linux/drivers/watchdog/pcwd.c
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   1/*
   2 * PC Watchdog Driver
   3 * by Ken Hollis (khollis@bitgate.com)
   4 *
   5 * Permission granted from Simon Machell (smachell@berkprod.com)
   6 * Written for the Linux Kernel, and GPLed by Ken Hollis
   7 *
   8 * 960107       Added request_region routines, modulized the whole thing.
   9 * 960108       Fixed end-of-file pointer (Thanks to Dan Hollis), added
  10 *              WD_TIMEOUT define.
  11 * 960216       Added eof marker on the file, and changed verbose messages.
  12 * 960716       Made functional and cosmetic changes to the source for
  13 *              inclusion in Linux 2.0.x kernels, thanks to Alan Cox.
  14 * 960717       Removed read/seek routines, replaced with ioctl.  Also, added
  15 *              check_region command due to Alan's suggestion.
  16 * 960821       Made changes to compile in newer 2.0.x kernels.  Added
  17 *              "cold reboot sense" entry.
  18 * 960825       Made a few changes to code, deleted some defines and made
  19 *              typedefs to replace them.  Made heartbeat reset only available
  20 *              via ioctl, and removed the write routine.
  21 * 960828       Added new items for PC Watchdog Rev.C card.
  22 * 960829       Changed around all of the IOCTLs, added new features,
  23 *              added watchdog disable/re-enable routines.  Added firmware
  24 *              version reporting.  Added read routine for temperature.
  25 *              Removed some extra defines, added an autodetect Revision
  26 *              routine.
  27 * 961006       Revised some documentation, fixed some cosmetic bugs.  Made
  28 *              drivers to panic the system if it's overheating at bootup.
  29 * 961118       Changed some verbiage on some of the output, tidied up
  30 *              code bits, and added compatibility to 2.1.x.
  31 * 970912       Enabled board on open and disable on close.
  32 * 971107       Took account of recent VFS changes (broke read).
  33 * 971210       Disable board on initialisation in case board already ticking.
  34 * 971222       Changed open/close for temperature handling
  35 *              Michael Meskes <meskes@debian.org>.
  36 * 980112       Used minor numbers from include/linux/miscdevice.h
  37 * 990403       Clear reset status after reading control status register in
  38 *              pcwd_showprevstate(). [Marc Boucher <marc@mbsi.ca>]
  39 * 990605       Made changes to code to support Firmware 1.22a, added
  40 *              fairly useless proc entry.
  41 * 990610       removed said useless proc code for the merge <alan>
  42 * 000403       Removed last traces of proc code. <davej>
  43 * 011214       Added nowayout module option to override
  44 *              CONFIG_WATCHDOG_NOWAYOUT <Matt_Domsch@dell.com>
  45 *              Added timeout module option to override default
  46 */
  47
  48/*
  49 *      A bells and whistles driver is available from http://www.pcwd.de/
  50 *      More info available at http://www.berkprod.com/ or
  51 *      http://www.pcwatchdog.com/
  52 */
  53
  54#include <linux/module.h>       /* For module specific items */
  55#include <linux/moduleparam.h>  /* For new moduleparam's */
  56#include <linux/types.h>        /* For standard types (like size_t) */
  57#include <linux/errno.h>        /* For the -ENODEV/... values */
  58#include <linux/kernel.h>       /* For printk/panic/... */
  59#include <linux/delay.h>        /* For mdelay function */
  60#include <linux/timer.h>        /* For timer related operations */
  61#include <linux/jiffies.h>      /* For jiffies stuff */
  62#include <linux/miscdevice.h>   /* For MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR) */
  63#include <linux/watchdog.h>     /* For the watchdog specific items */
  64#include <linux/reboot.h>       /* For kernel_power_off() */
  65#include <linux/init.h>         /* For __init/__exit/... */
  66#include <linux/fs.h>           /* For file operations */
  67#include <linux/isa.h>          /* For isa devices */
  68#include <linux/ioport.h>       /* For io-port access */
  69#include <linux/spinlock.h>     /* For spin_lock/spin_unlock/... */
  70#include <linux/uaccess.h>      /* For copy_to_user/put_user/... */
  71#include <linux/io.h>           /* For inb/outb/... */
  72
  73/* Module and version information */
  74#define WATCHDOG_VERSION "1.20"
  75#define WATCHDOG_DATE "18 Feb 2007"
  76#define WATCHDOG_DRIVER_NAME "ISA-PC Watchdog"
  77#define WATCHDOG_NAME "pcwd"
  78#define PFX WATCHDOG_NAME ": "
  79#define DRIVER_VERSION WATCHDOG_DRIVER_NAME " driver, v" WATCHDOG_VERSION " (" WATCHDOG_DATE ")\n"
  80#define WD_VER WATCHDOG_VERSION " (" WATCHDOG_DATE ")"
  81
  82/*
  83 * It should be noted that PCWD_REVISION_B was removed because A and B
  84 * are essentially the same types of card, with the exception that B
  85 * has temperature reporting.  Since I didn't receive a Rev.B card,
  86 * the Rev.B card is not supported.  (It's a good thing too, as they
  87 * are no longer in production.)
