regulator: tps65090: add external control support for DCDC

The TPS65090's DCDC output can also be enable/disable through the
external digital input signal. Add support for enable/disable
either through register access via I2C or through external
control inputs. The external control inputs can be driven through
GPIOs also and hence adding support for passing the GPIO number.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/include/linux/mfd/tps65090.h b/include/linux/mfd/tps65090.h
index 59892122..804e280 100644
--- a/include/linux/mfd/tps65090.h
+++ b/include/linux/mfd/tps65090.h
@@ -64,10 +64,15 @@
  * struct tps65090_regulator_plat_data
  *
  * @reg_init_data: The regulator init data.
+ * @enable_ext_control: Enable extrenal control or not. Only available for
+ *     DCDC1, DCDC2 and DCDC3.
+ * @gpio: Gpio number if external control is enabled and controlled through
+ *     gpio.
  */
-
 struct tps65090_regulator_plat_data {
 	struct regulator_init_data *reg_init_data;
+	bool enable_ext_control;
+	int gpio;
 };
 
 struct tps65090_platform_data {