regulator: MAX8997/8966 support

This patch supports PMIC/Regulator part of MAX8997/MAX8966 MFD.
In this initial release, selecting voltages or current-limit
and switching on/off the regulators are supported.

Controlling voltages for DVS with GPIOs is not implemented fully
and requires more considerations: it controls multiple bucks (selection
of 1, 2, and 5) at the same time with SET1~3 gpios. Thus, when DVS-GPIO
is activated, we lose the ability to control the voltage of a single
buck regulator independently; i.e., contolling a buck affects other two
bucks. Therefore, using the conventional regulator framework directly
might be problematic. However, in this driver, we try to choose
a setting without such side effect of affecting other regulators and
then try to choose a setting with the minimum side effect (the sum of
voltage changes in other regulators).

On the other hand, controlling all the three bucks simultenously based
on the voltage set table may help build cpufreq and similar system
more robust; i.e., all the three voltages are consistent every time
without glitches during transition.

Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index e1d943619ab8..395d35941b84 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -108,6 +108,15 @@ config REGULATOR_MAX8952
           via I2C bus. Maxim 8952 has one voltage output and supports 4 DVS
           modes ranging from 0.77V to 1.40V by 0.01V steps.
 
+config REGULATOR_MAX8997
+        tristate "Maxim 8997/8966 regulator"
+        depends on MFD_MAX8997
+        help
+          This driver controls a Maxim 8997/8966 regulator
+          via I2C bus. The provided regulator is suitable for S5PC110,
+          S5PV210, and Exynos-4 chips to control VCC_CORE and
+          VCC_USIM voltages.
+
 config REGULATOR_MAX8998
         tristate "Maxim 8998 voltage regulator"
         depends on MFD_MAX8998