kernel-ark/drivers/char/watchdog/pcwd.c
Tim Schmielau 4e57b68178 [PATCH] fix missing includes
I recently picked up my older work to remove unnecessary #includes of
sched.h, starting from a patch by Dave Jones to not include sched.h
from module.h. This reduces the number of indirect includes of sched.h
by ~300. Another ~400 pointless direct includes can be removed after
this disentangling (patch to follow later).
However, quite a few indirect includes need to be fixed up for this.

In order to feed the patches through -mm with as little disturbance as
possible, I've split out the fixes I accumulated up to now (complete for
i386 and x86_64, more archs to follow later) and post them before the real
patch.  This way this large part of the patch is kept simple with only
adding #includes, and all hunks are independent of each other.  So if any
hunk rejects or gets in the way of other patches, just drop it.  My scripts
will pick it up again in the next round.

Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:32 -08:00

922 lines
23 KiB
C

/*
* PC Watchdog Driver
* by Ken Hollis (khollis@bitgate.com)
*
* Permission granted from Simon Machell (73244.1270@compuserve.com)
* Written for the Linux Kernel, and GPLed by Ken Hollis
*
* 960107 Added request_region routines, modulized the whole thing.
* 960108 Fixed end-of-file pointer (Thanks to Dan Hollis), added
* WD_TIMEOUT define.
* 960216 Added eof marker on the file, and changed verbose messages.
* 960716 Made functional and cosmetic changes to the source for
* inclusion in Linux 2.0.x kernels, thanks to Alan Cox.
* 960717 Removed read/seek routines, replaced with ioctl. Also, added
* check_region command due to Alan's suggestion.
* 960821 Made changes to compile in newer 2.0.x kernels. Added
* "cold reboot sense" entry.
* 960825 Made a few changes to code, deleted some defines and made
* typedefs to replace them. Made heartbeat reset only available
* via ioctl, and removed the write routine.
* 960828 Added new items for PC Watchdog Rev.C card.
* 960829 Changed around all of the IOCTLs, added new features,
* added watchdog disable/re-enable routines. Added firmware
* version reporting. Added read routine for temperature.
* Removed some extra defines, added an autodetect Revision
* routine.
* 961006 Revised some documentation, fixed some cosmetic bugs. Made
* drivers to panic the system if it's overheating at bootup.
* 961118 Changed some verbiage on some of the output, tidied up
* code bits, and added compatibility to 2.1.x.
* 970912 Enabled board on open and disable on close.
* 971107 Took account of recent VFS changes (broke read).
* 971210 Disable board on initialisation in case board already ticking.
* 971222 Changed open/close for temperature handling
* Michael Meskes <meskes@debian.org>.
* 980112 Used minor numbers from include/linux/miscdevice.h
* 990403 Clear reset status after reading control status register in
* pcwd_showprevstate(). [Marc Boucher <marc@mbsi.ca>]
* 990605 Made changes to code to support Firmware 1.22a, added
* fairly useless proc entry.
* 990610 removed said useless proc code for the merge <alan>
* 000403 Removed last traces of proc code. <davej>
* 011214 Added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT <Matt_Domsch@dell.com>
* Added timeout module option to override default
*/
/*
* A bells and whistles driver is available from http://www.pcwd.de/
* More info available at http://www.berkprod.com/ or http://www.pcwatchdog.com/
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/timer.h>
#include <linux/jiffies.h>
#include <linux/config.h>
#include <linux/wait.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/notifier.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/reboot.h>
#include <linux/sched.h> /* TASK_INTERRUPTIBLE, set_current_state() and friends */
#include <asm/uaccess.h>
#include <asm/io.h>
#define WD_VER "1.16 (06/12/2004)"
#define PFX "pcwd: "
/*
* It should be noted that PCWD_REVISION_B was removed because A and B
* are essentially the same types of card, with the exception that B
* has temperature reporting. Since I didn't receive a Rev.B card,
* the Rev.B card is not supported. (It's a good thing too, as they
* are no longer in production.)
*/
#define PCWD_REVISION_A 1
#define PCWD_REVISION_C 2
/*
* These are the defines that describe the control status bits for the
* PC Watchdog card, revision A.
