drivers/char/watchdog/pcwd_usb.c

   1 /*
   2  *      Berkshire USB-PC Watchdog Card Driver
   3  *
   4  *      (c) Copyright 2004 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@redhat.com>,
   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 #include <linux/module.h>       /* For module specific items */
  28 #include <linux/moduleparam.h>  /* For new moduleparam's */
  29 #include <linux/types.h>        /* For standard types (like size_t) */
  30 #include <linux/errno.h>        /* For the -ENODEV/... values */
  31 #include <linux/kernel.h>       /* For printk/panic/... */
  32 #include <linux/delay.h>        /* For mdelay function */
  33 #include <linux/miscdevice.h>   /* For MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR) */
  34 #include <linux/watchdog.h>     /* For the watchdog specific items */
  35 #include <linux/notifier.h>     /* For notifier support */
  36 #include <linux/reboot.h>       /* For reboot_notifier stuff */
  37 #include <linux/init.h>         /* For __init/__exit/... */
  38 #include <linux/fs.h>           /* For file operations */
  39 #include <linux/usb.h>          /* For USB functions */
  40 #include <linux/slab.h>         /* For kmalloc, ... */
  41 #include <linux/mutex.h>        /* For mutex locking */
  42 #include <linux/hid.h>          /* For HID_REQ_SET_REPORT & HID_DT_REPORT */
  43
  44 #include <asm/uaccess.h>        /* For copy_to_user/put_user/... */
  45
  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 #undef dbg
  55 #define dbg(format, arg...) do { if (debug) printk(KERN_DEBUG PFX format "\n" , ## arg); } while (0)
  56
  57
  58 /* Module and Version Information */
  59 #define DRIVER_VERSION "1.01"
  60 #define DRIVER_DATE "15 Mar 2005"
  61 #define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>"
  62 #define DRIVER_DESC "Berkshire USB-PC Watchdog driver"
  63 #define DRIVER_LICENSE "GPL"
  64 #define DRIVER_NAME "pcwd_usb"
  65 #define PFX DRIVER_NAME ": "
  66
  67 MODULE_AUTHOR(DRIVER_AUTHOR);
  68 MODULE_DESCRIPTION(DRIVER_DESC);
  69 MODULE_LICENSE(DRIVER_LICENSE);
  70 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
  71 MODULE_ALIAS_MISCDEV(TEMP_MINOR);
  72
  73 /* Module Parameters */
  74 module_param(debug, int, 0);
  75 MODULE_PARM_DESC(debug, "Debug enabled or not");
  76
  77 #define WATCHDOG_HEARTBEAT 2    /* 2 sec default heartbeat */
  78 static int heartbeat = WATCHDOG_HEARTBEAT;
  79 module_param(heartbeat, int, 0);
  80 MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (0<heartbeat<65536, default=" __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
  81
  82 static int nowayout = WATCHDOG_NOWAYOUT;
  83 module_param(nowayout, int, 0);
  84 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
  85
  86 /* The vendor and product id's for the USB-PC Watchdog card */
  87 #define USB_PCWD_VENDOR_ID      0x0c98
  88 #define USB_PCWD_PRODUCT_ID     0x1140
  89
  90 /* table of devices that work with this driver */
  91 static struct usb_device_id usb_pcwd_table [] = {
  92         { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) },
  93         { }                                     /* Terminating entry */
  94 };
  95 MODULE_DEVICE_TABLE (usb, usb_pcwd_table);
  96
  97 /* according to documentation max. time to process a command for the USB
  98  * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */
  99 #define USB_COMMAND_TIMEOUT     250
 100
 101 /* Watchdog's internal commands */
 102 #define CMD_READ_TEMP                   0x02    /* Read Temperature; Re-trigger Watchdog */
 103 #define CMD_TRIGGER                     CMD_READ_TEMP
 104 #define CMD_GET_STATUS                  0x04    /* Get Status Information */
 105 #define CMD_GET_FIRMWARE_VERSION        0x08    /* Get Firmware Version */
 106 #define CMD_GET_DIP_SWITCH_SETTINGS     0x0c    /* Get Dip Switch Settings */
 107 #define CMD_READ_WATCHDOG_TIMEOUT       0x18    /* Read Current Watchdog Time */
 108 #define CMD_WRITE_WATCHDOG_TIMEOUT      0x19    /* Write Current Watchdog Time */
 109 #define CMD_ENABLE_WATCHDOG             0x30    /* Enable / Disable Watchdog */
