linux/drivers/watchdog/pcwd_usb.c
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   1/*
   2 *      Berkshire USB-PC Watchdog Card Driver
   3 *
   4 *      (c) Copyright 2004-2007 Wim Van Sebroeck <wim@iguana.be>.
   5 *
   6 *      Based on source code of the following authors:
   7 *        Ken Hollis <kenji@bitgate.com>,
   8 *        Alan Cox <alan@lxorguk.ukuu.org.uk>,
   9 *        Matt Domsch <Matt_Domsch@dell.com>,
  10 *        Rob Radez <rob@osinvestor.com>,
  11 *        Greg Kroah-Hartman <greg@kroah.com>
  12 *
  13 *      This program is free software; you can redistribute it and/or
  14 *      modify it under the terms of the GNU General Public License
  15 *      as published by the Free Software Foundation; either version
  16 *      2 of the License, or (at your option) any later version.
  17 *
  18 *      Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
  19 *      provide warranty for any of this software. This material is
  20 *      provided "AS-IS" and at no charge.
  21 *
  22 *      Thanks also to Simon Machell at Berkshire Products Inc. for
  23 *      providing the test hardware. More info is available at
  24 *      http://www.berkprod.com/ or http://www.pcwatchdog.com/
  25 */
  26
  27#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#include <linux/uaccess.h>      /* For copy_to_user/put_user/... */
  44
  45
  46#ifdef CONFIG_USB_DEBUG
  47        static int debug = 1;
  48#else
  49        static int debug;
  50#endif
  51
  52/* Use our own dbg macro */
  53#undef dbg
  54#define dbg(format, arg...) do { if (debug) printk(KERN_DEBUG PFX format "\n" , ## arg); } while (0)
  55
  56
  57/* Module and Version Information */
  58#define DRIVER_VERSION "1.02"
  59#define DRIVER_DATE "21 Jan 2007"
  60#define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>"
  61#define DRIVER_DESC "Berkshire USB-PC Watchdog driver"
  62#define DRIVER_LICENSE "GPL"
  63#define DRIVER_NAME "pcwd_usb"
  64#define PFX DRIVER_NAME ": "
  65
  66MODULE_AUTHOR(DRIVER_AUTHOR);
  67MODULE_DESCRIPTION(DRIVER_DESC);
  68MODULE_LICENSE(DRIVER_LICENSE);
  69MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
  70MODULE_ALIAS_MISCDEV(TEMP_MINOR);
  71
  72/* Module Parameters */
  73module_param(debug, int, 0);
  74MODULE_PARM_DESC(debug, "Debug enabled or not");
  75
  76#define WATCHDOG_HEARTBEAT 0    /* default heartbeat = delay-time from dip-switches */
  77static int heartbeat = WATCHDOG_HEARTBEAT;
  78module_param(heartbeat, int, 0);
  79MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (0<heartbeat<65536 or 0=delay-time from dip-switches, default=" __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
  80
  81static int nowayout = WATCHDOG_NOWAYOUT;
  82module_param(nowayout, int, 0);
  83MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
  84
  85/* The vendor and product id's for the USB-PC Watchdog card */
  86#define USB_PCWD_VENDOR_ID      0x0c98
  87#define USB_PCWD_PRODUCT_ID     0x1140
  88
  89/* table of devices that work with this driver */
  90static struct usb_device_id usb_pcwd_table[] = {
  91        { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) },
  92        { }                                     /* Terminating entry */
  93};
  94MODULE_DEVICE_TABLE (usb, usb_pcwd_table);
  95
  96/* according to documentation max. time to process a command for the USB
  97 * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */
  98#define USB_COMMAND_TIMEOUT     250
  99
 100/* Watchdog's internal commands */
 101#define CMD_READ_TEMP                   0x02    /* Read Temperature; Re-trigger Watchdog */
 102#define CMD_TRIGGER                     CMD_READ_TEMP
 103#define CMD_GET_STATUS                  0x04    /* Get Status Information */
 104#define CMD_GET_FIRMWARE_VERSION        0x08    /* Get Firmware Version */
 105#define CMD_GET_DIP_SWITCH_SETTINGS     0x0c    /* Get Dip Switch Settings */
 106#define CMD_READ_WATCHDOG_TIMEOUT       0x18    /* Read Current Watchdog Time */
 107#define CMD_WRITE_WATCHDOG_TIMEOUT      0x19    /* Write Current Watchdog Time */
 108#define CMD_ENABLE_WATCHDOG             0x30    /* Enable / Disable Watchdog */
 109#define CMD_DISABLE_WATCHDOG            CMD_ENABLE_WATCHDOG
