git.oblomov.eu Git - linux-2.6/blob - 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/config.h>
  28 #include <linux/kernel.h>
  29 #include <linux/errno.h>
  30 #include <linux/init.h>
  31 #include <linux/slab.h>
  32 #include <linux/module.h>
  33 #include <linux/moduleparam.h>
  34 #include <linux/types.h>
  35 #include <linux/delay.h>
  36 #include <linux/miscdevice.h>
  37 #include <linux/watchdog.h>
  38 #include <linux/notifier.h>
  39 #include <linux/reboot.h>
  40 #include <linux/fs.h>
  41 #include <linux/smp_lock.h>
  42 #include <linux/completion.h>
  43 #include <asm/uaccess.h>
  44 #include <linux/usb.h>
  45 #include <linux/mutex.h>
  46
  47
  48 #ifdef CONFIG_USB_DEBUG
  49         static int debug = 1;
  50 #else
  51         static int debug;
  52 #endif
  53
  54 /* Use our own dbg macro */
  55 #undef dbg
  56 #define dbg(format, arg...) do { if (debug) printk(KERN_DEBUG PFX format "\n" , ## arg); } while (0)
  57
  58
  59 /* Module and Version Information */
  60 #define DRIVER_VERSION "1.01"
  61 #define DRIVER_DATE "15 Mar 2005"
  62 #define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>"
  63 #define DRIVER_DESC "Berkshire USB-PC Watchdog driver"
  64 #define DRIVER_LICENSE "GPL"
  65 #define DRIVER_NAME "pcwd_usb"
  66 #define PFX DRIVER_NAME ": "
  67
  68 MODULE_AUTHOR(DRIVER_AUTHOR);
  69 MODULE_DESCRIPTION(DRIVER_DESC);
  70 MODULE_LICENSE(DRIVER_LICENSE);
  71 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
  72 MODULE_ALIAS_MISCDEV(TEMP_MINOR);
  73
  74 /* Module Parameters */
  75 module_param(debug, int, 0);
  76 MODULE_PARM_DESC(debug, "Debug enabled or not");
  77
  78 #define WATCHDOG_HEARTBEAT 2    /* 2 sec default heartbeat */
  79 static int heartbeat = WATCHDOG_HEARTBEAT;
  80 module_param(heartbeat, int, 0);
  81 MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (0<heartbeat<65536, default=" __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
  82
  83 static int nowayout = WATCHDOG_NOWAYOUT;
  84 module_param(nowayout, int, 0);
  85 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
  86
  87 /* The vendor and product id's for the USB-PC Watchdog card */
  88 #define USB_PCWD_VENDOR_ID      0x0c98
  89 #define USB_PCWD_PRODUCT_ID     0x1140
  90
  91 /* table of devices that work with this driver */
  92 static struct usb_device_id usb_pcwd_table [] = {
  93         { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) },
  94         { }                                     /* Terminating entry */
  95 };
  96 MODULE_DEVICE_TABLE (usb, usb_pcwd_table);
  97
  98 /* according to documentation max. time to process a command for the USB
  99  * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */
 100 #define USB_COMMAND_TIMEOUT     250
 101
 102 /* Watchdog's internal commands */
 103 #define CMD_READ_TEMP                   0x02    /* Read Temperature; Re-trigger Watchdog */
 104 #define CMD_TRIGGER                     CMD_READ_TEMP
 105 #define CMD_GET_STATUS                  0x04    /* Get Status Information */
 106 #define CMD_GET_FIRMWARE_VERSION        0x08    /* Get Firmware Version */
 107 #define CMD_GET_DIP_SWITCH_SETTINGS     0x0c    /* Get Dip Switch Settings */
 108 #define CMD_READ_WATCHDOG_TIMEOUT       0x18    /* Read Current Watchdog Time */
 109 #define CMD_WRITE_WATCHDOG_TIMEOUT      0x19    /* Write Current Watchdog Time */
 110 #define CMD_ENABLE_WATCHDOG             0x30    /* Enable / Disable Watchdog */
 111 #define CMD_DISABLE_WATCHDOG            CMD_ENABLE_WATCHDOG
 112
 113 /* Some defines that I like to be somewhere else like include/linux/usb_hid.h */
 114 #define HID_REQ_SET_REPORT              0x09
 115 #define HID_DT_REPORT                   (USB_TYPE_CLASS | 0x02)
 116
 117 /* We can only use 1 card due to the /dev/watchdog restriction */
 118 static int cards_found;
 119
 120 /* some internal variables */
 121 static unsigned long is_active;
 122 static char expect_release;
 123