 110 #define CMD_DISABLE_WATCHDOG            CMD_ENABLE_WATCHDOG
 111
 112 /* We can only use 1 card due to the /dev/watchdog restriction */
 113 static int cards_found;
 114
 115 /* some internal variables */
 116 static unsigned long is_active;
 117 static char expect_release;
 118
 119 /* Structure to hold all of our device specific stuff */
 120 struct usb_pcwd_private {
 121         struct usb_device *     udev;                   /* save off the usb device pointer */
 122         struct usb_interface *  interface;              /* the interface for this device */
 123
 124         unsigned int            interface_number;       /* the interface number used for cmd's */
 125
 126         unsigned char *         intr_buffer;            /* the buffer to intr data */
 127         dma_addr_t              intr_dma;               /* the dma address for the intr buffer */
 128         size_t                  intr_size;              /* the size of the intr buffer */
 129         struct urb *            intr_urb;               /* the urb used for the intr pipe */
 130
 131         unsigned char           cmd_command;            /* The command that is reported back */
 132         unsigned char           cmd_data_msb;           /* The data MSB that is reported back */
 133         unsigned char           cmd_data_lsb;           /* The data LSB that is reported back */
 134         atomic_t                cmd_received;           /* true if we received a report after a command */
 135
 136         int                     exists;                 /* Wether or not the device exists */
 137         struct semaphore        sem;                    /* locks this structure */
 138 };
 139 static struct usb_pcwd_private *usb_pcwd_device;
 140
 141 /* prevent races between open() and disconnect() */
 142 static DEFINE_MUTEX(disconnect_mutex);
 143
 144 /* local function prototypes */
 145 static int usb_pcwd_probe       (struct usb_interface *interface, const struct usb_device_id *id);
 146 static void usb_pcwd_disconnect (struct usb_interface *interface);
 147
 148 /* usb specific object needed to register this driver with the usb subsystem */
 149 static struct usb_driver usb_pcwd_driver = {
 150         .name =         DRIVER_NAME,
 151         .probe =        usb_pcwd_probe,
 152         .disconnect =   usb_pcwd_disconnect,
 153         .id_table =     usb_pcwd_table,
 154 };
 155
 156
 157 static void usb_pcwd_intr_done(struct urb *urb)
 158 {
 159         struct usb_pcwd_private *usb_pcwd = (struct usb_pcwd_private *)urb->context;
 160         unsigned char *data = usb_pcwd->intr_buffer;
 161         int retval;
 162
 163         switch (urb->status) {
 164         case 0:                 /* success */
 165                 break;
 166         case -ECONNRESET:       /* unlink */
 167         case -ENOENT:
 168         case -ESHUTDOWN:
 169                 /* this urb is terminated, clean up */
 170                 dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
 171                 return;
 172         /* -EPIPE:  should clear the halt */
 173         default:                /* error */
 174                 dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
 175                 goto resubmit;
 176         }
 177
 178         dbg("received following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
 179                 data[0], data[1], data[2]);
 180
 181         usb_pcwd->cmd_command  = data[0];
 182         usb_pcwd->cmd_data_msb = data[1];
 183         usb_pcwd->cmd_data_lsb = data[2];
 184
 185         /* notify anyone waiting that the cmd has finished */
 186         atomic_set (&usb_pcwd->cmd_received, 1);
 187
 188 resubmit:
 189         retval = usb_submit_urb (urb, GFP_ATOMIC);
 190         if (retval)
 191                 printk(KERN_ERR PFX "can't resubmit intr, usb_submit_urb failed with result %d\n",
 192                         retval);
 193 }
 194
 195 static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd, unsigned char cmd,
 196         unsigned char *msb, unsigned char *lsb)
