1 files changed, 216 insertions, 0 deletions
diff --git a/drivers/char/watchdog/sbc_epx_c3.c b/drivers/char/watchdog/sbc_epx_c3.c
new file mode 100644
index 000000000000..951764614ebf
--- /dev/null
+++ b/drivers/char/watchdog/sbc_epx_c3.c
@@ -0,0 +1,216 @@
+/*
+ *	SBC EPX C3 0.1	A Hardware Watchdog Device for the Winsystems EPX-C3
+ *	single board computer
+ *
+ *	(c) Copyright 2006 Calin A. Culianu <calin@ajvar.org>, 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.
+ *
+ *	based on softdog.c by Alan Cox <alan@redhat.com>
+ */
+
+#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/mm.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/init.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+
+#define PFX "epx_c3: "
+static int epx_c3_alive;
+
+#define WATCHDOG_TIMEOUT 1		/* 1 sec default timeout */
+
+static int nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, int, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
+
+#define EPXC3_WATCHDOG_CTL_REG 0x1ee /* write 1 to enable, 0 to disable */
+#define EPXC3_WATCHDOG_PET_REG 0x1ef /* write anything to pet once enabled */
+
+static void epx_c3_start(void)
+{
+	outb(1, EPXC3_WATCHDOG_CTL_REG);
+}
+
+static void epx_c3_stop(void)
+{
+
+	outb(0, EPXC3_WATCHDOG_CTL_REG);
+
+	printk(KERN_INFO PFX "Stopped watchdog timer.\n");
+}
+
+static void epx_c3_pet(void)
+{
+	outb(1, EPXC3_WATCHDOG_PET_REG);
+}
+
+/*
+ *	Allow only one person to hold it open
+ */
+static int epx_c3_open(struct inode *inode, struct file *file)
+{
+	if (epx_c3_alive)
+		return -EBUSY;
+
+	if (nowayout)
+		__module_get(THIS_MODULE);
+
+	/* Activate timer */
+	epx_c3_start();
+	epx_c3_pet();
+
+	epx_c3_alive = 1;
+	printk(KERN_INFO "Started watchdog timer.\n");
+
+	return nonseekable_open(inode, file);
+}
+
+static int epx_c3_release(struct inode *inode, struct file *file)
+{
+	/* Shut off the timer.
+	 * Lock it in if it's a module and we defined ...NOWAYOUT */
+	if (!nowayout)
+		epx_c3_stop();		/* Turn the WDT off */
+
+	epx_c3_alive = 0;
+
+	return 0;
+}
+
+static ssize_t epx_c3_write(struct file *file, const char *data,
+			size_t len, loff_t *ppos)
+{
+	/* Refresh the timer. */
+	if (len)
+		epx_c3_pet();
+	return len;
+}
+
+static int epx_c3_ioctl(struct inode *inode, struct file *file,
+			unsigned int cmd, unsigned long arg)
+{
+	int options, retval = -EINVAL;
+	static struct watchdog_info ident = {
+		.options		= WDIOF_KEEPALIVEPING |
+					  WDIOF_MAGICCLOSE,
+		.firmware_version	= 0,
+		.identity		= "Winsystems EPX-C3 H/W Watchdog",
+	};
+
+	switch (cmd) {
+	case WDIOC_GETSUPPORT:
+		if (copy_to_user((struct watchdog_info *)arg,
+				 &ident, sizeof(ident)))
+			return -EFAULT;
+		return 0;
+	case WDIOC_GETSTATUS:
+	case WDIOC_GETBOOTSTATUS:
+		return put_user(0,(int *)arg);
+	case WDIOC_KEEPALIVE:
+		epx_c3_pet();
+		return 0;
+	case WDIOC_GETTIMEOUT:
+		return put_user(WATCHDOG_TIMEOUT,(int *)arg);
+	case WDIOC_SETOPTIONS: {
+		if (get_user(options, (int *)arg))
+			return -EFAULT;
+
+		if (options & WDIOS_DISABLECARD) {
+			epx_c3_stop();
+			retval = 0;
+		}
+
+		if (options & WDIOS_ENABLECARD) {
+			epx_c3_start();
+			retval = 0;
+		}
+
+		return retval;
+	}
+	default:
+		return -ENOIOCTLCMD;
+	}
+}
+
+static int epx_c3_notify_sys(struct notifier_block *this, unsigned long code,
+				void *unused)
+{
+	if (code == SYS_DOWN || code == SYS_HALT)
+		epx_c3_stop();		/* Turn the WDT off */
+
+	return NOTIFY_DONE;
+}
+
+static struct file_operations epx_c3_fops = {
+	.owner		= THIS_MODULE,
+	.llseek		= no_llseek,
+	.write		= epx_c3_write,
+	.ioctl		= epx_c3_ioctl,
+	.open		= epx_c3_open,
+	.release	= epx_c3_release,
+};
+
+static struct miscdevice epx_c3_miscdev = {
+	.minor		= WATCHDOG_MINOR,
+	.name		= "watchdog",
+	.fops		= &epx_c3_fops,
+};
+
+static struct notifier_block epx_c3_notifier = {
+	.notifier_call = epx_c3_notify_sys,
+};
+
+static const char banner[] __initdata =
+    KERN_INFO PFX "Hardware Watchdog Timer for Winsystems EPX-C3 SBC: 0.1\n";
+
+static int __init watchdog_init(void)
+{
+	int ret;
+
+	ret = register_reboot_notifier(&epx_c3_notifier);
+	if (ret) {
+		printk(KERN_ERR PFX "cannot register reboot notifier "
+			"(err=%d)\n", ret);
+		return ret;
+	}
+
+	ret = misc_register(&epx_c3_miscdev);
+	if (ret) {
+		printk(KERN_ERR PFX "cannot register miscdev on minor=%d "
+			"(err=%d)\n", WATCHDOG_MINOR, ret);
+		unregister_reboot_notifier(&epx_c3_notifier);
+		return ret;
+	}
+
+	printk(banner);
+
+	return 0;
+}
+
+static void __exit watchdog_exit(void)
+{
+	misc_deregister(&epx_c3_miscdev);
+	unregister_reboot_notifier(&epx_c3_notifier);
+}
+
+module_init(watchdog_init);
+module_exit(watchdog_exit);
+
+MODULE_AUTHOR("Calin A. Culianu <calin@ajvar.org>");
+MODULE_DESCRIPTION("Hardware Watchdog Device for Winsystems EPX-C3 SBC.  Note that there is no way to probe for this device -- so only use it if you are *sure* you are runnning on this specific SBC system from Winsystems!  It writes to IO ports 0x1ee and 0x1ef!");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);