power: pmic: add the base TPS80031 PMIC support

Add support to bind the regulators/child nodes with the pmic.
Also adds the pmic i2c based read/write functions to access pmic
registers.

Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/power/pmic/Kconfig b/drivers/power/pmic/Kconfig
index 54665d7..454a6e0 100644
--- a/drivers/power/pmic/Kconfig
+++ b/drivers/power/pmic/Kconfig
@@ -351,6 +351,17 @@
 	DC-DC converter, 8 LDOs and a RTC. This driver binds the SMPS and LDO
 	pmic children.
 
+config DM_PMIC_TPS80031
+	bool "Enable driver for Texas Instruments TPS80031/TPS80032 PMIC"
+	---help---
+	This config enables implementation of driver-model pmic uclass features
+	for TPS80031/TPS80032 PMICs. The driver implements read/write operations.
+	This is a Power Management IC with a decent set of peripherals from which
+	5 Buck Converters refered as Switched-mode power supply (SMPS), 11 General-
+	Purpose Low-Dropout Voltage Regulators (LDO), USB OTG Module, Real-Time
+	Clock (RTC) with Timer and Alarm Wake-Up, Two Digital PWM Outputs and more
+	with I2C Compatible Interface. PMIC occupies 4 I2C addresses.
+
 config PMIC_STPMIC1
 	bool "Enable support for STMicroelectronics STPMIC1 PMIC"
 	depends on DM_I2C