// SPDX-License-Identifier: GPL-2.0-only
/*
* PC Watchdog Driver
* by Ken Hollis ([email protected])
*
* Permission granted from Simon Machell ([email protected])
* 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 <[email protected]>.
* 980112 Used minor numbers from include/linux/miscdevice.h
* 990403 Clear reset status after reading control status register in
* pcwd_showprevstate(). [Marc Boucher <[email protected]>]
* 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 <[email protected]>
* 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/
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h> /* For module specific items */
#include <linux/moduleparam.h> /* For new moduleparam's */
#include <linux/types.h> /* For standard types (like size_t) */
#include <linux/errno.h> /* For the -ENODEV/... values */
#include <linux/kernel.h> /* For printk/panic/... */
#include <linux/delay.h> /* For mdelay function */
#include <linux/timer.h> /* For timer related operations */
#include <linux/jiffies.h> /* For jiffies stuff */
#include <linux/miscdevice.h> /* For struct miscdevice */
#include <linux/watchdog.h> /* For the watchdog specific items */
#include <linux/reboot.h> /* For kernel_power_off() */
#include <linux/init.h> /* For __init/__exit/... */
#include <linux/fs.h> /* For file operations */
#include <linux/isa.h> /* For isa devices */
#include <linux/ioport.h> /* For io-port access */
#include <linux/spinlock.h> /* For spin_lock/spin_unlock/... */
#include <linux/uaccess.h> /* For copy_to_user/put_user/... */
#include <linux/io.h> /* For inb/outb/... */
/* Module and version information */
#define WATCHDOG_VERSION "1.20"
#define WATCHDOG_DATE "18 Feb 2007"
#define WATCHDOG_DRIVER_NAME "ISA-PC Watchdog"
#define WATCHDOG_NAME "pcwd"
#define DRIVER_VERSION WATCHDOG_DRIVER_NAME " driver, v" WATCHDOG_VERSION "\n"
/*
* 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 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.
*/
#define PCWD_ISA_NR_CARDS 3
static int pcwd_ioports[] = { 0x270, 0x350, 0x370, 0x000 };
/*
* These are the defines that describe the control status bits for the
* PCI-PC Watchdog card.
*/
/* Port 1 : Control Status #1 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 */
/* Port 1 : Control Status #1 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 */
#define WD_REVC_RL2A 0x08 /* Relay 2 activated by
on-board processor */
#define WD_REVC_RL1A 0x10 /* Relay 1 active */
#define WD_REVC_R2DS 0x40 /* Relay 2 disable */
#define WD_REVC_RLY2 0x80 /* Relay 2 activated? */
/* Port 2 : Control Status #2 */
#define WD_WDIS 0x10 /* Watchdog Disabled */
#define WD_ENTP 0x20 /* Watchdog Enable Temperature Trip */
#define WD_SSEL 0x40 /* Watchdog Switch Select
(1:SW1 <-> 0:SW2) */
#define WD_WCMD 0x80 /* Watchdog Command Mode */
/* 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_RESET_PC 0x06
#define CMD_ISA_ARM_0 0x07
#define CMD_ISA_ARM_30 0x08
#define CMD_ISA_ARM_60 0x09
#define CMD_ISA_DELAY_TIME_2SECS 0x0A
#define CMD_ISA_DELAY_TIME_4SECS 0x0B
#define CMD_ISA_DELAY_TIME_8SECS 0x0C
#define CMD_ISA_RESET_RELAYS 0x0D
/* Watchdog's Dip Switch heartbeat values */
static const int heartbeat_tbl[] = {
20, /* OFF-OFF-OFF = 20 Sec */
40, /* OFF-OFF-ON = 40 Sec */
60, /* OFF-ON-OFF = 1 Min */
300, /* OFF-ON-ON = 5 Min */
600, /* ON-OFF-OFF = 10 Min */
1800, /* ON-OFF-ON = 30 Min */
3600, /* ON-ON-OFF = 1 Hour */
7200, /* ON-ON-ON = 2 hour */
};
/*
* 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 unsigned long open_allowed;
static char expect_close;
static int temp_panic;
/* this is private data for each ISA-PC watchdog card */
static struct {
char fw_ver_str[6]; /* The cards firmware version */
int revision; /* The card's revision */
int supports_temp; /* Whether or not the card has
a temperature device */
int command_mode; /* Whether or not the card is in
command mode */
int boot_status; /* The card's boot status */
int io_addr; /* The cards I/O address */
spinlock_t io_lock; /* the lock for io operations */
struct timer_list timer; /* The timer that pings the watchdog */
