1 files changed, 463 insertions, 0 deletions

diff --git a/drivers/watchdog/sc1200wdt.c b/drivers/watchdog/sc1200wdt.c
new file mode 100644
index 000000000000..9670d47190d0
--- /dev/null
+++ b/drivers/watchdog/sc1200wdt.c
@@ -0,0 +1,463 @@
+/*
+ *      National Semiconductor PC87307/PC97307 (ala SC1200) WDT driver
+ *      (c) Copyright 2002 Zwane Mwaikambo <zwane@commfireservices.com>,
+ *                      All Rights Reserved.
+ *      Based on wdt.c and wdt977.c by Alan Cox and Woody Suwalski respectively.
+ *
+ *      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.
+ *
+ *      The author(s) of this software shall not be held liable for damages
+ *      of any nature resulting due to the use of this software. This
+ *      software is provided AS-IS with no warranties.
+ *
+ *      Changelog:
+ *      20020220 Zwane Mwaikambo        Code based on datasheet, no hardware.
+ *      20020221 Zwane Mwaikambo        Cleanups as suggested by Jeff Garzik and Alan Cox.
+ *      20020222 Zwane Mwaikambo        Added probing.
+ *      20020225 Zwane Mwaikambo        Added ISAPNP support.
+ *      20020412 Rob Radez              Broke out start/stop functions
+ *               <rob@osinvestor.com>   Return proper status instead of temperature warning
+ *                                      Add WDIOC_GETBOOTSTATUS and WDIOC_SETOPTIONS ioctls
+ *                                      Fix CONFIG_WATCHDOG_NOWAYOUT
+ *      20020530 Joel Becker            Add Matt Domsch's nowayout module option
+ *      20030116 Adam Belay             Updated to the latest pnp code
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/ioport.h>
+#include <linux/spinlock.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/init.h>
+#include <linux/pnp.h>
+#include <linux/fs.h>
+
+#include <asm/semaphore.h>
+#include <asm/io.h>
+#include <asm/uaccess.h>
+
+#define SC1200_MODULE_VER       "build 20020303"
+#define SC1200_MODULE_NAME      "sc1200wdt"
+#define PFX                     SC1200_MODULE_NAME ": "
+
+#define MAX_TIMEOUT     255     /* 255 minutes */
+#define PMIR            (io)    /* Power Management Index Register */
+#define PMDR            (io+1)  /* Power Management Data Register */
+
+/* Data Register indexes */
+#define FER1            0x00    /* Function enable register 1 */
+#define FER2            0x01    /* Function enable register 2 */
+#define PMC1            0x02    /* Power Management Ctrl 1 */
+#define PMC2            0x03    /* Power Management Ctrl 2 */
+#define PMC3            0x04    /* Power Management Ctrl 3 */
+#define WDTO            0x05    /* Watchdog timeout register */
+#define WDCF            0x06    /* Watchdog config register */
+#define WDST            0x07    /* Watchdog status register */
+
+/* WDCF bitfields - which devices assert WDO */
+#define KBC_IRQ         0x01    /* Keyboard Controller */
+#define MSE_IRQ         0x02    /* Mouse */
+#define UART1_IRQ       0x03    /* Serial0 */
+#define UART2_IRQ       0x04    /* Serial1 */
+/* 5 -7 are reserved */
+
+static char banner[] __initdata = KERN_INFO PFX SC1200_MODULE_VER;
+static int timeout = 1;
+static int io = -1;
+static int io_len = 2;          /* for non plug and play */
+static struct semaphore open_sem;
+static char expect_close;
+static spinlock_t sc1200wdt_lock;       /* io port access serialisation */
+
+#if defined CONFIG_PNP
+static int isapnp = 1;
+static struct pnp_dev *wdt_dev;
+
+module_param(isapnp, int, 0);
+MODULE_PARM_DESC(isapnp, "When set to 0 driver ISA PnP support will be disabled");
+#endif
+
+module_param(io, int, 0);
+MODULE_PARM_DESC(io, "io port");
+module_param(timeout, int, 0);
+MODULE_PARM_DESC(timeout, "range is 0-255 minutes, default is 1");
+
+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) ")");
+
+
+
+/* Read from Data Register */
+static inline void sc1200wdt_read_data(unsigned char index, unsigned char *data)
+{
+        spin_lock(&sc1200wdt_lock);
+        outb_p(index, PMIR);
+        *data = inb(PMDR);
+        spin_unlock(&sc1200wdt_lock);
+}
+
+
+/* Write to Data Register */
+static inline void sc1200wdt_write_data(unsigned char index, unsigned char data)
+{
+        spin_lock(&sc1200wdt_lock);
+        outb_p(index, PMIR);
+        outb(data, PMDR);
+        spin_unlock(&sc1200wdt_lock);
+}
+
+
+static void sc1200wdt_start(void)
+{
+        unsigned char reg;
+
+        sc1200wdt_read_data(WDCF, &reg);
+        /* assert WDO when any of the following interrupts are triggered too */
+        reg |= (KBC_IRQ | MSE_IRQ | UART1_IRQ | UART2_IRQ);
+        sc1200wdt_write_data(WDCF, reg);
+        /* set the timeout and get the ball rolling */
+        sc1200wdt_write_data(WDTO, timeout);
+}
+
+
+static void sc1200wdt_stop(void)
+{
+        sc1200wdt_write_data(WDTO, 0);
+}
+
+
+/* This returns the status of the WDO signal, inactive high. */
+static inline int sc1200wdt_status(void)
+{
+        unsigned char ret;
+
+        sc1200wdt_read_data(WDST, &ret);
+        /* If the bit is inactive, the watchdog is enabled, so return
+         * KEEPALIVEPING which is a bit of a kludge because there's nothing
+         * else for enabled/disabled status
