1 files changed, 348 insertions, 0 deletions

diff --git a/drivers/watchdog/acquirewdt.c b/drivers/watchdog/acquirewdt.c
new file mode 100644
index 000000000000..85269c365a10
--- /dev/null
+++ b/drivers/watchdog/acquirewdt.c
@@ -0,0 +1,348 @@
+/*
+ *      Acquire Single Board Computer Watchdog Timer driver
+ *
+ *      Based on wdt.c. Original copyright messages:
+ *
+ *      (c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved.
+ *                              http://www.redhat.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 Alan Cox nor CymruNet Ltd. admit liability nor provide
+ *      warranty for any of this software. This material is provided
+ *      "AS-IS" and at no charge.
+ *
+ *      (c) Copyright 1995    Alan Cox <alan@redhat.com>
+ *
+ *      14-Dec-2001 Matt Domsch <Matt_Domsch@dell.com>
+ *          Added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT
+ *          Can't add timeout - driver doesn't allow changing value
+ */
+
+/*
+ *      Theory of Operation:
+ *              The Watch-Dog Timer is provided to ensure that standalone
+ *              Systems can always recover from catastrophic conditions that
+ *              caused the CPU to crash. This condition may have occured by
+ *              external EMI or a software bug. When the CPU stops working
+ *              correctly, hardware on the board will either perform a hardware
+ *              reset (cold boot) or a non-maskable interrupt (NMI) to bring the
+ *              system back to a known state.
+ *
+ *              The Watch-Dog Timer is controlled by two I/O Ports.
+ *                443 hex       - Read  - Enable or refresh the Watch-Dog Timer
+ *                043 hex       - Read  - Disable the Watch-Dog Timer
+ *
+ *              To enable the Watch-Dog Timer, a read from I/O port 443h must
+ *              be performed. This will enable and activate the countdown timer
+ *              which will eventually time out and either reset the CPU or cause
+ *              an NMI depending on the setting of a jumper. To ensure that this
+ *              reset condition does not occur, the Watch-Dog Timer must be
+ *              periodically refreshed by reading the same I/O port 443h.
+ *              The Watch-Dog Timer is disabled by reading I/O port 043h.
+ *
+ *              The Watch-Dog Timer Time-Out Period is set via jumpers.
+ *              It can be 1, 2, 10, 20, 110 or 220 seconds.
+ */
+
+/*
+ *      Includes, defines, variables, module parameters, ...
+ */
+
+/* Includes */
+#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/miscdevice.h>           /* For MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR) */
+#include <linux/watchdog.h>             /* For the watchdog specific items */
+#include <linux/fs.h>                   /* For file operations */
+#include <linux/ioport.h>               /* For io-port access */
+#include <linux/platform_device.h>      /* For platform_driver framework */
+#include <linux/init.h>                 /* For __init/__exit/... */
+
+#include <asm/uaccess.h>                /* For copy_to_user/put_user/... */
+#include <asm/io.h>                     /* For inb/outb/... */
+
+/* Module information */
+#define DRV_NAME "acquirewdt"
+#define PFX DRV_NAME ": "
+#define WATCHDOG_NAME "Acquire WDT"
+#define WATCHDOG_HEARTBEAT 0    /* There is no way to see what the correct time-out period is */
+
+/* internal variables */
+static struct platform_device *acq_platform_device;     /* the watchdog platform device */
+static unsigned long acq_is_open;
+static char expect_close;
+
+/* module parameters */
+static int wdt_stop = 0x43;     /* You must set this - there is no sane way to probe for this board. */
+module_param(wdt_stop, int, 0);
+MODULE_PARM_DESC(wdt_stop, "Acquire WDT 'stop' io port (default 0x43)");
+
+static int wdt_start = 0x443;   /* You must set this - there is no sane way to probe for this board. */
+module_param(wdt_start, int, 0);
+MODULE_PARM_DESC(wdt_start, "Acquire WDT 'start' io port (default 0x443)");
+
+static int nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, int, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+/*
+ *      Watchdog Operations
+ */
+
+static void acq_keepalive(void)
+{
+        /* Write a watchdog value */
+        inb_p(wdt_start);
+}
+
+static void acq_stop(void)
+{
+        /* Turn the card off */
+        inb_p(wdt_stop);
+}
+
+/*
+ *      /dev/watchdog handling
+ */
+
+static ssize_t acq_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
+{
+        /* See if we got the magic character 'V' and reload the timer */
+        if(count) {
+                if (!nowayout) {
+                        size_t i;
+
+                        /* note: just in case someone wrote the magic character
+                         * five months ago... */
+                        expect_close = 0;
+
+                        /* scan to see whether or not we got the magic character */
+                        for (i = 0; i != count; i++) {
+                                char c;
+                                if (get_user(c, buf + i))
+                                        return -EFAULT;
+                                if (c == 'V')
+                                        expect_close = 42;
+                        }
+                }
+
+                /* Well, anyhow someone wrote to us, we should return that favour */
+                acq_keepalive();
+        }
+        return count;
+}
+
