Linux-2.6.12-rc2

[linux-2.6/next.git] / drivers / char / watchdog / pcwd_pci.c

/*
 *      Berkshire PCI-PC Watchdog Card Driver
 *
 *      (c) Copyright 2003 Wim Van Sebroeck <wim@iguana.be>.
 *
 *      Based on source code of the following authors:
 *        Ken Hollis <kenji@bitgate.com>,
 *        Lindsay Harris <lindsay@bluegum.com>,
 *        Alan Cox <alan@redhat.com>,
 *        Matt Domsch <Matt_Domsch@dell.com>,
 *        Rob Radez <rob@osinvestor.com>
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 *
 *      Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
 *      provide warranty for any of this software. This material is
 *      provided "AS-IS" and at no charge.
 */

/*
 *      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/
 */

/*
 *      Includes, defines, variables, module parameters, ...
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/delay.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/notifier.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/pci.h>
#include <linux/ioport.h>
#include <linux/spinlock.h>

#include <asm/uaccess.h>
#include <asm/io.h>

/* Module and version information */
#define WATCHDOG_VERSION "1.01"
#define WATCHDOG_DATE "15 Mar 2005"
#define WATCHDOG_DRIVER_NAME "PCI-PC Watchdog"
#define WATCHDOG_NAME "pcwd_pci"
#define PFX WATCHDOG_NAME ": "
#define DRIVER_VERSION WATCHDOG_DRIVER_NAME " driver, v" WATCHDOG_VERSION " (" WATCHDOG_DATE ")\n"

/* Stuff for the PCI ID's  */
#ifndef PCI_VENDOR_ID_QUICKLOGIC
#define PCI_VENDOR_ID_QUICKLOGIC    0x11e3
#endif

#ifndef PCI_DEVICE_ID_WATCHDOG_PCIPCWD
#define PCI_DEVICE_ID_WATCHDOG_PCIPCWD 0x5030
#endif

/*
 * These are the defines that describe the control status bits for the
 * PCI-PC Watchdog card.
 */
#define WD_PCI_WTRP             0x01    /* Watchdog Trip status */
#define WD_PCI_HRBT             0x02    /* Watchdog Heartbeat */
#define WD_PCI_TTRP             0x04    /* Temperature Trip status */

/* according to documentation max. time to process a command for the pci
 * watchdog card is 100 ms, so we give it 150 ms to do it's job */
#define PCI_COMMAND_TIMEOUT     150

/* Watchdog's internal commands */
#define CMD_GET_STATUS                  0x04
#define CMD_GET_FIRMWARE_VERSION        0x08
#define CMD_READ_WATCHDOG_TIMEOUT       0x18
#define CMD_WRITE_WATCHDOG_TIMEOUT      0x19

/* We can only use 1 card due to the /dev/watchdog restriction */
static int cards_found;

/* internal variables */
static int temp_panic;
static unsigned long is_active;
static char expect_release;
static struct {
        int supports_temp;      /* Wether or not the card has a temperature device */
        int boot_status;        /* The card's boot status */
        unsigned long io_addr;  /* The cards I/O address */
        spinlock_t io_lock;
        struct pci_dev *pdev;
} pcipcwd_private;

/* module parameters */
#define WATCHDOG_HEARTBEAT 2    /* 2 sec default heartbeat */
static int heartbeat = WATCHDOG_HEARTBEAT;
module_param(heartbeat, int, 0);
MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (0<heartbeat<65536, 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_command(int cmd, int *msb, int *lsb)
{
        int got_response, count;

        spin_lock(&pcipcwd_private.io_lock);
        /* If a command requires data it should be written first.
         * Data for commands with 8 bits of data should be written to port 4.
         * Commands with 16 bits of data, should be written as LSB to port 4
         * and MSB to port 5.
         * After the required data has been written then write the command to
         * port 6. */
        outb_p(*lsb, pcipcwd_private.io_addr + 4);
        outb_p(*msb, pcipcwd_private.io_addr + 5);
        outb_p(cmd, pcipcwd_private.io_addr + 6);

        /* wait till the pci card processed the command, signaled by
         * the WRSP bit in port 2 and give it a max. timeout of
         * PCI_COMMAND_TIMEOUT to process */
        got_response = inb_p(pcipcwd_private.io_addr + 2) & 0x40;
        for (count = 0; (count < PCI_COMMAND_TIMEOUT) && (!got_response); count++) {
                mdelay(1);
                got_response = inb_p(pcipcwd_private.io_addr + 2) & 0x40;
        }

        if (got_response) {
                /* read back response */
                *lsb = inb_p(pcipcwd_private.io_addr + 4);
                *msb = inb_p(pcipcwd_private.io_addr + 5);