 110
 111/* Watchdog's Dip Switch heartbeat values */
 112static const int heartbeat_tbl[] = {
 113        5,      /* OFF-OFF-OFF  =  5 Sec  */
 114        10,     /* OFF-OFF-ON   = 10 Sec  */
 115        30,     /* OFF-ON-OFF   = 30 Sec  */
 116        60,     /* OFF-ON-ON    =  1 Min  */
 117        300,    /* ON-OFF-OFF   =  5 Min  */
 118        600,    /* ON-OFF-ON    = 10 Min  */
 119        1800,   /* ON-ON-OFF    = 30 Min  */
 120        3600,   /* ON-ON-ON     =  1 hour */
 121};
 122
 123/* We can only use 1 card due to the /dev/watchdog restriction */
 124static int cards_found;
 125
 126/* some internal variables */
 127static unsigned long is_active;
 128static char expect_release;
 129
 130/* Structure to hold all of our device specific stuff */
 131struct usb_pcwd_private {
 132        struct usb_device       *udev;                  /* save off the usb device pointer */
 133        struct usb_interface    *interface;             /* the interface for this device */
 134
 135        unsigned int            interface_number;       /* the interface number used for cmd's */
 136
 137        unsigned char           *intr_buffer;           /* the buffer to intr data */
 138        dma_addr_t              intr_dma;               /* the dma address for the intr buffer */
 139        size_t                  intr_size;              /* the size of the intr buffer */
 140        struct urb              *intr_urb;              /* the urb used for the intr pipe */
 141
 142        unsigned char           cmd_command;            /* The command that is reported back */
 143        unsigned char           cmd_data_msb;           /* The data MSB that is reported back */
 144        unsigned char           cmd_data_lsb;           /* The data LSB that is reported back */
 145        atomic_t                cmd_received;           /* true if we received a report after a command */
 146
 147        int                     exists;                 /* Wether or not the device exists */
 148        struct mutex            mtx;                    /* locks this structure */
 149};
 150static struct usb_pcwd_private *usb_pcwd_device;
 151
 152/* prevent races between open() and disconnect() */
 153static DEFINE_MUTEX(disconnect_mutex);
 154
 155/* local function prototypes */
 156static int usb_pcwd_probe(struct usb_interface *interface, const struct usb_device_id *id);
 157static void usb_pcwd_disconnect(struct usb_interface *interface);
 158
 159/* usb specific object needed to register this driver with the usb subsystem */
 160static struct usb_driver usb_pcwd_driver = {
 161        .name =         DRIVER_NAME,
 162        .probe =        usb_pcwd_probe,
 163        .disconnect =   usb_pcwd_disconnect,
 164        .id_table =     usb_pcwd_table,
 165};
 166
 167
 168static void usb_pcwd_intr_done(struct urb *urb)
 169{
 170        struct usb_pcwd_private *usb_pcwd = (struct usb_pcwd_private *)urb->context;
 171        unsigned char *data = usb_pcwd->intr_buffer;
 172        int retval;
 173
 174        switch (urb->status) {
 175        case 0:                 /* success */
 176                break;
 177        case -ECONNRESET:       /* unlink */
 178        case -ENOENT:
 179        case -ESHUTDOWN:
 180                /* this urb is terminated, clean up */
 181                dbg("%s - urb shutting down with status: %d", __func__, urb->status);
 182                return;
 183        /* -EPIPE:  should clear the halt */
 184        default:                /* error */
 185                dbg("%s - nonzero urb status received: %d", __func__, urb->status);
 186                goto resubmit;
 187        }
 188
 189        dbg("received following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
 190                data[0], data[1], data[2]);
 191
 192        usb_pcwd->cmd_command  = data[0];
 193        usb_pcwd->cmd_data_msb = data[1];
 194        usb_pcwd->cmd_data_lsb = data[2];
 195
 196        /* notify anyone waiting that the cmd has finished */
 197        atomic_set(&usb_pcwd->cmd_received, 1);
 198
 199resubmit:
 200        retval = usb_submit_urb(urb, GFP_ATOMIC);
 201        if (retval)
 202                printk(KERN_ERR PFX "can't resubmit intr, usb_submit_urb failed with result %d\n",