*/
#define WD_WDRST 0x01 /* Previously reset state */
#define WD_T110 0x02 /* Temperature overheat sense */
#define WD_HRTBT 0x04 /* Heartbeat sense */
#define WD_RLY2 0x08 /* External relay triggered */
#define WD_SRLY2 0x80 /* Software external relay triggered */
/*
* These are the defines that describe the control status bits for the
* PC Watchdog card, revision C.
*/
#define WD_REVC_WTRP 0x01 /* Watchdog Trip status */
#define WD_REVC_HRBT 0x02 /* Watchdog Heartbeat */
#define WD_REVC_TTRP 0x04 /* Temperature Trip status */
/* max. time we give an ISA watchdog card to process a command */
/* 500ms for each 4 bit response (according to spec.) */
#define ISA_COMMAND_TIMEOUT 1000
/* Watchdog's internal commands */
#define CMD_ISA_IDLE 0x00
#define CMD_ISA_VERSION_INTEGER 0x01
#define CMD_ISA_VERSION_TENTH 0x02
#define CMD_ISA_VERSION_HUNDRETH 0x03
#define CMD_ISA_VERSION_MINOR 0x04
#define CMD_ISA_SWITCH_SETTINGS 0x05
#define CMD_ISA_DELAY_TIME_2SECS 0x0A
#define CMD_ISA_DELAY_TIME_4SECS 0x0B
#define CMD_ISA_DELAY_TIME_8SECS 0x0C
/*
* We are using an kernel timer to do the pinging of the watchdog
* every ~500ms. We try to set the internal heartbeat of the
* watchdog to 2 ms.
*/
#define WDT_INTERVAL (HZ/2+1)
/* We can only use 1 card due to the /dev/watchdog restriction */
static int cards_found;
/* internal variables */
static atomic_t open_allowed = ATOMIC_INIT(1);
static char expect_close;
static struct timer_list timer;
static unsigned long next_heartbeat;
static int temp_panic;
static int revision; /* The card's revision */
static int supports_temp; /* Wether or not the card has a temperature device */
static int command_mode; /* Wether or not the card is in command mode */
static int initial_status; /* The card's boot status */
static int current_readport; /* The cards I/O address */
static spinlock_t io_lock;
/* module parameters */
#define WATCHDOG_HEARTBEAT 60 /* 60 sec default heartbeat */
static int heartbeat = WATCHDOG_HEARTBEAT;
module_param(heartbeat, int, 0);
MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (2<=heartbeat<=7200, default=" __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
static int nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, int, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
/*
* Internal functions
*/
static int send_isa_command(int cmd)
{
int i;
int control_status;
int port0, last_port0; /* Double read for stabilising */
/* The WCMD bit must be 1 and the command is only 4 bits in size */
control_status = (cmd & 0x0F) | 0x80;
outb_p(control_status, current_readport + 2);
udelay(ISA_COMMAND_TIMEOUT);
port0 = inb_p(current_readport);
for (i = 0; i < 25; ++i) {
last_port0 = port0;
port0 = inb_p(current_readport);
if (port0 == last_port0)
break; /* Data is stable */
udelay (250);
}
return port0;
}
static int set_command_mode(void)
{
int i, found=0, count=0;
/* Set the card into command mode */
spin_lock(&io_lock);
while ((!found) && (count < 3)) {
i = send_isa_command(CMD_ISA_IDLE);
if (i == 0x00)
found = 1;
else if (i == 0xF3) {
/* Card does not like what we've done to it */
outb_p(0x00, current_readport + 2);
udelay(1200); /* Spec says wait 1ms */
outb_p(0x00, current_readport + 2);
udelay(ISA_COMMAND_TIMEOUT);
}
count++;
}
spin_unlock(&io_lock);
command_mode = found;
return(found);
}
static void unset_command_mode(void)
{
/* Set the card into normal mode */
spin_lock(&io_lock);
outb_p(0x00, current_readport + 2);
udelay(ISA_COMMAND_TIMEOUT);
spin_unlock(&io_lock);