 124 /* Structure to hold all of our device specific stuff */
 125 struct usb_pcwd_private {
 126         struct usb_device *     udev;                   /* save off the usb device pointer */
 127         struct usb_interface *  interface;              /* the interface for this device */
 128
 129         unsigned int            interface_number;       /* the interface number used for cmd's */
 130
 131         unsigned char *         intr_buffer;            /* the buffer to intr data */
 132         dma_addr_t              intr_dma;               /* the dma address for the intr buffer */
 133         size_t                  intr_size;              /* the size of the intr buffer */
 134         struct urb *            intr_urb;               /* the urb used for the intr pipe */
 135
 136         unsigned char           cmd_command;            /* The command that is reported back */
 137         unsigned char           cmd_data_msb;           /* The data MSB that is reported back */
 138         unsigned char           cmd_data_lsb;           /* The data LSB that is reported back */
 139         atomic_t                cmd_received;           /* true if we received a report after a command */
 140
 141         int                     exists;                 /* Wether or not the device exists */
 142         struct semaphore        sem;                    /* locks this structure */
 143 };
 144 static struct usb_pcwd_private *usb_pcwd_device;
 145
 146 /* prevent races between open() and disconnect() */
 147 static DEFINE_MUTEX(disconnect_mutex);
 148
 149 /* local function prototypes */
 150 static int usb_pcwd_probe       (struct usb_interface *interface, const struct usb_device_id *id);
 151 static void usb_pcwd_disconnect (struct usb_interface *interface);
 152
 153 /* usb specific object needed to register this driver with the usb subsystem */
 154 static struct usb_driver usb_pcwd_driver = {
 155         .name =         DRIVER_NAME,
 156         .probe =        usb_pcwd_probe,
 157         .disconnect =   usb_pcwd_disconnect,
 158         .id_table =     usb_pcwd_table,
 159 };
 160
 161
 162 static void usb_pcwd_intr_done(struct urb *urb, struct pt_regs *regs)
 163 {
 164         struct usb_pcwd_private *usb_pcwd = (struct usb_pcwd_private *)urb->context;
 165         unsigned char *data = usb_pcwd->intr_buffer;
 166         int retval;
 167
 168         switch (urb->status) {
 169         case 0:                 /* success */
 170                 break;
 171         case -ECONNRESET:       /* unlink */
 172         case -ENOENT:
 173         case -ESHUTDOWN:
 174                 /* this urb is terminated, clean up */
 175                 dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
 176                 return;
 177         /* -EPIPE:  should clear the halt */
 178         default:                /* error */
 179                 dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
 180                 goto resubmit;
 181         }
 182
 183         dbg("received following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
 184                 data[0], data[1], data[2]);
 185
 186         usb_pcwd->cmd_command  = data[0];
 187         usb_pcwd->cmd_data_msb = data[1];
 188         usb_pcwd->cmd_data_lsb = data[2];
 189
 190         /* notify anyone waiting that the cmd has finished */
 191         atomic_set (&usb_pcwd->cmd_received, 1);
 192
 193 resubmit:
 194         retval = usb_submit_urb (urb, GFP_ATOMIC);
 195         if (retval)
 196                 printk(KERN_ERR PFX "can't resubmit intr, usb_submit_urb failed with result %d\n",
 197                         retval);
 198 }
 199
 200 static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd, unsigned char cmd,
 201         unsigned char *msb, unsigned char *lsb)
 202 {
 203         int got_response, count;
 204         unsigned char buf[6];
 205
 206         /* We will not send any commands if the USB PCWD device does not exist */
