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