 197 {
 198         int got_response, count;
 199         unsigned char buf[6];
 200
 201         /* We will not send any commands if the USB PCWD device does not exist */
 202         if ((!usb_pcwd) || (!usb_pcwd->exists))
 203                 return -1;
 204
 205         /* The USB PC Watchdog uses a 6 byte report format. The board currently uses
 206          * only 3 of the six bytes of the report. */
 207         buf[0] = cmd;                   /* Byte 0 = CMD */
 208         buf[1] = *msb;                  /* Byte 1 = Data MSB */
 209         buf[2] = *lsb;                  /* Byte 2 = Data LSB */
 210         buf[3] = buf[4] = buf[5] = 0;   /* All other bytes not used */
 211
 212         dbg("sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
 213                 buf[0], buf[1], buf[2]);
 214
 215         atomic_set (&usb_pcwd->cmd_received, 0);
 216
 217         if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0),
 218                         HID_REQ_SET_REPORT, HID_DT_REPORT,
 219                         0x0200, usb_pcwd->interface_number, buf, sizeof(buf),
 220                         USB_COMMAND_TIMEOUT) != sizeof(buf)) {
 221                 dbg("usb_pcwd_send_command: error in usb_control_msg for cmd 0x%x 0x%x 0x%x\n", cmd, *msb, *lsb);
 222         }
 223         /* wait till the usb card processed the command,
 224          * with a max. timeout of USB_COMMAND_TIMEOUT */
 225         got_response = 0;
 226         for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response); count++) {
 227                 mdelay(1);
 228                 if (atomic_read (&usb_pcwd->cmd_received))
 229                         got_response = 1;
 230         }
 231
 232         if ((got_response) && (cmd == usb_pcwd->cmd_command)) {
 233                 /* read back response */
 234                 *msb = usb_pcwd->cmd_data_msb;
 235                 *lsb = usb_pcwd->cmd_data_lsb;
 236         }
 237
 238         return got_response;
 239 }
 240
 241 static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd)
 242 {
 243         unsigned char msb = 0x00;
 244         unsigned char lsb = 0x00;
 245         int retval;
 246
 247         /* Enable Watchdog */
 248         retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG, &msb, &lsb);
 249
 250         if ((retval == 0) || (lsb == 0)) {
 251                 printk(KERN_ERR PFX "Card did not acknowledge enable attempt\n");
 252                 return -1;
 253         }
 254
 255         return 0;
 256 }
 257
 258 static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd)
 259 {
 260         unsigned char msb = 0xA5;
 261         unsigned char lsb = 0xC3;
 262         int retval;
 263
 264         /* Disable Watchdog */
 265         retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG, &msb, &lsb);
 266
 267         if ((retval == 0) || (lsb != 0)) {
 268                 printk(KERN_ERR PFX "Card did not acknowledge disable attempt\n");
 269                 return -1;
 270         }
 271
 272         return 0;
 273 }
 274
 275 static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd)
 276 {
 277         unsigned char dummy;
 278
 279         /* Re-trigger Watchdog */
 280         usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy);
 281
 282         return 0;
 283 }
 284
 285 static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t)
 286 {
 287         unsigned char msb = t / 256;
 288         unsigned char lsb = t % 256;
 289
 290         if ((t < 0x0001) || (t > 0xFFFF))
 291                 return -EINVAL;
 292
 293         /* Write new heartbeat to watchdog */
 294         usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb);
 295
 296         heartbeat = t;
 297         return 0;
 298 }
 299
 300 static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd, int *temperature)
 301 {
 302         unsigned char msb, lsb;
 303
 304         usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb);
 305
 306         /*
 307          * Convert celsius to fahrenheit, since this was
 308          * the decided 'standard' for this return value.