 207         if ((!usb_pcwd) || (!usb_pcwd->exists))
 208                 return -1;
 209
 210         /* The USB PC Watchdog uses a 6 byte report format. The board currently uses
 211          * only 3 of the six bytes of the report. */
 212         buf[0] = cmd;                   /* Byte 0 = CMD */
 213         buf[1] = *msb;                  /* Byte 1 = Data MSB */
 214         buf[2] = *lsb;                  /* Byte 2 = Data LSB */
 215         buf[3] = buf[4] = buf[5] = 0;   /* All other bytes not used */
 216
 217         dbg("sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
 218                 buf[0], buf[1], buf[2]);
 219
 220         atomic_set (&usb_pcwd->cmd_received, 0);
 221
 222         if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0),
 223                         HID_REQ_SET_REPORT, HID_DT_REPORT,
 224                         0x0200, usb_pcwd->interface_number, buf, sizeof(buf),
 225                         USB_COMMAND_TIMEOUT) != sizeof(buf)) {
 226                 dbg("usb_pcwd_send_command: error in usb_control_msg for cmd 0x%x 0x%x 0x%x\n", cmd, *msb, *lsb);
 227         }
 228         /* wait till the usb card processed the command,
 229          * with a max. timeout of USB_COMMAND_TIMEOUT */
 230         got_response = 0;
 231         for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response); count++) {
 232                 mdelay(1);
 233                 if (atomic_read (&usb_pcwd->cmd_received))
 234                         got_response = 1;
 235         }
 236
 237         if ((got_response) && (cmd == usb_pcwd->cmd_command)) {
 238                 /* read back response */
 239                 *msb = usb_pcwd->cmd_data_msb;
 240                 *lsb = usb_pcwd->cmd_data_lsb;
 241         }
 242
 243         return got_response;
 244 }
 245
 246 static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd)
 247 {
 248         unsigned char msb = 0x00;
 249         unsigned char lsb = 0x00;
 250         int retval;
 251
 252         /* Enable Watchdog */
 253         retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG, &msb, &lsb);
 254
 255         if ((retval == 0) || (lsb == 0)) {
 256                 printk(KERN_ERR PFX "Card did not acknowledge enable attempt\n");
 257                 return -1;
 258         }
 259
 260         return 0;
 261 }
 262
 263 static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd)
 264 {
 265         unsigned char msb = 0xA5;
 266         unsigned char lsb = 0xC3;
 267         int retval;
 268
 269         /* Disable Watchdog */
 270         retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG, &msb, &lsb);
 271
 272         if ((retval == 0) || (lsb != 0)) {
 273                 printk(KERN_ERR PFX "Card did not acknowledge disable attempt\n");
 274                 return -1;
 275         }
 276
 277         return 0;
 278 }
 279
 280 static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd)
 281 {
 282         unsigned char dummy;
 283
 284         /* Re-trigger Watchdog */
 285         usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy);
 286
 287         return 0;
 288 }
 289
 290 static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t)
 291 {
 292         unsigned char msb = t / 256;
 293         unsigned char lsb = t % 256;
 294
 295         if ((t < 0x0001) || (t > 0xFFFF))
 296                 return -EINVAL;
 297
 298         /* Write new heartbeat to watchdog */
 299         usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb);
 300
 301         heartbeat = t;
 302         return 0;
 303 }
 304
 305 static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd, int *temperature)
 306 {
 307         unsigned char msb, lsb;
 308
 309         usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb);
 310
 311         /*
 312          * Convert celsius to fahrenheit, since this was
 313          * the decided 'standard' for this return value.