 203                        retval);
 204}
 205
 206static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd, unsigned char cmd,
 207        unsigned char *msb, unsigned char *lsb)
 208{
 209        int got_response, count;
 210        unsigned char buf[6];
 211
 212        /* We will not send any commands if the USB PCWD device does not exist */
 213        if ((!usb_pcwd) || (!usb_pcwd->exists))
 214                return -1;
 215
 216        /* The USB PC Watchdog uses a 6 byte report format. The board currently uses
 217         * only 3 of the six bytes of the report. */
 218        buf[0] = cmd;                   /* Byte 0 = CMD */
 219        buf[1] = *msb;                  /* Byte 1 = Data MSB */
 220        buf[2] = *lsb;                  /* Byte 2 = Data LSB */
 221        buf[3] = buf[4] = buf[5] = 0;   /* All other bytes not used */
 222
 223        dbg("sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
 224                buf[0], buf[1], buf[2]);
 225
 226        atomic_set(&usb_pcwd->cmd_received, 0);
 227
 228        if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0),
 229                        HID_REQ_SET_REPORT, HID_DT_REPORT,
 230                        0x0200, usb_pcwd->interface_number, buf, sizeof(buf),
 231                        USB_COMMAND_TIMEOUT) != sizeof(buf)) {
 232                dbg("usb_pcwd_send_command: error in usb_control_msg for cmd 0x%x 0x%x 0x%x\n", cmd, *msb, *lsb);
 233        }
 234        /* wait till the usb card processed the command,
 235         * with a max. timeout of USB_COMMAND_TIMEOUT */
 236        got_response = 0;
 237        for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response); count++) {
 238                mdelay(1);
 239                if (atomic_read(&usb_pcwd->cmd_received))
 240                        got_response = 1;
 241        }
 242
 243        if ((got_response) && (cmd == usb_pcwd->cmd_command)) {
 244                /* read back response */
 245                *msb = usb_pcwd->cmd_data_msb;
 246                *lsb = usb_pcwd->cmd_data_lsb;
 247        }
 248
 249        return got_response;
 250}
 251
 252static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd)
 253{
 254        unsigned char msb = 0x00;
 255        unsigned char lsb = 0x00;
 256        int retval;
 257
 258        /* Enable Watchdog */
 259        retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG, &msb, &lsb);
 260
 261        if ((retval == 0) || (lsb == 0)) {
 262                printk(KERN_ERR PFX "Card did not acknowledge enable attempt\n");
 263                return -1;
 264        }
 265
 266        return 0;
 267}
 268
 269static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd)
 270{
 271        unsigned char msb = 0xA5;
 272        unsigned char lsb = 0xC3;
 273        int retval;
 274
 275        /* Disable Watchdog */
 276        retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG, &msb, &lsb);
 277
 278        if ((retval == 0) || (lsb != 0)) {
 279                printk(KERN_ERR PFX "Card did not acknowledge disable attempt\n");
 280                return -1;
 281        }
 282
 283        return 0;
 284}
 285
 286static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd)
 287{
 288        unsigned char dummy;
 289
 290        /* Re-trigger Watchdog */
 291        usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy);
 292
 293        return 0;
 294}
 295
 296static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t)
 297{
 298        unsigned char msb = t / 256;
 299        unsigned char lsb = t % 256;
 300
 301        if ((t < 0x0001) || (t > 0xFFFF))
 302                return -EINVAL;
 303
 304        /* Write new heartbeat to watchdog */
 305        usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb);
 306
 307        heartbeat = t;
 308        return 0;
 309}
 310
 311static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd, int *temperature)
 312{
 313        unsigned char msb, lsb;
 314
 315        usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb);
 316
 317        /*
 318         * Convert celsius to fahrenheit, since this was
 319         * the decided 'standard' for this return value.
