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path: root/drivers/char/watchdog/pcwd.c
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Diffstat (limited to 'drivers/char/watchdog/pcwd.c')
-rw-r--r--drivers/char/watchdog/pcwd.c926
1 files changed, 926 insertions, 0 deletions
diff --git a/drivers/char/watchdog/pcwd.c b/drivers/char/watchdog/pcwd.c
new file mode 100644
index 000000000000..592dca108866
--- /dev/null
+++ b/drivers/char/watchdog/pcwd.c
@@ -0,0 +1,926 @@
+/*
+ * 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 <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) ")");
+
+#ifdef CONFIG_WATCHDOG_NOWAYOUT
+static int nowayout = 1;
+#else
+static int nowayout = 0;
+#endif
+
+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");
+ machine_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");
+ machine_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);