On 2/10/26 01:31, Martin Blumenstingl wrote:

Hi George,

sorry for the late reply.

On Thu, Jan 29, 2026 at 3:48 PM George Stark [off-list ref] wrote:

Hello Martin. It's great to hear from you again.

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On 1/26/26 12:35, Nick Xie wrote:

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Thanks for the patch. Since you have khadas mail I'm pretty sure you've
had the possibility to test it on the real vim board and I just don't
get it how it works with the voltage table above. The problem is that
pwm is calculated incorrectly in the upstream pwm-meson driver. That
voltage table appeared to be used in early amlogic bl loader and
appropriate pwm is initialized from a table's record. Duty cycle value
is translated to pwm regs correctly. Later when kernel start running
pwm-regulator driver is probed. It reads the pwm regs, calculates back
duty-cyle and search it in the table. Since calculation algos are not
match and the table doesn't contain full range of 0-100% values
regulator driver doesn't find current voltage. In such case regulator
core sets the minimum voltage from the table [1] and the SoC may hang
(depending on board) due to minimum voltage may be too low for the
current frequency SoC uses.

Nick likely didn't spot any issues on S4 since CPU frequency scaling
is not upstreamed yet (as there's no way to control the CPU clock
yet).
The lack of a OPP table means: the PWM and CPU clock will just stay at
whatever the bootloader provides

It makes sense. I should experiment on the latest kernel.

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Or I'm missing something?

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There's not-yet-reviewed patch that fixes pwm algo [2]. There's
calculation example in the cover letter.
[1] https://elixir.bootlin.com/linux/v6.19-rc5/source/drivers/regulator/core.c#L1227
[2] https://lkml.iu.edu/2412.3/00826.html

What's the status of such patches?

the patch is ready for review. It's seems like nobody is interested

I'm sorry to see that the patch had it's first anniversary.
I'll need to bring out my logic analyzer and test your patch (I hope
it's precise enough to show the impact of your changes).
Are your plans then to re-send the patches or have you moved on and
need someone else to take care of it?

It's a major step anyway if you confirm the issue yourself with an 
analyzer. In that case discussion won't be delayed for one more year
I think. Thanks.

Sure I'm ready to discuss/fix/resend this patch.

-- 
Best regards
George