command_mode = 0;
}
static void pcwd_timer_ping(unsigned long data)
{
int wdrst_stat;
/* If we got a heartbeat pulse within the WDT_INTERVAL
* we agree to ping the WDT */
if(time_before(jiffies, next_heartbeat)) {
/* Ping the watchdog */
spin_lock(&io_lock);
if (revision == PCWD_REVISION_A) {
/* Rev A cards are reset by setting the WD_WDRST bit in register 1 */
wdrst_stat = inb_p(current_readport);
wdrst_stat &= 0x0F;
wdrst_stat |= WD_WDRST;
outb_p(wdrst_stat, current_readport + 1);
} else {
/* Re-trigger watchdog by writing to port 0 */
outb_p(0x00, current_readport);
}
/* Re-set the timer interval */
mod_timer(&timer, jiffies + WDT_INTERVAL);
spin_unlock(&io_lock);
} else {
printk(KERN_WARNING PFX "Heartbeat lost! Will not ping the watchdog\n");
}
}
static int pcwd_start(void)
{
int stat_reg;
next_heartbeat = jiffies + (heartbeat * HZ);
/* Start the timer */
mod_timer(&timer, jiffies + WDT_INTERVAL);
/* Enable the port */
if (revision == PCWD_REVISION_C) {
spin_lock(&io_lock);
outb_p(0x00, current_readport + 3);
udelay(ISA_COMMAND_TIMEOUT);
stat_reg = inb_p(current_readport + 2);
spin_unlock(&io_lock);
if (stat_reg & 0x10) {
printk(KERN_INFO PFX "Could not start watchdog\n");
return -EIO;
}
}
return 0;
}
static int pcwd_stop(void)
{
int stat_reg;
/* Stop the timer */
del_timer(&timer);
/* Disable the board */
if (revision == PCWD_REVISION_C) {
spin_lock(&io_lock);
outb_p(0xA5, current_readport + 3);
udelay(ISA_COMMAND_TIMEOUT);
outb_p(0xA5, current_readport + 3);
udelay(ISA_COMMAND_TIMEOUT);
stat_reg = inb_p(current_readport + 2);
spin_unlock(&io_lock);
if ((stat_reg & 0x10) == 0) {
printk(KERN_INFO PFX "Could not stop watchdog\n");
return -EIO;
}
}
return 0;
}
static int pcwd_keepalive(void)
{
/* user land ping */
next_heartbeat = jiffies + (heartbeat * HZ);
return 0;
}
static int pcwd_set_heartbeat(int t)
{
if ((t < 2) || (t > 7200)) /* arbitrary upper limit */
return -EINVAL;
heartbeat = t;
return 0;
}
static int pcwd_get_status(int *status)
{
int card_status;
*status=0;
spin_lock(&io_lock);
if (revision == PCWD_REVISION_A)
/* Rev A cards return status information from
* the base register, which is used for the
* temperature in other cards. */
card_status = inb(current_readport);
else {
/* Rev C cards return card status in the base
* address + 1 register. And use different bits
* to indicate a card initiated reset, and an
* over-temperature condition. And the reboot
* status can be reset. */
card_status = inb(current_readport + 1);
}
spin_unlock(&io_lock);
if (revision == PCWD_REVISION_A) {
if (card_status & WD_WDRST)
*status |= WDIOF_CARDRESET;
if (card_status & WD_T110) {
*status |= WDIOF_OVERHEAT;
if (temp_panic) {
printk (KERN_INFO PFX "Temperature overheat trip!\n");
kernel_power_off();
}
}
} else {
if (card_status & WD_REVC_WTRP)
*status |= WDIOF_CARDRESET;
if (card_status & WD_REVC_TTRP) {
*status |= WDIOF_OVERHEAT;
if (temp_panic) {
printk (KERN_INFO PFX "Temperature overheat trip!\n");
kernel_power_off();
}
}
}
return 0;
}
static int pcwd_clear_status(void)
{
if (revision == PCWD_REVISION_C) {
spin_lock(&io_lock);
outb_p(0x00, current_readport + 1); /* clear reset status */
spin_unlock(&io_lock);
}
return 0;
}
static int pcwd_get_temperature(int *temperature)
{
/* check that port 0 gives temperature info and no command results */
if (command_mode)
return -1;
*temperature = 0;
if (!supports_temp)
return -ENODEV;
/*
* Convert celsius to fahrenheit, since this was
* the decided 'standard' for this return value.