  88 */
  89#define PCWD_REVISION_A         1
  90#define PCWD_REVISION_C         2
  91
  92/*
  93 * These are the auto-probe addresses available.
  94 *
  95 * Revision A only uses ports 0x270 and 0x370.  Revision C introduced 0x350.
  96 * Revision A has an address range of 2 addresses, while Revision C has 4.
  97 */
  98#define PCWD_ISA_NR_CARDS       3
  99static int pcwd_ioports[] = { 0x270, 0x350, 0x370, 0x000 };
 100
 101/*
 102 * These are the defines that describe the control status bits for the
 103 * PCI-PC Watchdog card.
 104*/
 105/* Port 1 : Control Status #1 for the PC Watchdog card, revision A. */
 106#define WD_WDRST                0x01    /* Previously reset state */
 107#define WD_T110                 0x02    /* Temperature overheat sense */
 108#define WD_HRTBT                0x04    /* Heartbeat sense */
 109#define WD_RLY2                 0x08    /* External relay triggered */
 110#define WD_SRLY2                0x80    /* Software external relay triggered */
 111/* Port 1 : Control Status #1 for the PC Watchdog card, revision C. */
 112#define WD_REVC_WTRP            0x01    /* Watchdog Trip status */
 113#define WD_REVC_HRBT            0x02    /* Watchdog Heartbeat */
 114#define WD_REVC_TTRP            0x04    /* Temperature Trip status */
 115#define WD_REVC_RL2A            0x08    /* Relay 2 activated by
 116                                                        on-board processor */
 117#define WD_REVC_RL1A            0x10    /* Relay 1 active */
 118#define WD_REVC_R2DS            0x40    /* Relay 2 disable */
 119#define WD_REVC_RLY2            0x80    /* Relay 2 activated? */
 120/* Port 2 : Control Status #2 */
 121#define WD_WDIS                 0x10    /* Watchdog Disabled */
 122#define WD_ENTP                 0x20    /* Watchdog Enable Temperature Trip */
 123#define WD_SSEL                 0x40    /* Watchdog Switch Select
 124                                                        (1:SW1 <-> 0:SW2) */
 125#define WD_WCMD                 0x80    /* Watchdog Command Mode */
 126
 127/* max. time we give an ISA watchdog card to process a command */
 128/* 500ms for each 4 bit response (according to spec.) */
 129#define ISA_COMMAND_TIMEOUT     1000
 130
 131/* Watchdog's internal commands */
 132#define CMD_ISA_IDLE                    0x00
 133#define CMD_ISA_VERSION_INTEGER         0x01
 134#define CMD_ISA_VERSION_TENTH           0x02
 135#define CMD_ISA_VERSION_HUNDRETH        0x03
 136#define CMD_ISA_VERSION_MINOR           0x04
 137#define CMD_ISA_SWITCH_SETTINGS         0x05
 138#define CMD_ISA_RESET_PC                0x06
 139#define CMD_ISA_ARM_0                   0x07
 140#define CMD_ISA_ARM_30                  0x08
 141#define CMD_ISA_ARM_60                  0x09
 142#define CMD_ISA_DELAY_TIME_2SECS        0x0A
 143#define CMD_ISA_DELAY_TIME_4SECS        0x0B
 144#define CMD_ISA_DELAY_TIME_8SECS        0x0C
 145#define CMD_ISA_RESET_RELAYS            0x0D
 146
 147/* Watchdog's Dip Switch heartbeat values */
 148static const int heartbeat_tbl[] = {
 149        20,     /* OFF-OFF-OFF  = 20 Sec  */
 150        40,     /* OFF-OFF-ON   = 40 Sec  */
 151        60,     /* OFF-ON-OFF   =  1 Min  */
 152        300,    /* OFF-ON-ON    =  5 Min  */
 153        600,    /* ON-OFF-OFF   = 10 Min  */
 154        1800,   /* ON-OFF-ON    = 30 Min  */
 155        3600,   /* ON-ON-OFF    =  1 Hour */
 156        7200,   /* ON-ON-ON     =  2 hour */
 157};
 158
 159/*
 160 * We are using an kernel timer to do the pinging of the watchdog
 161 * every ~500ms. We try to set the internal heartbeat of the
 162 * watchdog to 2 ms.