 309          */
 310         *temperature = (lsb * 9 / 5) + 32;
 311
 312         return 0;
 313 }
 314
 315 static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd, int *time_left)
 316 {
 317         unsigned char msb, lsb;
 318
 319         /* Read the time that's left before rebooting */
 320         /* Note: if the board is not yet armed then we will read 0xFFFF */
 321         usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
 322
 323         *time_left = (msb << 8) + lsb;
 324
 325         return 0;
 326 }
 327
 328 /*
 329  *      /dev/watchdog handling
 330  */
 331
 332 static ssize_t usb_pcwd_write(struct file *file, const char __user *data,
 333                               size_t len, loff_t *ppos)
 334 {
 335         /* See if we got the magic character 'V' and reload the timer */
 336         if (len) {
 337                 if (!nowayout) {
 338                         size_t i;
 339
 340                         /* note: just in case someone wrote the magic character
 341                          * five months ago... */
 342                         expect_release = 0;
 343
 344                         /* scan to see whether or not we got the magic character */
 345                         for (i = 0; i != len; i++) {
 346                                 char c;
 347                                 if(get_user(c, data+i))
 348                                         return -EFAULT;
 349                                 if (c == 'V')
 350                                         expect_release = 42;
 351                         }
 352                 }
 353
 354                 /* someone wrote to us, we should reload the timer */
 355                 usb_pcwd_keepalive(usb_pcwd_device);
 356         }
 357         return len;
 358 }
 359
 360 static int usb_pcwd_ioctl(struct inode *inode, struct file *file,
 361                           unsigned int cmd, unsigned long arg)
 362 {
 363         void __user *argp = (void __user *)arg;
 364         int __user *p = argp;
 365         static struct watchdog_info ident = {
 366                 .options =              WDIOF_KEEPALIVEPING |
 367                                         WDIOF_SETTIMEOUT |
 368                                         WDIOF_MAGICCLOSE,
 369                 .firmware_version =     1,
 370                 .identity =             DRIVER_NAME,
 371         };
 372
 373         switch (cmd) {
 374                 case WDIOC_GETSUPPORT:
 375                         return copy_to_user(argp, &ident,
 376                                 sizeof (ident)) ? -EFAULT : 0;
 377
 378                 case WDIOC_GETSTATUS:
 379                 case WDIOC_GETBOOTSTATUS:
 380                         return put_user(0, p);
 381
 382                 case WDIOC_GETTEMP:
 383                 {
 384                         int temperature;
 385
 386                         if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
 387                                 return -EFAULT;
 388
 389                         return put_user(temperature, p);
 390                 }
 391
 392                 case WDIOC_KEEPALIVE:
 393                         usb_pcwd_keepalive(usb_pcwd_device);
 394                         return 0;
 395
 396                 case WDIOC_SETOPTIONS:
 397                 {
 398                         int new_options, retval = -EINVAL;
 399
 400                         if (get_user (new_options, p))
 401                                 return -EFAULT;
 402
 403                         if (new_options & WDIOS_DISABLECARD) {
 404                                 usb_pcwd_stop(usb_pcwd_device);
 405                                 retval = 0;
 406                         }
 407
 408                         if (new_options & WDIOS_ENABLECARD) {
 409                                 usb_pcwd_start(usb_pcwd_device);
 410                                 retval = 0;
 411                         }
 412
 413                         return retval;
 414                 }
 415
 416                 case WDIOC_SETTIMEOUT:
 417                 {
 418                         int new_heartbeat;
 419
 420                         if (get_user(new_heartbeat, p))
 421                                 return -EFAULT;
 422
 423                         if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
 424                             return -EINVAL;
 425
 426                         usb_pcwd_keepalive(usb_pcwd_device);
 427                         /* Fall */
 428                 }
 429
 430                 case WDIOC_GETTIMEOUT:
 431                         return put_user(heartbeat, p);
 432
 433                 case WDIOC_GETTIMELEFT:
 434                 {
 435                         int time_left;
 436
 437                         if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left))
 438                                 return -EFAULT;
 439
 440                         return put_user(time_left, p);
 441                 }
 442
 443                 default:
 444                         return -ENOTTY;
 445         }
 446 }
 447
 448 static int usb_pcwd_open(struct inode *inode, struct file *file)
 449 {
 450         /* /dev/watchdog can only be opened once */
 451         if (test_and_set_bit(0, &is_active))
 452                 return -EBUSY;
 453
 454         /* Activate */
 455         usb_pcwd_start(usb_pcwd_device);
 456         usb_pcwd_keepalive(usb_pcwd_device);
 457         return nonseekable_open(inode, file);
 458 }
 459
 460 static int usb_pcwd_release(struct inode *inode, struct file *file)
 461 {
 462         /*
 463          *      Shut off the timer.