unsigned long next_heartbeat; /* the next_heartbeat for the timer */
} pcwd_private;
/* module parameters */
#define QUIET 0 /* Default */
#define VERBOSE 1 /* Verbose */
#define DEBUG 2 /* print fancy stuff too */
static int debug = QUIET;
module_param(debug, int, 0);
MODULE_PARM_DESC(debug,
"Debug level: 0=Quiet, 1=Verbose, 2=Debug (default=0)");
/* default heartbeat = delay-time from dip-switches */
#define WATCHDOG_HEARTBEAT 0
static int heartbeat = WATCHDOG_HEARTBEAT;
module_param(heartbeat, int, 0);
MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. "
"(2 <= heartbeat <= 7200 or 0=delay-time from dip-switches, default="
__MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout,
"Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
/*
* Internal functions
*/
static int send_isa_command(int cmd)
{
int i;
int control_status;
int port0, last_port0; /* Double read for stabilising */
if (debug >= DEBUG)
pr_debug("sending following data cmd=0x%02x\n", cmd);
/* The WCMD bit must be 1 and the command is only 4 bits in size */
control_status = (cmd & 0x0F) | WD_WCMD;
outb_p(control_status, pcwd_private.io_addr + 2);
udelay(ISA_COMMAND_TIMEOUT);
port0 = inb_p(pcwd_private.io_addr);
for (i = 0; i < 25; ++i) {
last_port0 = port0;
port0 = inb_p(pcwd_private.io_addr);
if (port0 == last_port0)
break; /* Data is stable */
udelay(250);
}
if (debug >= DEBUG)
pr_debug("received following data for cmd=0x%02x: port0=0x%02x last_port0=0x%02x\n",
cmd, port0, last_port0);
return port0;
}
static int set_command_mode(void)
{
int i, found = 0, count = 0;
/* Set the card into command mode */
spin_lock(&pcwd_private.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, pcwd_private.io_addr + 2);
udelay(1200); /* Spec says wait 1ms */
outb_p(0x00, pcwd_private.io_addr + 2);
udelay(ISA_COMMAND_TIMEOUT);
}
count++;
}
spin_unlock(&pcwd_private.io_lock);
pcwd_private.command_mode = found;
if (debug >= DEBUG)
pr_debug("command_mode=%d\n", pcwd_private.command_mode);
return found;
}
static void unset_command_mode(void)
{
/* Set the card into normal mode */
spin_lock(&pcwd_private.io_lock);
outb_p(0x00, pcwd_private.io_addr + 2);
udelay(ISA_COMMAND_TIMEOUT);
spin_unlock(&pcwd_private.io_lock);
pcwd_private.command_mode = 0;
if (debug >= DEBUG)
pr_debug("command_mode=%d\n", pcwd_private.command_mode);
}
static inline void pcwd_check_temperature_support(void)
{
if (inb(pcwd_private.io_addr) != 0xF0)
pcwd_private.supports_temp = 1;
}
static inline void pcwd_get_firmware(void)
{
int one, ten, hund, minor;
strcpy(pcwd_private.fw_ver_str, "ERROR");
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(pcwd_private.fw_ver_str, "%c.%c%c%c",
one, ten, hund, minor);
}
unset_command_mode();
return;
}
static inline int pcwd_get_option_switches(void)
{
int option_switches = 0;
if (set_command_mode()) {
/* Get switch settings */
option_switches = send_isa_command(CMD_ISA_SWITCH_SETTINGS);
}
unset_command_mode();
return option_switches;
}
static void pcwd_show_card_info(void)
{
int option_switches;
/* Get some extra info from the hardware (in command/debug/diag mode) */
if (pcwd_private.revision == PCWD_REVISION_A)
pr_info("ISA-PC Watchdog (REV.A) detected at port 0x%04x\n",
pcwd_private.io_addr);
else if (pcwd_private.revision == PCWD_REVISION_C) {
pcwd_get_firmware();
pr_info("ISA-PC Watchdog (REV.C) detected at port 0x%04x (Firmware version: %s)\n",
pcwd_private.io_addr, pcwd_private.fw_ver_str);
option_switches = pcwd_get_option_switches();
pr_info("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();
}
}
if (pcwd_private.supports_temp)
pr_info("Temperature Option Detected\n");
if (pcwd_private.boot_status & WDIOF_CARDRESET)
pr_info("Previous reboot was caused by the card\n");
if (pcwd_private.boot_status & WDIOF_OVERHEAT) {
pr_emerg("Card senses a CPU Overheat. Panicking!\n");
pr_emerg("CPU Overheat\n");
}
if (pcwd_private.boot_status == 0)
pr_info("No previous trip detected - Cold boot or reset\n");
}
static void pcwd_timer_ping(struct timer_list *unused)
{
int wdrst_stat;
/* If we got a heartbeat pulse within the WDT_INTERVAL