 314          */
 315         *temperature = (lsb * 9 / 5) + 32;
 316
 317         return 0;
 318 }
 319
 320 /*
 321  *      /dev/watchdog handling
 322  */
 323
 324 static ssize_t usb_pcwd_write(struct file *file, const char __user *data,
 325                               size_t len, loff_t *ppos)
 326 {
 327         /* See if we got the magic character 'V' and reload the timer */
 328         if (len) {
 329                 if (!nowayout) {
 330                         size_t i;
 331
 332                         /* note: just in case someone wrote the magic character
 333                          * five months ago... */
 334                         expect_release = 0;
 335
 336                         /* scan to see whether or not we got the magic character */
 337                         for (i = 0; i != len; i++) {
 338                                 char c;
 339                                 if(get_user(c, data+i))
 340                                         return -EFAULT;
 341                                 if (c == 'V')
 342                                         expect_release = 42;
 343                         }
 344                 }
 345
 346                 /* someone wrote to us, we should reload the timer */
 347                 usb_pcwd_keepalive(usb_pcwd_device);
 348         }
 349         return len;
 350 }
 351
 352 static int usb_pcwd_ioctl(struct inode *inode, struct file *file,
 353                           unsigned int cmd, unsigned long arg)
 354 {
 355         void __user *argp = (void __user *)arg;
 356         int __user *p = argp;
 357         static struct watchdog_info ident = {
 358                 .options =              WDIOF_KEEPALIVEPING |
 359                                         WDIOF_SETTIMEOUT |
 360                                         WDIOF_MAGICCLOSE,
 361                 .firmware_version =     1,
 362                 .identity =             DRIVER_NAME,
 363         };
 364
 365         switch (cmd) {
 366                 case WDIOC_GETSUPPORT:
 367                         return copy_to_user(argp, &ident,
 368                                 sizeof (ident)) ? -EFAULT : 0;
 369
 370                 case WDIOC_GETSTATUS:
 371                 case WDIOC_GETBOOTSTATUS:
 372                         return put_user(0, p);
 373
 374                 case WDIOC_GETTEMP:
 375                 {
 376                         int temperature;
 377
 378                         if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
 379                                 return -EFAULT;
 380
 381                         return put_user(temperature, p);
 382                 }
 383
 384                 case WDIOC_KEEPALIVE:
 385                         usb_pcwd_keepalive(usb_pcwd_device);
 386                         return 0;
 387
 388                 case WDIOC_SETOPTIONS:
 389                 {
 390                         int new_options, retval = -EINVAL;
 391
 392                         if (get_user (new_options, p))
 393                                 return -EFAULT;
 394
 395                         if (new_options & WDIOS_DISABLECARD) {
 396                                 usb_pcwd_stop(usb_pcwd_device);
 397                                 retval = 0;
 398                         }
 399
 400                         if (new_options & WDIOS_ENABLECARD) {
 401                                 usb_pcwd_start(usb_pcwd_device);
 402                                 retval = 0;
 403                         }
 404
 405                         return retval;
 406                 }
 407
 408                 case WDIOC_SETTIMEOUT:
 409                 {
 410                         int new_heartbeat;
 411
 412                         if (get_user(new_heartbeat, p))
 413                                 return -EFAULT;
 414
 415                         if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
 416                             return -EINVAL;
 417
 418                         usb_pcwd_keepalive(usb_pcwd_device);
 419                         /* Fall */
 420                 }
 421
 422                 case WDIOC_GETTIMEOUT:
 423                         return put_user(heartbeat, p);
 424
 425                 default:
 426                         return -ENOIOCTLCMD;
 427         }
 428 }
 429
 430 static int usb_pcwd_open(struct inode *inode, struct file *file)
 431 {
 432         /* /dev/watchdog can only be opened once */
 433         if (test_and_set_bit(0, &is_active))
 434                 return -EBUSY;
 435
 436         /* Activate */
 437         usb_pcwd_start(usb_pcwd_device);
 438         usb_pcwd_keepalive(usb_pcwd_device);
 439         return nonseekable_open(inode, file);
 440 }
 441
 442 static int usb_pcwd_release(struct inode *inode, struct file *file)
 443 {
 444         /*
 445          *      Shut off the timer.
