[PATCHv9 1/3] Runtime Interpreted Power Sequences
From: Tomi Valkeinen <hidden>
Date: 2012-11-21 08:49:12
Also in:
linux-devicetree, linux-fbdev, linux-pm, linux-tegra, lkml
From: Tomi Valkeinen <hidden>
Date: 2012-11-21 08:49:12
Also in:
linux-devicetree, linux-fbdev, linux-pm, linux-tegra, lkml
On 2012-11-21 10:32, Alex Courbot wrote:
quoted
Ok. I'll need to dig up the conversationIIRC it was somewhere around here: https://lkml.org/lkml/2012/9/7/662 See the parent messages too.
Thanks.
quoted
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 -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 897 bytes Desc: OpenPGP digital signature URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20121121/80b35acd/attachment.sig>