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