Initial import

1 files changed, 195 insertions, 0 deletions

diff --git a/drivers/watchdog/sa1100_wdt.c b/drivers/watchdog/sa1100_wdt.c
new file mode 100644
index 000000000..e1d39a1e9
--- /dev/null
+++ b/drivers/watchdog/sa1100_wdt.c
@@ -0,0 +1,195 @@
+/*
+ *	Watchdog driver for the SA11x0/PXA2xx
+ *
+ *	(c) Copyright 2000 Oleg Drokin <green@crimea.edu>
+ *	    Based on SoftDog driver by Alan Cox <alan@lxorguk.ukuu.org.uk>
+ *
+ *	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 Oleg Drokin nor iXcelerator.com admit liability nor provide
+ *	warranty for any of this software. This material is provided
+ *	"AS-IS" and at no charge.
+ *
+ *	(c) Copyright 2000           Oleg Drokin <green@crimea.edu>
+ *
+ *	27/11/2000 Initial release
+ */
+
+#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/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/bitops.h>
+#include <linux/uaccess.h>
+#include <linux/timex.h>
+
+#ifdef CONFIG_ARCH_PXA
+#include <mach/regs-ost.h>
+#endif
+
+#include <mach/reset.h>
+#include <mach/hardware.h>
+
+static unsigned long oscr_freq;
+static unsigned long sa1100wdt_users;
+static unsigned int pre_margin;
+static int boot_status;
+
+/*
+ *	Allow only one person to hold it open
+ */
+static int sa1100dog_open(struct inode *inode, struct file *file)
+{
+	if (test_and_set_bit(1, &sa1100wdt_users))
+		return -EBUSY;
+
+	/* Activate SA1100 Watchdog timer */
+	writel_relaxed(readl_relaxed(OSCR) + pre_margin, OSMR3);
+	writel_relaxed(OSSR_M3, OSSR);
+	writel_relaxed(OWER_WME, OWER);
+	writel_relaxed(readl_relaxed(OIER) | OIER_E3, OIER);
+	return nonseekable_open(inode, file);
+}
+
+/*
+ * The watchdog cannot be disabled.
+ *
+ * Previous comments suggested that turning off the interrupt by
+ * clearing OIER[E3] would prevent the watchdog timing out but this
+ * does not appear to be true (at least on the PXA255).
+ */
+static int sa1100dog_release(struct inode *inode, struct file *file)
+{
+	pr_crit("Device closed - timer will not stop\n");
+	clear_bit(1, &sa1100wdt_users);
+	return 0;
+}
+
+static ssize_t sa1100dog_write(struct file *file, const char __user *data,
+						size_t len, loff_t *ppos)
+{
+	if (len)
+		/* Refresh OSMR3 timer. */
+		writel_relaxed(readl_relaxed(OSCR) + pre_margin, OSMR3);
+	return len;
+}
+
+static const struct watchdog_info ident = {
+	.options	= WDIOF_CARDRESET | WDIOF_SETTIMEOUT
+				| WDIOF_KEEPALIVEPING,
+	.identity	= "SA1100/PXA255 Watchdog",
+	.firmware_version	= 1,
+};
+
+static long sa1100dog_ioctl(struct file *file, unsigned int cmd,
+							unsigned long arg)
+{
+	int ret = -ENOTTY;
+	int time;
+	void __user *argp = (void __user *)arg;
+	int __user *p = argp;
+
+	switch (cmd) {
+	case WDIOC_GETSUPPORT:
+		ret = copy_to_user(argp, &ident,
+				   sizeof(ident)) ? -EFAULT : 0;
+		break;
+
+	case WDIOC_GETSTATUS:
+		ret = put_user(0, p);
+		break;
+
+	case WDIOC_GETBOOTSTATUS:
+		ret = put_user(boot_status, p);
+		break;
+
+	case WDIOC_KEEPALIVE:
+		writel_relaxed(readl_relaxed(OSCR) + pre_margin, OSMR3);
+		ret = 0;
+		break;
+
+	case WDIOC_SETTIMEOUT:
+		ret = get_user(time, p);
+		if (ret)
+			break;
+
+		if (time <= 0 || (oscr_freq * (long long)time >= 0xffffffff)) {
+			ret = -EINVAL;
+			break;
+		}
+
+		pre_margin = oscr_freq * time;
+		writel_relaxed(readl_relaxed(OSCR) + pre_margin, OSMR3);
+		/*fall through*/
+
+	case WDIOC_GETTIMEOUT:
+		ret = put_user(pre_margin / oscr_freq, p);
+		break;
+	}
+	return ret;
+}
+
+static const struct file_operations sa1100dog_fops = {
+	.owner		= THIS_MODULE,
+	.llseek		= no_llseek,
+	.write		= sa1100dog_write,
+	.unlocked_ioctl	= sa1100dog_ioctl,
+	.open		= sa1100dog_open,
+	.release	= sa1100dog_release,
+};
+
+static struct miscdevice sa1100dog_miscdev = {
+	.minor		= WATCHDOG_MINOR,
+	.name		= "watchdog",
+	.fops		= &sa1100dog_fops,
+};
+
+static int margin __initdata = 60;		/* (secs) Default is 1 minute */
+
+static int __init sa1100dog_init(void)
+{
+	int ret;
+
+	oscr_freq = get_clock_tick_rate();
+
+	/*
+	 * Read the reset status, and save it for later.  If
+	 * we suspend, RCSR will be cleared, and the watchdog
+	 * reset reason will be lost.
+	 */
+	boot_status = (reset_status & RESET_STATUS_WATCHDOG) ?
+				WDIOF_CARDRESET : 0;
+	pre_margin = oscr_freq * margin;
+
+	ret = misc_register(&sa1100dog_miscdev);
+	if (ret == 0)
+		pr_info("SA1100/PXA2xx Watchdog Timer: timer margin %d sec\n",
+			margin);
+	return ret;
+}
+
+static void __exit sa1100dog_exit(void)
+{
+	misc_deregister(&sa1100dog_miscdev);
+}
+
+module_init(sa1100dog_init);
+module_exit(sa1100dog_exit);
+
+MODULE_AUTHOR("Oleg Drokin <green@crimea.edu>");
+MODULE_DESCRIPTION("SA1100/PXA2xx Watchdog");
+
+module_param(margin, int, 0);
+MODULE_PARM_DESC(margin, "Watchdog margin in seconds (default 60s)");
+
+MODULE_LICENSE("GPL");