From: Stephan Gerhold <stephan@xxxxxxxxxxx> [ Upstream commit e27654df20d77ad7549a3cf6739ebaa3aa59a088 ] For some reason DB410c has completely bogus regulator constraints that actually just correspond to the programmable voltages which are already provided by the regulator driver. Some of them are not just outside the recommended operating conditions of the APQ8016E SoC but even exceed the absolute maximum ratings, potentially risking permanent device damage. In practice it's not quite as dangerous thanks to the RPM firmware: It turns out that it has its own voltage constraints and silently clamps all regulator requests. For example, requesting 3.3V for L5 (allowed by the current regulator constraints!) still results in 1.8V being programmed in the actual regulator hardware. Experimentation with various voltages shows that the internal RPM voltage constraints roughly correspond to the safe "specified range" in the PM8916 Device Specification (rather than the "programmable range" used inside apq8016-sbc.dtsi right now). Combine those together with some fixed voltages used in the old msm-3.10 device tree from Qualcomm to give DB410c some actually valid voltage constraints. Cc: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx> Fixes: 4c7d53d16d77 ("arm64: dts: apq8016-sbc: add regulators support") Signed-off-by: Stephan Gerhold <stephan@xxxxxxxxxxx> Signed-off-by: Bjorn Andersson <andersson@xxxxxxxxxx> Link: https://lore.kernel.org/r/20230510-msm8916-regulators-v1-1-54d4960a05fc@xxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/arm64/boot/dts/qcom/apq8016-sbc.dts | 64 ++++++++++++------------ 1 file changed, 32 insertions(+), 32 deletions(-) diff --git a/arch/arm64/boot/dts/qcom/apq8016-sbc.dts b/arch/arm64/boot/dts/qcom/apq8016-sbc.dts index 59860a2223b83..14cb217a13c1e 100644 --- a/arch/arm64/boot/dts/qcom/apq8016-sbc.dts +++ b/arch/arm64/boot/dts/qcom/apq8016-sbc.dts @@ -447,21 +447,21 @@ &smd_rpm_regulators { vdd_l7-supply = <&pm8916_s4>; s3 { - regulator-min-microvolt = <375000>; - regulator-max-microvolt = <1562000>; + regulator-min-microvolt = <1250000>; + regulator-max-microvolt = <1350000>; }; s4 { - regulator-min-microvolt = <1800000>; - regulator-max-microvolt = <1800000>; + regulator-min-microvolt = <1850000>; + regulator-max-microvolt = <2150000>; regulator-always-on; regulator-boot-on; }; l1 { - regulator-min-microvolt = <375000>; - regulator-max-microvolt = <1525000>; + regulator-min-microvolt = <1225000>; + regulator-max-microvolt = <1225000>; }; l2 { @@ -470,13 +470,13 @@ l2 { }; l4 { - regulator-min-microvolt = <1750000>; - regulator-max-microvolt = <3337000>; + regulator-min-microvolt = <2050000>; + regulator-max-microvolt = <2050000>; }; l5 { - regulator-min-microvolt = <1750000>; - regulator-max-microvolt = <3337000>; + regulator-min-microvolt = <1800000>; + regulator-max-microvolt = <1800000>; }; l6 { @@ -485,45 +485,45 @@ l6 { }; l7 { - regulator-min-microvolt = <1750000>; - regulator-max-microvolt = <3337000>; + regulator-min-microvolt = <1800000>; + regulator-max-microvolt = <1800000>; }; l8 { - regulator-min-microvolt = <1750000>; - regulator-max-microvolt = <3337000>; + regulator-min-microvolt = <2900000>; + regulator-max-microvolt = <2900000>; }; l9 { - regulator-min-microvolt = <1750000>; - regulator-max-microvolt = <3337000>; + regulator-min-microvolt = <3300000>; + regulator-max-microvolt = <3300000>; }; l10 { - regulator-min-microvolt = <1750000>; - regulator-max-microvolt = <3337000>; + regulator-min-microvolt = <2800000>; + regulator-max-microvolt = <2800000>; }; l11 { - regulator-min-microvolt = <1750000>; - regulator-max-microvolt = <3337000>; + regulator-min-microvolt = <2950000>; + regulator-max-microvolt = <2950000>; regulator-allow-set-load; regulator-system-load = <200000>; }; l12 { - regulator-min-microvolt = <1750000>; - regulator-max-microvolt = <3337000>; + regulator-min-microvolt = <1800000>; + regulator-max-microvolt = <2950000>; }; l13 { - regulator-min-microvolt = <1750000>; - regulator-max-microvolt = <3337000>; + regulator-min-microvolt = <3075000>; + regulator-max-microvolt = <3075000>; }; l14 { - regulator-min-microvolt = <1750000>; - regulator-max-microvolt = <3337000>; + regulator-min-microvolt = <1800000>; + regulator-max-microvolt = <3300000>; }; /** @@ -531,14 +531,14 @@ l14 { * for mezzanine boards */ l15 { - regulator-min-microvolt = <1750000>; - regulator-max-microvolt = <3337000>; + regulator-min-microvolt = <1800000>; + regulator-max-microvolt = <1800000>; regulator-always-on; }; l16 { - regulator-min-microvolt = <1750000>; - regulator-max-microvolt = <3337000>; + regulator-min-microvolt = <1800000>; + regulator-max-microvolt = <3300000>; }; l17 { @@ -547,8 +547,8 @@ l17 { }; l18 { - regulator-min-microvolt = <1750000>; - regulator-max-microvolt = <3337000>; + regulator-min-microvolt = <2700000>; + regulator-max-microvolt = <2700000>; }; }; -- 2.39.2