 163 */
 164
 165#define WDT_INTERVAL (HZ/2+1)
 166
 167/* We can only use 1 card due to the /dev/watchdog restriction */
 168static int cards_found;
 169
 170/* internal variables */
 171static unsigned long open_allowed;
 172static char expect_close;
 173static int temp_panic;
 174
 175/* this is private data for each ISA-PC watchdog card */
 176static struct {
 177        char fw_ver_str[6];             /* The cards firmware version */
 178        int revision;                   /* The card's revision */
 179        int supports_temp;              /* Whether or not the card has
 180                                                a temperature device */
 181        int command_mode;               /* Whether or not the card is in
 182                                                command mode */
 183        int boot_status;                /* The card's boot status */
 184        int io_addr;                    /* The cards I/O address */
 185        spinlock_t io_lock;             /* the lock for io operations */
 186        struct timer_list timer;        /* The timer that pings the watchdog */
 187        unsigned long next_heartbeat;   /* the next_heartbeat for the timer */
 188} pcwd_private;
 189
 190/* module parameters */
 191#define QUIET   0       /* Default */
 192#define VERBOSE 1       /* Verbose */
 193#define DEBUG   2       /* print fancy stuff too */
 194static int debug = QUIET;
 195module_param(debug, int, 0);
 196MODULE_PARM_DESC(debug,
 197                "Debug level: 0=Quiet, 1=Verbose, 2=Debug (default=0)");
 198
 199/* default heartbeat = delay-time from dip-switches */
 200#define WATCHDOG_HEARTBEAT 0
 201static int heartbeat = WATCHDOG_HEARTBEAT;
 202module_param(heartbeat, int, 0);
 203MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (2 <= heartbeat <= 7200 or 0=delay-time from dip-switches, default=" __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
 204
 205static int nowayout = WATCHDOG_NOWAYOUT;
 206module_param(nowayout, int, 0);
 207MODULE_PARM_DESC(nowayout,
 208                "Watchdog cannot be stopped once started (default="
 209                                __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 210
 211/*
 212 *      Internal functions
 213 */
 214
 215static int send_isa_command(int cmd)
 216{
 217        int i;
 218        int control_status;
 219        int port0, last_port0;  /* Double read for stabilising */
 220
 221        if (debug >= DEBUG)
 222                printk(KERN_DEBUG PFX "sending following data cmd=0x%02x\n",
 223                        cmd);
 224
 225        /* The WCMD bit must be 1 and the command is only 4 bits in size */
 226        control_status = (cmd & 0x0F) | WD_WCMD;
 227        outb_p(control_status, pcwd_private.io_addr + 2);
 228        udelay(ISA_COMMAND_TIMEOUT);
 229
 230        port0 = inb_p(pcwd_private.io_addr);
 231        for (i = 0; i < 25; ++i) {
 232                last_port0 = port0;
 233                port0 = inb_p(pcwd_private.io_addr);
 234
 235                if (port0 == last_port0)
 236                        break;  /* Data is stable */
 237
 238                udelay(250);
 239        }
 240
 241        if (debug >= DEBUG)
 242                printk(KERN_DEBUG PFX "received following data for cmd=0x%02x: port0=0x%02x last_port0=0x%02x\n",
 243                        cmd, port0, last_port0);
 244
 245        return port0;
 246}
 247
 248static int set_command_mode(void)
 249{
 250        int i, found = 0, count = 0;
 251
 252        /* Set the card into command mode */
 253        spin_lock(&pcwd_private.io_lock);
 254        while ((!found) && (count < 3)) {
 255                i = send_isa_command(CMD_ISA_IDLE);
 256
 257                if (i == 0x00)
 258                        found = 1;
 259                else if (i == 0xF3) {
 260                        /* Card does not like what we've done to it */
 261                        outb_p(0x00, pcwd_private.io_addr + 2);
 262                        udelay(1200);   /* Spec says wait 1ms */
 263                        outb_p(0x00, pcwd_private.io_addr + 2);
 264                        udelay(ISA_COMMAND_TIMEOUT);
 265                }
 266                count++;
 267        }
 268        spin_unlock(&pcwd_private.io_lock);
 269        pcwd_private.command_mode = found;
 270
 271        if (debug >= DEBUG)
 272                printk(KERN_DEBUG PFX "command_mode=%d\n",
 273                                pcwd_private.command_mode);
 274
 275        return found;
 276}
 277
 278static void unset_command_mode(void)
 279{
 280        /* Set the card into normal mode */
 281        spin_lock(&pcwd_private.io_lock);
 282        outb_p(0x00, pcwd_private.io_addr + 2);
 283        udelay(ISA_COMMAND_TIMEOUT);
 284        spin_unlock(&pcwd_private.io_lock);
 285
 286        pcwd_private.command_mode = 0;
 287
 288        if (debug >= DEBUG)
 289                printk(KERN_DEBUG PFX "command_mode=%d\n",
 290                                pcwd_private.command_mode);
 291}
 292
 293static inline void pcwd_check_temperature_support(void)
 294{
 295        if (inb(pcwd_private.io_addr) != 0xF0)
 296                pcwd_private.supports_temp = 1;
 297}
 298
 299static inline void pcwd_get_firmware(void)
 300{
 301        int one, ten, hund, minor;
 302
 303        strcpy(pcwd_private.fw_ver_str, "ERROR");
