[RFC 5/8] regulator: anatop: fix min dropout for bypass mode

From: Leonard Crestez
Date: Wed Mar 22 2017 - 13:09:13 EST


From: Irina Tirdea <irina.tirdea@xxxxxxx>

In bypass mode, the anatop digital regulators do not have any minimum
dropout value (the input voltage is equal to the output voltage according
to documentation).

Having a min dropout value of 125mV will lead to an increased voltage
for PMIC supplies.

Only set minimum dropout value for ldo enabled mode.

Signed-off-by: Irina Tirdea <irina.tirdea@xxxxxxx>
Signed-off-by: Leonard Crestez <leonard.crestez@xxxxxxx>
---
drivers/regulator/anatop-regulator.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/regulator/anatop-regulator.c b/drivers/regulator/anatop-regulator.c
index b041f27..64554e8 100644
--- a/drivers/regulator/anatop-regulator.c
+++ b/drivers/regulator/anatop-regulator.c
@@ -38,6 +38,8 @@
#define LDO_POWER_GATE 0x00
#define LDO_FET_FULL_ON 0x1f

+#define LDO_MIN_DROPOUT_UV 125000
+
struct anatop_regulator {
const char *name;
u32 control_reg;
@@ -153,6 +155,10 @@ static int anatop_regmap_set_bypass(struct regulator_dev *reg, bool enable)

sel = enable ? LDO_FET_FULL_ON : anatop_reg->sel;
anatop_reg->bypass = enable;
+ if (anatop_reg->bypass)
+ anatop_reg->rdesc.min_dropout_uV = 0;
+ else
+ anatop_reg->rdesc.min_dropout_uV = LDO_MIN_DROPOUT_UV;

return regulator_set_voltage_sel_regmap(reg, sel);
}
@@ -264,7 +270,7 @@ static int anatop_regulator_probe(struct platform_device *pdev)
rdesc->vsel_reg = sreg->control_reg;
rdesc->vsel_mask = ((1 << sreg->vol_bit_width) - 1) <<
sreg->vol_bit_shift;
- rdesc->min_dropout_uV = 125000;
+ rdesc->min_dropout_uV = LDO_MIN_DROPOUT_UV;

config.dev = &pdev->dev;
config.init_data = initdata;
@@ -286,6 +292,7 @@ static int anatop_regulator_probe(struct platform_device *pdev)
if (sreg->sel == LDO_FET_FULL_ON) {
sreg->sel = 0;
sreg->bypass = true;
+ rdesc->min_dropout_uV = 0;
}

/*
--
2.7.4