 464          */
 465         if (expect_release == 42) {
 466                 usb_pcwd_stop(usb_pcwd_device);
 467         } else {
 468                 printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
 469                 usb_pcwd_keepalive(usb_pcwd_device);
 470         }
 471         expect_release = 0;
 472         clear_bit(0, &is_active);
 473         return 0;
 474 }
 475
 476 /*
 477  *      /dev/temperature handling
 478  */
 479
 480 static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data,
 481                                 size_t len, loff_t *ppos)
 482 {
 483         int temperature;
 484
 485         if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
 486                 return -EFAULT;
 487
 488         if (copy_to_user(data, &temperature, 1))
 489                 return -EFAULT;
 490
 491         return 1;
 492 }
 493
 494 static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
 495 {
 496         return nonseekable_open(inode, file);
 497 }
 498
 499 static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
 500 {
 501         return 0;
 502 }
 503
 504 /*
 505  *      Notify system
 506  */
 507
 508 static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
 509 {
 510         if (code==SYS_DOWN || code==SYS_HALT) {
 511                 /* Turn the WDT off */
 512                 usb_pcwd_stop(usb_pcwd_device);
 513         }
 514
 515         return NOTIFY_DONE;
 516 }
 517
 518 /*
 519  *      Kernel Interfaces
 520  */
 521
 522 static const struct file_operations usb_pcwd_fops = {
 523         .owner =        THIS_MODULE,
 524         .llseek =       no_llseek,
 525         .write =        usb_pcwd_write,
 526         .ioctl =        usb_pcwd_ioctl,
 527         .open =         usb_pcwd_open,
 528         .release =      usb_pcwd_release,
 529 };
 530
 531 static struct miscdevice usb_pcwd_miscdev = {
 532         .minor =        WATCHDOG_MINOR,
 533         .name =         "watchdog",
 534         .fops =         &usb_pcwd_fops,
 535 };
 536
 537 static const struct file_operations usb_pcwd_temperature_fops = {
 538         .owner =        THIS_MODULE,
 539         .llseek =       no_llseek,
 540         .read =         usb_pcwd_temperature_read,
 541         .open =         usb_pcwd_temperature_open,
 542         .release =      usb_pcwd_temperature_release,
 543 };
 544
 545 static struct miscdevice usb_pcwd_temperature_miscdev = {
 546         .minor =        TEMP_MINOR,
 547         .name =         "temperature",
 548         .fops =         &usb_pcwd_temperature_fops,
 549 };
 550
 551 static struct notifier_block usb_pcwd_notifier = {
 552         .notifier_call =        usb_pcwd_notify_sys,
 553 };
 554
 555 /**
 556  *      usb_pcwd_delete
 557  */
 558 static inline void usb_pcwd_delete (struct usb_pcwd_private *usb_pcwd)
 559 {
 560         usb_free_urb(usb_pcwd->intr_urb);
 561         if (usb_pcwd->intr_buffer != NULL)
 562                 usb_buffer_free(usb_pcwd->udev, usb_pcwd->intr_size,
 563                                 usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
 564         kfree (usb_pcwd);
 565 }
 566
 567 /**
 568  *      usb_pcwd_probe
 569  *
 570  *      Called by the usb core when a new device is connected that it thinks
 571  *      this driver might be interested in.