*/
spin_lock(&io_lock);
*temperature = ((inb(current_readport)) * 9 / 5) + 32;
spin_unlock(&io_lock);
return 0;
}
/*
* /dev/watchdog handling
*/
static int pcwd_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
int rv;
int status;
int temperature;
int new_heartbeat;
int __user *argp = (int __user *)arg;
static struct watchdog_info ident = {
.options = WDIOF_OVERHEAT |
WDIOF_CARDRESET |
WDIOF_KEEPALIVEPING |
WDIOF_SETTIMEOUT |
WDIOF_MAGICCLOSE,
.firmware_version = 1,
.identity = "PCWD",
};
switch(cmd) {
default:
return -ENOIOCTLCMD;
case WDIOC_GETSUPPORT:
if(copy_to_user(argp, &ident, sizeof(ident)))
return -EFAULT;
return 0;
case WDIOC_GETSTATUS:
pcwd_get_status(&status);
return put_user(status, argp);
case WDIOC_GETBOOTSTATUS:
return put_user(initial_status, argp);
case WDIOC_GETTEMP:
if (pcwd_get_temperature(&temperature))
return -EFAULT;
return put_user(temperature, argp);
case WDIOC_SETOPTIONS:
if (revision == PCWD_REVISION_C)
{
if(copy_from_user(&rv, argp, sizeof(int)))
return -EFAULT;
if (rv & WDIOS_DISABLECARD)
{
return pcwd_stop();
}
if (rv & WDIOS_ENABLECARD)
{
return pcwd_start();
}
if (rv & WDIOS_TEMPPANIC)
{
temp_panic = 1;
}
}
return -EINVAL;
case WDIOC_KEEPALIVE:
pcwd_keepalive();
return 0;
case WDIOC_SETTIMEOUT:
if (get_user(new_heartbeat, argp))
return -EFAULT;
if (pcwd_set_heartbeat(new_heartbeat))
return -EINVAL;
pcwd_keepalive();
/* Fall */
case WDIOC_GETTIMEOUT:
return put_user(heartbeat, argp);
}
return 0;
}
static ssize_t pcwd_write(struct file *file, const char __user *buf, size_t len,
loff_t *ppos)
{
if (len) {
if (!nowayout) {
size_t i;
/* In case it was set long ago */
expect_close = 0;
for (i = 0; i != len; i++) {
char c;
if (get_user(c, buf + i))
return -EFAULT;
if (c == 'V')
expect_close = 42;
}
}
pcwd_keepalive();
}
return len;
}
static int pcwd_open(struct inode *inode, struct file *file)
{
if (!atomic_dec_and_test(&open_allowed) ) {
atomic_inc( &open_allowed );
return -EBUSY;
}
if (nowayout)
__module_get(THIS_MODULE);
/* Activate */
pcwd_start();
pcwd_keepalive();
return nonseekable_open(inode, file);
}
static int pcwd_close(struct inode *inode, struct file *file)
{
if (expect_close == 42) {
pcwd_stop();
} else {
printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
pcwd_keepalive();
}
expect_close = 0;
atomic_inc( &open_allowed );
return 0;
}
/*
* /dev/temperature handling
*/
static ssize_t pcwd_temp_read(struct file *file, char __user *buf, size_t count,
loff_t *ppos)
{
int temperature;
if (pcwd_get_temperature(&temperature))
return -EFAULT;
if (copy_to_user(buf, &temperature, 1))
return -EFAULT;
return 1;
}
static int pcwd_temp_open(struct inode *inode, struct file *file)
{
if (!supports_temp)
return -ENODEV;
return nonseekable_open(inode, file);
}
static int pcwd_temp_close(struct inode *inode, struct file *file)
{
return 0;
}
/*
* Notify system
*/
static int pcwd_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
{
if (code==SYS_DOWN || code==SYS_HALT) {
/* Turn the WDT off */
pcwd_stop();
}
return NOTIFY_DONE;
}
/*
* Kernel Interfaces
*/
static struct file_operations pcwd_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = pcwd_write,
.ioctl = pcwd_ioctl,
.open = pcwd_open,
.release = pcwd_close,
};
static struct miscdevice pcwd_miscdev = {
.minor = WATCHDOG_MINOR,
.name = "watchdog",
.fops = &pcwd_fops,
};
static struct file_operations pcwd_temp_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.read = pcwd_temp_read,
.open = pcwd_temp_open,
.release = pcwd_temp_close,
};
static struct miscdevice temp_miscdev = {
.minor = TEMP_MINOR,
.name = "temperature",
.fops = &pcwd_temp_fops,
};
static struct notifier_block pcwd_notifier = {
