 /* Fall */ 474 } 475 476 case WDIOC_GETTIMEOUT: 477 return put_user(heartbeat, p); 478 479 case WDIOC_GETTIMELEFT: 480 { 481 int time_left; 482 483 if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left)) 484 return -EFAULT; 485 486 return put_user(time_left, p); 487 } 488 489 default: 490 return -ENOTTY; 491 } 492 } 493 494 static int usb_pcwd_open(struct inode *inode, struct file *file) 495 { 496 /* /dev/watchdog can only be opened once */ 497 if (test_and_set_bit(0, &is_active)) 498 return -EBUSY; 499 500 /* Activate */ 501 usb_pcwd_start(usb_pcwd_device); 502 usb_pcwd_keepalive(usb_pcwd_device); 503 return nonseekable_open(inode, file); 504 } 505 506 static int usb_pcwd_release(struct inode *inode, struct file *file) 507 { 508 /* 509 * Shut off the timer. 510 */ 511 if (expect_release == 42) { 512 usb_pcwd_stop(usb_pcwd_device); 513 } else { 514 pr_crit("Unexpected close, not stopping watchdog!\n"); 515 usb_pcwd_keepalive(usb_pcwd_device); 516 } 517 expect_release = 0; 518 clear_bit(0, &is_active); 519 return 0; 520 } 521 522 /* 523 * /dev/temperature handling 524 */ 525 526 static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data, 527 size_t len, loff_t *ppos) 528 { 529 int temperature; 530 531 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature)) 532 return -EFAULT; 533 534 if (copy_to_user(data, &temperature, 1)) 535 return -EFAULT; 536 537 return 1; 538 } 539 540 static int usb_pcwd_temperature_open(struct inode *inode, struct file *file) 541 { 542 return nonseekable_open(inode, file); 543 } 544 545 static int usb_pcwd_temperature_release(struct inode *inode, struct file *file) 546 { 547 return 0; 548 } 549 550 /* 551 * Notify system 552 */ 553 554 static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code, 555 void *unused) 556 { 557 if (code == SYS_DOWN || code == SYS_HALT) 558 usb_pcwd_stop(usb_pcwd_device); /* Turn the WDT off */ 559 560 return NOTIFY_DONE; 561 } 562 563 /* 564 * Kernel Interfaces 565 */ 566 567 static const struct file_operations usb_pcwd_fops = { 568 .owner = THIS_MODULE, 569 .llseek = no_llseek, 570 .write = usb_pcwd_write, 571 .unlocked_ioctl = usb_pcwd_ioctl, 572 .open = usb_pcwd_open, 573 .release = usb_pcwd_release, 574 }; 575 576 static struct miscdevice usb_pcwd_miscdev = { 577 .minor = WATCHDOG_MINOR, 578 .name = "watchdog", 579 .fops = &usb_pcwd_fops, 580 }; 581 582 static const struct file_operations usb_pcwd_temperature_fops = { 583 .owner = THIS_MODULE, 584 .llseek = no_llseek, 585 .read = usb_pcwd_temperature_read, 586 .open = usb_pcwd_temperature_open, 587 .release = usb_pcwd_temperature_release, 588 }; 589 590 static struct miscdevice usb_pcwd_temperature_miscdev = { 591 .minor = TEMP_MINOR, 592 .name = "temperature", 593 .fops = &usb_pcwd_temperature_fops, 594 }; 595 596 static struct notifier_block usb_pcwd_notifier = { 597 .notifier_call = usb_pcwd_notify_sys, 598 }; 599 600 /** 601 * usb_pcwd_delete 602 */ 603 static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd) 604 { 605 usb_free_urb(usb_pcwd->intr_urb); 606 if (usb_pcwd->intr_buffer != NULL) 607 usb_free_coherent(usb_pcwd->udev, usb_pcwd->intr_size, 608 usb_pcwd->intr_buffer, usb_pcwd->intr_dma); 609 kfree(usb_pcwd); 610 } 611 612 /** 613 * usb_pcwd_probe 614 * 615 * Called by the usb core when a new device is connected that it thinks 616 * this driver might be interested in. 617 */ 618 static int usb_pcwd_probe(struct usb_interface *interface, 619 const struct usb_device_id *id) 620 { 621 struct usb_device *udev = interface_to_usbdev(interface); 622 struct usb_host_interface *iface_desc; 623 struct usb_endpoint_descriptor *endpoint; 624 struct usb_pcwd_private *usb_pcwd = NULL; 625 int pipe, maxp; 626 int retval = -ENOMEM; 627 int got_fw_rev; 628 unsigned char fw_rev_major, fw_rev_minor; 629 char fw_ver_str[20]; 630 unsigned char option_switches, dummy; 631 632 cards_found++; 633 if (cards_found > 1) { 634 pr_err("This driver only supports 1 device\n"); 635 return -ENODEV; 636 } 637 638 /* get the active interface descriptor */ 639 iface_desc = interface->cur_altsetting; 640 641 /* check out that we have a HID device */ 642 if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) { 643 pr_err("The device isn't a Human Interface Device\n"); 644 return -ENODEV; 645 } 646 647 /* check out the endpoint: it has to be Interrupt & IN */ 648 endpoint = &iface_desc->endpoint[0].desc; 649 650 if (!usb_endpoint_is_int_in(endpoint)) { 651 /* we didn't find a Interrupt endpoint with direction IN */ 652 pr_err("Couldn't find an INTR & IN endpoint\n"); 653 return -ENODEV; 654 } 655 656 /* get a handle to the interrupt data pipe */ 657 pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress); 658 maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe)); 659 660 /* allocate memory for our device and initialize it */ 661 usb_pcwd = kzalloc(sizeof(struct usb_pcwd_private), GFP_KERNEL); 662 if (usb_pcwd == NULL) { 663 pr_err("Out of memory\n"); 664 goto error; 665 } 666 667 usb_pcwd_device = usb_pcwd; 668 669 mutex_init(&usb_pcwd->mtx); 670 usb_pcwd->udev = udev; 671 usb_pcwd->interface = interface; 672 usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber; 673 usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ? 