dm: led: Support "default-state" property

Add support for the device tree property "default-state". This feature
might be useful for LEDs indicating "power on" or similar states.

Note: Even with this commit gpio-leds remain in reset state. That's
because the led_gpio is not probed until DM_FLAG_ACTIVATED is set.

Signed-off-by: Patrick Bruenn <p.bruenn@beckhoff.com>

diff --git a/drivers/led/led_gpio.c b/drivers/led/led_gpio.c
index b26f7a730cf4955c4f2228d3b1a5b4e57cc85794..533587dc47434b12e1ef4477b51d73a53f8f8b98 100644 (file)
--- a/drivers/led/led_gpio.c
+++ b/drivers/led/led_gpio.c
@@ -57,11 +57,25 @@ static int led_gpio_probe(struct udevice *dev)
 {
        struct led_uc_plat *uc_plat = dev_get_uclass_platdata(dev);
        struct led_gpio_priv *priv = dev_get_priv(dev);
+       const char *default_state;
+       int ret;
 
        /* Ignore the top-level LED node */
        if (!uc_plat->label)
                return 0;
-       return gpio_request_by_name(dev, "gpios", 0, &priv->gpio, GPIOD_IS_OUT);
+
+       ret = gpio_request_by_name(dev, "gpios", 0, &priv->gpio, GPIOD_IS_OUT);
+       if (ret)
+               return ret;
+
+       default_state = dev_read_string(dev, "default-state");
+       if (default_state) {
+               if (!strncmp(default_state, "on", 2))
+                       gpio_led_set_state(dev, LEDST_ON);
+               else if (!strncmp(default_state, "off", 3))
+                       gpio_led_set_state(dev, LEDST_OFF);
+       }
+       return 0;
 }
 
 static int led_gpio_remove(struct udevice *dev)