 320         */
 321        *temperature = (lsb * 9 / 5) + 32;
 322
 323        return 0;
 324}
 325
 326static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd, int *time_left)
 327{
 328        unsigned char msb, lsb;
 329
 330        /* Read the time that's left before rebooting */
 331        /* Note: if the board is not yet armed then we will read 0xFFFF */
 332        usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
 333
 334        *time_left = (msb << 8) + lsb;
 335
 336        return 0;
 337}
 338
 339/*
 340 *      /dev/watchdog handling
 341 */
 342
 343static ssize_t usb_pcwd_write(struct file *file, const char __user *data,
 344                              size_t len, loff_t *ppos)
 345{
 346        /* See if we got the magic character 'V' and reload the timer */
 347        if (len) {
 348                if (!nowayout) {
 349                        size_t i;
 350
 351                        /* note: just in case someone wrote the magic character
 352                         * five months ago... */
 353                        expect_release = 0;
 354
 355                        /* scan to see whether or not we got the magic character */
 356                        for (i = 0; i != len; i++) {
 357                                char c;
 358                                if (get_user(c, data + i))
 359                                        return -EFAULT;
 360                                if (c == 'V')
 361                                        expect_release = 42;
 362                        }
 363                }
 364
 365                /* someone wrote to us, we should reload the timer */
 366                usb_pcwd_keepalive(usb_pcwd_device);
 367        }
 368        return len;
 369}
 370
 371static long usb_pcwd_ioctl(struct file *file, unsigned int cmd,
 372                                                unsigned long arg)
 373{
 374        void __user *argp = (void __user *)arg;
 375        int __user *p = argp;
 376        static struct watchdog_info ident = {
 377                .options =              WDIOF_KEEPALIVEPING |
 378                                        WDIOF_SETTIMEOUT |
 379                                        WDIOF_MAGICCLOSE,
 380                .firmware_version =     1,
 381                .identity =             DRIVER_NAME,
 382        };
 383
 384        switch (cmd) {
 385        case WDIOC_GETSUPPORT:
 386                return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
 387
 388        case WDIOC_GETSTATUS:
 389        case WDIOC_GETBOOTSTATUS:
 390                return put_user(0, p);
 391
 392        case WDIOC_GETTEMP:
 393        {
 394                int temperature;
 395
 396                if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
 397                        return -EFAULT;
 398
 399                return put_user(temperature, p);
 400        }
 401
 402        case WDIOC_SETOPTIONS:
 403        {
 404                int new_options, retval = -EINVAL;
 405
 406                if (get_user(new_options, p))
 407                        return -EFAULT;
 408
 409                if (new_options & WDIOS_DISABLECARD) {
 410                        usb_pcwd_stop(usb_pcwd_device);
 411                        retval = 0;
 412                }
 413
 414                if (new_options & WDIOS_ENABLECARD) {
 415                        usb_pcwd_start(usb_pcwd_device);
 416                        retval = 0;
 417                }
 418
 419                return retval;
 420        }
 421
 422        case WDIOC_KEEPALIVE:
 423                usb_pcwd_keepalive(usb_pcwd_device);
 424                return 0;
 425
 426        case WDIOC_SETTIMEOUT:
 427        {
 428                int new_heartbeat;
 429
 430                if (get_user(new_heartbeat, p))
 431                        return -EFAULT;
 432
 433                if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
 434                    return -EINVAL;
 435
 436                usb_pcwd_keepalive(usb_pcwd_device);
 437                /* Fall */
 438        }
 439
 440        case WDIOC_GETTIMEOUT:
 441                return put_user(heartbeat, p);
 442
 443        case WDIOC_GETTIMELEFT:
 444        {
 445                int time_left;
 446
 447                if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left))
 448                        return -EFAULT;
 449
 450                return put_user(time_left, p);
 451        }
 452
 453        default:
 454                return -ENOTTY;
 455        }
 456}
 457
 458static int usb_pcwd_open(struct inode *inode, struct file *file)
 459{
 460        /* /dev/watchdog can only be opened once */
 461        if (test_and_set_bit(0, &is_active))
 462                return -EBUSY;
 463
 464        /* Activate */
 465        usb_pcwd_start(usb_pcwd_device);
 466        usb_pcwd_keepalive(usb_pcwd_device);
 467        return nonseekable_open(inode, file);
 468}
 469
 470static int usb_pcwd_release(struct inode *inode, struct file *file)
 471{
 472        /*
 473         *      Shut off the timer.