674 le16_to_cpu(endpoint->wMaxPacketSize) : 8); 675 676 /* set up the memory buffer's */ 677 usb_pcwd->intr_buffer = usb_alloc_coherent(udev, usb_pcwd->intr_size, 678 GFP_ATOMIC, &usb_pcwd->intr_dma); 679 if (!usb_pcwd->intr_buffer) { 680 pr_err("Out of memory\n"); 681 goto error; 682 } 683 684 /* allocate the urb's */ 685 usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL); 686 if (!usb_pcwd->intr_urb) { 687 pr_err("Out of memory\n"); 688 goto error; 689 } 690 691 /* initialise the intr urb's */ 692 usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe, 693 usb_pcwd->intr_buffer, usb_pcwd->intr_size, 694 usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval); 695 usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma; 696 usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 697 698 /* register our interrupt URB with the USB system */ 699 if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) { 700 pr_err("Problem registering interrupt URB\n"); 701 retval = -EIO; /* failure */ 702 goto error; 703 } 704 705 /* The device exists and can be communicated with */ 706 usb_pcwd->exists = 1; 707 708 /* disable card */ 709 usb_pcwd_stop(usb_pcwd); 710 711 /* Get the Firmware Version */ 712 got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION, 713 &fw_rev_major, &fw_rev_minor); 714 if (got_fw_rev) 715 sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor); 716 else 717 sprintf(fw_ver_str, "<card no answer>"); 718 719 pr_info("Found card (Firmware: %s) with temp option\n", fw_ver_str); 720 721 /* Get switch settings */ 722 usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy, 723 &option_switches); 724 725 pr_info("Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n", 726 option_switches, 727 ((option_switches & 0x10) ? "ON" : "OFF"), 728 ((option_switches & 0x08) ? "ON" : "OFF")); 729 730 /* If heartbeat = 0 then we use the heartbeat from the dip-switches */ 731 if (heartbeat == 0) 732 heartbeat = heartbeat_tbl[(option_switches & 0x07)]; 733 734 /* Check that the heartbeat value is within it's range ; 735 * if not reset to the default */ 736 if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) { 737 usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT); 738 pr_info("heartbeat value must be 0<heartbeat<65536, using %d\n", 739 WATCHDOG_HEARTBEAT); 740 } 741 742 retval = register_reboot_notifier(&usb_pcwd_notifier); 743 if (retval != 0) { 744 pr_err("cannot register reboot notifier (err=%d)\n", retval); 745 goto error; 746 } 747 748 retval = misc_register(&usb_pcwd_temperature_miscdev); 749 if (retval != 0) { 750 pr_err("cannot register miscdev on minor=%d (err=%d)\n", 751 TEMP_MINOR, retval); 752 goto err_out_unregister_reboot; 753 } 754 755 retval = misc_register(&usb_pcwd_miscdev); 756 if (retval != 0) { 757 pr_err("cannot register miscdev on minor=%d (err=%d)\n", 758 WATCHDOG_MINOR, retval); 759 goto err_out_misc_deregister; 760 } 761 762 /* we can register the device now, as it is ready */ 763 usb_set_intfdata(interface, usb_pcwd); 764 765 pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n", 766 heartbeat, nowayout); 767 768 return 0; 769 770 err_out_misc_deregister: 771 misc_deregister(&usb_pcwd_temperature_miscdev); 772 err_out_unregister_reboot: 773 unregister_reboot_notifier(&usb_pcwd_notifier); 774 error: 775 if (usb_pcwd) 776 usb_pcwd_delete(usb_pcwd); 777 usb_pcwd_device = NULL; 778 return retval; 779 } 780 781 782 /** 783 * usb_pcwd_disconnect 784 * 785 * Called by the usb core when the device is removed from the system. 786 * 787 * This routine guarantees that the driver will not submit any more urbs 788 * by clearing dev->udev. 789 */ 790 static void usb_pcwd_disconnect(struct usb_interface *interface) 791 { 792 struct usb_pcwd_private *usb_pcwd; 793 794 /* prevent races with open() */ 795 mutex_lock(&disconnect_mutex); 796 797 usb_pcwd = usb_get_intfdata(interface); 798 usb_set_intfdata(interface, NULL); 799 800 mutex_lock(&usb_pcwd->mtx); 801 802 /* Stop the timer before we leave */ 803 if (!nowayout) 804 usb_pcwd_stop(usb_pcwd); 805 806 /* We should now stop communicating with the USB PCWD device */ 807 usb_pcwd->exists = 0; 808 809 /* Deregister */ 810 misc_deregister(&usb_pcwd_miscdev); 811 misc_deregister(&usb_pcwd_temperature_miscdev); 812 unregister_reboot_notifier(&usb_pcwd_notifier); 813 814 mutex_unlock(&usb_pcwd->mtx); 815 816 /* Delete the USB PCWD device */ 817 usb_pcwd_delete(usb_pcwd); 818 819 cards_found--; 820 821 mutex_unlock(&disconnect_mutex); 822 823 pr_info("USB PC Watchdog disconnected\n"); 824 } 825 826 module_usb_driver(usb_pcwd_driver); 827