[PATCH v3, 1/2] driver: watchdog: reset watchdog in designware_wdt_stop() function

[Meng.Li at windriver.com]

From: MengLi <meng.li at windriver.com>

In uboot command line environment, watchdog is not able to be
stopped with below commands:
SOCFPGA_STRATIX10 # wdt dev watchdog at ffd00200
SOCFPGA_STRATIX10 # wdt stop
Refer to watchdog driver in linux kernel, it is also need to reset
watchdog after disable it so that the disable action takes effect.

Signed-off-by: Meng Li <Meng.Li at windriver.com>
Reviewed-by: Stefan Roese <sr at denx.de>
Reviewed-by: Sean Anderson <sean.anderson at seco.com>

---
v3:
Add the resets to designware_wdt_priv and initialize it in probe().
v2:
Change "#if CONFIG_IS_ENABLED(DM_RESET)" into
"if (CONFIG_IS_ENABLED(DM_RESET)) {", and define the variable
into if condition sentence.
---
 drivers/watchdog/designware_wdt.c | 31 +++++++++++++++++++++----------
 1 file changed, 21 insertions(+), 10 deletions(-)

diff --git a/drivers/watchdog/designware_wdt.c b/drivers/watchdog/designware_wdt.c
index 12f09a7a39..cdf6b5709b 100644
--- a/drivers/watchdog/designware_wdt.c
+++ b/drivers/watchdog/designware_wdt.c
@@ -23,6 +23,7 @@
 struct designware_wdt_priv {
 	void __iomem	*base;
 	unsigned int	clk_khz;
+	struct reset_ctl_bulk *resets;
 };
 
 /*
@@ -96,6 +97,18 @@ static int designware_wdt_stop(struct udevice *dev)
 	designware_wdt_reset(dev);
 	writel(0, priv->base + DW_WDT_CR);
 
+        if (CONFIG_IS_ENABLED(DM_RESET)) {
+		int ret;
+
+		ret = reset_assert_bulk(priv->resets);
+		if (ret)
+			return ret;
+
+		ret = reset_deassert_bulk(priv->resets);
+		if (ret)
+			return ret;
+	}
+
 	return 0;
 }
 
@@ -137,17 +150,15 @@ static int designware_wdt_probe(struct udevice *dev)
 	priv->clk_khz = CONFIG_DW_WDT_CLOCK_KHZ;
 #endif
 
-#if CONFIG_IS_ENABLED(DM_RESET)
-	struct reset_ctl_bulk resets;
+	if (CONFIG_IS_ENABLED(DM_RESET)) {
+		ret = reset_get_bulk(dev, priv->resets);
+		if (ret)
+			return ret;
 
-	ret = reset_get_bulk(dev, &resets);
-	if (ret)
-		return ret;
-
-	ret = reset_deassert_bulk(&resets);
-	if (ret)
-		return ret;
-#endif
+		ret = reset_deassert_bulk(priv->resets);
+		if (ret)
+			return ret;
+	}
 
 	/* reset to disable the watchdog */
 	return designware_wdt_stop(dev);
-- 
2.17.1