.notifier_call = pcwd_notify_sys,
};
/*
* Init & exit routines
*/
static inline void get_support(void)
{
if (inb(current_readport) != 0xF0)
supports_temp = 1;
}
static inline int get_revision(void)
{
int r = PCWD_REVISION_C;
spin_lock(&io_lock);
/* REV A cards use only 2 io ports; test
* presumes a floating bus reads as 0xff. */
if ((inb(current_readport + 2) == 0xFF) ||
(inb(current_readport + 3) == 0xFF))
r=PCWD_REVISION_A;
spin_unlock(&io_lock);
return r;
}
static inline char *get_firmware(void)
{
int one, ten, hund, minor;
char *ret;
ret = kmalloc(6, GFP_KERNEL);
if(ret == NULL)
return NULL;
if (set_command_mode()) {
one = send_isa_command(CMD_ISA_VERSION_INTEGER);
ten = send_isa_command(CMD_ISA_VERSION_TENTH);
hund = send_isa_command(CMD_ISA_VERSION_HUNDRETH);
minor = send_isa_command(CMD_ISA_VERSION_MINOR);
sprintf(ret, "%c.%c%c%c", one, ten, hund, minor);
}
else
sprintf(ret, "ERROR");
unset_command_mode();
return(ret);
}
static inline int get_option_switches(void)
{
int rv=0;
if (set_command_mode()) {
/* Get switch settings */
rv = send_isa_command(CMD_ISA_SWITCH_SETTINGS);
}
unset_command_mode();
return(rv);
}
static int __devinit pcwatchdog_init(int base_addr)
{
int ret;
char *firmware;
int option_switches;
cards_found++;
if (cards_found == 1)
printk(KERN_INFO PFX "v%s Ken Hollis (kenji@bitgate.com)\n", WD_VER);
if (cards_found > 1) {
printk(KERN_ERR PFX "This driver only supports 1 device\n");
return -ENODEV;
}
if (base_addr == 0x0000) {
printk(KERN_ERR PFX "No I/O-Address for card detected\n");
return -ENODEV;
}
current_readport = base_addr;
/* Check card's revision */
revision = get_revision();
if (!request_region(current_readport, (revision == PCWD_REVISION_A) ? 2 : 4, "PCWD")) {
printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
current_readport);
current_readport = 0x0000;
return -EIO;
}
/* Initial variables */
supports_temp = 0;
temp_panic = 0;
initial_status = 0x0000;
/* get the boot_status */
pcwd_get_status(&initial_status);
/* clear the "card caused reboot" flag */
pcwd_clear_status();
init_timer(&timer);
timer.function = pcwd_timer_ping;
timer.data = 0;
/* Disable the board */
pcwd_stop();
/* Check whether or not the card supports the temperature device */
get_support();
/* Get some extra info from the hardware (in command/debug/diag mode) */
if (revision == PCWD_REVISION_A)
printk(KERN_INFO PFX "ISA-PC Watchdog (REV.A) detected at port 0x%04x\n", current_readport);
else if (revision == PCWD_REVISION_C) {
firmware = get_firmware();
printk(KERN_INFO PFX "ISA-PC Watchdog (REV.C) detected at port 0x%04x (Firmware version: %s)\n",
current_readport, firmware);
kfree(firmware);
option_switches = get_option_switches();
printk(KERN_INFO PFX "Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
option_switches,
((option_switches & 0x10) ? "ON" : "OFF"),
((option_switches & 0x08) ? "ON" : "OFF"));
/* Reprogram internal heartbeat to 2 seconds */
if (set_command_mode()) {
send_isa_command(CMD_ISA_DELAY_TIME_2SECS);
unset_command_mode();
}
} else {
/* Should NEVER happen, unless get_revision() fails. */
printk(KERN_INFO PFX "Unable to get revision\n");
release_region(current_readport, (revision == PCWD_REVISION_A) ? 2 : 4);
current_readport = 0x0000;
return -1;
}
if (supports_temp)
printk(KERN_INFO PFX "Temperature Option Detected\n");
if (initial_status & WDIOF_CARDRESET)
printk(KERN_INFO PFX "Previous reboot was caused by the card\n");
if (initial_status & WDIOF_OVERHEAT) {
printk(KERN_EMERG PFX "Card senses a CPU Overheat. Panicking!\n");
printk(KERN_EMERG PFX "CPU Overheat\n");
}
if (initial_status == 0)
printk(KERN_INFO PFX "No previous trip detected - Cold boot or reset\n");