 446          */
 447         if (expect_release == 42) {
 448                 usb_pcwd_stop(usb_pcwd_device);
 449         } else {
 450                 printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
 451                 usb_pcwd_keepalive(usb_pcwd_device);
 452         }
 453         expect_release = 0;
 454         clear_bit(0, &is_active);
 455         return 0;
 456 }
 457
 458 /*
 459  *      /dev/temperature handling
 460  */
 461
 462 static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data,
 463                                 size_t len, loff_t *ppos)
 464 {
 465         int temperature;
 466
 467         if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
 468                 return -EFAULT;
 469
 470         if (copy_to_user(data, &temperature, 1))
 471                 return -EFAULT;
 472
 473         return 1;
 474 }
 475
 476 static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
 477 {
 478         return nonseekable_open(inode, file);
 479 }
 480
 481 static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
 482 {
 483         return 0;
 484 }
 485
 486 /*
 487  *      Notify system
 488  */
 489
 490 static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
 491 {
 492         if (code==SYS_DOWN || code==SYS_HALT) {
 493                 /* Turn the WDT off */
 494                 usb_pcwd_stop(usb_pcwd_device);
 495         }
 496
 497         return NOTIFY_DONE;
 498 }
 499
 500 /*
 501  *      Kernel Interfaces
 502  */
 503
 504 static struct file_operations usb_pcwd_fops = {
 505         .owner =        THIS_MODULE,
 506         .llseek =       no_llseek,
 507         .write =        usb_pcwd_write,
 508         .ioctl =        usb_pcwd_ioctl,
 509         .open =         usb_pcwd_open,
 510         .release =      usb_pcwd_release,
 511 };
 512
 513 static struct miscdevice usb_pcwd_miscdev = {
 514         .minor =        WATCHDOG_MINOR,
 515         .name =         "watchdog",
 516         .fops =         &usb_pcwd_fops,
 517 };
 518
 519 static struct file_operations usb_pcwd_temperature_fops = {
 520         .owner =        THIS_MODULE,
 521         .llseek =       no_llseek,
 522         .read =         usb_pcwd_temperature_read,
 523         .open =         usb_pcwd_temperature_open,
 524         .release =      usb_pcwd_temperature_release,
 525 };
 526
 527 static struct miscdevice usb_pcwd_temperature_miscdev = {
 528         .minor =        TEMP_MINOR,
 529         .name =         "temperature",
 530         .fops =         &usb_pcwd_temperature_fops,
 531 };
 532
 533 static struct notifier_block usb_pcwd_notifier = {
 534         .notifier_call =        usb_pcwd_notify_sys,
 535 };
 536
 537 /**
 538  *      usb_pcwd_delete
 539  */
 540 static inline void usb_pcwd_delete (struct usb_pcwd_private *usb_pcwd)
 541 {
 542         if (usb_pcwd->intr_urb != NULL)
 543                 usb_free_urb (usb_pcwd->intr_urb);
 544         if (usb_pcwd->intr_buffer != NULL)
 545                 usb_buffer_free(usb_pcwd->udev, usb_pcwd->intr_size,
 546                                 usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
 547         kfree (usb_pcwd);
 548 }
 549
 550 /**
 551  *      usb_pcwd_probe
 552  *
 553  *      Called by the usb core when a new device is connected that it thinks
 554  *      this driver might be interested in.