* we agree to ping the WDT */
if (time_before(jiffies, pcwd_private.next_heartbeat)) {
/* Ping the watchdog */
spin_lock(&pcwd_private.io_lock);
if (pcwd_private.revision == PCWD_REVISION_A) {
/* Rev A cards are reset by setting the
WD_WDRST bit in register 1 */
wdrst_stat = inb_p(pcwd_private.io_addr);
wdrst_stat &= 0x0F;
wdrst_stat |= WD_WDRST;
outb_p(wdrst_stat, pcwd_private.io_addr + 1);
} else {
/* Re-trigger watchdog by writing to port 0 */
outb_p(0x00, pcwd_private.io_addr);
}
/* Re-set the timer interval */
mod_timer(&pcwd_private.timer, jiffies + WDT_INTERVAL);
spin_unlock(&pcwd_private.io_lock);
} else {
pr_warn("Heartbeat lost! Will not ping the watchdog\n");
}
}
static int pcwd_start(void)
{
int stat_reg;
pcwd_private.next_heartbeat = jiffies + (heartbeat * HZ);
/* Start the timer */
mod_timer(&pcwd_private.timer, jiffies + WDT_INTERVAL);
/* Enable the port */
if (pcwd_private.revision == PCWD_REVISION_C) {
spin_lock(&pcwd_private.io_lock);
outb_p(0x00, pcwd_private.io_addr + 3);
udelay(ISA_COMMAND_TIMEOUT);
stat_reg = inb_p(pcwd_private.io_addr + 2);
spin_unlock(&pcwd_private.io_lock);
if (stat_reg & WD_WDIS) {
pr_info("Could not start watchdog\n");
return -EIO;
}
}
if (debug >= VERBOSE)
pr_debug("Watchdog started\n");
return 0;
}
static int pcwd_stop(void)
{
int stat_reg;
/* Stop the timer */
del_timer(&pcwd_private.timer);
/* Disable the board */
if (pcwd_private.revision == PCWD_REVISION_C) {
spin_lock(&pcwd_private.io_lock);
outb_p(0xA5, pcwd_private.io_addr + 3);
udelay(ISA_COMMAND_TIMEOUT);
outb_p(0xA5, pcwd_private.io_addr + 3);
udelay(ISA_COMMAND_TIMEOUT);
stat_reg = inb_p(pcwd_private.io_addr + 2);
spin_unlock(&pcwd_private.io_lock);
if ((stat_reg & WD_WDIS) == 0) {
pr_info("Could not stop watchdog\n");
return -EIO;
}
}
if (debug >= VERBOSE)
pr_debug("Watchdog stopped\n");
return 0;
}
static int pcwd_keepalive(void)
{
/* user land ping */
pcwd_private.next_heartbeat = jiffies + (heartbeat * HZ);
if (debug >= DEBUG)
pr_debug("Watchdog keepalive signal send\n");
return 0;
}
static int pcwd_set_heartbeat(int t)
{
if (t < 2 || t > 7200) /* arbitrary upper limit */
return -EINVAL;
heartbeat = t;
if (debug >= VERBOSE)
pr_debug("New heartbeat: %d\n", heartbeat);
return 0;
}
static int pcwd_get_status(int *status)
{
int control_status;
*status = 0;
spin_lock(&pcwd_private.io_lock);
if (pcwd_private.revision == PCWD_REVISION_A)
/* Rev A cards return status information from
* the base register, which is used for the
* temperature in other cards. */
control_status = inb(pcwd_private.io_addr);
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. */
control_status = inb(pcwd_private.io_addr + 1);
}
spin_unlock(&pcwd_private.io_lock);
if (pcwd_private.revision == PCWD_REVISION_A) {
if (control_status & WD_WDRST)
*status |= WDIOF_CARDRESET;
if (control_status & WD_T110) {
*status |= WDIOF_OVERHEAT;
if (temp_panic) {
pr_info("Temperature overheat trip!\n");
kernel_power_off();
}
}
} else {
if (control_status & WD_REVC_WTRP)
*status |= WDIOF_CARDRESET;
if (control_status & WD_REVC_TTRP) {
*status |= WDIOF_OVERHEAT;
if (temp_panic) {
pr_info("Temperature overheat trip!\n");
kernel_power_off();
}
}
}
return 0;
}
static int pcwd_clear_status(void)
{
int control_status;
if (pcwd_private.revision == PCWD_REVISION_C) {
spin_lock(&pcwd_private.io_lock);
if (debug >= VERBOSE)
pr_info("clearing watchdog trip status\n");
control_status = inb_p(pcwd_private.io_addr + 1);
if (debug >= DEBUG) {
pr_debug("status was: 0x%02x\n", control_status);
pr_debug("sending: 0x%02x\n",
(control_status & WD_REVC_R2DS));
}
/* clear reset status & Keep Relay 2 disable state as it is */
outb_p((control_status & WD_REVC_R2DS),
pcwd_private.io_addr + 1);
spin_unlock(&pcwd_private.io_lock);
}
return 0;
}
static int pcwd_get_temperature(int *temperature)
{
/* check that port 0 gives temperature info and no command results */
if (pcwd_private.command_mode)
return -1;
*temperature = 0;
if (!pcwd_private.supports_temp)
return -ENODEV;
/*
* Convert celsius to fahrenheit, since this was
* the decided 'standard' for this return value.