 304
 305        if (set_command_mode()) {
 306                one = send_isa_command(CMD_ISA_VERSION_INTEGER);
 307                ten = send_isa_command(CMD_ISA_VERSION_TENTH);
 308                hund = send_isa_command(CMD_ISA_VERSION_HUNDRETH);
 309                minor = send_isa_command(CMD_ISA_VERSION_MINOR);
 310                sprintf(pcwd_private.fw_ver_str, "%c.%c%c%c",
 311                                        one, ten, hund, minor);
 312        }
 313        unset_command_mode();
 314
 315        return;
 316}
 317
 318static inline int pcwd_get_option_switches(void)
 319{
 320        int option_switches = 0;
 321
 322        if (set_command_mode()) {
 323                /* Get switch settings */
 324                option_switches = send_isa_command(CMD_ISA_SWITCH_SETTINGS);
 325        }
 326
 327        unset_command_mode();
 328        return option_switches;
 329}
 330
 331static void pcwd_show_card_info(void)
 332{
 333        int option_switches;
 334
 335        /* Get some extra info from the hardware (in command/debug/diag mode) */
 336        if (pcwd_private.revision == PCWD_REVISION_A)
 337                printk(KERN_INFO PFX
 338                        "ISA-PC Watchdog (REV.A) detected at port 0x%04x\n",
 339                                                        pcwd_private.io_addr);
 340        else if (pcwd_private.revision == PCWD_REVISION_C) {
 341                pcwd_get_firmware();
 342                printk(KERN_INFO PFX "ISA-PC Watchdog (REV.C) detected at port 0x%04x (Firmware version: %s)\n",
 343                        pcwd_private.io_addr, pcwd_private.fw_ver_str);
 344                option_switches = pcwd_get_option_switches();
 345                printk(KERN_INFO PFX "Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
 346                        option_switches,
 347                        ((option_switches & 0x10) ? "ON" : "OFF"),
 348                        ((option_switches & 0x08) ? "ON" : "OFF"));
 349
 350                /* Reprogram internal heartbeat to 2 seconds */
 351                if (set_command_mode()) {
 352                        send_isa_command(CMD_ISA_DELAY_TIME_2SECS);
 353                        unset_command_mode();
 354                }
 355        }
 356
 357        if (pcwd_private.supports_temp)
 358                printk(KERN_INFO PFX "Temperature Option Detected\n");
 359
 360        if (pcwd_private.boot_status & WDIOF_CARDRESET)
 361                printk(KERN_INFO PFX "Previous reboot was caused by the card\n");
 362
 363        if (pcwd_private.boot_status & WDIOF_OVERHEAT) {
 364                printk(KERN_EMERG PFX
 365                        "Card senses a CPU Overheat. Panicking!\n");
 366                printk(KERN_EMERG PFX
 367                        "CPU Overheat\n");
 368        }
 369
 370        if (pcwd_private.boot_status == 0)
 371                printk(KERN_INFO PFX
 372                        "No previous trip detected - Cold boot or reset\n");
 373}
 374
 375static void pcwd_timer_ping(unsigned long data)
 376{
 377        int wdrst_stat;
 378
 379        /* If we got a heartbeat pulse within the WDT_INTERVAL
 380         * we agree to ping the WDT */
 381        if (time_before(jiffies, pcwd_private.next_heartbeat)) {
 382                /* Ping the watchdog */
 383                spin_lock(&pcwd_private.io_lock);
 384                if (pcwd_private.revision == PCWD_REVISION_A) {
 385                        /*  Rev A cards are reset by setting the
 386                            WD_WDRST bit in register 1 */
 387                        wdrst_stat = inb_p(pcwd_private.io_addr);
 388                        wdrst_stat &= 0x0F;
 389                        wdrst_stat |= WD_WDRST;
 390
 391                        outb_p(wdrst_stat, pcwd_private.io_addr + 1);
 392                } else {
 393                        /* Re-trigger watchdog by writing to port 0 */
 394                        outb_p(0x00, pcwd_private.io_addr);
 395                }
 396
 397                /* Re-set the timer interval */
 398                mod_timer(&pcwd_private.timer, jiffies + WDT_INTERVAL);
 399
 400                spin_unlock(&pcwd_private.io_lock);
 401        } else {
 402                printk(KERN_WARNING PFX
 403                        "Heartbeat lost! Will not ping the watchdog\n");
 404        }
 405}
 406
 407static int pcwd_start(void)
 408{
 409        int stat_reg;
 410
 411        pcwd_private.next_heartbeat = jiffies + (heartbeat * HZ);
 412
 413        /* Start the timer */
 414        mod_timer(&pcwd_private.timer, jiffies + WDT_INTERVAL);
 415
 416        /* Enable the port */
 417        if (pcwd_private.revision == PCWD_REVISION_C) {
 418                spin_lock(&pcwd_private.io_lock);
 419                outb_p(0x00, pcwd_private.io_addr + 3);
 420                udelay(ISA_COMMAND_TIMEOUT);
 421                stat_reg = inb_p(pcwd_private.io_addr + 2);
 422                spin_unlock(&pcwd_private.io_lock);
 423                if (stat_reg & WD_WDIS) {
 424                        printk(KERN_INFO PFX "Could not start watchdog\n");
 425                        return -EIO;
 426                }
 427        }
 428
 429        if (debug >= VERBOSE)
 430                printk(KERN_DEBUG PFX "Watchdog started\n");
 431
 432        return 0;