 555  */
 556 static int usb_pcwd_probe(struct usb_interface *interface, const struct usb_device_id *id)
 557 {
 558         struct usb_device *udev = interface_to_usbdev(interface);
 559         struct usb_host_interface *iface_desc;
 560         struct usb_endpoint_descriptor *endpoint;
 561         struct usb_pcwd_private *usb_pcwd = NULL;
 562         int pipe, maxp;
 563         int retval = -ENOMEM;
 564         int got_fw_rev;
 565         unsigned char fw_rev_major, fw_rev_minor;
 566         char fw_ver_str[20];
 567         unsigned char option_switches, dummy;
 568
 569         cards_found++;
 570         if (cards_found > 1) {
 571                 printk(KERN_ERR PFX "This driver only supports 1 device\n");
 572                 return -ENODEV;
 573         }
 574
 575         /* get the active interface descriptor */
 576         iface_desc = interface->cur_altsetting;
 577
 578         /* check out that we have a HID device */
 579         if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
 580                 printk(KERN_ERR PFX "The device isn't a Human Interface Device\n");
 581                 return -ENODEV;
 582         }
 583
 584         /* check out the endpoint: it has to be Interrupt & IN */
 585         endpoint = &iface_desc->endpoint[0].desc;
 586
 587         if (!((endpoint->bEndpointAddress & USB_DIR_IN) &&
 588              ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 589                                 == USB_ENDPOINT_XFER_INT))) {
 590                 /* we didn't find a Interrupt endpoint with direction IN */
 591                 printk(KERN_ERR PFX "Couldn't find an INTR & IN endpoint\n");
 592                 return -ENODEV;
 593         }
 594
 595         /* get a handle to the interrupt data pipe */
 596         pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
 597         maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
 598
 599         /* allocate memory for our device and initialize it */
 600         usb_pcwd = kmalloc (sizeof(struct usb_pcwd_private), GFP_KERNEL);
 601         if (usb_pcwd == NULL) {
 602                 printk(KERN_ERR PFX "Out of memory\n");
 603                 goto error;
 604         }
 605         memset (usb_pcwd, 0x00, sizeof (*usb_pcwd));
 606
 607         usb_pcwd_device = usb_pcwd;
 608
 609         init_MUTEX (&usb_pcwd->sem);
 610         usb_pcwd->udev = udev;
 611         usb_pcwd->interface = interface;
 612         usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
 613         usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ? le16_to_cpu(endpoint->wMaxPacketSize) : 8);
 614
 615         /* set up the memory buffer's */
 616         if (!(usb_pcwd->intr_buffer = usb_buffer_alloc(udev, usb_pcwd->intr_size, SLAB_ATOMIC, &usb_pcwd->intr_dma))) {
 617                 printk(KERN_ERR PFX "Out of memory\n");
 618                 goto error;
 619         }
 620
 621         /* allocate the urb's */
 622         usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
 623         if (!usb_pcwd->intr_urb) {
 624                 printk(KERN_ERR PFX "Out of memory\n");
 625                 goto error;
 626         }
 627
 628         /* initialise the intr urb's */
 629         usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
 630                         usb_pcwd->intr_buffer, usb_pcwd->intr_size,
 631                         usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
 632         usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
 633         usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 634
 635         /* register our interrupt URB with the USB system */
 636         if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
 637                 printk(KERN_ERR PFX "Problem registering interrupt URB\n");
 638                 retval = -EIO; /* failure */
 639                 goto error;
 640         }
 641
 642         /* The device exists and can be communicated with */
 643         usb_pcwd->exists = 1;
 644
 645         /* disable card */
 646         usb_pcwd_stop(usb_pcwd);
 647
 648         /* Get the Firmware Version */
 649         got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION, &fw_rev_major, &fw_rev_minor);
 650         if (got_fw_rev) {
 651                 sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
 652         } else {
 653                 sprintf(fw_ver_str, "<card no answer>");
 654         }
 655
 656         printk(KERN_INFO PFX "Found card (Firmware: %s) with temp option\n",
 657                 fw_ver_str);
