[PATCH v2 4/4] watchdog: rzg2l_wdt: Use force reset for WDT reset

[Biju Das <biju.das.jz@xxxxxxxxxxxxxx>]

This patch uses the force reset(WDTRSTB) for triggering WDT reset
(WDTRSTB). This method is faster compared to the overflow method
for triggering watchdog reset.

Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
---
V1->V2:
 * Updated the commit description.
---
 drivers/watchdog/rzg2l_wdt.c | 21 +++++++--------------
 1 file changed, 7 insertions(+), 14 deletions(-)

diff --git a/drivers/watchdog/rzg2l_wdt.c b/drivers/watchdog/rzg2l_wdt.c
index d1b5cb70d56c..94f98825ab8d 100644
--- a/drivers/watchdog/rzg2l_wdt.c
+++ b/drivers/watchdog/rzg2l_wdt.c
@@ -21,8 +21,11 @@
 #define WDTSET		0x04
 #define WDTTIM		0x08
 #define WDTINT		0x0C
+#define PECR		0x10
+#define PEEN		0x14
 #define WDTCNT_WDTEN	BIT(0)
 #define WDTINT_INTDISP	BIT(0)
+#define PEEN_FORCE_RST	BIT(0)
 
 #define WDT_DEFAULT_TIMEOUT		60U
 
@@ -141,22 +144,12 @@ static int rzg2l_wdt_restart(struct watchdog_device *wdev,
 			     unsigned long action, void *data)
 {
 	struct rzg2l_wdt_priv *priv = watchdog_get_drvdata(wdev);
-	int ret;
 
-	/* Reset the module before we modify any register */
-	ret = reset_control_reset(priv->rstc);
-	if (ret) {
-		dev_err(wdev->parent, "failed to reset");
-		return ret;
-	}
+	/* Generate Reset (WDTRSTB) Signal */
+	rzg2l_wdt_write(priv, 0, PECR);
 
-	pm_runtime_get_sync(wdev->parent);
-
-	/* smallest counter value to reboot soon */
-	rzg2l_wdt_write(priv, WDTSET_COUNTER_VAL(1), WDTSET);
-
-	/* Enable watchdog timer*/
-	rzg2l_wdt_write(priv, WDTCNT_WDTEN, WDTCNT);
+	/* Force reset (WDTRSTB) */
+	rzg2l_wdt_write(priv, PEEN_FORCE_RST, PEEN);
 
 	return 0;
 }
-- 
2.17.1