Initial import

1 files changed, 231 insertions, 0 deletions

diff --git a/drivers/watchdog/wdt285.c b/drivers/watchdog/wdt285.c
new file mode 100644
index 000000000..ebbb183be
--- /dev/null
+++ b/drivers/watchdog/wdt285.c
@@ -0,0 +1,231 @@
+/*
+ *	Intel 21285 watchdog driver
+ *	Copyright (c) Phil Blundell <pb@nexus.co.uk>, 1998
+ *
+ *	based on
+ *
+ *	SoftDog	0.05:	A Software Watchdog Device
+ *
+ *	(c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>,
+ *						All Rights Reserved.
+ *
+ *	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.
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/reboot.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/uaccess.h>
+#include <linux/irq.h>
+#include <mach/hardware.h>
+
+#include <asm/mach-types.h>
+#include <asm/system_info.h>
+#include <asm/hardware/dec21285.h>
+
+/*
+ * Define this to stop the watchdog actually rebooting the machine.
+ */
+#undef ONLY_TESTING
+
+static unsigned int soft_margin = 60;		/* in seconds */
+static unsigned int reload;
+static unsigned long timer_alive;
+
+#ifdef ONLY_TESTING
+/*
+ *	If the timer expires..
+ */
+static void watchdog_fire(int irq, void *dev_id)
+{
+	pr_crit("Would Reboot\n");
+	*CSR_TIMER4_CNTL = 0;
+	*CSR_TIMER4_CLR = 0;
+}
+#endif
+
+/*
+ *	Refresh the timer.
+ */
+static void watchdog_ping(void)
+{
+	*CSR_TIMER4_LOAD = reload;
+}
+
+/*
+ *	Allow only one person to hold it open
+ */
+static int watchdog_open(struct inode *inode, struct file *file)
+{
+	int ret;
+
+	if (*CSR_SA110_CNTL & (1 << 13))
+		return -EBUSY;
+
+	if (test_and_set_bit(1, &timer_alive))
+		return -EBUSY;
+
+	reload = soft_margin * (mem_fclk_21285 / 256);
+
+	*CSR_TIMER4_CLR = 0;
+	watchdog_ping();
+	*CSR_TIMER4_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_AUTORELOAD
+		| TIMER_CNTL_DIV256;
+
+#ifdef ONLY_TESTING
+	ret = request_irq(IRQ_TIMER4, watchdog_fire, 0, "watchdog", NULL);
+	if (ret) {
+		*CSR_TIMER4_CNTL = 0;
+		clear_bit(1, &timer_alive);
+	}
+#else
+	/*
+	 * Setting this bit is irreversible; once enabled, there is
+	 * no way to disable the watchdog.
+	 */
+	*CSR_SA110_CNTL |= 1 << 13;
+
+	ret = 0;
+#endif
+	nonseekable_open(inode, file);
+	return ret;
+}
+
+/*
+ *	Shut off the timer.
+ *	Note: if we really have enabled the watchdog, there
+ *	is no way to turn off.
+ */
+static int watchdog_release(struct inode *inode, struct file *file)
+{
+#ifdef ONLY_TESTING
+	free_irq(IRQ_TIMER4, NULL);
+	clear_bit(1, &timer_alive);
+#endif
+	return 0;
+}
+
+static ssize_t watchdog_write(struct file *file, const char __user *data,
+			      size_t len, loff_t *ppos)
+{
+	/*
+	 *	Refresh the timer.
+	 */
+	if (len)
+		watchdog_ping();
+
+	return len;
+}
+
+static const struct watchdog_info ident = {
+	.options	= WDIOF_SETTIMEOUT,
+	.identity	= "Footbridge Watchdog",
+};
+
+static long watchdog_ioctl(struct file *file, unsigned int cmd,
+			   unsigned long arg)
+{
+	int __user *int_arg = (int __user *)arg;
+	int new_margin, ret = -ENOTTY;
+
+	switch (cmd) {
+	case WDIOC_GETSUPPORT:
+		ret = 0;
+		if (copy_to_user((void __user *)arg, &ident, sizeof(ident)))
+			ret = -EFAULT;
+		break;
+
+	case WDIOC_GETSTATUS:
+	case WDIOC_GETBOOTSTATUS:
+		ret = put_user(0, int_arg);
+		break;
+
+	case WDIOC_KEEPALIVE:
+		watchdog_ping();
+		ret = 0;
+		break;
+
+	case WDIOC_SETTIMEOUT:
+		ret = get_user(new_margin, int_arg);
+		if (ret)
+			break;
+
+		/* Arbitrary, can't find the card's limits */
+		if (new_margin < 0 || new_margin > 60) {
+			ret = -EINVAL;
+			break;
+		}
+
+		soft_margin = new_margin;
+		reload = soft_margin * (mem_fclk_21285 / 256);
+		watchdog_ping();
+		/* Fall */
+	case WDIOC_GETTIMEOUT:
+		ret = put_user(soft_margin, int_arg);
+		break;
+	}
+	return ret;
+}
+
+static const struct file_operations watchdog_fops = {
+	.owner		= THIS_MODULE,
+	.llseek		= no_llseek,
+	.write		= watchdog_write,
+	.unlocked_ioctl	= watchdog_ioctl,
+	.open		= watchdog_open,
+	.release	= watchdog_release,
+};
+
+static struct miscdevice watchdog_miscdev = {
+	.minor		= WATCHDOG_MINOR,
+	.name		= "watchdog",
+	.fops		= &watchdog_fops,
+};
+
+static int __init footbridge_watchdog_init(void)
+{
+	int retval;
+
+	if (machine_is_netwinder())
+		return -ENODEV;
+
+	retval = misc_register(&watchdog_miscdev);
+	if (retval < 0)
+		return retval;
+
+	pr_info("Footbridge Watchdog Timer: 0.01, timer margin: %d sec\n",
+		soft_margin);
+
+	if (machine_is_cats())
+		pr_warn("Warning: Watchdog reset may not work on this machine\n");
+	return 0;
+}
+
+static void __exit footbridge_watchdog_exit(void)
+{
+	misc_deregister(&watchdog_miscdev);
+}
+
+MODULE_AUTHOR("Phil Blundell <pb@nexus.co.uk>");
+MODULE_DESCRIPTION("Footbridge watchdog driver");
+MODULE_LICENSE("GPL");
+
+module_param(soft_margin, int, 0);
+MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds");
+
+module_init(footbridge_watchdog_init);
+module_exit(footbridge_watchdog_exit);