 658
 659         /* Get switch settings */
 660         usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy, &option_switches);
 661
 662         printk(KERN_INFO PFX "Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
 663                 option_switches,
 664                 ((option_switches & 0x10) ? "ON" : "OFF"),
 665                 ((option_switches & 0x08) ? "ON" : "OFF"));
 666
 667         /* Check that the heartbeat value is within it's range ; if not reset to the default */
 668         if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) {
 669                 usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT);
 670                 printk(KERN_INFO PFX "heartbeat value must be 0<heartbeat<65536, using %d\n",
 671                         WATCHDOG_HEARTBEAT);
 672         }
 673
 674         retval = register_reboot_notifier(&usb_pcwd_notifier);
 675         if (retval != 0) {
 676                 printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
 677                         retval);
 678                 goto error;
 679         }
 680
 681         retval = misc_register(&usb_pcwd_temperature_miscdev);
 682         if (retval != 0) {
 683                 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
 684                         TEMP_MINOR, retval);
 685                 goto err_out_unregister_reboot;
 686         }
 687
 688         retval = misc_register(&usb_pcwd_miscdev);
 689         if (retval != 0) {
 690                 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
 691                         WATCHDOG_MINOR, retval);
 692                 goto err_out_misc_deregister;
 693         }
 694
 695         /* we can register the device now, as it is ready */
 696         usb_set_intfdata (interface, usb_pcwd);
 697
 698         printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
 699                 heartbeat, nowayout);
 700
 701         return 0;
 702
 703 err_out_misc_deregister:
 704         misc_deregister(&usb_pcwd_temperature_miscdev);
 705 err_out_unregister_reboot:
 706         unregister_reboot_notifier(&usb_pcwd_notifier);
 707 error:
 708         if (usb_pcwd)
 709                 usb_pcwd_delete(usb_pcwd);
 710         usb_pcwd_device = NULL;
 711         return retval;
 712 }
 713
 714
 715 /**
 716  *      usb_pcwd_disconnect
 717  *
 718  *      Called by the usb core when the device is removed from the system.
 719  *
 720  *      This routine guarantees that the driver will not submit any more urbs
 721  *      by clearing dev->udev.
 722  */
 723 static void usb_pcwd_disconnect(struct usb_interface *interface)
 724 {
 725         struct usb_pcwd_private *usb_pcwd;
 726
 727         /* prevent races with open() */
 728         mutex_lock(&disconnect_mutex);
 729
 730         usb_pcwd = usb_get_intfdata (interface);
 731         usb_set_intfdata (interface, NULL);
 732
 733         down (&usb_pcwd->sem);
 734
 735         /* Stop the timer before we leave */
 736         if (!nowayout)
 737                 usb_pcwd_stop(usb_pcwd);
 738
 739         /* We should now stop communicating with the USB PCWD device */
 740         usb_pcwd->exists = 0;
 741
 742         /* Deregister */
 743         misc_deregister(&usb_pcwd_miscdev);
 744         misc_deregister(&usb_pcwd_temperature_miscdev);
 745         unregister_reboot_notifier(&usb_pcwd_notifier);
 746
 747         up (&usb_pcwd->sem);
 748
 749         /* Delete the USB PCWD device */
 750         usb_pcwd_delete(usb_pcwd);
 751
 752         cards_found--;
 753
 754         mutex_unlock(&disconnect_mutex);
 755
 756         printk(KERN_INFO PFX "USB PC Watchdog disconnected\n");
 757 }
 758
 759
 760
 761 /**
 762  *      usb_pcwd_init
 763  */
 764 static int __init usb_pcwd_init(void)
 765 {
 766         int result;
 767
 768         /* register this driver with the USB subsystem */
 769         result = usb_register(&usb_pcwd_driver);
 770         if (result) {
 771                 printk(KERN_ERR PFX "usb_register failed. Error number %d\n",
 772                     result);
 773                 return result;
 774         }
 775
 776         printk(KERN_INFO PFX DRIVER_DESC " v" DRIVER_VERSION " (" DRIVER_DATE ")\n");
 777         return 0;
 778 }
 779
 780
 781 /**
 782  *      usb_pcwd_exit
 783  */
 784 static void __exit usb_pcwd_exit(void)
 785 {
 786         /* deregister this driver with the USB subsystem */
 787         usb_deregister(&usb_pcwd_driver);
 788 }
 789
 790
 791 module_init (usb_pcwd_init);
 792 module_exit (usb_pcwd_exit);