regulator: add driver for hi6421 voltage regulator

Add driver support for HiSilicon Hi6421 voltage regulators.

Two rules for regulator enabling are defined in hi6421 spec:
1) Between disable and enable of each regulator (LDOs or BUCKs), there must
   be a protection gap. Use @off_on_delay of regulator core to implement this.
2) No two regulators can be enabled at the same time. Use mutex in
   hi6421_regulator_pdata to ensure this. A protection gap of 100us is added
   into each LDO/BUCK's .enable_time.

Signed-off-by: Guodong Xu <guodong.xu@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 2dc8289e5dba..e6b98ed4c12f 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -240,6 +240,16 @@ config REGULATOR_GPIO
           and the platform has to provide a mapping of GPIO-states
           to target volts/amps.
 
+config REGULATOR_HI6421
+        tristate "HiSilicon Hi6421 PMIC voltage regulator support"
+        depends on MFD_HI6421_PMIC && OF
+        help
+          This driver provides support for the voltage regulators on the
+          HiSilicon Hi6421 PMU / Codec IC.
+          Hi6421 is a multi-function device which, on regulator part, provides
+          21 general purpose LDOs, 3 dedicated LDOs, and 5 BUCKs. All
+          of them come with support to either ECO (idle) or sleep mode.
+
 config REGULATOR_ISL6271A
         tristate "Intersil ISL6271A Power regulator"
         depends on I2C