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, 27 insertions, 1 deletions

diff --git a/include/linux/mfd/max8997.h b/include/linux/mfd/max8997.h
index d0d9136c104b..cb671b3451bf 100644
--- a/include/linux/mfd/max8997.h
+++ b/include/linux/mfd/max8997.h
@@ -68,6 +68,8 @@ enum max8998_regulators {
         MAX8997_CHARGER_CV, /* control MBCCV of MBCCTRL3 */
         MAX8997_CHARGER, /* charger current, MBCCTRL4 */
         MAX8997_CHARGER_TOPOFF, /* MBCCTRL5 */
+
+        MAX8997_REG_MAX,
 };
 
 struct max8997_regulator_data {
@@ -77,7 +79,31 @@ struct max8997_regulator_data {
 
 struct max8997_platform_data {
         bool wakeup;
-        /* PMIC: Not implemented */
+        /* IRQ: Not implemented */
+        /* ---- PMIC ---- */
+        struct max8997_regulator_data *regulators;
+        int num_regulators;
+
+        /*
+         * SET1~3 DVS GPIOs control Buck1, 2, and 5 simultaneously. Therefore,
+         * With buckx_gpiodvs enabled, the buckx cannot be controlled
+         * independently. To control buckx (of 1, 2, and 5) independently,
+         * disable buckx_gpiodvs and control with BUCKxDVS1 register.
+         *
+         * When buckx_gpiodvs and bucky_gpiodvs are both enabled, set_voltage
+         * on buckx will change the voltage of bucky at the same time.
+         *
+         */
+        bool ignore_gpiodvs_side_effect;
+        int buck125_gpios[3]; /* GPIO of [0]SET1, [1]SET2, [2]SET3 */
+        int buck125_default_idx; /* Default value of SET1, 2, 3 */
+        unsigned int buck1_voltage[8]; /* buckx_voltage in uV */
+        bool buck1_gpiodvs;
+        unsigned int buck2_voltage[8];
+        bool buck2_gpiodvs;
+        unsigned int buck5_voltage[8];
+        bool buck5_gpiodvs;
+
         /* MUIC: Not implemented */
         /* HAPTIC: Not implemented */
         /* RTC: Not implemented */