 474         */
 475        if (expect_release == 42) {
 476                usb_pcwd_stop(usb_pcwd_device);
 477        } else {
 478                printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
 479                usb_pcwd_keepalive(usb_pcwd_device);
 480        }
 481        expect_release = 0;
 482        clear_bit(0, &is_active);
 483        return 0;
 484}
 485
 486/*
 487 *      /dev/temperature handling
 488 */
 489
 490static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data,
 491                                size_t len, loff_t *ppos)
 492{
 493        int temperature;
 494
 495        if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
 496                return -EFAULT;
 497
 498        if (copy_to_user(data, &temperature, 1))
 499                return -EFAULT;
 500
 501        return 1;
 502}
 503
 504static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
 505{
 506        return nonseekable_open(inode, file);
 507}
 508
 509static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
 510{
 511        return 0;
 512}
 513
 514/*
 515 *      Notify system
 516 */
 517
 518static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
 519{
 520        if (code == SYS_DOWN || code == SYS_HALT)
 521                usb_pcwd_stop(usb_pcwd_device); /* Turn the WDT off */
 522
 523        return NOTIFY_DONE;
 524}
 525
 526/*
 527 *      Kernel Interfaces
 528 */
 529
 530static const struct file_operations usb_pcwd_fops = {
 531        .owner =        THIS_MODULE,
 532        .llseek =       no_llseek,
 533        .write =        usb_pcwd_write,
 534        .unlocked_ioctl = usb_pcwd_ioctl,
 535        .open =         usb_pcwd_open,
 536        .release =      usb_pcwd_release,
 537};
 538
 539static struct miscdevice usb_pcwd_miscdev = {
 540        .minor =        WATCHDOG_MINOR,
 541        .name =         "watchdog",
 542        .fops =         &usb_pcwd_fops,
 543};
 544
 545static const struct file_operations usb_pcwd_temperature_fops = {
 546        .owner =        THIS_MODULE,
 547        .llseek =       no_llseek,
 548        .read =         usb_pcwd_temperature_read,
 549        .open =         usb_pcwd_temperature_open,
 550        .release =      usb_pcwd_temperature_release,
 551};
 552
 553static struct miscdevice usb_pcwd_temperature_miscdev = {
 554        .minor =        TEMP_MINOR,
 555        .name =         "temperature",
 556        .fops =         &usb_pcwd_temperature_fops,
 557};
 558
 559static struct notifier_block usb_pcwd_notifier = {
 560        .notifier_call =        usb_pcwd_notify_sys,
 561};
 562
 563/**
 564 *      usb_pcwd_delete
 565 */
 566static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd)
 567{
 568        usb_free_urb(usb_pcwd->intr_urb);
 569        if (usb_pcwd->intr_buffer != NULL)
 570                usb_buffer_free(usb_pcwd->udev, usb_pcwd->intr_size,
 571                                usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
 572        kfree(usb_pcwd);
 573}
 574
 575/**
 576 *      usb_pcwd_probe
 577 *
 578 *      Called by the usb core when a new device is connected that it thinks
 579 *      this driver might be interested in.
