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);