 433}
 434
 435static int pcwd_stop(void)
 436{
 437        int stat_reg;
 438
 439        /* Stop the timer */
 440        del_timer(&pcwd_private.timer);
 441
 442        /*  Disable the board  */
 443        if (pcwd_private.revision == PCWD_REVISION_C) {
 444                spin_lock(&pcwd_private.io_lock);
 445                outb_p(0xA5, pcwd_private.io_addr + 3);
 446                udelay(ISA_COMMAND_TIMEOUT);
 447                outb_p(0xA5, pcwd_private.io_addr + 3);
 448                udelay(ISA_COMMAND_TIMEOUT);
 449                stat_reg = inb_p(pcwd_private.io_addr + 2);
 450                spin_unlock(&pcwd_private.io_lock);
 451                if ((stat_reg & WD_WDIS) == 0) {
 452                        printk(KERN_INFO PFX "Could not stop watchdog\n");
 453                        return -EIO;
 454                }
 455        }
 456
 457        if (debug >= VERBOSE)
 458                printk(KERN_DEBUG PFX "Watchdog stopped\n");
 459
 460        return 0;
 461}
 462
 463static int pcwd_keepalive(void)
 464{
 465        /* user land ping */
 466        pcwd_private.next_heartbeat = jiffies + (heartbeat * HZ);
 467
 468        if (debug >= DEBUG)
 469                printk(KERN_DEBUG PFX "Watchdog keepalive signal send\n");
 470
 471        return 0;
 472}
 473
 474static int pcwd_set_heartbeat(int t)
 475{
 476        if (t < 2 || t > 7200) /* arbitrary upper limit */
 477                return -EINVAL;
 478
 479        heartbeat = t;
 480
 481        if (debug >= VERBOSE)
 482                printk(KERN_DEBUG PFX "New heartbeat: %d\n",
 483                       heartbeat);
 484
 485        return 0;
 486}
 487
 488static int pcwd_get_status(int *status)
 489{
 490        int control_status;
 491
 492        *status = 0;
 493        spin_lock(&pcwd_private.io_lock);
 494        if (pcwd_private.revision == PCWD_REVISION_A)
 495                /* Rev A cards return status information from
 496                 * the base register, which is used for the
 497                 * temperature in other cards. */
 498                control_status = inb(pcwd_private.io_addr);
 499        else {
 500                /* Rev C cards return card status in the base
 501                 * address + 1 register. And use different bits
 502                 * to indicate a card initiated reset, and an
 503                 * over-temperature condition. And the reboot
 504                 * status can be reset. */
 505                control_status = inb(pcwd_private.io_addr + 1);
 506        }
 507        spin_unlock(&pcwd_private.io_lock);
 508
 509        if (pcwd_private.revision == PCWD_REVISION_A) {
 510                if (control_status & WD_WDRST)
 511                        *status |= WDIOF_CARDRESET;
 512
 513                if (control_status & WD_T110) {
 514                        *status |= WDIOF_OVERHEAT;
 515                        if (temp_panic) {
 516                                printk(KERN_INFO PFX
 517                                        "Temperature overheat trip!\n");
 518                                kernel_power_off();
 519                        }
 520                }
 521        } else {
 522                if (control_status & WD_REVC_WTRP)
 523                        *status |= WDIOF_CARDRESET;
 524
 525                if (control_status & WD_REVC_TTRP) {
 526                        *status |= WDIOF_OVERHEAT;
 527                        if (temp_panic) {
 528                                printk(KERN_INFO PFX
 529                                        "Temperature overheat trip!\n");
 530                                kernel_power_off();
 531                        }
 532                }
 533        }
 534
 535        return 0;
 536}
 537
 538static int pcwd_clear_status(void)
 539{
 540        int control_status;
 541
 542        if (pcwd_private.revision == PCWD_REVISION_C) {
 543                spin_lock(&pcwd_private.io_lock);
 544
 545                if (debug >= VERBOSE)
 546                        printk(KERN_INFO PFX
 547                                        "clearing watchdog trip status\n");
 548
 549                control_status = inb_p(pcwd_private.io_addr + 1);
 550
 551                if (debug >= DEBUG) {
 552                        printk(KERN_DEBUG PFX "status was: 0x%02x\n",
 553                                control_status);
 554                        printk(KERN_DEBUG PFX "sending: 0x%02x\n",
 555                                (control_status & WD_REVC_R2DS));
 556                }
 557
 558                /* clear reset status & Keep Relay 2 disable state as it is */
 559                outb_p((control_status & WD_REVC_R2DS),
 560                                                pcwd_private.io_addr + 1);
 561
 562                spin_unlock(&pcwd_private.io_lock);
 563        }
 564        return 0;
 565}
 566
 567static int pcwd_get_temperature(int *temperature)
 568{
 569        /* check that port 0 gives temperature info and no command results */
 570        if (pcwd_private.command_mode)
 571                return -1;
 572
 573        *temperature = 0;
 574        if (!pcwd_private.supports_temp)
 575                return -ENODEV;
 576
 577        /*
 578         * Convert celsius to fahrenheit, since this was
 579         * the decided 'standard' for this return value.
