power: Add base support for the RK808 PMIC

This Rockchip PMIC provides features suitable for battery-powered
applications. It is commonly used with Rockchip SoCs.

Add a driver which provides register access. The regulator driver will use
this.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/power/pmic/Kconfig b/drivers/power/pmic/Kconfig
index fb29843..8be3c07 100644
--- a/drivers/power/pmic/Kconfig
+++ b/drivers/power/pmic/Kconfig
@@ -33,6 +33,15 @@
 	This config enables implementation of driver-model pmic uclass features
 	for PMIC MAX77686. The driver implements read/write operations.
 
+config PMIC_RK808
+	bool "Enable support for Rockchip PMIC RK808"
+	depends on DM_PMIC
+	---help---
+	The Rockchip RK808 PMIC provides four buck DC-DC convertors, 8 LDOs,
+	an RTC and two low Rds (resistance (drain to source)) switches. It is
+	accessed via an I2C interface. The device is used with Rockchip SoCs.
+	This driver implements register read/write operations.
+
 config PMIC_S2MPS11
 	bool "Enable Driver Model for PMIC Samsung S2MPS11"
 	depends on DM_PMIC