1 files changed, 459 insertions, 0 deletions
diff --git a/drivers/char/watchdog/wdt977.c b/drivers/char/watchdog/wdt977.c
new file mode 100644
index 000000000000..072e9b214759
--- /dev/null
+++ b/drivers/char/watchdog/wdt977.c
@@ -0,0 +1,459 @@
+/*
+ *	Wdt977	0.03:	A Watchdog Device for Netwinder W83977AF chip
+ *
+ *	(c) Copyright 1998 Rebel.com (Woody Suwalski <woody@netwinder.org>)
+ *
+ *			-----------------------
+ *
+ *	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.
+ *
+ *			-----------------------
+ *      14-Dec-2001 Matt Domsch <Matt_Domsch@dell.com>
+ *           Added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT
+ *	19-Dec-2001 Woody Suwalski: Netwinder fixes, ioctl interface
+ *	06-Jan-2002 Woody Suwalski: For compatibility, convert all timeouts
+ *				    from minutes to seconds.
+ *      07-Jul-2003 Daniele Bellucci: Audit return code of misc_register in
+ *                                    nwwatchdog_init.
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/init.h>
+#include <linux/watchdog.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+
+#include <asm/io.h>
+#include <asm/system.h>
+#include <asm/mach-types.h>
+#include <asm/uaccess.h>
+
+#define PFX "Wdt977: "
+#define WATCHDOG_MINOR	130
+
+#define	DEFAULT_TIMEOUT	60			/* default timeout in seconds */
+
+static	int timeout = DEFAULT_TIMEOUT;
+static	int timeoutM;				/* timeout in minutes */
+static	unsigned long timer_alive;
+static	int testmode;
+static	char expect_close;
+
+module_param(timeout, int, 0);
+MODULE_PARM_DESC(timeout,"Watchdog timeout in seconds (60..15300), default=" __MODULE_STRING(DEFAULT_TIMEOUT) ")");
+module_param(testmode, int, 0);
+MODULE_PARM_DESC(testmode,"Watchdog testmode (1 = no reboot), default=0");
+
+#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)");
+
+/*
+ * Start the watchdog
+ */
+
+static int wdt977_start(void)
+{
+	/* unlock the SuperIO chip */
+	outb(0x87,0x370);
+	outb(0x87,0x370);
+
+	/* select device Aux2 (device=8) and set watchdog regs F2, F3 and F4
+	 * F2 has the timeout in minutes
+	 * F3 could be set to the POWER LED blink (with GP17 set to PowerLed)
+	 *   at timeout, and to reset timer on kbd/mouse activity (not impl.)
+	 * F4 is used to just clear the TIMEOUT'ed state (bit 0)
+	 */
+	outb(0x07,0x370);
+	outb(0x08,0x371);
+	outb(0xF2,0x370);
+	outb(timeoutM,0x371);
+	outb(0xF3,0x370);
+	outb(0x00,0x371);	/* another setting is 0E for kbd/mouse/LED */
+	outb(0xF4,0x370);
+	outb(0x00,0x371);
+
+	/* at last select device Aux1 (dev=7) and set GP16 as a watchdog output */
+	/* in test mode watch the bit 1 on F4 to indicate "triggered" */
+	if (!testmode)
+	{
+		outb(0x07,0x370);
+		outb(0x07,0x371);
+		outb(0xE6,0x370);
+		outb(0x08,0x371);
+	}
+
+	/* lock the SuperIO chip */
+	outb(0xAA,0x370);
+
+	printk(KERN_INFO PFX "activated.\n");
+
+	return 0;
+}
+
+/*
+ * Stop the watchdog
+ */
+
+static int wdt977_stop(void)
+{
+	/* unlock the SuperIO chip */
+	outb(0x87,0x370);
+	outb(0x87,0x370);
+
+	/* select device Aux2 (device=8) and set watchdog regs F2,F3 and F4
+	* F3 is reset to its default state
+	* F4 can clear the TIMEOUT'ed state (bit 0) - back to default
+	* We can not use GP17 as a PowerLed, as we use its usage as a RedLed
+	*/
+	outb(0x07,0x370);
+	outb(0x08,0x371);
+	outb(0xF2,0x370);
+	outb(0xFF,0x371);
+	outb(0xF3,0x370);
+	outb(0x00,0x371);
+	outb(0xF4,0x370);
+	outb(0x00,0x371);
+	outb(0xF2,0x370);
+	outb(0x00,0x371);
+
+	/* at last select device Aux1 (dev=7) and set GP16 as a watchdog output */
+	outb(0x07,0x370);
+	outb(0x07,0x371);
