Re: [PATCHv9 1/3] Runtime Interpreted Power Sequences

Tomi Valkeinen
2012-11-21T08:48:45Z

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On 2012-11-21 10:32, Alex Courbot wrote:

>> Ok. I'll need to dig up the conversation
>
> IIRC it was somewhere around here:
>
> https://lkml.org/lkml/2012/9/7/662
>
> See the parent messages too.

Thanks.

>> Did you consider any examples
>> of how some driver could handle the error cases?
>
> For all the (limited) use cases I considered, playing the power-off sequence
> when power-on fails just works. If power-off also fails you are potentially in
> more trouble though. Maybe we could have another "run" function that does not
> stop on errors for handling such cases where you want to "stop everything you
> can".

If the power-off sequence disables a regulator that was supposed to be
enabled by the power-on sequence (but wasn't enabled because of an
error), the regulator_disable is still called when the driver runs the
power-off sequence, isn't it? Regulator enables and disables are ref
counted, and the enables should match the disables.

> Failures might be better handled if sequences have some "recovery policy"
> about what to do when they fail, as mentioned in the link above. As you
> pointed out, the driver might not always know enough about the resources
> involved to do the right thing.

Yes, I think such recovery policy would be needed.

Tomi

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