                /* clear WRSP bit */
                inb_p(pcipcwd_private.io_addr + 6);
        }
        spin_unlock(&pcipcwd_private.io_lock);

        return got_response;
}

static int pcipcwd_start(void)
{
        int stat_reg;

        spin_lock(&pcipcwd_private.io_lock);
        outb_p(0x00, pcipcwd_private.io_addr + 3);
        udelay(1000);

        stat_reg = inb_p(pcipcwd_private.io_addr + 2);
        spin_unlock(&pcipcwd_private.io_lock);

        if (stat_reg & 0x10) {
                printk(KERN_ERR PFX "Card timer not enabled\n");
                return -1;
        }

        return 0;
}

static int pcipcwd_stop(void)
{
        int stat_reg;

        spin_lock(&pcipcwd_private.io_lock);
        outb_p(0xA5, pcipcwd_private.io_addr + 3);
        udelay(1000);

        outb_p(0xA5, pcipcwd_private.io_addr + 3);
        udelay(1000);

        stat_reg = inb_p(pcipcwd_private.io_addr + 2);
        spin_unlock(&pcipcwd_private.io_lock);

        if (!(stat_reg & 0x10)) {
                printk(KERN_ERR PFX "Card did not acknowledge disable attempt\n");
                return -1;
        }

        return 0;
}

static int pcipcwd_keepalive(void)
{
        /* Re-trigger watchdog by writing to port 0 */
        outb_p(0x42, pcipcwd_private.io_addr);
        return 0;
}

static int pcipcwd_set_heartbeat(int t)
{
        int t_msb = t / 256;
        int t_lsb = t % 256;

        if ((t < 0x0001) || (t > 0xFFFF))
                return -EINVAL;

        /* Write new heartbeat to watchdog */
        send_command(CMD_WRITE_WATCHDOG_TIMEOUT, &t_msb, &t_lsb);

        heartbeat = t;
        return 0;
}

static int pcipcwd_get_status(int *status)
{
        int new_status;

        *status=0;
        new_status = inb_p(pcipcwd_private.io_addr + 1);
        if (new_status & WD_PCI_WTRP)
                *status |= WDIOF_CARDRESET;
        if (new_status & WD_PCI_TTRP) {
                *status |= WDIOF_OVERHEAT;
                if (temp_panic)
                        panic(PFX "Temperature overheat trip!\n");
        }

        return 0;
}

static int pcipcwd_clear_status(void)
{
        outb_p(0x01, pcipcwd_private.io_addr + 1);
        return 0;
}

static int pcipcwd_get_temperature(int *temperature)
{
        *temperature = 0;
        if (!pcipcwd_private.supports_temp)
                return -ENODEV;

        /*
         * Convert celsius to fahrenheit, since this was
         * the decided 'standard' for this return value.
         */
        *temperature = ((inb_p(pcipcwd_private.io_addr)) * 9 / 5) + 32;

        return 0;
}

/*
 *      /dev/watchdog handling
 */

static ssize_t pcipcwd_write(struct file *file, const char __user *data,
                              size_t len, loff_t *ppos)
{
        /* See if we got the magic character 'V' and reload the timer */
        if (len) {
                if (!nowayout) {
                        size_t i;

                        /* note: just in case someone wrote the magic character
                         * five months ago... */
                        expect_release = 0;

                        /* scan to see whether or not we got the magic character */
                        for (i = 0; i != len; i++) {
                                char c;
                                if(get_user(c, data+i))
                                        return -EFAULT;
                                if (c == 'V')
                                        expect_release = 42;
                        }
                }

                /* someone wrote to us, we should reload the timer */
                pcipcwd_keepalive();
        }
        return len;
}

static int pcipcwd_ioctl(struct inode *inode, struct file *file,
                          unsigned int cmd, unsigned long arg)
{
        void __user *argp = (void __user *)arg;
        int __user *p = argp;
        static struct watchdog_info ident = {
                .options =              WDIOF_OVERHEAT |
                                        WDIOF_CARDRESET |
                                        WDIOF_KEEPALIVEPING |
                                        WDIOF_SETTIMEOUT |
                                        WDIOF_MAGICCLOSE,
                .firmware_version =     1,
                .identity =             WATCHDOG_DRIVER_NAME,
        };

        switch (cmd) {
                case WDIOC_GETSUPPORT:
                        return copy_to_user(argp, &ident,
                                sizeof (ident)) ? -EFAULT : 0;

                case WDIOC_GETSTATUS:
                {
                        int status;

                        pcipcwd_get_status(&status);

                        return put_user(status, p);
                }

                case WDIOC_GETBOOTSTATUS:
                        return put_user(pcipcwd_private.boot_status, p);

                case WDIOC_GETTEMP:
                {
                        int temperature;

                        if (pcipcwd_get_temperature(&temperature))
                                return -EFAULT;

