[PATCH v2] regulator: max14577: Add set_mode/get_mode for MAX77836 LDOs

[Jad Keskes]

The MAX77836 LDOs support two operating modes via the PWRMD field in
CNFG1_LDO registers: normal and low-power (5 mA max load, reduced
quiescent current).  Implement the get_mode and set_mode callbacks
so consumers can switch between them.

The PWRMD field is the same register used for enable/disable and
controls the immediate operating mode, rather than a suspend-specific
behavior.  Use set_mode instead of the originally-requested
set_suspend_mode.

Remove the TODO comment that has been sitting here since the driver
was first added.

Signed-off-by: Jad Keskes <inasj268@xxxxxxxxx>
---
 drivers/regulator/max14577-regulator.c | 43 +++++++++++++++++++++++++-
 include/linux/mfd/max14577-private.h   |  3 ++
 2 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/drivers/regulator/max14577-regulator.c b/drivers/regulator/max14577-regulator.c
index 41fd15adfd1f..5c56a12dcefc 100644
--- a/drivers/regulator/max14577-regulator.c
+++ b/drivers/regulator/max14577-regulator.c
@@ -123,6 +123,46 @@ static const struct regulator_desc max14577_supported_regulators[] = {
 	[MAX14577_CHARGER] = MAX14577_CHARGER_REG,
 };
 
+static unsigned int max77836_ldo_get_mode(struct regulator_dev *rdev)
+{
+	unsigned int val;
+	int ret;
+
+	ret = regmap_read(rdev->regmap, rdev->desc->enable_reg, &val);
+	if (ret)
+		return ret;
+
+	val &= MAX77836_CNFG1_LDO_PWRMD_MASK;
+	switch (val) {
+	case MAX77836_CNFG1_LDO_PWRMD_LPM:
+		return REGULATOR_MODE_IDLE;
+	case MAX77836_CNFG1_LDO_PWRMD_NORMAL:
+		return REGULATOR_MODE_NORMAL;
+	default:
+		return REGULATOR_MODE_INVALID;
+	}
+}
+
+static int max77836_ldo_set_mode(struct regulator_dev *rdev,
+		unsigned int mode)
+{
+	unsigned int val;
+
+	switch (mode) {
+	case REGULATOR_MODE_NORMAL:
+		val = MAX77836_CNFG1_LDO_PWRMD_NORMAL;
+		break;
+	case REGULATOR_MODE_IDLE:
+		val = MAX77836_CNFG1_LDO_PWRMD_LPM;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
+		MAX77836_CNFG1_LDO_PWRMD_MASK, val);
+}
+
 static const struct regulator_ops max77836_ldo_ops = {
 	.is_enabled		= regulator_is_enabled_regmap,
 	.enable			= regulator_enable_regmap,
@@ -131,7 +171,8 @@ static const struct regulator_ops max77836_ldo_ops = {
 	.map_voltage		= regulator_map_voltage_linear,
 	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
 	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
-	/* TODO: add .set_suspend_mode */
+	.get_mode		= max77836_ldo_get_mode,
+	.set_mode		= max77836_ldo_set_mode,
 };
 
 #define MAX77836_LDO_REG(num)	{ \
diff --git a/include/linux/mfd/max14577-private.h b/include/linux/mfd/max14577-private.h
index dd51a37fa37f..5957e15b568e 100644
--- a/include/linux/mfd/max14577-private.h
+++ b/include/linux/mfd/max14577-private.h
@@ -350,6 +350,9 @@ enum max77836_pmic_reg {
 #define MAX77836_CNFG1_LDO_PWRMD_SHIFT		6
 #define MAX77836_CNFG1_LDO_TV_SHIFT		0
 #define MAX77836_CNFG1_LDO_PWRMD_MASK		(0x3 << MAX77836_CNFG1_LDO_PWRMD_SHIFT)
+#define MAX77836_CNFG1_LDO_PWRMD_OFF		(0x0 << MAX77836_CNFG1_LDO_PWRMD_SHIFT)
+#define MAX77836_CNFG1_LDO_PWRMD_LPM		(0x1 << MAX77836_CNFG1_LDO_PWRMD_SHIFT)
+#define MAX77836_CNFG1_LDO_PWRMD_NORMAL		(0x3 << MAX77836_CNFG1_LDO_PWRMD_SHIFT)
 #define MAX77836_CNFG1_LDO_TV_MASK		(0x3f << MAX77836_CNFG1_LDO_TV_SHIFT)
 
 /* LDO1/LDO2 CONFIG2 register */
-- 
2.54.0