linux-kernel - Re: [PATCH v2] arm64: dts: qcom: sm8550: Correct the min/max voltages for vreg_l6n

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <aabcf5d1-7380-40c8-896f-6ce37944e97d@oss.qualcomm.com>
Date: Mon, 23 Jun 2025 13:23:21 +0200
From: Konrad Dybcio <konrad.dybcio@....qualcomm.com>
To: Kamal Wadhwa <kamal.wadhwa@....qualcomm.com>,
        Bjorn Andersson <andersson@...nel.org>,
        Konrad Dybcio <konradybcio@...nel.org>, Rob Herring <robh@...nel.org>,
        Krzysztof Kozlowski <krzk+dt@...nel.org>,
        Conor Dooley <conor+dt@...nel.org>
Cc: linux-arm-msm@...r.kernel.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org,
        Neil Armstrong <neil.armstrong@...aro.org>
Subject: Re: [PATCH v2] arm64: dts: qcom: sm8550: Correct the min/max voltages
 for vreg_l6n_3p3

On 6/20/25 5:29 PM, Kamal Wadhwa wrote:
> Voltage regulator 'vreg_l6n_3p3' max-microvolt prop is currently
> configured at 3304000uV in different sm8550 board files. However this
> is not a valid voltage value for 'pmic5_pldo502ln' type voltage
> regulators.
> 
> Check below the max value(3200mV) in the regulator summary for min/max
> used as 2800mV/3304mV in DT:-
> 
> logs:
> 
> [    0.294781] vreg_l6n_3p3: Setting 2800000-3304000uV
> 
> regulator summary:
> 
> regulator     use open bypass  opmode   voltage current  min     max
> ---------------------------------------------------------------------
> ..
> vreg_l6n_3p3   0    0    0     normal   2800mV   0mA  2800mV  3200mV
> ..
> 
> Correct the min/max value to 3200000uV, as that is the closest valid
> value to 3.3V and Hardware team has also confirmed that its good to
> support the consumers(camera sensors) of this regulator.
> 
> Reviewed-by: Neil Armstrong <neil.armstrong@...aro.org>
> Signed-off-by: Kamal Wadhwa <kamal.wadhwa@....qualcomm.com>
> ---

FWIW it seems like 3.312v (which is slightly above the previous
value) is also supported:

static const struct rpmh_vreg_hw_data pmic5_pldo502ln = {
        .regulator_type = VRM,
        .ops = &rpmh_regulator_vrm_ops,
        .voltage_ranges = (struct linear_range[]) {
                REGULATOR_LINEAR_RANGE(1800000, 0,  2,  200000),
                REGULATOR_LINEAR_RANGE(2608000, 3,  28, 16000),
                REGULATOR_LINEAR_RANGE(3104000, 29, 30, 96000),
                REGULATOR_LINEAR_RANGE(3312000, 31, 31, 0),
        },
        .n_linear_ranges = 4,
        .n_voltages = 32,
        .pmic_mode_map = pmic_mode_map_pmic5_ldo_hpm,
        .of_map_mode = rpmh_regulator_pmic4_ldo_of_map_mode,
};

but if the hw folks say we can do with the lower value, it's probably
even better

Konrad