*/
spin_lock(&pcwd_private.io_lock);
*temperature = ((inb(pcwd_private.io_addr)) * 9 / 5) + 32;
spin_unlock(&pcwd_private.io_lock);
if (debug >= DEBUG) {
pr_debug("temperature is: %d F\n", *temperature);
}
return 0;
}
/*
* /dev/watchdog handling
*/
static long pcwd_ioctl(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 const struct watchdog_info ident = {
.options = WDIOF_OVERHEAT |
WDIOF_CARDRESET |
WDIOF_KEEPALIVEPING |
WDIOF_SETTIMEOUT |
WDIOF_MAGICCLOSE,
.firmware_version = 1,
.identity = "PCWD",
};
switch (cmd) {
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(pcwd_private.boot_status, argp);
case WDIOC_GETTEMP:
if (pcwd_get_temperature(&temperature))
return -EFAULT;
return put_user(temperature, argp);
case WDIOC_SETOPTIONS:
if (pcwd_private.revision == PCWD_REVISION_C) {
if (get_user(rv, argp))
return -EFAULT;
if (rv & WDIOS_DISABLECARD) {
status = pcwd_stop();
if (status < 0)
return status;
}
if (rv & WDIOS_ENABLECARD) {
status = pcwd_start();
if (status < 0)
return status;
}
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();
fallthrough;
case WDIOC_GETTIMEOUT:
return put_user(heartbeat, argp);
default:
return -ENOTTY;
}
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 (test_and_set_bit(0, &open_allowed))
return -EBUSY;
if (nowayout)
__module_get(THIS_MODULE);
/* Activate */
pcwd_start();
pcwd_keepalive();
return stream_open(inode, file);
}
static int pcwd_close(struct inode *inode, struct file *file)
{
if (expect_close == 42)
pcwd_stop();
else {
pr_crit("Unexpected close, not stopping watchdog!\n");
pcwd_keepalive();
}
expect_close = 0;
clear_bit(0, &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 (!pcwd_private.supports_temp)
return -ENODEV;
return stream_open(inode, file);
}
static int pcwd_temp_close(struct inode *inode, struct file *file)
{
return 0;
}
/*
* Kernel Interfaces
*/
static const struct file_operations pcwd_fops = {
.owner = THIS_MODULE,
.write = pcwd_write,
.unlocked_ioctl = pcwd_ioctl,
.compat_ioctl = compat_ptr_ioctl,
.open = pcwd_open,
.release = pcwd_close,
};
static struct miscdevice pcwd_miscdev = {
.minor = WATCHDOG_MINOR,
.name = "watchdog",
.fops = &pcwd_fops,
};
static const struct file_operations pcwd_temp_fops = {
.owner = THIS_MODULE,
.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,
};
/*
* Init & exit routines
*/
static inline int get_revision(void)
{
int r = PCWD_REVISION_C;
spin_lock(&pcwd_private.io_lock);
/* REV A cards use only 2 io ports; test
* presumes a floating bus reads as 0xff. */
if ((inb(pcwd_private.io_addr + 2) == 0xFF) ||
(inb(pcwd_private.io_addr + 3) == 0xFF))
r = PCWD_REVISION_A;
spin_unlock(&pcwd_private.io_lock);
return r;
}
/*
* 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 pcwd_isa_match(struct device *dev, unsigned int id)
{
int base_addr = pcwd_ioports[id];
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 (debug >= DEBUG)
pr_debug("pcwd_isa_match id=%d\n", id);
if (!request_region(base_addr, 4, "PCWD")) {
pr_info("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;
}
static int pcwd_isa_probe(struct device *dev, unsigned int id)
{
int ret;
if (debug >= DEBUG)
pr_debug("pcwd_isa_probe id=%d\n", id);
cards_found++;
if (cards_found == 1)