                        return put_user(temperature, p);
                }

                case WDIOC_KEEPALIVE:
                        pcipcwd_keepalive();
                        return 0;

                case WDIOC_SETOPTIONS:
                {
                        int new_options, retval = -EINVAL;

                        if (get_user (new_options, p))
                                return -EFAULT;

                        if (new_options & WDIOS_DISABLECARD) {
                                pcipcwd_stop();
                                retval = 0;
                        }

                        if (new_options & WDIOS_ENABLECARD) {
                                pcipcwd_start();
                                retval = 0;
                        }

                        if (new_options & WDIOS_TEMPPANIC) {
                                temp_panic = 1;
                                retval = 0;
                        }

                        return retval;
                }

                case WDIOC_SETTIMEOUT:
                {
                        int new_heartbeat;

                        if (get_user(new_heartbeat, p))
                                return -EFAULT;

                        if (pcipcwd_set_heartbeat(new_heartbeat))
                            return -EINVAL;

                        pcipcwd_keepalive();
                        /* Fall */
                }

                case WDIOC_GETTIMEOUT:
                        return put_user(heartbeat, p);

                default:
                        return -ENOIOCTLCMD;
        }
}

static int pcipcwd_open(struct inode *inode, struct file *file)
{
        /* /dev/watchdog can only be opened once */
        if (test_and_set_bit(0, &is_active))
                return -EBUSY;

        /* Activate */
        pcipcwd_start();
        pcipcwd_keepalive();
        return nonseekable_open(inode, file);
}

static int pcipcwd_release(struct inode *inode, struct file *file)
{
        /*
         *      Shut off the timer.
         */
        if (expect_release == 42) {
                pcipcwd_stop();
        } else {
                printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
                pcipcwd_keepalive();
        }
        expect_release = 0;
        clear_bit(0, &is_active);
        return 0;
}

/*
 *      /dev/temperature handling
 */

static ssize_t pcipcwd_temp_read(struct file *file, char __user *data,
                                size_t len, loff_t *ppos)
{
        int temperature;

        if (pcipcwd_get_temperature(&temperature))
                return -EFAULT;

        if (copy_to_user (data, &temperature, 1))
                return -EFAULT;

        return 1;
}

static int pcipcwd_temp_open(struct inode *inode, struct file *file)
{
        if (!pcipcwd_private.supports_temp)
                return -ENODEV;

        return nonseekable_open(inode, file);
}

static int pcipcwd_temp_release(struct inode *inode, struct file *file)
{
        return 0;
}

/*
 *      Notify system
 */

static int pcipcwd_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
{
        if (code==SYS_DOWN || code==SYS_HALT) {
                /* Turn the WDT off */
                pcipcwd_stop();
        }

        return NOTIFY_DONE;
}

/*
 *      Kernel Interfaces
 */

static struct file_operations pcipcwd_fops = {
        .owner =        THIS_MODULE,
        .llseek =       no_llseek,
        .write =        pcipcwd_write,
        .ioctl =        pcipcwd_ioctl,
        .open =         pcipcwd_open,
        .release =      pcipcwd_release,
};

static struct miscdevice pcipcwd_miscdev = {
        .minor =        WATCHDOG_MINOR,
        .name =         "watchdog",
        .fops =         &pcipcwd_fops,
};

static struct file_operations pcipcwd_temp_fops = {
        .owner =        THIS_MODULE,
        .llseek =       no_llseek,
        .read =         pcipcwd_temp_read,
        .open =         pcipcwd_temp_open,
        .release =      pcipcwd_temp_release,
};

static struct miscdevice pcipcwd_temp_miscdev = {
        .minor =        TEMP_MINOR,
        .name =         "temperature",
        .fops =         &pcipcwd_temp_fops,
};

static struct notifier_block pcipcwd_notifier = {
        .notifier_call =        pcipcwd_notify_sys,
};

/*
 *      Init & exit routines
 */

static inline void check_temperature_support(void)
{
        if (inb_p(pcipcwd_private.io_addr) != 0xF0)
                pcipcwd_private.supports_temp = 1;
}

static int __devinit pcipcwd_card_init(struct pci_dev *pdev,
                const struct pci_device_id *ent)
{
        int ret = -EIO;
        int got_fw_rev, fw_rev_major, fw_rev_minor;
        char fw_ver_str[20];
        char option_switches;

        cards_found++;
        if (cards_found == 1)
                printk(KERN_INFO PFX DRIVER_VERSION);

        if (cards_found > 1) {
                printk(KERN_ERR PFX "This driver only supports 1 device\n");
                return -ENODEV;
        }

        if (pci_enable_device(pdev)) {
                printk(KERN_ERR PFX "Not possible to enable PCI Device\n");
                return -ENODEV;
        }

        if (pci_resource_start(pdev, 0) == 0x0000) {
                printk(KERN_ERR PFX "No I/O-Address for card detected\n");
                ret = -ENODEV;
                goto err_out_disable_device;
        }

        pcipcwd_private.pdev = pdev;
        pcipcwd_private.io_addr = pci_resource_start(pdev, 0);

        if (pci_request_regions(pdev, WATCHDOG_NAME)) {
                printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
                        (int) pcipcwd_private.io_addr);
                ret = -EIO;
                goto err_out_disable_device;
        }

