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Date: Wed, 21 Feb 2024 09:58:23 +0000
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Subject: Re: [PATCH] regulator: qcom-rpmh: Fix pm8010 pmic5_pldo502ln minimum
 voltage
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To: Fenglin Wu <quic_fenglinw@quicinc.com>, Mark Brown <broonie@kernel.org>
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From: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
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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

---
bod