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Date: Tue, 7 May 2024 13:43:13 +0200
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Subject: Re: [PATCH] phy: qcom-snps-femto-v2: Add load and voltage setting for
 LDO's used
To: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
 Udipto Goswami <quic_ugoswami@quicinc.com>
Cc: Bjorn Andersson <andersson@kernel.org>, Vinod Koul <vkoul@kernel.org>,
 Kishon Vijay Abraham I <kishon@kernel.org>, linux-arm-msm@vger.kernel.org,
 linux-phy@lists.infradead.org, linux-kernel@vger.kernel.org
References: <20240502123312.31083-1-quic_ugoswami@quicinc.com>
 <CAA8EJppeQTadmny=hcs4xCQDXHwXEBHXjeecvZCUVcSXmwBTgg@mail.gmail.com>
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From: Konrad Dybcio <konrad.dybcio@linaro.org>
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On 5/2/24 15:12, Dmitry Baryshkov wrote:
> On Thu, 2 May 2024 at 15:33, Udipto Goswami <quic_ugoswami@quicinc.com> wrote:
>>
>> The Femto phy depends on 0.88/ 1.8/ 3.3V regulators for its operation.
>> If one of the regulators is not voted to the required minimum voltage
>> for phy to operate, then High speed mode of operation will fail.
>>
>> On certain targets like (qcm6490_rb3gen2) where the minimum voltage
>> of the regulator is lower than the operating voltage of the phy.
>> If not voted properly, the phy supply would be limited to the min value
>> of the LDO thereby rendering the phy non-operational.
>>
>> The current implementation of the regulators in the Femto PHY is not
>> setting the load and voltage for each LDO. The appropriate voltages and
>> loads required for the PHY to operate should be set.
> 
> Please move min/max voltages to the DTS. There is no need to set them
> from the driver.
> 
> Also, is there any reason why you can't use `regulator-initial-mode =
> <RPMH_REGULATOR_MODE_HPM>;` like other boards do?

The point is to aggregate the values and switch to HPM if a threshold is
crossed (or stay in LPM otherwise)

Konrad