1 files changed, 322 insertions, 0 deletions
diff --git a/drivers/watchdog/orion_wdt.c b/drivers/watchdog/orion_wdt.c
new file mode 100644
index 000000000000..2d9fb96a9ee9
--- /dev/null
+++ b/drivers/watchdog/orion_wdt.c
@@ -0,0 +1,322 @@
+/*
+ * drivers/watchdog/orion_wdt.c
+ *
+ * Watchdog driver for Orion/Kirkwood processors
+ *
+ * Author: Sylver Bruneau <sylver.bruneau@googlemail.com>
+ *
+ * This file is licensed under  the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#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/platform_device.h>
+#include <linux/watchdog.h>
+#include <linux/init.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+#include <mach/bridge-regs.h>
+#include <plat/orion_wdt.h>
+
+/*
+ * Watchdog timer block registers.
+ */
+#define TIMER_CTRL		(TIMER_VIRT_BASE + 0x0000)
+#define  WDT_EN			0x0010
+#define WDT_VAL			(TIMER_VIRT_BASE + 0x0024)
+
+#define WDT_MAX_CYCLE_COUNT	0xffffffff
+#define WDT_IN_USE		0
+#define WDT_OK_TO_CLOSE		1
+
+static int nowayout = WATCHDOG_NOWAYOUT;
+static int heartbeat = -1;		/* module parameter (seconds) */
+static unsigned int wdt_max_duration;	/* (seconds) */
+static unsigned int wdt_tclk;
+static unsigned long wdt_status;
+static spinlock_t wdt_lock;
+
+static void orion_wdt_ping(void)
+{
+	spin_lock(&wdt_lock);
+
+	/* Reload watchdog duration */
+	writel(wdt_tclk * heartbeat, WDT_VAL);
+
+	spin_unlock(&wdt_lock);
+}
+
+static void orion_wdt_enable(void)
+{
+	u32 reg;
+
+	spin_lock(&wdt_lock);
+
+	/* Set watchdog duration */
+	writel(wdt_tclk * heartbeat, WDT_VAL);
+
+	/* Clear watchdog timer interrupt */
+	reg = readl(BRIDGE_CAUSE);
+	reg &= ~WDT_INT_REQ;
+	writel(reg, BRIDGE_CAUSE);
+
+	/* Enable watchdog timer */
+	reg = readl(TIMER_CTRL);
+	reg |= WDT_EN;
+	writel(reg, TIMER_CTRL);
+
+	/* Enable reset on watchdog */
+	reg = readl(RSTOUTn_MASK);
+	reg |= WDT_RESET_OUT_EN;
+	writel(reg, RSTOUTn_MASK);
+
+	spin_unlock(&wdt_lock);
+}
+
+static void orion_wdt_disable(void)
+{
+	u32 reg;
+
+	spin_lock(&wdt_lock);
+
+	/* Disable reset on watchdog */
+	reg = readl(RSTOUTn_MASK);
+	reg &= ~WDT_RESET_OUT_EN;
+	writel(reg, RSTOUTn_MASK);
+
+	/* Disable watchdog timer */
+	reg = readl(TIMER_CTRL);
+	reg &= ~WDT_EN;
+	writel(reg, TIMER_CTRL);
+
+	spin_unlock(&wdt_lock);
+}
+
+static int orion_wdt_get_timeleft(int *time_left)
+{
+	spin_lock(&wdt_lock);
+	*time_left = readl(WDT_VAL) / wdt_tclk;
+	spin_unlock(&wdt_lock);
+	return 0;
+}
+
+static int orion_wdt_open(struct inode *inode, struct file *file)
+{
+	if (test_and_set_bit(WDT_IN_USE, &wdt_status))
+		return -EBUSY;
+	clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
+	orion_wdt_enable();
+	return nonseekable_open(inode, file);
+}
+
+static ssize_t orion_wdt_write(struct file *file, const char *data,
+					size_t len, loff_t *ppos)
+{
+	if (len) {
+		if (!nowayout) {
+			size_t i;
+
+			clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
+			for (i = 0; i != len; i++) {
+				char c;
+
+				if (get_user(c, data + i))
+					return -EFAULT;
+				if (c == 'V')
+					set_bit(WDT_OK_TO_CLOSE, &wdt_status);
+			}
+		}
+		orion_wdt_ping();
+	}
+	return len;
+}
+
+static int orion_wdt_settimeout(int new_time)
+{
+	if ((new_time <= 0) || (new_time > wdt_max_duration))
+		return -EINVAL;
+
+	/* Set new watchdog time to be used when
+	 * orion_wdt_enable() or orion_wdt_ping() is called. */
+	heartbeat = new_time;
+	return 0;
+}
+
+static const struct watchdog_info ident = {
+	.options	= WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT |
+			  WDIOF_KEEPALIVEPING,
+	.identity	= "Orion Watchdog",
+};
+
+static long orion_wdt_ioctl(struct file *file, unsigned int cmd,