 572  */
 573 static int usb_pcwd_probe(struct usb_interface *interface, const struct usb_device_id *id)
 574 {
 575         struct usb_device *udev = interface_to_usbdev(interface);
 576         struct usb_host_interface *iface_desc;
 577         struct usb_endpoint_descriptor *endpoint;
 578         struct usb_pcwd_private *usb_pcwd = NULL;
 579         int pipe, maxp;
 580         int retval = -ENOMEM;
 581         int got_fw_rev;
 582         unsigned char fw_rev_major, fw_rev_minor;
 583         char fw_ver_str[20];
 584         unsigned char option_switches, dummy;
 585
 586         cards_found++;
 587         if (cards_found > 1) {
 588                 printk(KERN_ERR PFX "This driver only supports 1 device\n");
 589                 return -ENODEV;
 590         }
 591
 592         /* get the active interface descriptor */
 593         iface_desc = interface->cur_altsetting;
 594
 595         /* check out that we have a HID device */
 596         if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
 597                 printk(KERN_ERR PFX "The device isn't a Human Interface Device\n");
 598                 return -ENODEV;
 599         }
 600
 601         /* check out the endpoint: it has to be Interrupt & IN */
 602         endpoint = &iface_desc->endpoint[0].desc;
 603
 604         if (!((endpoint->bEndpointAddress & USB_DIR_IN) &&
 605              ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 606                                 == USB_ENDPOINT_XFER_INT))) {
 607                 /* we didn't find a Interrupt endpoint with direction IN */
 608                 printk(KERN_ERR PFX "Couldn't find an INTR & IN endpoint\n");
 609                 return -ENODEV;
 610         }
 611
 612         /* get a handle to the interrupt data pipe */
 613         pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
 614         maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
 615
 616         /* allocate memory for our device and initialize it */
 617         usb_pcwd = kmalloc (sizeof(struct usb_pcwd_private), GFP_KERNEL);
 618         if (usb_pcwd == NULL) {
 619                 printk(KERN_ERR PFX "Out of memory\n");
 620                 goto error;
 621         }
 622         memset (usb_pcwd, 0x00, sizeof (*usb_pcwd));
 623
 624         usb_pcwd_device = usb_pcwd;
 625
 626         init_MUTEX (&usb_pcwd->sem);
 627         usb_pcwd->udev = udev;
 628         usb_pcwd->interface = interface;
 629         usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
 630         usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ? le16_to_cpu(endpoint->wMaxPacketSize) : 8);
 631
 632         /* set up the memory buffer's */
 633         if (!(usb_pcwd->intr_buffer = usb_buffer_alloc(udev, usb_pcwd->intr_size, GFP_ATOMIC, &usb_pcwd->intr_dma))) {
 634                 printk(KERN_ERR PFX "Out of memory\n");
 635                 goto error;
 636         }
 637
 638         /* allocate the urb's */
 639         usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
 640         if (!usb_pcwd->intr_urb) {
 641                 printk(KERN_ERR PFX "Out of memory\n");
 642                 goto error;
 643         }
 644
 645         /* initialise the intr urb's */
 646         usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
 647                         usb_pcwd->intr_buffer, usb_pcwd->intr_size,
 648                         usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
 649         usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
 650         usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 651
 652         /* register our interrupt URB with the USB system */
 653         if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
 654                 printk(KERN_ERR PFX "Problem registering interrupt URB\n");
 655                 retval = -EIO; /* failure */
 656                 goto error;
 657         }
 658
 659         /* The device exists and can be communicated with */
 660         usb_pcwd->exists = 1;
 661
 662         /* disable card */
 663         usb_pcwd_stop(usb_pcwd);
 664
 665         /* Get the Firmware Version */
 666         got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION, &fw_rev_major, &fw_rev_minor);
 667         if (got_fw_rev) {
 668                 sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
 669         } else {
 670                 sprintf(fw_ver_str, "<card no answer>");
 671         }
 672
 673         printk(KERN_INFO PFX "Found card (Firmware: %s) with temp option\n",
 674                 fw_ver_str);
