2021-03-02 17:41:43

by Uwe Kleine-König

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Subject: Re: [PATCH v5 4/7] pwm: pca9685: Reset registers to POR state in probe

Hello Clemens,

On Tue, Dec 15, 2020 at 10:22:25PM +0100, Clemens Gruber wrote:
> Reset the prescale and ON/OFF registers to their POR default state in
> the probe function. Otherwise, the PWMs could still be active after a
> watchdog reset and reboot, etc.

My memories are swapped out because it's already so long ago I looked
into this series. I thought it was already said that taking over the
configured state in probe is the nice thing to do?!

Best regards
Uwe

--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | https://www.pengutronix.de/ |


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2021-03-04 17:27:54

by Clemens Gruber

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Subject: Re: [PATCH v5 4/7] pwm: pca9685: Reset registers to POR state in probe

On Mon, Mar 01, 2021 at 10:46:33PM +0100, Uwe Kleine-K?nig wrote:
> Hello Clemens,
>
> On Tue, Dec 15, 2020 at 10:22:25PM +0100, Clemens Gruber wrote:
> > Reset the prescale and ON/OFF registers to their POR default state in
> > the probe function. Otherwise, the PWMs could still be active after a
> > watchdog reset and reboot, etc.
>
> My memories are swapped out because it's already so long ago I looked
> into this series. I thought it was already said that taking over the
> configured state in probe is the nice thing to do?!

Yes, but Sven voiced some concerns about the introduced complexities
when removing the resets.

I was torn between the two options.

I think it would be a good idea to first switch to the atomic API while
keeping the resets and then evaluate removing them in a separate patch
series.

Thanks,
Clemens