+				unsigned long arg)
+{
+	int ret = -ENOTTY;
+	int time;
+
+	switch (cmd) {
+	case WDIOC_GETSUPPORT:
+		ret = copy_to_user((struct watchdog_info *)arg, &ident,
+				   sizeof(ident)) ? -EFAULT : 0;
+		break;
+
+	case WDIOC_GETSTATUS:
+	case WDIOC_GETBOOTSTATUS:
+		ret = put_user(0, (int *)arg);
+		break;
+
+	case WDIOC_KEEPALIVE:
+		orion_wdt_ping();
+		ret = 0;
+		break;
+
+	case WDIOC_SETTIMEOUT:
+		ret = get_user(time, (int *)arg);
+		if (ret)
+			break;
+
+		if (orion_wdt_settimeout(time)) {
+			ret = -EINVAL;
+			break;
+		}
+		orion_wdt_ping();
+		/* Fall through */
+
+	case WDIOC_GETTIMEOUT:
+		ret = put_user(heartbeat, (int *)arg);
+		break;
+
+	case WDIOC_GETTIMELEFT:
+		if (orion_wdt_get_timeleft(&time)) {
+			ret = -EINVAL;
+			break;
+		}
+		ret = put_user(time, (int *)arg);
+		break;
+	}
+	return ret;
+}
+
+static int orion_wdt_release(struct inode *inode, struct file *file)
+{
+	if (test_bit(WDT_OK_TO_CLOSE, &wdt_status))
+		orion_wdt_disable();
+	else
+		printk(KERN_CRIT "WATCHDOG: Device closed unexpectedly - "
+					"timer will not stop\n");
+	clear_bit(WDT_IN_USE, &wdt_status);
+	clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
+
+	return 0;
+}
+
+
+static const struct file_operations orion_wdt_fops = {
+	.owner		= THIS_MODULE,
+	.llseek		= no_llseek,
+	.write		= orion_wdt_write,
+	.unlocked_ioctl	= orion_wdt_ioctl,
+	.open		= orion_wdt_open,
+	.release	= orion_wdt_release,
+};
+
+static struct miscdevice orion_wdt_miscdev = {
+	.minor		= WATCHDOG_MINOR,
+	.name		= "watchdog",
+	.fops		= &orion_wdt_fops,
+};
+
+static int __devinit orion_wdt_probe(struct platform_device *pdev)
+{
+	struct orion_wdt_platform_data *pdata = pdev->dev.platform_data;
+	int ret;
+
+	if (pdata) {
+		wdt_tclk = pdata->tclk;
+	} else {
+		printk(KERN_ERR "Orion Watchdog misses platform data\n");
+		return -ENODEV;
+	}
+
+	if (orion_wdt_miscdev.parent)
+		return -EBUSY;
+	orion_wdt_miscdev.parent = &pdev->dev;
+
+	wdt_max_duration = WDT_MAX_CYCLE_COUNT / wdt_tclk;
+	if (orion_wdt_settimeout(heartbeat))
+		heartbeat = wdt_max_duration;
+
+	ret = misc_register(&orion_wdt_miscdev);
+	if (ret)
+		return ret;
+
+	printk(KERN_INFO "Orion Watchdog Timer: Initial timeout %d sec%s\n",
+				heartbeat, nowayout ? ", nowayout" : "");
+	return 0;
+}
+
+static int __devexit orion_wdt_remove(struct platform_device *pdev)
+{
+	int ret;
+
+	if (test_bit(WDT_IN_USE, &wdt_status)) {
+		orion_wdt_disable();
+		clear_bit(WDT_IN_USE, &wdt_status);
+	}
+
+	ret = misc_deregister(&orion_wdt_miscdev);
+	if (!ret)
+		orion_wdt_miscdev.parent = NULL;
+
+	return ret;
+}
+
+static void orion_wdt_shutdown(struct platform_device *pdev)
+{
+	if (test_bit(WDT_IN_USE, &wdt_status))
+		orion_wdt_disable();
+}
+
+static struct platform_driver orion_wdt_driver = {
+	.probe		= orion_wdt_probe,
+	.remove		= __devexit_p(orion_wdt_remove),
+	.shutdown	= orion_wdt_shutdown,
+	.driver		= {
+		.owner	= THIS_MODULE,
+		.name	= "orion_wdt",
+	},
+};
+
+static int __init orion_wdt_init(void)
+{
+	spin_lock_init(&wdt_lock);
+	return platform_driver_register(&orion_wdt_driver);
+}
+
+static void __exit orion_wdt_exit(void)
+{
+	platform_driver_unregister(&orion_wdt_driver);
+}
+
+module_init(orion_wdt_init);
+module_exit(orion_wdt_exit);
+
+MODULE_AUTHOR("Sylver Bruneau <sylver.bruneau@googlemail.com>");
+MODULE_DESCRIPTION("Orion Processor Watchdog");
+
+module_param(heartbeat, int, 0);
+MODULE_PARM_DESC(heartbeat, "Initial watchdog heartbeat in seconds");
+
+module_param(nowayout, int, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
+				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);