This is a note to let you know that I've just added the patch titled arm64: dts: qcom: apq8016-sbc: Fix regulator constraints to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: arm64-dts-qcom-apq8016-sbc-fix-regulator-constraints.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit acb99861cdc5e77dcef8355419d022d031e555c8 Author: Stephan Gerhold <stephan@xxxxxxxxxxx> Date: Wed May 17 20:48:40 2023 +0200 arm64: dts: qcom: apq8016-sbc: Fix regulator constraints [ 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> diff --git a/arch/arm64/boot/dts/qcom/apq8016-sbc.dts b/arch/arm64/boot/dts/qcom/apq8016-sbc.dts index 1b613098fb4a0..c6f4ee7b82042 100644 --- a/arch/arm64/boot/dts/qcom/apq8016-sbc.dts +++ b/arch/arm64/boot/dts/qcom/apq8016-sbc.dts @@ -448,21 +448,21 @@ &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 { @@ -471,13 +471,13 @@ 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 { @@ -486,45 +486,45 @@ 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>; }; /** @@ -532,14 +532,14 @@ 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 { @@ -548,8 +548,8 @@ l17 { }; l18 { - regulator-min-microvolt = <1750000>; - regulator-max-microvolt = <3337000>; + regulator-min-microvolt = <2700000>; + regulator-max-microvolt = <2700000>; }; };