1 files changed, 285 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-ds1374.c b/drivers/rtc/rtc-ds1374.c
index 9e6e14fb53d7..8605fde394b2 100644
--- a/drivers/rtc/rtc-ds1374.c
+++ b/drivers/rtc/rtc-ds1374.c
@@ -4,6 +4,7 @@
  * Based on code by Randy Vinson <rvinson@mvista.com>,
  * which was based on the m41t00.c by Mark Greer <mgreer@mvista.com>.
  *
+ * Copyright (C) 2014 Rose Technology
  * Copyright (C) 2006-2007 Freescale Semiconductor
  *
  * 2005 (c) MontaVista Software, Inc. This file is licensed under
@@ -26,6 +27,13 @@
 #include <linux/workqueue.h>
 #include <linux/slab.h>
 #include <linux/pm.h>
+#ifdef CONFIG_RTC_DRV_DS1374_WDT
+#include <linux/fs.h>
+#include <linux/ioctl.h>
+#include <linux/miscdevice.h>
+#include <linux/reboot.h>
+#include <linux/watchdog.h>
+#endif
 
 #define DS1374_REG_TOD0         0x00 /* Time of Day */
 #define DS1374_REG_TOD1         0x01
@@ -49,6 +57,14 @@ static const struct i2c_device_id ds1374_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, ds1374_id);
 
+#ifdef CONFIG_OF
+static const struct of_device_id ds1374_of_match[] = {
+        { .compatible = "dallas,ds1374" },
+        { }
+};
+MODULE_DEVICE_TABLE(of, ds1374_of_match);
+#endif
+
 struct ds1374 {
         struct i2c_client *client;
         struct rtc_device *rtc;
@@ -162,6 +178,7 @@ static int ds1374_set_time(struct device *dev, struct rtc_time *time)
         return ds1374_write_rtc(client, itime, DS1374_REG_TOD0, 4);
 }
 
+#ifndef CONFIG_RTC_DRV_DS1374_WDT
 /* The ds1374 has a decrementer for an alarm, rather than a comparator.
  * If the time of day is changed, then the alarm will need to be
  * reset.
@@ -263,6 +280,7 @@ out:
         mutex_unlock(&ds1374->mutex);
         return ret;
 }
+#endif
 
 static irqreturn_t ds1374_irq(int irq, void *dev_id)
 {
@@ -307,6 +325,7 @@ unlock:
         mutex_unlock(&ds1374->mutex);
 }
 
+#ifndef CONFIG_RTC_DRV_DS1374_WDT
 static int ds1374_alarm_irq_enable(struct device *dev, unsigned int enabled)
 {
         struct i2c_client *client = to_i2c_client(dev);
@@ -331,15 +350,260 @@ out:
         mutex_unlock(&ds1374->mutex);
         return ret;
 }
+#endif
 
 static const struct rtc_class_ops ds1374_rtc_ops = {
         .read_time = ds1374_read_time,
         .set_time = ds1374_set_time,
+#ifndef CONFIG_RTC_DRV_DS1374_WDT
         .read_alarm = ds1374_read_alarm,
         .set_alarm = ds1374_set_alarm,
         .alarm_irq_enable = ds1374_alarm_irq_enable,
+#endif
+};
+
+#ifdef CONFIG_RTC_DRV_DS1374_WDT
+/*
+ *****************************************************************************
+ *
+ * Watchdog Driver
+ *
+ *****************************************************************************
+ */
+static struct i2c_client *save_client;
+/* Default margin */
+#define WD_TIMO 131762
+
+#define DRV_NAME "DS1374 Watchdog"
+
+static int wdt_margin = WD_TIMO;
+static unsigned long wdt_is_open;
+module_param(wdt_margin, int, 0);
+MODULE_PARM_DESC(wdt_margin, "Watchdog timeout in seconds (default 32s)");
+
+static const struct watchdog_info ds1374_wdt_info = {
+        .identity       = "DS1374 WTD",
+        .options        = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING |
+                                                WDIOF_MAGICCLOSE,
 };
 
