dm: pinctrl: Add pinctrl_decode_pin_config_dm().

pinctrl_decode_pin_config_dm() is basically a feature-equivalent
implementation of pinctrl_decode_pin_config(), which operates
on struct udevice devices and uses the dev_read_*() API.
Signed-off-by: NChristoph Muellner <christoph.muellner@theobroma-systems.com>
Reviewed-by: NPhilipp Tomsich <philipp.tomsich@theobroma-systems.com>

drivers/pinctrl/pinctrl-uclass.c

@@ -27,6 +27,28 @@ int pinctrl_decode_pin_config(const void *blob, int node)
 	return flags;
 }
 
+/*
+ * TODO: this function is temporary for v2019.01.
+ * It should be renamed to pinctrl_decode_pin_config(),
+ * the original pinctrl_decode_pin_config() function should
+ * be removed and all callers of the original function should
+ * be migrated to use the new one.
+ */
+int pinctrl_decode_pin_config_dm(struct udevice *dev)
+{
+	int pinconfig = 0;
+
+	if (dev->uclass->uc_drv->id != UCLASS_PINCONFIG)
+		return -EINVAL;
+
+	if (dev_read_bool(dev, "bias-pull-up"))
+		pinconfig |= 1 << PIN_CONFIG_BIAS_PULL_UP;
+	else if (dev_read_bool(dev, "bias-pull-down"))
+		pinconfig |= 1 << PIN_CONFIG_BIAS_PULL_DOWN;
+
+	return pinconfig;
+}
+
 #if CONFIG_IS_ENABLED(PINCTRL_FULL)
 /**
  * pinctrl_config_one() - apply pinctrl settings for a single node

include/dm/pinctrl.h

@@ -354,6 +354,18 @@ int pinctrl_get_periph_id(struct udevice *dev, struct udevice *periph);
  */
 int pinctrl_decode_pin_config(const void *blob, int node);
 
+/**
+ * pinctrl_decode_pin_config_dm() - decode pin configuration flags
+ *
+ * This decodes some of the PIN_CONFIG values into flags, with each value
+ * being (1 << pin_cfg). This does not support things with values like the
+ * slew rate.
+ *
+ * @pinconfig:	Pinconfig udevice
+ * @return decoded flag value, or -ve on error
+ */
+int pinctrl_decode_pin_config_dm(struct udevice *dev);
+
 /**
  * pinctrl_get_gpio_mux() - get the mux value for a particular GPIO
  *