[PATCH 5.4 12/72] regulator: pwm: Fix machine constraints application

From: Greg Kroah-Hartman
Date: Mon Sep 21 2020 - 12:48:36 EST


From: Vincent Whitchurch <vincent.whitchurch@xxxxxxxx>

[ Upstream commit 59ae97a7a9e1499c2070e29841d1c4be4ae2994a ]

If the zero duty cycle doesn't correspond to any voltage in the voltage
table, the PWM regulator returns an -EINVAL from get_voltage_sel() which
results in the core erroring out with a "failed to get the current
voltage" and ending up not applying the machine constraints.

Instead, return -ENOTRECOVERABLE which makes the core set the voltage
since it's at an unknown value.

For example, with this device tree:

fooregulator {
compatible = "pwm-regulator";
pwms = <&foopwm 0 100000>;
regulator-min-microvolt = <2250000>;
regulator-max-microvolt = <2250000>;
regulator-name = "fooregulator";
regulator-always-on;
regulator-boot-on;
voltage-table = <2250000 30>;
};

Before this patch:

fooregulator: failed to get the current voltage(-22)

After this patch:

fooregulator: Setting 2250000-2250000uV
fooregulator: 2250 mV

Signed-off-by: Vincent Whitchurch <vincent.whitchurch@xxxxxxxx>
Link: https://lore.kernel.org/r/20200902130952.24880-1-vincent.whitchurch@xxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/regulator/pwm-regulator.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c
index e74e11101fc15..0a9d61a91f436 100644
--- a/drivers/regulator/pwm-regulator.c
+++ b/drivers/regulator/pwm-regulator.c
@@ -279,7 +279,7 @@ static int pwm_regulator_init_table(struct platform_device *pdev,
return ret;
}

- drvdata->state = -EINVAL;
+ drvdata->state = -ENOTRECOVERABLE;
drvdata->duty_cycle_table = duty_cycle_table;
drvdata->desc.ops = &pwm_regulator_voltage_table_ops;
drvdata->desc.n_voltages = length / sizeof(*duty_cycle_table);
--
2.25.1