 580         */
 581        spin_lock(&pcwd_private.io_lock);
 582        *temperature = ((inb(pcwd_private.io_addr)) * 9 / 5) + 32;
 583        spin_unlock(&pcwd_private.io_lock);
 584
 585        if (debug >= DEBUG) {
 586                printk(KERN_DEBUG PFX "temperature is: %d F\n",
 587                        *temperature);
 588        }
 589
 590        return 0;
 591}
 592
 593/*
 594 *      /dev/watchdog handling
 595 */
 596
 597static long pcwd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 598{
 599        int rv;
 600        int status;
 601        int temperature;
 602        int new_heartbeat;
 603        int __user *argp = (int __user *)arg;
 604        static struct watchdog_info ident = {
 605                .options =              WDIOF_OVERHEAT |
 606                                        WDIOF_CARDRESET |
 607                                        WDIOF_KEEPALIVEPING |
 608                                        WDIOF_SETTIMEOUT |
 609                                        WDIOF_MAGICCLOSE,
 610                .firmware_version =     1,
 611                .identity =             "PCWD",
 612        };
 613
 614        switch (cmd) {
 615        case WDIOC_GETSUPPORT:
 616                if (copy_to_user(argp, &ident, sizeof(ident)))
 617                        return -EFAULT;
 618                return 0;
 619
 620        case WDIOC_GETSTATUS:
 621                pcwd_get_status(&status);
 622                return put_user(status, argp);
 623
 624        case WDIOC_GETBOOTSTATUS:
 625                return put_user(pcwd_private.boot_status, argp);
 626
 627        case WDIOC_GETTEMP:
 628                if (pcwd_get_temperature(&temperature))
 629                        return -EFAULT;
 630
 631                return put_user(temperature, argp);
 632
 633        case WDIOC_SETOPTIONS:
 634                if (pcwd_private.revision == PCWD_REVISION_C) {
 635                        if (get_user(rv, argp))
 636                                return -EFAULT;
 637
 638                        if (rv & WDIOS_DISABLECARD) {
 639                                status = pcwd_stop();
 640                                if (status < 0)
 641                                        return status;
 642                        }
 643                        if (rv & WDIOS_ENABLECARD) {
 644                                status = pcwd_start();
 645                                if (status < 0)
 646                                        return status;
 647                        }
 648                        if (rv & WDIOS_TEMPPANIC)
 649                                temp_panic = 1;
 650                }
 651                return -EINVAL;
 652
 653        case WDIOC_KEEPALIVE:
 654                pcwd_keepalive();
 655                return 0;
 656
 657        case WDIOC_SETTIMEOUT:
 658                if (get_user(new_heartbeat, argp))
 659                        return -EFAULT;
 660
 661                if (pcwd_set_heartbeat(new_heartbeat))
 662                        return -EINVAL;
 663
 664                pcwd_keepalive();
 665                /* Fall */
 666
 667        case WDIOC_GETTIMEOUT:
 668                return put_user(heartbeat, argp);
 669
 670        default:
 671                return -ENOTTY;
 672        }
 673
 674        return 0;
 675}
 676
 677static ssize_t pcwd_write(struct file *file, const char __user *buf, size_t len,
 678                          loff_t *ppos)
 679{
 680        if (len) {
 681                if (!nowayout) {
 682                        size_t i;
 683
 684                        /* In case it was set long ago */
 685                        expect_close = 0;
 686
 687                        for (i = 0; i != len; i++) {
 688                                char c;
 689
 690                                if (get_user(c, buf + i))
 691                                        return -EFAULT;
 692                                if (c == 'V')
 693                                        expect_close = 42;
 694                        }
 695                }
 696                pcwd_keepalive();
 697        }
 698        return len;
 699}
 700
 701static int pcwd_open(struct inode *inode, struct file *file)
 702{
 703        if (test_and_set_bit(0, &open_allowed))
 704                return -EBUSY;
 705        if (nowayout)
 706                __module_get(THIS_MODULE);
 707        /* Activate */
 708        pcwd_start();
 709        pcwd_keepalive();
 710        return nonseekable_open(inode, file);
 711}
 712
 713static int pcwd_close(struct inode *inode, struct file *file)
 714{
 715        if (expect_close == 42)
 716                pcwd_stop();
 717        else {
 718                printk(KERN_CRIT PFX
 719                        "Unexpected close, not stopping watchdog!\n");
 720                pcwd_keepalive();
 721        }
 722        expect_close = 0;
 723        clear_bit(0, &open_allowed);
 724        return 0;
 725}
 726
 727/*
 728 *      /dev/temperature handling
 729 */
 730
 731static ssize_t pcwd_temp_read(struct file *file, char __user *buf, size_t count,
 732                         loff_t *ppos)
 733{
 734        int temperature;
 735