pr_info("v%s Ken Hollis ([email protected])\n",
WATCHDOG_VERSION);
if (cards_found > 1) {
pr_err("This driver only supports 1 device\n");
return -ENODEV;
}
if (pcwd_ioports[id] == 0x0000) {
pr_err("No I/O-Address for card detected\n");
return -ENODEV;
}
pcwd_private.io_addr = pcwd_ioports[id];
spin_lock_init(&pcwd_private.io_lock);
/* Check card's revision */
pcwd_private.revision = get_revision();
if (!request_region(pcwd_private.io_addr,
(pcwd_private.revision == PCWD_REVISION_A) ? 2 : 4, "PCWD")) {
pr_err("I/O address 0x%04x already in use\n",
pcwd_private.io_addr);
ret = -EIO;
goto error_request_region;
}
/* Initial variables */
pcwd_private.supports_temp = 0;
temp_panic = 0;
pcwd_private.boot_status = 0x0000;
/* get the boot_status */
pcwd_get_status(&pcwd_private.boot_status);
/* clear the "card caused reboot" flag */
pcwd_clear_status();
timer_setup(&pcwd_private.timer, pcwd_timer_ping, 0);
/* Disable the board */
pcwd_stop();
/* Check whether or not the card supports the temperature device */
pcwd_check_temperature_support();
/* Show info about the card itself */
pcwd_show_card_info();
/* If heartbeat = 0 then we use the heartbeat from the dip-switches */
if (heartbeat == 0)
heartbeat = heartbeat_tbl[(pcwd_get_option_switches() & 0x07)];
/* 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);
pr_info("heartbeat value must be 2 <= heartbeat <= 7200, using %d\n",
WATCHDOG_HEARTBEAT);
}
if (pcwd_private.supports_temp) {
ret = misc_register(&temp_miscdev);
if (ret) {
pr_err("cannot register miscdev on minor=%d (err=%d)\n",
TEMP_MINOR, ret);
goto error_misc_register_temp;
}
}
ret = misc_register(&pcwd_miscdev);
if (ret) {
pr_err("cannot register miscdev on minor=%d (err=%d)\n",
WATCHDOG_MINOR, ret);
goto error_misc_register_watchdog;
}
pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
heartbeat, nowayout);
return 0;
error_misc_register_watchdog:
if (pcwd_private.supports_temp)
misc_deregister(&temp_miscdev);
error_misc_register_temp:
release_region(pcwd_private.io_addr,
(pcwd_private.revision == PCWD_REVISION_A) ? 2 : 4);
error_request_region:
pcwd_private.io_addr = 0x0000;
cards_found--;
return ret;
}
static void pcwd_isa_remove(struct device *dev, unsigned int id)
{
if (debug >= DEBUG)
pr_debug("pcwd_isa_remove id=%d\n", id);
/* Disable the board */
if (!nowayout)
pcwd_stop();
/* Deregister */
misc_deregister(&pcwd_miscdev);
if (pcwd_private.supports_temp)
misc_deregister(&temp_miscdev);
release_region(pcwd_private.io_addr,
(pcwd_private.revision == PCWD_REVISION_A) ? 2 : 4);
pcwd_private.io_addr = 0x0000;
cards_found--;
}
static void pcwd_isa_shutdown(struct device *dev, unsigned int id)
{
if (debug >= DEBUG)
pr_debug("pcwd_isa_shutdown id=%d\n", id);
pcwd_stop();
}
static struct isa_driver pcwd_isa_driver = {
.match = pcwd_isa_match,
.probe = pcwd_isa_probe,
.remove = pcwd_isa_remove,
.shutdown = pcwd_isa_shutdown,
.driver = {
.owner = THIS_MODULE,
.name = WATCHDOG_NAME,
},
};
module_isa_driver(pcwd_isa_driver, PCWD_ISA_NR_CARDS);
MODULE_AUTHOR("Ken Hollis <[email protected]>, "
"Wim Van Sebroeck <[email protected]>");
MODULE_DESCRIPTION("Berkshire ISA-PC Watchdog driver");
MODULE_VERSION(WATCHDOG_VERSION);
MODULE_LICENSE("GPL");
Codebase Browser
linux