/* Check that the heartbeat value is within it's range ; if not reset to the default */
if (pcwd_set_heartbeat(heartbeat)) {
pcwd_set_heartbeat(WATCHDOG_HEARTBEAT);
printk(KERN_INFO PFX "heartbeat value must be 2<=heartbeat<=7200, using %d\n",
WATCHDOG_HEARTBEAT);
}
ret = register_reboot_notifier(&pcwd_notifier);
if (ret) {
printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
ret);
release_region(current_readport, (revision == PCWD_REVISION_A) ? 2 : 4);
current_readport = 0x0000;
return ret;
}
if (supports_temp) {
ret = misc_register(&temp_miscdev);
if (ret) {
printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
TEMP_MINOR, ret);
unregister_reboot_notifier(&pcwd_notifier);
release_region(current_readport, (revision == PCWD_REVISION_A) ? 2 : 4);
current_readport = 0x0000;
return ret;
}
}
ret = misc_register(&pcwd_miscdev);
if (ret) {
printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
WATCHDOG_MINOR, ret);
if (supports_temp)
misc_deregister(&temp_miscdev);
unregister_reboot_notifier(&pcwd_notifier);
release_region(current_readport, (revision == PCWD_REVISION_A) ? 2 : 4);
current_readport = 0x0000;
return ret;
}
printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
heartbeat, nowayout);
return 0;
}
static void __devexit pcwatchdog_exit(void)
{
/* Disable the board */
if (!nowayout)
pcwd_stop();
/* Deregister */
misc_deregister(&pcwd_miscdev);
if (supports_temp)
misc_deregister(&temp_miscdev);
unregister_reboot_notifier(&pcwd_notifier);
release_region(current_readport, (revision == PCWD_REVISION_A) ? 2 : 4);
current_readport = 0x0000;
}
/*
* The ISA cards have a heartbeat bit in one of the registers, which
* register is card dependent. The heartbeat bit is monitored, and if
* found, is considered proof that a Berkshire card has been found.
* The initial rate is once per second at board start up, then twice
* per second for normal operation.
*/
static int __init pcwd_checkcard(int base_addr)
{
int port0, last_port0; /* Reg 0, in case it's REV A */
int port1, last_port1; /* Register 1 for REV C cards */
int i;
int retval;
if (!request_region (base_addr, 4, "PCWD")) {
printk (KERN_INFO PFX "Port 0x%04x unavailable\n", base_addr);
return 0;
}
retval = 0;
port0 = inb_p(base_addr); /* For REV A boards */
port1 = inb_p(base_addr + 1); /* For REV C boards */
if (port0 != 0xff || port1 != 0xff) {
/* Not an 'ff' from a floating bus, so must be a card! */
for (i = 0; i < 4; ++i) {
msleep(500);
last_port0 = port0;
last_port1 = port1;
port0 = inb_p(base_addr);
port1 = inb_p(base_addr + 1);
/* Has either hearbeat bit changed? */
if ((port0 ^ last_port0) & WD_HRTBT ||
(port1 ^ last_port1) & WD_REVC_HRBT) {
retval = 1;
break;
}
}
}
release_region (base_addr, 4);
return retval;
}
/*
* These are the auto-probe addresses available.
*
* Revision A only uses ports 0x270 and 0x370. Revision C introduced 0x350.
* Revision A has an address range of 2 addresses, while Revision C has 4.
*/
static int pcwd_ioports[] = { 0x270, 0x350, 0x370, 0x000 };
static int __init pcwd_init_module(void)
{
int i, found = 0;
spin_lock_init(&io_lock);
for (i = 0; pcwd_ioports[i] != 0; i++) {
if (pcwd_checkcard(pcwd_ioports[i])) {
if (!(pcwatchdog_init(pcwd_ioports[i])))
found++;
}
}
if (!found) {
printk (KERN_INFO PFX "No card detected, or port not available\n");
return -ENODEV;
}
return 0;
}
static void __exit pcwd_cleanup_module(void)
{
if (current_readport)
pcwatchdog_exit();
return;
}
module_init(pcwd_init_module);
module_exit(pcwd_cleanup_module);
MODULE_AUTHOR("Ken Hollis <kenji@bitgate.com>");
MODULE_DESCRIPTION("Berkshire ISA-PC Watchdog driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
MODULE_ALIAS_MISCDEV(TEMP_MINOR);