+static int acq_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
+        unsigned long arg)
+{
+        int options, retval = -EINVAL;
+        void __user *argp = (void __user *)arg;
+        int __user *p = argp;
+        static struct watchdog_info ident =
+        {
+                .options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+                .firmware_version = 1,
+                .identity = WATCHDOG_NAME,
+        };
+
+        switch(cmd)
+        {
+        case WDIOC_GETSUPPORT:
+          return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
+
+        case WDIOC_GETSTATUS:
+        case WDIOC_GETBOOTSTATUS:
+          return put_user(0, p);
+
+        case WDIOC_KEEPALIVE:
+          acq_keepalive();
+          return 0;
+
+        case WDIOC_GETTIMEOUT:
+          return put_user(WATCHDOG_HEARTBEAT, p);
+
+        case WDIOC_SETOPTIONS:
+        {
+            if (get_user(options, p))
+              return -EFAULT;
+
+            if (options & WDIOS_DISABLECARD)
+            {
+              acq_stop();
+              retval = 0;
+            }
+
+            if (options & WDIOS_ENABLECARD)
+            {
+              acq_keepalive();
+              retval = 0;
+            }
+
+            return retval;
+        }
+
+        default:
+          return -ENOTTY;
+        }
+}
+
+static int acq_open(struct inode *inode, struct file *file)
+{
+        if (test_and_set_bit(0, &acq_is_open))
+                return -EBUSY;
+
+        if (nowayout)
+                __module_get(THIS_MODULE);
+
+        /* Activate */
+        acq_keepalive();
+        return nonseekable_open(inode, file);
+}
+
+static int acq_close(struct inode *inode, struct file *file)
+{
+        if (expect_close == 42) {
+                acq_stop();
+        } else {
+                printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
+                acq_keepalive();
+        }
+        clear_bit(0, &acq_is_open);
+        expect_close = 0;
+        return 0;
+}
+
+/*
+ *      Kernel Interfaces
+ */
+
+static const struct file_operations acq_fops = {
+        .owner          = THIS_MODULE,
+        .llseek         = no_llseek,
+        .write          = acq_write,
+        .ioctl          = acq_ioctl,
+        .open           = acq_open,
+        .release        = acq_close,
+};
+
+static struct miscdevice acq_miscdev = {
+        .minor  = WATCHDOG_MINOR,
+        .name   = "watchdog",
+        .fops   = &acq_fops,
+};
+
+/*
+ *      Init & exit routines
+ */
+
+static int __devinit acq_probe(struct platform_device *dev)
+{
+        int ret;
+
+        if (wdt_stop != wdt_start) {
+                if (!request_region(wdt_stop, 1, WATCHDOG_NAME)) {
+                        printk (KERN_ERR PFX "I/O address 0x%04x already in use\n",
+                                wdt_stop);
+                        ret = -EIO;
+                        goto out;
+                }
+        }
+
+        if (!request_region(wdt_start, 1, WATCHDOG_NAME)) {
+                printk (KERN_ERR PFX "I/O address 0x%04x already in use\n",
+                        wdt_start);
+                ret = -EIO;
+                goto unreg_stop;
+        }
+
+        ret = misc_register(&acq_miscdev);
+        if (ret != 0) {
+                printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
+                        WATCHDOG_MINOR, ret);
+                goto unreg_regions;
+        }
+
+        printk (KERN_INFO PFX "initialized. (nowayout=%d)\n",
+                nowayout);
+
+        return 0;
+
+unreg_regions:
+        release_region(wdt_start, 1);
+unreg_stop:
+        if (wdt_stop != wdt_start)
+                release_region(wdt_stop, 1);
+out:
+        return ret;
+}
+
+static int __devexit acq_remove(struct platform_device *dev)
+{
+        misc_deregister(&acq_miscdev);
+        release_region(wdt_start,1);
+        if(wdt_stop != wdt_start)
+                release_region(wdt_stop,1);
+
+        return 0;
+}
+
+static void acq_shutdown(struct platform_device *dev)
+{
+        /* Turn the WDT off if we have a soft shutdown */
+        acq_stop();
+}
+
+static struct platform_driver acquirewdt_driver = {
+        .probe          = acq_probe,
+        .remove         = __devexit_p(acq_remove),
+        .shutdown       = acq_shutdown,
+        .driver         = {
+                .owner  = THIS_MODULE,
+                .name   = DRV_NAME,
+        },
+};
+
+static int __init acq_init(void)
+{
+        int err;
+
+        printk(KERN_INFO "WDT driver for Acquire single board computer initialising.\n");
+
+        err = platform_driver_register(&acquirewdt_driver);
+        if (err)
+                return err;
+
+        acq_platform_device = platform_device_register_simple(DRV_NAME, -1, NULL, 0);
+        if (IS_ERR(acq_platform_device)) {
+                err = PTR_ERR(acq_platform_device);
+                goto unreg_platform_driver;
+        }
+
+        return 0;
+
+unreg_platform_driver:
+        platform_driver_unregister(&acquirewdt_driver);
+        return err;
+}
+
+static void __exit acq_exit(void)
+{
+        platform_device_unregister(acq_platform_device);
+        platform_driver_unregister(&acquirewdt_driver);
+        printk(KERN_INFO PFX "Watchdog Module Unloaded.\n");
+}
+
+module_init(acq_init);
+module_exit(acq_exit);
+
+MODULE_AUTHOR("David Woodhouse");
+MODULE_DESCRIPTION("Acquire Inc. Single Board Computer Watchdog Timer driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);