 675
 676         /* Get switch settings */
 677         usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy, &option_switches);
 678
 679         printk(KERN_INFO PFX "Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
 680                 option_switches,
 681                 ((option_switches & 0x10) ? "ON" : "OFF"),
 682                 ((option_switches & 0x08) ? "ON" : "OFF"));
 683
 684         /* Check that the heartbeat value is within it's range ; if not reset to the default */
 685         if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) {
 686                 usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT);
 687                 printk(KERN_INFO PFX "heartbeat value must be 0<heartbeat<65536, using %d\n",
 688                         WATCHDOG_HEARTBEAT);
 689         }
 690
 691         retval = register_reboot_notifier(&usb_pcwd_notifier);
 692         if (retval != 0) {
 693                 printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
 694                         retval);
 695                 goto error;
 696         }
 697
 698         retval = misc_register(&usb_pcwd_temperature_miscdev);
 699         if (retval != 0) {
 700                 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
 701                         TEMP_MINOR, retval);
 702                 goto err_out_unregister_reboot;
 703         }
 704
 705         retval = misc_register(&usb_pcwd_miscdev);
 706         if (retval != 0) {
 707                 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
 708                         WATCHDOG_MINOR, retval);
 709                 goto err_out_misc_deregister;
 710         }
 711
 712         /* we can register the device now, as it is ready */
 713         usb_set_intfdata (interface, usb_pcwd);
 714
 715         printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
 716                 heartbeat, nowayout);
 717
 718         return 0;
 719
 720 err_out_misc_deregister:
 721         misc_deregister(&usb_pcwd_temperature_miscdev);
 722 err_out_unregister_reboot:
 723         unregister_reboot_notifier(&usb_pcwd_notifier);
 724 error:
 725         if (usb_pcwd)
 726                 usb_pcwd_delete(usb_pcwd);
 727         usb_pcwd_device = NULL;
 728         return retval;
 729 }
 730
 731
 732 /**
 733  *      usb_pcwd_disconnect
 734  *
 735  *      Called by the usb core when the device is removed from the system.
 736  *
 737  *      This routine guarantees that the driver will not submit any more urbs
 738  *      by clearing dev->udev.
 739  */
 740 static void usb_pcwd_disconnect(struct usb_interface *interface)
 741 {
 742         struct usb_pcwd_private *usb_pcwd;
 743
 744         /* prevent races with open() */
 745         mutex_lock(&disconnect_mutex);
 746
 747         usb_pcwd = usb_get_intfdata (interface);
 748         usb_set_intfdata (interface, NULL);
 749
 750         down (&usb_pcwd->sem);
 751
 752         /* Stop the timer before we leave */
 753         if (!nowayout)
 754                 usb_pcwd_stop(usb_pcwd);
 755
 756         /* We should now stop communicating with the USB PCWD device */
 757         usb_pcwd->exists = 0;
 758
 759         /* Deregister */
 760         misc_deregister(&usb_pcwd_miscdev);
 761         misc_deregister(&usb_pcwd_temperature_miscdev);
 762         unregister_reboot_notifier(&usb_pcwd_notifier);
 763
 764         up (&usb_pcwd->sem);
 765
 766         /* Delete the USB PCWD device */
 767         usb_pcwd_delete(usb_pcwd);
 768
 769         cards_found--;
 770
 771         mutex_unlock(&disconnect_mutex);
 772
 773         printk(KERN_INFO PFX "USB PC Watchdog disconnected\n");
 774 }
 775
 776
 777
 778 /**
 779  *      usb_pcwd_init
 780  */
 781 static int __init usb_pcwd_init(void)
 782 {
 783         int result;
 784
 785         /* register this driver with the USB subsystem */
 786         result = usb_register(&usb_pcwd_driver);
 787         if (result) {
 788                 printk(KERN_ERR PFX "usb_register failed. Error number %d\n",
 789                     result);
 790                 return result;
 791         }
 792
 793         printk(KERN_INFO PFX DRIVER_DESC " v" DRIVER_VERSION " (" DRIVER_DATE ")\n");
 794         return 0;
 795 }
 796
 797
 798 /**
 799  *      usb_pcwd_exit
 800  */
 801 static void __exit usb_pcwd_exit(void)
 802 {
 803         /* deregister this driver with the USB subsystem */
 804         usb_deregister(&usb_pcwd_driver);
 805 }
 806
 807
 808 module_init (usb_pcwd_init);
 809 module_exit (usb_pcwd_exit);