+         */
+        return (ret & 0x01) ? 0 : WDIOF_KEEPALIVEPING;  /* bits 1 - 7 are undefined */
+}
+
+
+static int sc1200wdt_open(struct inode *inode, struct file *file)
+{
+        /* allow one at a time */
+        if (down_trylock(&open_sem))
+                return -EBUSY;
+
+        if (timeout > MAX_TIMEOUT)
+                timeout = MAX_TIMEOUT;
+
+        sc1200wdt_start();
+        printk(KERN_INFO PFX "Watchdog enabled, timeout = %d min(s)", timeout);
+
+        return nonseekable_open(inode, file);
+}
+
+
+static int sc1200wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
+{
+        int new_timeout;
+        void __user *argp = (void __user *)arg;
+        int __user *p = argp;
+        static struct watchdog_info ident = {
+                .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
+                .firmware_version = 0,
+                .identity = "PC87307/PC97307",
+        };
+
+        switch (cmd) {
+                default:
+                        return -ENOTTY;
+
+                case WDIOC_GETSUPPORT:
+                        if (copy_to_user(argp, &ident, sizeof ident))
+                                return -EFAULT;
+                        return 0;
+
+                case WDIOC_GETSTATUS:
+                        return put_user(sc1200wdt_status(), p);
+
+                case WDIOC_GETBOOTSTATUS:
+                        return put_user(0, p);
+
+                case WDIOC_KEEPALIVE:
+                        sc1200wdt_write_data(WDTO, timeout);
+                        return 0;
+
+                case WDIOC_SETTIMEOUT:
+                        if (get_user(new_timeout, p))
+                                return -EFAULT;
+
+                        /* the API states this is given in secs */
+                        new_timeout /= 60;
+                        if (new_timeout < 0 || new_timeout > MAX_TIMEOUT)
+                                return -EINVAL;
+
+                        timeout = new_timeout;
+                        sc1200wdt_write_data(WDTO, timeout);
+                        /* fall through and return the new timeout */
+
+                case WDIOC_GETTIMEOUT:
+                        return put_user(timeout * 60, p);
+
+                case WDIOC_SETOPTIONS:
+                {
+                        int options, retval = -EINVAL;
+
+                        if (get_user(options, p))
+                                return -EFAULT;
+
+                        if (options & WDIOS_DISABLECARD) {
+                                sc1200wdt_stop();
+                                retval = 0;
+                        }
+
+                        if (options & WDIOS_ENABLECARD) {
+                                sc1200wdt_start();
+                                retval = 0;
+                        }
+
+                        return retval;
+                }
+        }
+}
+
+
+static int sc1200wdt_release(struct inode *inode, struct file *file)
+{
+        if (expect_close == 42) {
+                sc1200wdt_stop();
+                printk(KERN_INFO PFX "Watchdog disabled\n");
+        } else {
+                sc1200wdt_write_data(WDTO, timeout);
+                printk(KERN_CRIT PFX "Unexpected close!, timeout = %d min(s)\n", timeout);
+        }
+        up(&open_sem);
+        expect_close = 0;
+
+        return 0;
+}
+
+
+static ssize_t sc1200wdt_write(struct file *file, const char __user *data, size_t len, loff_t *ppos)
+{
+        if (len) {
+                if (!nowayout) {
+                        size_t i;
+
+                        expect_close = 0;
+
+                        for (i = 0; i != len; i++) {
+                                char c;
+
+                                if (get_user(c, data+i))
+                                        return -EFAULT;
+                                if (c == 'V')
+                                        expect_close = 42;
+                        }
+                }
+
+                sc1200wdt_write_data(WDTO, timeout);
+                return len;
+        }
+
+        return 0;
+}
+
+
+static int sc1200wdt_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
+{
+        if (code == SYS_DOWN || code == SYS_HALT)
+                sc1200wdt_stop();
+
+        return NOTIFY_DONE;
+}
+
+
+static struct notifier_block sc1200wdt_notifier =
+{
+        .notifier_call =        sc1200wdt_notify_sys,
+};
+
+static const struct file_operations sc1200wdt_fops =
+{
+        .owner          = THIS_MODULE,
+        .llseek         = no_llseek,
+        .write          = sc1200wdt_write,
+        .ioctl          = sc1200wdt_ioctl,
+        .open           = sc1200wdt_open,
+        .release        = sc1200wdt_release,
+};
+
+static struct miscdevice sc1200wdt_miscdev =
+{
+        .minor          = WATCHDOG_MINOR,
+        .name           = "watchdog",
+        .fops           = &sc1200wdt_fops,
+};
+
+
+static int __init sc1200wdt_probe(void)
+{
+        /* The probe works by reading the PMC3 register's default value of 0x0e
+         * there is one caveat, if the device disables the parallel port or any
+         * of the UARTs we won't be able to detect it.