 736        if (pcwd_get_temperature(&temperature))
 737                return -EFAULT;
 738
 739        if (copy_to_user(buf, &temperature, 1))
 740                return -EFAULT;
 741
 742        return 1;
 743}
 744
 745static int pcwd_temp_open(struct inode *inode, struct file *file)
 746{
 747        if (!pcwd_private.supports_temp)
 748                return -ENODEV;
 749
 750        return nonseekable_open(inode, file);
 751}
 752
 753static int pcwd_temp_close(struct inode *inode, struct file *file)
 754{
 755        return 0;
 756}
 757
 758/*
 759 *      Kernel Interfaces
 760 */
 761
 762static const struct file_operations pcwd_fops = {
 763        .owner          = THIS_MODULE,
 764        .llseek         = no_llseek,
 765        .write          = pcwd_write,
 766        .unlocked_ioctl = pcwd_ioctl,
 767        .open           = pcwd_open,
 768        .release        = pcwd_close,
 769};
 770
 771static struct miscdevice pcwd_miscdev = {
 772        .minor =        WATCHDOG_MINOR,
 773        .name =         "watchdog",
 774        .fops =         &pcwd_fops,
 775};
 776
 777static const struct file_operations pcwd_temp_fops = {
 778        .owner          = THIS_MODULE,
 779        .llseek         = no_llseek,
 780        .read           = pcwd_temp_read,
 781        .open           = pcwd_temp_open,
 782        .release        = pcwd_temp_close,
 783};
 784
 785static struct miscdevice temp_miscdev = {
 786        .minor =        TEMP_MINOR,
 787        .name =         "temperature",
 788        .fops =         &pcwd_temp_fops,
 789};
 790
 791/*
 792 *      Init & exit routines
 793 */
 794
 795static inline int get_revision(void)
 796{
 797        int r = PCWD_REVISION_C;
 798
 799        spin_lock(&pcwd_private.io_lock);
 800        /* REV A cards use only 2 io ports; test
 801         * presumes a floating bus reads as 0xff. */
 802        if ((inb(pcwd_private.io_addr + 2) == 0xFF) ||
 803            (inb(pcwd_private.io_addr + 3) == 0xFF))
 804                r = PCWD_REVISION_A;
 805        spin_unlock(&pcwd_private.io_lock);
 806
 807        return r;
 808}
 809
 810/*
 811 *  The ISA cards have a heartbeat bit in one of the registers, which
 812 *  register is card dependent.  The heartbeat bit is monitored, and if
 813 *  found, is considered proof that a Berkshire card has been found.
 814 *  The initial rate is once per second at board start up, then twice
 815 *  per second for normal operation.
 816 */
 817static int __devinit pcwd_isa_match(struct device *dev, unsigned int id)
 818{
 819        int base_addr = pcwd_ioports[id];
 820        int port0, last_port0;  /* Reg 0, in case it's REV A */
 821        int port1, last_port1;  /* Register 1 for REV C cards */
 822        int i;
 823        int retval;
 824
 825        if (debug >= DEBUG)
 826                printk(KERN_DEBUG PFX "pcwd_isa_match id=%d\n",
 827                        id);
 828
 829        if (!request_region(base_addr, 4, "PCWD")) {
 830                printk(KERN_INFO PFX "Port 0x%04x unavailable\n", base_addr);
 831                return 0;
 832        }
 833
 834        retval = 0;
 835
 836        port0 = inb_p(base_addr);       /* For REV A boards */
 837        port1 = inb_p(base_addr + 1);   /* For REV C boards */
 838        if (port0 != 0xff || port1 != 0xff) {
 839                /* Not an 'ff' from a floating bus, so must be a card! */
 840                for (i = 0; i < 4; ++i) {
 841
 842                        msleep(500);
 843
 844                        last_port0 = port0;
 845                        last_port1 = port1;
 846
 847                        port0 = inb_p(base_addr);
 848                        port1 = inb_p(base_addr + 1);
 849
 850                        /* Has either hearbeat bit changed?  */
 851                        if ((port0 ^ last_port0) & WD_HRTBT ||
 852                            (port1 ^ last_port1) & WD_REVC_HRBT) {
 853                                retval = 1;
 854                                break;
 855                        }
 856                }
 857        }
 858        release_region(base_addr, 4);
 859
 860        return retval;
 861}
 862
 863static int __devinit pcwd_isa_probe(struct device *dev, unsigned int id)
 864{
 865        int ret;
 866
 867        if (debug >= DEBUG)
 868                printk(KERN_DEBUG PFX "pcwd_isa_probe id=%d\n",
 869                        id);
 870
 871        cards_found++;
 872        if (cards_found == 1)
 873                printk(KERN_INFO PFX "v%s Ken Hollis (kenji@bitgate.com)\n",
 874                                                                WD_VER);
 875
 876        if (cards_found > 1) {
 877                printk(KERN_ERR PFX "This driver only supports 1 device\n");
 878                return -ENODEV;
 879        }
 880
 881        if (pcwd_ioports[id] == 0x0000) {
 882                printk(KERN_ERR PFX "No I/O-Address for card detected\n");
 883                return -ENODEV;
 884        }
 885        pcwd_private.io_addr = pcwd_ioports[id];
 886
 887        spin_lock_init(&pcwd_private.io_lock);
 888
 889        /* Check card's revision */
 890        pcwd_private.revision = get_revision();
 891
