watchdog: rzg2l_wdt: Rely on the reset driver for doing proper reset

The reset driver has been adapted in commit da235d2f
("clk: renesas: rzg2l: Check reset monitor registers") to check the reset
monitor bits before declaring reset asserts/de-asserts as
successful/failure operations. With that, there is no need to keep the
reset workaround for RZ/V2M in place in the watchdog driver.
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20240531065723.1085423-8-claudiu.beznea.uj@bp.renesas.comSigned-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

drivers/watchdog/rzg2l_wdt.c

@@ -8,7 +8,6 @@
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/io.h>
-#include <linux/iopoll.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
@@ -54,35 +53,11 @@ struct rzg2l_wdt_priv {
 	struct reset_control *rstc;
 	unsigned long osc_clk_rate;
 	unsigned long delay;
-	unsigned long minimum_assertion_period;
 	struct clk *pclk;
 	struct clk *osc_clk;
 	enum rz_wdt_type devtype;
 };
 
-static int rzg2l_wdt_reset(struct rzg2l_wdt_priv *priv)
-{
-	int err, status;
-
-	if (priv->devtype == WDT_RZV2M) {
-		/* WDT needs TYPE-B reset control */
-		err = reset_control_assert(priv->rstc);
-		if (err)
-			return err;
-		ndelay(priv->minimum_assertion_period);
-		err = reset_control_deassert(priv->rstc);
-		if (err)
-			return err;
-		err = read_poll_timeout(reset_control_status, status,
-					status != 1, 0, 1000, false,
-					priv->rstc);
-	} else {
-		err = reset_control_reset(priv->rstc);
-	}
-
-	return err;
-}
-
 static void rzg2l_wdt_wait_delay(struct rzg2l_wdt_priv *priv)
 {
 	/* delay timer when change the setting register */
@@ -189,13 +164,12 @@ 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;
 
 	clk_prepare_enable(priv->pclk);
 	clk_prepare_enable(priv->osc_clk);
 
 	if (priv->devtype == WDT_RZG2L) {
-		int ret;
-
 		ret = reset_control_deassert(priv->rstc);
 		if (ret)
 			return ret;
@@ -207,7 +181,9 @@ static int rzg2l_wdt_restart(struct watchdog_device *wdev,
 		rzg2l_wdt_write(priv, PEEN_FORCE, PEEN);
 	} else {
 		/* RZ/V2M doesn't have parity error registers */
-		rzg2l_wdt_reset(priv);
+		ret = reset_control_reset(priv->rstc);
+		if (ret)
+			return ret;
 
 		wdev->timeout = 0;
 
@@ -299,13 +275,6 @@ static int rzg2l_wdt_probe(struct platform_device *pdev)
 
 	priv->devtype = (uintptr_t)of_device_get_match_data(dev);
 
-	if (priv->devtype == WDT_RZV2M) {
-		priv->minimum_assertion_period = RZV2M_A_NSEC +
-			3 * F2CYCLE_NSEC(pclk_rate) + 5 *
-			max(F2CYCLE_NSEC(priv->osc_clk_rate),
-			    F2CYCLE_NSEC(pclk_rate));
-	}
-
 	pm_runtime_enable(&pdev->dev);
 
 	priv->wdev.info = &rzg2l_wdt_ident;