+static int ds1374_wdt_settimeout(unsigned int timeout)
+{
+        int ret = -ENOIOCTLCMD;
+        int cr;
+
+        ret = cr = i2c_smbus_read_byte_data(save_client, DS1374_REG_CR);
+        if (ret < 0)
+                goto out;
+
+        /* Disable any existing watchdog/alarm before setting the new one */
+        cr &= ~DS1374_REG_CR_WACE;
+
+        ret = i2c_smbus_write_byte_data(save_client, DS1374_REG_CR, cr);
+        if (ret < 0)
+                goto out;
+
+        /* Set new watchdog time */
+        ret = ds1374_write_rtc(save_client, timeout, DS1374_REG_WDALM0, 3);
+        if (ret) {
+                pr_info("rtc-ds1374 - couldn't set new watchdog time\n");
+                goto out;
+        }
+
+        /* Enable watchdog timer */
+        cr |= DS1374_REG_CR_WACE | DS1374_REG_CR_WDALM;
+        cr &= ~DS1374_REG_CR_AIE;
+
+        ret = i2c_smbus_write_byte_data(save_client, DS1374_REG_CR, cr);
+        if (ret < 0)
+                goto out;
+
+        return 0;
+out:
+        return ret;
+}
+
+
+/*
+ * Reload the watchdog timer.  (ie, pat the watchdog)
+ */
+static void ds1374_wdt_ping(void)
+{
+        u32 val;
+        int ret = 0;
+
+        ret = ds1374_read_rtc(save_client, &val, DS1374_REG_WDALM0, 3);
+        if (ret)
+                pr_info("WD TICK FAIL!!!!!!!!!! %i\n", ret);
+}
+
+static void ds1374_wdt_disable(void)
+{
+        int ret = -ENOIOCTLCMD;
+        int cr;
+
+        cr = i2c_smbus_read_byte_data(save_client, DS1374_REG_CR);
+        /* Disable watchdog timer */
+        cr &= ~DS1374_REG_CR_WACE;
+
+        ret = i2c_smbus_write_byte_data(save_client, DS1374_REG_CR, cr);
+}
+
+/*
+ * Watchdog device is opened, and watchdog starts running.
+ */
+static int ds1374_wdt_open(struct inode *inode, struct file *file)
+{
+        struct ds1374 *ds1374 = i2c_get_clientdata(save_client);
+
+        if (MINOR(inode->i_rdev) == WATCHDOG_MINOR) {
+                mutex_lock(&ds1374->mutex);
+                if (test_and_set_bit(0, &wdt_is_open)) {
+                        mutex_unlock(&ds1374->mutex);
+                        return -EBUSY;
+                }
+                /*
+                 *      Activate
+                 */
+                wdt_is_open = 1;
+                mutex_unlock(&ds1374->mutex);
+                return nonseekable_open(inode, file);
+        }
+        return -ENODEV;
+}
+
+/*
+ * Close the watchdog device.
+ */
+static int ds1374_wdt_release(struct inode *inode, struct file *file)
+{
+        if (MINOR(inode->i_rdev) == WATCHDOG_MINOR)
+                clear_bit(0, &wdt_is_open);
+
+        return 0;
+}
+
+/*
+ * Pat the watchdog whenever device is written to.
+ */
+static ssize_t ds1374_wdt_write(struct file *file, const char __user *data,
+                                size_t len, loff_t *ppos)
+{
+        if (len) {
+                ds1374_wdt_ping();
+                return 1;
+        }
+        return 0;
+}
+
+static ssize_t ds1374_wdt_read(struct file *file, char __user *data,
+                                size_t len, loff_t *ppos)
+{
+        return 0;
+}
+
+/*
+ * Handle commands from user-space.
+ */
+static long ds1374_wdt_ioctl(struct file *file, unsigned int cmd,
+                                                        unsigned long arg)
+{
+        int new_margin, options;
+
+        switch (cmd) {
+        case WDIOC_GETSUPPORT:
+                return copy_to_user((struct watchdog_info __user *)arg,
+                &ds1374_wdt_info, sizeof(ds1374_wdt_info)) ? -EFAULT : 0;
+
+        case WDIOC_GETSTATUS:
+        case WDIOC_GETBOOTSTATUS:
+                return put_user(0, (int __user *)arg);
+        case WDIOC_KEEPALIVE:
+                ds1374_wdt_ping();
+                return 0;
+        case WDIOC_SETTIMEOUT:
+                if (get_user(new_margin, (int __user *)arg))
+                        return -EFAULT;
+
+                if (new_margin < 1 || new_margin > 16777216)
+                        return -EINVAL;
+
+                wdt_margin = new_margin;
+                ds1374_wdt_settimeout(new_margin);
+                ds1374_wdt_ping();
+                /* fallthrough */
+        case WDIOC_GETTIMEOUT:
+                return put_user(wdt_margin, (int __user *)arg);
+        case WDIOC_SETOPTIONS:
+                if (copy_from_user(&options, (int __user *)arg, sizeof(int)))
+                        return -EFAULT;
+
+                if (options & WDIOS_DISABLECARD) {
+                        pr_info("rtc-ds1374: disable watchdog\n");
+                        ds1374_wdt_disable();
+                }
+
+                if (options & WDIOS_ENABLECARD) {
+                        pr_info("rtc-ds1374: enable watchdog\n");
+                        ds1374_wdt_settimeout(wdt_margin);
+                        ds1374_wdt_ping();
+                }
+
+                return -EINVAL;
+        }
+        return -ENOTTY;
+}
+
+static long ds1374_wdt_unlocked_ioctl(struct file *file, unsigned int cmd,
+                        unsigned long arg)
+{
+        int ret;
+        struct ds1374 *ds1374 = i2c_get_clientdata(save_client);
+
+        mutex_lock(&ds1374->mutex);
+        ret = ds1374_wdt_ioctl(file, cmd, arg);
+        mutex_unlock(&ds1374->mutex);
+
+        return ret;
+}
+
+static int ds1374_wdt_notify_sys(struct notifier_block *this,
+                        unsigned long code, void *unused)
+{
+        if (code == SYS_DOWN || code == SYS_HALT)
+                /* Disable Watchdog */
+                ds1374_wdt_disable();
+        return NOTIFY_DONE;
+}
+
+static const struct file_operations ds1374_wdt_fops = {
+        .owner                  = THIS_MODULE,
+        .read                   = ds1374_wdt_read,
+        .unlocked_ioctl         = ds1374_wdt_unlocked_ioctl,
+        .write                  = ds1374_wdt_write,
+        .open                   = ds1374_wdt_open,
+        .release                = ds1374_wdt_release,
+        .llseek                 = no_llseek,
+};
+
+static struct miscdevice ds1374_miscdev = {
+        .minor          = WATCHDOG_MINOR,
+        .name           = "watchdog",
+        .fops           = &ds1374_wdt_fops,
+};
+
+static struct notifier_block ds1374_wdt_notifier = {
+        .notifier_call = ds1374_wdt_notify_sys,
+};
+
+#endif /*CONFIG_RTC_DRV_DS1374_WDT*/
+/*
+ *****************************************************************************
+ *
+ *      Driver Interface
+ *
+ *****************************************************************************
+ */
 static int ds1374_probe(struct i2c_client *client,
                         const struct i2c_device_id *id)
 {
@@ -378,12 +642,33 @@ static int ds1374_probe(struct i2c_client *client,
                 return PTR_ERR(ds1374->rtc);
         }
 
+#ifdef CONFIG_RTC_DRV_DS1374_WDT
+        save_client = client;
+        ret = misc_register(&ds1374_miscdev);
+        if (ret)
+                return ret;
+        ret = register_reboot_notifier(&ds1374_wdt_notifier);
+        if (ret) {
+                misc_deregister(&ds1374_miscdev);
+                return ret;
+        }
+        ds1374_wdt_settimeout(131072);
+#endif
+
         return 0;
 }
 
 static int ds1374_remove(struct i2c_client *client)
 {
         struct ds1374 *ds1374 = i2c_get_clientdata(client);
+#ifdef CONFIG_RTC_DRV_DS1374_WDT
+        int res;
+
+        res = misc_deregister(&ds1374_miscdev);
+        if (!res)
+                ds1374_miscdev.parent = NULL;
+        unregister_reboot_notifier(&ds1374_wdt_notifier);
+#endif
 
         if (client->irq > 0) {
                 mutex_lock(&ds1374->mutex);