Merge tag 'sound-3.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai...

[deliverable/linux.git] / drivers / watchdog / imx2_wdt.c

diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c
index 68c3d379ffa8c599333af45abc1b0841fd10059e..7e12f88bb4a688748d52bc0d423182c2434d34a1 100644 (file)
--- a/drivers/watchdog/imx2_wdt.c
+++ b/drivers/watchdog/imx2_wdt.c
@@ -22,14 +22,17 @@
  */
 
 #include <linux/clk.h>
+#include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/jiffies.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
+#include <linux/notifier.h>
 #include <linux/of_address.h>
 #include <linux/platform_device.h>
+#include <linux/reboot.h>
 #include <linux/regmap.h>
 #include <linux/timer.h>
 #include <linux/watchdog.h>
@@ -59,6 +62,7 @@ struct imx2_wdt_device {
        struct regmap *regmap;
        struct timer_list timer;        /* Pings the watchdog when closed */
        struct watchdog_device wdog;
+       struct notifier_block restart_handler;
 };
 
 static bool nowayout = WATCHDOG_NOWAYOUT;
@@ -77,6 +81,31 @@ static const struct watchdog_info imx2_wdt_info = {
        .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
 };
 
+static int imx2_restart_handler(struct notifier_block *this, unsigned long mode,
+                               void *cmd)
+{
+       unsigned int wcr_enable = IMX2_WDT_WCR_WDE;
+       struct imx2_wdt_device *wdev = container_of(this,
+                                                   struct imx2_wdt_device,
+                                                   restart_handler);
+       /* Assert SRS signal */
+       regmap_write(wdev->regmap, 0, wcr_enable);
+       /*
+        * Due to imx6q errata ERR004346 (WDOG: WDOG SRS bit requires to be
+        * written twice), we add another two writes to ensure there must be at
+        * least two writes happen in the same one 32kHz clock period.  We save
+        * the target check here, since the writes shouldn't be a huge burden
+        * for other platforms.
+        */
+       regmap_write(wdev->regmap, 0, wcr_enable);
+       regmap_write(wdev->regmap, 0, wcr_enable);
+
+       /* wait for reset to assert... */
+       mdelay(500);
+
+       return NOTIFY_DONE;
+}
+
 static inline void imx2_wdt_setup(struct watchdog_device *wdog)
 {
        struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
@@ -191,12 +220,10 @@ static struct regmap_config imx2_wdt_regmap_config = {
 
 static int __init imx2_wdt_probe(struct platform_device *pdev)
 {
-       struct device_node *np = pdev->dev.of_node;
        struct imx2_wdt_device *wdev;
        struct watchdog_device *wdog;
        struct resource *res;
        void __iomem *base;
-       bool big_endian;
        int ret;
        u32 val;
 
@@ -204,10 +231,6 @@ static int __init imx2_wdt_probe(struct platform_device *pdev)
        if (!wdev)
                return -ENOMEM;
 
-       big_endian = of_property_read_bool(np, "big-endian");
-       if (big_endian)
-               imx2_wdt_regmap_config.val_format_endian = REGMAP_ENDIAN_BIG;
-
        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        base = devm_ioremap_resource(&pdev->dev, res);
        if (IS_ERR(base))
@@ -257,6 +280,12 @@ static int __init imx2_wdt_probe(struct platform_device *pdev)
                return ret;
        }
 
+       wdev->restart_handler.notifier_call = imx2_restart_handler;
+       wdev->restart_handler.priority = 128;
+       ret = register_restart_handler(&wdev->restart_handler);
+       if (ret)
+               dev_err(&pdev->dev, "cannot register restart handler\n");
+
        dev_info(&pdev->dev, "timeout %d sec (nowayout=%d)\n",
                 wdog->timeout, nowayout);
 
@@ -268,6 +297,8 @@ static int __exit imx2_wdt_remove(struct platform_device *pdev)
        struct watchdog_device *wdog = platform_get_drvdata(pdev);
        struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
 
+       unregister_restart_handler(&wdev->restart_handler);
+
        watchdog_unregister_device(wdog);
 
        if (imx2_wdt_is_running(wdev)) {