 892        if (!request_region(pcwd_private.io_addr,
 893                (pcwd_private.revision == PCWD_REVISION_A) ? 2 : 4, "PCWD")) {
 894                printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
 895                        pcwd_private.io_addr);
 896                ret = -EIO;
 897                goto error_request_region;
 898        }
 899
 900        /* Initial variables */
 901        pcwd_private.supports_temp = 0;
 902        temp_panic = 0;
 903        pcwd_private.boot_status = 0x0000;
 904
 905        /* get the boot_status */
 906        pcwd_get_status(&pcwd_private.boot_status);
 907
 908        /* clear the "card caused reboot" flag */
 909        pcwd_clear_status();
 910
 911        setup_timer(&pcwd_private.timer, pcwd_timer_ping, 0);
 912
 913        /*  Disable the board  */
 914        pcwd_stop();
 915
 916        /*  Check whether or not the card supports the temperature device */
 917        pcwd_check_temperature_support();
 918
 919        /* Show info about the card itself */
 920        pcwd_show_card_info();
 921
 922        /* If heartbeat = 0 then we use the heartbeat from the dip-switches */
 923        if (heartbeat == 0)
 924                heartbeat = heartbeat_tbl[(pcwd_get_option_switches() & 0x07)];
 925
 926        /* Check that the heartbeat value is within it's range;
 927           if not reset to the default */
 928        if (pcwd_set_heartbeat(heartbeat)) {
 929                pcwd_set_heartbeat(WATCHDOG_HEARTBEAT);
 930                printk(KERN_INFO PFX
 931                  "heartbeat value must be 2 <= heartbeat <= 7200, using %d\n",
 932                                                        WATCHDOG_HEARTBEAT);
 933        }
 934
 935        if (pcwd_private.supports_temp) {
 936                ret = misc_register(&temp_miscdev);
 937                if (ret) {
 938                        printk(KERN_ERR PFX
 939                            "cannot register miscdev on minor=%d (err=%d)\n",
 940                                                        TEMP_MINOR, ret);
 941                        goto error_misc_register_temp;
 942                }
 943        }
 944
 945        ret = misc_register(&pcwd_miscdev);
 946        if (ret) {
 947                printk(KERN_ERR PFX
 948                        "cannot register miscdev on minor=%d (err=%d)\n",
 949                                        WATCHDOG_MINOR, ret);
 950                goto error_misc_register_watchdog;
 951        }
 952
 953        printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
 954                heartbeat, nowayout);
 955
 956        return 0;
 957
 958error_misc_register_watchdog:
 959        if (pcwd_private.supports_temp)
 960                misc_deregister(&temp_miscdev);
 961error_misc_register_temp:
 962        release_region(pcwd_private.io_addr,
 963                        (pcwd_private.revision == PCWD_REVISION_A) ? 2 : 4);
 964error_request_region:
 965        pcwd_private.io_addr = 0x0000;
 966        cards_found--;
 967        return ret;
 968}
 969
 970static int __devexit pcwd_isa_remove(struct device *dev, unsigned int id)
 971{
 972        if (debug >= DEBUG)
 973                printk(KERN_DEBUG PFX "pcwd_isa_remove id=%d\n",
 974                        id);
 975
 976        if (!pcwd_private.io_addr)
 977                return 1;
 978
 979        /*  Disable the board  */
 980        if (!nowayout)
 981                pcwd_stop();
 982
 983        /* Deregister */
 984        misc_deregister(&pcwd_miscdev);
 985        if (pcwd_private.supports_temp)
 986                misc_deregister(&temp_miscdev);
 987        release_region(pcwd_private.io_addr,
 988                        (pcwd_private.revision == PCWD_REVISION_A) ? 2 : 4);
 989        pcwd_private.io_addr = 0x0000;
 990        cards_found--;
 991
 992        return 0;
 993}
 994
 995static void pcwd_isa_shutdown(struct device *dev, unsigned int id)
 996{
 997        if (debug >= DEBUG)
 998                printk(KERN_DEBUG PFX "pcwd_isa_shutdown id=%d\n",
 999                        id);
1000
1001        pcwd_stop();
1002}
1003
1004static struct isa_driver pcwd_isa_driver = {
1005        .match          = pcwd_isa_match,
1006        .probe          = pcwd_isa_probe,
1007        .remove         = __devexit_p(pcwd_isa_remove),
1008        .shutdown       = pcwd_isa_shutdown,
1009        .driver         = {
1010                .owner  = THIS_MODULE,
1011                .name   = WATCHDOG_NAME,
1012        },
1013};
1014
1015static int __init pcwd_init_module(void)
1016{
1017        return isa_register_driver(&pcwd_isa_driver, PCWD_ISA_NR_CARDS);
1018}
1019
1020static void __exit pcwd_cleanup_module(void)
1021{
1022        isa_unregister_driver(&pcwd_isa_driver);
1023        printk(KERN_INFO PFX "Watchdog Module Unloaded.\n");
1024}
1025
1026module_init(pcwd_init_module);
1027module_exit(pcwd_cleanup_module);
1028
1029MODULE_AUTHOR("Ken Hollis <kenji@bitgate.com>, Wim Van Sebroeck <wim@iguana.be>");
1030MODULE_DESCRIPTION("Berkshire ISA-PC Watchdog driver");
1031MODULE_VERSION(WATCHDOG_VERSION);
1032MODULE_LICENSE("GPL");
1033MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
1034MODULE_ALIAS_MISCDEV(TEMP_MINOR);
1035