+	outb(0xE6,0x370);
+	outb(0x08,0x371);
+
+	/* lock the SuperIO chip */
+	outb(0xAA,0x370);
+
+	printk(KERN_INFO PFX "shutdown.\n");
+
+	return 0;
+}
+
+/*
+ * Send a keepalive ping to the watchdog
+ * This is done by simply re-writing the timeout to reg. 0xF2
+ */
+
+static int wdt977_keepalive(void)
+{
+	/* unlock the SuperIO chip */
+	outb(0x87,0x370);
+	outb(0x87,0x370);
+
+	/* select device Aux2 (device=8) and kicks watchdog reg F2 */
+	/* F2 has the timeout in minutes */
+	outb(0x07,0x370);
+	outb(0x08,0x371);
+	outb(0xF2,0x370);
+	outb(timeoutM,0x371);
+
+	/* lock the SuperIO chip */
+	outb(0xAA,0x370);
+
+	return 0;
+}
+
+/*
+ * Set the watchdog timeout value
+ */
+
+static int wdt977_set_timeout(int t)
+{
+	int tmrval;
+
+	/* convert seconds to minutes, rounding up */
+	tmrval = (t + 59) / 60;
+
+	if (machine_is_netwinder()) {
+		/* we have a hw bug somewhere, so each 977 minute is actually only 30sec
+		 *  this limits the max timeout to half of device max of 255 minutes...
+		 */
+		tmrval += tmrval;
+	}
+
+	if ((tmrval < 1) || (tmrval > 255))
+		return -EINVAL;
+
+	/* timeout is the timeout in seconds, timeoutM is the timeout in minutes) */
+	timeout = t;
+	timeoutM = tmrval;
+	return 0;
+}
+
+/*
+ * Get the watchdog status
+ */
+
+static int wdt977_get_status(int *status)
+{
+	int new_status;
+
+	*status=0;
+
+	/* unlock the SuperIO chip */
+	outb(0x87,0x370);
+	outb(0x87,0x370);
+
+	/* select device Aux2 (device=8) and read watchdog reg F4 */
+	outb(0x07,0x370);
+	outb(0x08,0x371);
+	outb(0xF4,0x370);
+	new_status = inb(0x371);
+
+	/* lock the SuperIO chip */
+	outb(0xAA,0x370);
+
+	if (new_status & 1)
+		*status |= WDIOF_CARDRESET;
+
+	return 0;
+}
+
+
+/*
+ *	/dev/watchdog handling
+ */
+
+static int wdt977_open(struct inode *inode, struct file *file)
+{
+	/* If the watchdog is alive we don't need to start it again */
+	if( test_and_set_bit(0,&timer_alive) )
+		return -EBUSY;
+
+	if (nowayout)
+		__module_get(THIS_MODULE);
+
+	wdt977_start();
+	return nonseekable_open(inode, file);
+}
+
+static int wdt977_release(struct inode *inode, struct file *file)
+{
+	/*
+	 *	Shut off the timer.
+	 * 	Lock it in if it's a module and we set nowayout
+	 */
+	if (expect_close == 42)
+	{
+		wdt977_stop();
+		clear_bit(0,&timer_alive);
+	} else {
+		printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
+		wdt977_keepalive();
+	}
+	expect_close = 0;
+	return 0;
+}
+
+
+/*
+ *      wdt977_write:
+ *      @file: file handle to the watchdog
+ *      @buf: buffer to write (unused as data does not matter here
+ *      @count: count of bytes
+ *      @ppos: pointer to the position to write. No seeks allowed
+ *
+ *      A write to a watchdog device is defined as a keepalive signal. Any
+ *      write of data will do, as we we don't define content meaning.
+ */
+
+static ssize_t wdt977_write(struct file *file, const char __user *buf,
+			    size_t count, loff_t *ppos)
+{
+	if (count) {
+		if (!nowayout) {
+			size_t i;
+
+			/* In case it was set long ago */
+			expect_close = 0;
+
+			for (i = 0; i != count; i++) {
+				char c;
+				if (get_user(c, buf + i))
+					return -EFAULT;
+				if (c == 'V')
+					expect_close = 42;
+			}
+		}
+
+		wdt977_keepalive();
+	}
+	return count;
+}
+
+/*
+ *      wdt977_ioctl:
+ *      @inode: inode of the device
+ *      @file: file handle to the device
+ *      @cmd: watchdog command
+ *      @arg: argument pointer
+ *
+ *      The watchdog API defines a common set of functions for all watchdogs
+ *      according to their available features.
