watchdog: da9062: fix power management ops

This fixes commit f6c98b0838 ("watchdog: da9062: add power management
ops"). During discussion [1] we agreed that this should be configurable
because it is a device quirk if we can't use the hw watchdog auto
suspend function.

[1] https://lore.kernel.org/linux-watchdog/20191128171931.22563-1-m.felsch@pengutronix.de/

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Fixes: f6c98b0838 ("watchdog: da9062: add power management ops")
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Link: https://lore.kernel.org/r/20200207071518.5559-1-m.felsch@pengutronix.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

drivers/watchdog/da9062_wdt.c

@@ -16,6 +16,7 @@
 #include <linux/jiffies.h>
 #include <linux/mfd/da9062/registers.h>
 #include <linux/mfd/da9062/core.h>
+#include <linux/property.h>
 #include <linux/regmap.h>
 #include <linux/of.h>
 
@@ -31,6 +32,7 @@ static const unsigned int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
 struct da9062_watchdog {
 	struct da9062 *hw;
 	struct watchdog_device wdtdev;
+	bool use_sw_pm;
 };
 
 static unsigned int da9062_wdt_timeout_to_sel(unsigned int secs)
@@ -193,6 +195,8 @@ static int da9062_wdt_probe(struct platform_device *pdev)
 	if (!wdt)
 		return -ENOMEM;
 
+	wdt->use_sw_pm = device_property_present(dev, "dlg,use-sw-pm");
+
 	wdt->hw = chip;
 
 	wdt->wdtdev.info = &da9062_watchdog_info;
@@ -219,6 +223,10 @@ static int da9062_wdt_probe(struct platform_device *pdev)
 static int __maybe_unused da9062_wdt_suspend(struct device *dev)
 {
 	struct watchdog_device *wdd = dev_get_drvdata(dev);
+	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
+
+	if (!wdt->use_sw_pm)
+		return 0;
 
 	if (watchdog_active(wdd))
 		return da9062_wdt_stop(wdd);
@@ -229,6 +237,10 @@ static int __maybe_unused da9062_wdt_suspend(struct device *dev)
 static int __maybe_unused da9062_wdt_resume(struct device *dev)
 {
 	struct watchdog_device *wdd = dev_get_drvdata(dev);
+	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
+
+	if (!wdt->use_sw_pm)
+		return 0;
 
 	if (watchdog_active(wdd))
 		return da9062_wdt_start(wdd);