Regulator: LP3972 PMIC regulator driver

This patch adds regulator drivers for National Semiconductors LP3972 PMIC.
This LP3972 PMIC controller has 3 DC/DC voltage converters and 5 low drop-out
(LDO) regulators. LP3972 PMIC controller uses I2C interface.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 4889caa..dd30e88 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -172,6 +172,13 @@
 	 Say Y here to support the voltage regulators and convertors
 	 on National Semiconductors LP3971 PMIC
 
+config REGULATOR_LP3972
+	tristate "National Semiconductors LP3972 PMIC regulator driver"
+	depends on I2C
+	help
+	 Say Y here to support the voltage regulators and convertors
+	 on National Semiconductors LP3972 PMIC
+
 config REGULATOR_PCAP
 	tristate "PCAP2 regulator driver"
 	depends on EZX_PCAP