+ */
+
+static struct watchdog_info ident = {
+	.options =		WDIOF_SETTIMEOUT |
+				WDIOF_MAGICCLOSE |
+				WDIOF_KEEPALIVEPING,
+	.firmware_version =	1,
+	.identity =		"Winbond 83977",
+};
+
+static int wdt977_ioctl(struct inode *inode, struct file *file,
+	unsigned int cmd, unsigned long arg)
+{
+	int status;
+	int new_options, retval = -EINVAL;
+	int new_timeout;
+	union {
+		struct watchdog_info __user *ident;
+		int __user *i;
+	} uarg;
+
+	uarg.i = (int __user *)arg;
+
+	switch(cmd)
+	{
+	default:
+		return -ENOIOCTLCMD;
+
+	case WDIOC_GETSUPPORT:
+		return copy_to_user(uarg.ident, &ident,
+			sizeof(ident)) ? -EFAULT : 0;
+
+	case WDIOC_GETSTATUS:
+		wdt977_get_status(&status);
+		return put_user(status, uarg.i);
+
+	case WDIOC_GETBOOTSTATUS:
+		return put_user(0, uarg.i);
+
+	case WDIOC_KEEPALIVE:
+		wdt977_keepalive();
+		return 0;
+
+	case WDIOC_SETOPTIONS:
+		if (get_user (new_options, uarg.i))
+			return -EFAULT;
+
+		if (new_options & WDIOS_DISABLECARD) {
+			wdt977_stop();
+			retval = 0;
+		}
+
+		if (new_options & WDIOS_ENABLECARD) {
+			wdt977_start();
+			retval = 0;
+		}
+
+		return retval;
+
+	case WDIOC_SETTIMEOUT:
+		if (get_user(new_timeout, uarg.i))
+			return -EFAULT;
+
+		if (wdt977_set_timeout(new_timeout))
+		    return -EINVAL;
+
+		wdt977_keepalive();
+		/* Fall */
+
+	case WDIOC_GETTIMEOUT:
+		return put_user(timeout, uarg.i);
+
+	}
+}
+
+static int wdt977_notify_sys(struct notifier_block *this, unsigned long code,
+	void *unused)
+{
+	if(code==SYS_DOWN || code==SYS_HALT)
+		wdt977_stop();
+	return NOTIFY_DONE;
+}
+
+static struct file_operations wdt977_fops=
+{
+	.owner		= THIS_MODULE,
+	.llseek		= no_llseek,
+	.write		= wdt977_write,
+	.ioctl		= wdt977_ioctl,
+	.open		= wdt977_open,
+	.release	= wdt977_release,
+};
+
+static struct miscdevice wdt977_miscdev=
+{
+	.minor		= WATCHDOG_MINOR,
+	.name		= "watchdog",
+	.fops		= &wdt977_fops,
+};
+
+static struct notifier_block wdt977_notifier = {
+	.notifier_call = wdt977_notify_sys,
+};
+
+static int __init nwwatchdog_init(void)
+{
+	int retval;
+	if (!machine_is_netwinder())
+		return -ENODEV;
+
+	/* Check that the timeout value is within it's range ; if not reset to the default */
+	if (wdt977_set_timeout(timeout)) {
+		wdt977_set_timeout(DEFAULT_TIMEOUT);
+		printk(KERN_INFO PFX "timeout value must be 60<timeout<15300, using %d\n",
+			DEFAULT_TIMEOUT);
+	}
+
+	retval = register_reboot_notifier(&wdt977_notifier);
+	if (retval) {
+		printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
+			retval);
+		return retval;
+	}
+
+	retval = misc_register(&wdt977_miscdev);
+	if (retval) {
+		printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
+			WATCHDOG_MINOR, retval);
+		unregister_reboot_notifier(&wdt977_notifier);
+		return retval;
+	}
+
+	printk(KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d, testmode = %i)\n",
+		timeout, nowayout, testmode);
+
+	return 0;
+}
+
+static void __exit nwwatchdog_exit(void)
+{
+	misc_deregister(&wdt977_miscdev);
+	unregister_reboot_notifier(&wdt977_notifier);
+}
+
+module_init(nwwatchdog_init);
+module_exit(nwwatchdog_exit);
+
+MODULE_AUTHOR("Woody Suwalski <woody@netwinder.org>");
+MODULE_DESCRIPTION("W83977AF Watchdog driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);