+         * Nb. This could be done with accuracy by reading the SID registers, but
+         * we don't have access to those io regions.
+         */
+
+        unsigned char reg;
+
+        sc1200wdt_read_data(PMC3, &reg);
+        reg &= 0x0f;                            /* we don't want the UART busy bits */
+        return (reg == 0x0e) ? 0 : -ENODEV;
+}
+
+
+#if defined CONFIG_PNP
+
+static struct pnp_device_id scl200wdt_pnp_devices[] = {
+        /* National Semiconductor PC87307/PC97307 watchdog component */
+        {.id = "NSC0800", .driver_data = 0},
+        {.id = ""},
+};
+
+static int scl200wdt_pnp_probe(struct pnp_dev * dev, const struct pnp_device_id *dev_id)
+{
+        /* this driver only supports one card at a time */
+        if (wdt_dev || !isapnp)
+                return -EBUSY;
+
+        wdt_dev = dev;
+        io = pnp_port_start(wdt_dev, 0);
+        io_len = pnp_port_len(wdt_dev, 0);
+
+        if (!request_region(io, io_len, SC1200_MODULE_NAME)) {
+                printk(KERN_ERR PFX "Unable to register IO port %#x\n", io);
+                return -EBUSY;
+        }
+
+        printk(KERN_INFO "scl200wdt: PnP device found at io port %#x/%d\n", io, io_len);
+        return 0;
+}
+
+static void scl200wdt_pnp_remove(struct pnp_dev * dev)
+{
+        if (wdt_dev){
+                release_region(io, io_len);
+                wdt_dev = NULL;
+        }
+}
+
+static struct pnp_driver scl200wdt_pnp_driver = {
+        .name           = "scl200wdt",
+        .id_table       = scl200wdt_pnp_devices,
+        .probe          = scl200wdt_pnp_probe,
+        .remove         = scl200wdt_pnp_remove,
+};
+
+#endif /* CONFIG_PNP */
+
+
+static int __init sc1200wdt_init(void)
+{
+        int ret;
+
+        printk("%s\n", banner);
+
+        spin_lock_init(&sc1200wdt_lock);
+        sema_init(&open_sem, 1);
+
+#if defined CONFIG_PNP
+        if (isapnp) {
+                ret = pnp_register_driver(&scl200wdt_pnp_driver);
+                if (ret)
+                        goto out_clean;
+        }
+#endif
+
+        if (io == -1) {
+                printk(KERN_ERR PFX "io parameter must be specified\n");
+                ret = -EINVAL;
+                goto out_pnp;
+        }
+
+#if defined CONFIG_PNP
+        /* now that the user has specified an IO port and we haven't detected
+         * any devices, disable pnp support */
+        isapnp = 0;
+        pnp_unregister_driver(&scl200wdt_pnp_driver);
+#endif
+
+        if (!request_region(io, io_len, SC1200_MODULE_NAME)) {
+                printk(KERN_ERR PFX "Unable to register IO port %#x\n", io);
+                ret = -EBUSY;
+                goto out_pnp;
+        }
+
+        ret = sc1200wdt_probe();
+        if (ret)
+                goto out_io;
+
+        ret = register_reboot_notifier(&sc1200wdt_notifier);
+        if (ret) {
+                printk(KERN_ERR PFX "Unable to register reboot notifier err = %d\n", ret);
+                goto out_io;
+        }
+
+        ret = misc_register(&sc1200wdt_miscdev);
+        if (ret) {
+                printk(KERN_ERR PFX "Unable to register miscdev on minor %d\n", WATCHDOG_MINOR);
+                goto out_rbt;
+        }
+
+        /* ret = 0 */
+
+out_clean:
+        return ret;
+
+out_rbt:
+        unregister_reboot_notifier(&sc1200wdt_notifier);
+
+out_io:
+        release_region(io, io_len);
+
+out_pnp:
+#if defined CONFIG_PNP
+        if (isapnp)
+                pnp_unregister_driver(&scl200wdt_pnp_driver);
+#endif
+        goto out_clean;
+}
+
+
+static void __exit sc1200wdt_exit(void)
+{
+        misc_deregister(&sc1200wdt_miscdev);
+        unregister_reboot_notifier(&sc1200wdt_notifier);
+
+#if defined CONFIG_PNP
+        if(isapnp)
+                pnp_unregister_driver(&scl200wdt_pnp_driver);
+        else
+#endif
+        release_region(io, io_len);
+}
+
+module_init(sc1200wdt_init);
+module_exit(sc1200wdt_exit);
+
+MODULE_AUTHOR("Zwane Mwaikambo <zwane@commfireservices.com>");
+MODULE_DESCRIPTION("Driver for National Semiconductor PC87307/PC97307 watchdog component");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);