        /* get the boot_status */
        pcipcwd_get_status(&pcipcwd_private.boot_status);

        /* clear the "card caused reboot" flag */
        pcipcwd_clear_status();

        /* disable card */
        pcipcwd_stop();

        /* Check whether or not the card supports the temperature device */
        check_temperature_support();

        /* Get the Firmware Version */
        got_fw_rev = send_command(CMD_GET_FIRMWARE_VERSION, &fw_rev_major, &fw_rev_minor);
        if (got_fw_rev) {
                sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
        } else {
                sprintf(fw_ver_str, "<card no answer>");
        }

        /* Get switch settings */
        option_switches = inb_p(pcipcwd_private.io_addr + 3);

        printk(KERN_INFO PFX "Found card at port 0x%04x (Firmware: %s) %s temp option\n",
                (int) pcipcwd_private.io_addr, fw_ver_str,
                (pcipcwd_private.supports_temp ? "with" : "without"));

        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"));

        if (pcipcwd_private.boot_status & WDIOF_CARDRESET)
                printk(KERN_INFO PFX "Previous reset was caused by the Watchdog card\n");

        if (pcipcwd_private.boot_status & WDIOF_OVERHEAT)
                printk(KERN_INFO PFX "Card sensed a CPU Overheat\n");

        if (pcipcwd_private.boot_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 (pcipcwd_set_heartbeat(heartbeat)) {
                pcipcwd_set_heartbeat(WATCHDOG_HEARTBEAT);
                printk(KERN_INFO PFX "heartbeat value must be 0<heartbeat<65536, using %d\n",
                        WATCHDOG_HEARTBEAT);
        }

        ret = register_reboot_notifier(&pcipcwd_notifier);
        if (ret != 0) {
                printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
                        ret);
                goto err_out_release_region;
        }

        if (pcipcwd_private.supports_temp) {
                ret = misc_register(&pcipcwd_temp_miscdev);
                if (ret != 0) {
                        printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
                                TEMP_MINOR, ret);
                        goto err_out_unregister_reboot;
                }
        }

        ret = misc_register(&pcipcwd_miscdev);
        if (ret != 0) {
                printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
                        WATCHDOG_MINOR, ret);
                goto err_out_misc_deregister;
        }

        printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
                heartbeat, nowayout);

        return 0;

err_out_misc_deregister:
        if (pcipcwd_private.supports_temp)
                misc_deregister(&pcipcwd_temp_miscdev);
err_out_unregister_reboot:
        unregister_reboot_notifier(&pcipcwd_notifier);
err_out_release_region:
        pci_release_regions(pdev);
err_out_disable_device:
        pci_disable_device(pdev);
        return ret;
}

static void __devexit pcipcwd_card_exit(struct pci_dev *pdev)
{
        /* Stop the timer before we leave */
        if (!nowayout)
                pcipcwd_stop();

        /* Deregister */
        misc_deregister(&pcipcwd_miscdev);
        if (pcipcwd_private.supports_temp)
                misc_deregister(&pcipcwd_temp_miscdev);
        unregister_reboot_notifier(&pcipcwd_notifier);
        pci_release_regions(pdev);
        pci_disable_device(pdev);
        cards_found--;
}

static struct pci_device_id pcipcwd_pci_tbl[] = {
        { PCI_VENDOR_ID_QUICKLOGIC, PCI_DEVICE_ID_WATCHDOG_PCIPCWD,
                PCI_ANY_ID, PCI_ANY_ID, },
        { 0 },                  /* End of list */
};
MODULE_DEVICE_TABLE(pci, pcipcwd_pci_tbl);

static struct pci_driver pcipcwd_driver = {
        .name           = WATCHDOG_NAME,
        .id_table       = pcipcwd_pci_tbl,
        .probe          = pcipcwd_card_init,
        .remove         = __devexit_p(pcipcwd_card_exit),
};

static int __init pcipcwd_init_module(void)
{
        spin_lock_init (&pcipcwd_private.io_lock);

        return pci_register_driver(&pcipcwd_driver);
}

static void __exit pcipcwd_cleanup_module(void)
{
        pci_unregister_driver(&pcipcwd_driver);
}

module_init(pcipcwd_init_module);
module_exit(pcipcwd_cleanup_module);

MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
MODULE_DESCRIPTION("Berkshire PCI-PC Watchdog driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
MODULE_ALIAS_MISCDEV(TEMP_MINOR);