power: reset: gpio-poweroff: add ability to specific active and inactive delays

Similar to gpio-reset allow to specify active and inactive delays
while keeping the 100ms defaults that were used previously all the time.

The dt-properties are named the same as in gpio-reset but get an "-ms"
suffix as properties should contain such a suffix specifying its unit.
Signed-off-by: Heiko Stuebner <heiko.stuebner@bq.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Moritz Fischer <mdf@kernel.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

Documentation/devicetree/bindings/power/reset/gpio-poweroff.txt

@@ -27,6 +27,8 @@ Optional properties:
   it to an output when the power-off handler is called. If this optional
   property is not specified, the GPIO is initialized as an output in its
   inactive state.
+- active-delay-ms: Delay (default 100) to wait after driving gpio active
+- inactive-delay-ms: Delay (default 100) to wait after driving gpio inactive
 - timeout-ms: Time to wait before asserting a WARN_ON(1). If nothing is
               specified, 3000 ms is used.
 

drivers/power/reset/gpio-poweroff.c

@@ -26,6 +26,8 @@
  */
 static struct gpio_desc *reset_gpio;
 static u32 timeout = DEFAULT_TIMEOUT_MS;
+static u32 active_delay = 100;
+static u32 inactive_delay = 100;
 
 static void gpio_poweroff_do_poweroff(void)
 {
@@ -33,10 +35,11 @@ static void gpio_poweroff_do_poweroff(void)
 
 	/* drive it active, also inactive->active edge */
 	gpiod_direction_output(reset_gpio, 1);
-	mdelay(100);
+	mdelay(active_delay);
+
 	/* drive inactive, also active->inactive edge */
 	gpiod_set_value_cansleep(reset_gpio, 0);
-	mdelay(100);
+	mdelay(inactive_delay);
 
 	/* drive it active, also inactive->active edge */
 	gpiod_set_value_cansleep(reset_gpio, 1);
@@ -66,6 +69,9 @@ static int gpio_poweroff_probe(struct platform_device *pdev)
 	else
 		flags = GPIOD_OUT_LOW;
 
+	device_property_read_u32(&pdev->dev, "active-delay-ms", &active_delay);
+	device_property_read_u32(&pdev->dev, "inactive-delay-ms",
+				 &inactive_delay);
 	device_property_read_u32(&pdev->dev, "timeout-ms", &timeout);
 
 	reset_gpio = devm_gpiod_get(&pdev->dev, NULL, flags);