 580 */
 581static int usb_pcwd_probe(struct usb_interface *interface, const struct usb_device_id *id)
 582{
 583        struct usb_device *udev = interface_to_usbdev(interface);
 584        struct usb_host_interface *iface_desc;
 585        struct usb_endpoint_descriptor *endpoint;
 586        struct usb_pcwd_private *usb_pcwd = NULL;
 587        int pipe, maxp;
 588        int retval = -ENOMEM;
 589        int got_fw_rev;
 590        unsigned char fw_rev_major, fw_rev_minor;
 591        char fw_ver_str[20];
 592        unsigned char option_switches, dummy;
 593
 594        cards_found++;
 595        if (cards_found > 1) {
 596                printk(KERN_ERR PFX "This driver only supports 1 device\n");
 597                return -ENODEV;
 598        }
 599
 600        /* get the active interface descriptor */
 601        iface_desc = interface->cur_altsetting;
 602
 603        /* check out that we have a HID device */
 604        if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
 605                printk(KERN_ERR PFX "The device isn't a Human Interface Device\n");
 606                return -ENODEV;
 607        }
 608
 609        /* check out the endpoint: it has to be Interrupt & IN */
 610        endpoint = &iface_desc->endpoint[0].desc;
 611
 612        if (!((endpoint->bEndpointAddress & USB_DIR_IN) &&
 613             ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 614                                == USB_ENDPOINT_XFER_INT))) {
 615                /* we didn't find a Interrupt endpoint with direction IN */
 616                printk(KERN_ERR PFX "Couldn't find an INTR & IN endpoint\n");
 617                return -ENODEV;
 618        }
 619
 620        /* get a handle to the interrupt data pipe */
 621        pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
 622        maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
 623
 624        /* allocate memory for our device and initialize it */
 625        usb_pcwd = kzalloc(sizeof(struct usb_pcwd_private), GFP_KERNEL);
 626        if (usb_pcwd == NULL) {
 627                printk(KERN_ERR PFX "Out of memory\n");
 628                goto error;
 629        }
 630
 631        usb_pcwd_device = usb_pcwd;
 632
 633        mutex_init(&usb_pcwd->mtx);
 634        usb_pcwd->udev = udev;
 635        usb_pcwd->interface = interface;
 636        usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
 637        usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ? le16_to_cpu(endpoint->wMaxPacketSize) : 8);
 638
 639        /* set up the memory buffer's */
 640        usb_pcwd->intr_buffer = usb_buffer_alloc(udev, usb_pcwd->intr_size, GFP_ATOMIC, &usb_pcwd->intr_dma);
 641        if (!usb_pcwd->intr_buffer) {
 642                printk(KERN_ERR PFX "Out of memory\n");
 643                goto error;
 644        }
 645
 646        /* allocate the urb's */
 647        usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
 648        if (!usb_pcwd->intr_urb) {
 649                printk(KERN_ERR PFX "Out of memory\n");
 650                goto error;
 651        }
 652
 653        /* initialise the intr urb's */
 654        usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
 655                        usb_pcwd->intr_buffer, usb_pcwd->intr_size,
 656                        usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
 657        usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
 658        usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 659
 660        /* register our interrupt URB with the USB system */
 661        if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
 662                printk(KERN_ERR PFX "Problem registering interrupt URB\n");
 663                retval = -EIO; /* failure */
 664                goto error;
 665        }
 666
 667        /* The device exists and can be communicated with */
 668        usb_pcwd->exists = 1;
 669
 670        /* disable card */
 671        usb_pcwd_stop(usb_pcwd);
 672
 673        /* Get the Firmware Version */
 674        got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION, &fw_rev_major, &fw_rev_minor);
 675        if (got_fw_rev)
 676                sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
 677        else
 678                sprintf(fw_ver_str, "<card no answer>");
 679
 680        printk(KERN_INFO PFX "Found card (Firmware: %s) with temp option\n",
 681                fw_ver_str);
 682
 683        /* Get switch settings */
 684        usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy, &option_switches);
