Re: [PATCH] regulator: qcom-rpmh: Fix pm8010 pmic5_pldo502ln minimum voltage

From: Bryan O'Donoghue
Date: Wed Feb 21 2024 - 05:03:57 EST


On 21/02/2024 9:11 a.m., Fenglin Wu wrote:

So, programming it to either 1.8V or 1.808V, the HW will output 1.8V. I understand there is a problem for x1e801000 because its AOP side limits the voltage range to [1.808V, 1.808V] for LDO3/4/6 power rails, it won't work if linux side updates to use 1.8V. Actually the same issue applies to SM8550 and SM8650 if you simply update the voltage level to 1.808V, because their AOP side limits the voltage ranges for some of these LDOs to [1.8V, 1.8V].

Hmm.

We have no use case for 1.808 to my knowledge - the sensors take voltages in the range 1.7 to 1.9 volts.

TBH I think it should work just fine at 1.8v bang on.

I'll test this theory on the reference hardware and repost either a patch or further discussion.

But I think we should probably just leave what you've upstreamed and request 1.8 v in the dts honestly.

Thanks

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bod