 685
 686        printk(KERN_INFO PFX "Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
 687                option_switches,
 688                ((option_switches & 0x10) ? "ON" : "OFF"),
 689                ((option_switches & 0x08) ? "ON" : "OFF"));
 690
 691        /* If heartbeat = 0 then we use the heartbeat from the dip-switches */
 692        if (heartbeat == 0)
 693                heartbeat = heartbeat_tbl[(option_switches & 0x07)];
 694
 695        /* Check that the heartbeat value is within it's range ; if not reset to the default */
 696        if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) {
 697                usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT);
 698                printk(KERN_INFO PFX "heartbeat value must be 0<heartbeat<65536, using %d\n",
 699                        WATCHDOG_HEARTBEAT);
 700        }
 701
 702        retval = register_reboot_notifier(&usb_pcwd_notifier);
 703        if (retval != 0) {
 704                printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
 705                        retval);
 706                goto error;
 707        }
 708
 709        retval = misc_register(&usb_pcwd_temperature_miscdev);
 710        if (retval != 0) {
 711                printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
 712                        TEMP_MINOR, retval);
 713                goto err_out_unregister_reboot;
 714        }
 715
 716        retval = misc_register(&usb_pcwd_miscdev);
 717        if (retval != 0) {
 718                printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
 719                        WATCHDOG_MINOR, retval);
 720                goto err_out_misc_deregister;
 721        }
 722
 723        /* we can register the device now, as it is ready */
 724        usb_set_intfdata(interface, usb_pcwd);
 725
 726        printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
 727                heartbeat, nowayout);
 728
 729        return 0;
 730
 731err_out_misc_deregister:
 732        misc_deregister(&usb_pcwd_temperature_miscdev);
 733err_out_unregister_reboot:
 734        unregister_reboot_notifier(&usb_pcwd_notifier);
 735error:
 736        if (usb_pcwd)
 737                usb_pcwd_delete(usb_pcwd);
 738        usb_pcwd_device = NULL;
 739        return retval;
 740}
 741
 742
 743/**
 744 *      usb_pcwd_disconnect
 745 *
 746 *      Called by the usb core when the device is removed from the system.
 747 *
 748 *      This routine guarantees that the driver will not submit any more urbs
 749 *      by clearing dev->udev.
 750 */
 751static void usb_pcwd_disconnect(struct usb_interface *interface)
 752{
 753        struct usb_pcwd_private *usb_pcwd;
 754
 755        /* prevent races with open() */
 756        mutex_lock(&disconnect_mutex);
 757
 758        usb_pcwd = usb_get_intfdata(interface);
 759        usb_set_intfdata(interface, NULL);
 760
 761        mutex_lock(&usb_pcwd->mtx);
 762
 763        /* Stop the timer before we leave */
 764        if (!nowayout)
 765                usb_pcwd_stop(usb_pcwd);
 766
 767        /* We should now stop communicating with the USB PCWD device */
 768        usb_pcwd->exists = 0;
 769
 770        /* Deregister */
 771        misc_deregister(&usb_pcwd_miscdev);
 772        misc_deregister(&usb_pcwd_temperature_miscdev);
 773        unregister_reboot_notifier(&usb_pcwd_notifier);
 774
 775        mutex_unlock(&usb_pcwd->mtx);
 776
 777        /* Delete the USB PCWD device */
 778        usb_pcwd_delete(usb_pcwd);
 779
 780        cards_found--;
 781
 782        mutex_unlock(&disconnect_mutex);
 783
 784        printk(KERN_INFO PFX "USB PC Watchdog disconnected\n");
 785}
 786
 787
 788
 789/**
 790 *      usb_pcwd_init
 791 */
 792static int __init usb_pcwd_init(void)
 793{
 794        int result;
 795
 796        /* register this driver with the USB subsystem */
 797        result = usb_register(&usb_pcwd_driver);
 798        if (result) {
 799                printk(KERN_ERR PFX "usb_register failed. Error number %d\n",
 800                    result);
 801                return result;
 802        }
 803
 804        printk(KERN_INFO PFX DRIVER_DESC " v" DRIVER_VERSION " (" DRIVER_DATE ")\n");
 805        return 0;
 806}
 807
 808
 809/**
 810 *      usb_pcwd_exit
 811 */
 812static void __exit usb_pcwd_exit(void)
 813{
 814        /* deregister this driver with the USB subsystem */
 815        usb_deregister(&usb_pcwd_driver);
 816}
 817
 818
 819module_init(usb_pcwd_init);
 820module_exit(usb_pcwd_exit);
 821