Messages in this thread | | | Date | Tue, 5 Jul 2011 10:22:09 -0400 (EDT) | From | Alan Stern <> | Subject | RE: [PATCH 6/6 v2] arm: omap: usb: global Suspend and resume support of ehci and ohci |
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On Tue, 5 Jul 2011, Partha Basak wrote:
> >> Note that the parent per-se does not have any .suspend & .resume > >hooked > >> up. > > > >Why not? That sounds like a big bug. > > This was a design decision since the parent needs to be activated only > when at-least one child is insmoded. > > If the chidren are suspended, automatically the parent is suspended > via the pm_runtime_putsync calls to the parent.
Now you know that this isn't true, because those calls don't get made while a system sleep transition is in progress.
> So, effectively, we do not need an explicit suspend for the parent.
Now you know that effectively you _do_ need an explicit suspend for the parent.
> >You have ignored a few very important points: > > > >Firstly, system suspend is supposed to work even when runtime PM is not > >configured. > > > >Secondly, the user can disable runtime PM via sysfs at any time. This > >shouldn't mess up system suspend. > > > >Basically, it's a bad idea to mix up system suspend with runtime PM. > > Your observations are correct but this is a generic limitation and Kevin > is working > on this problem in parallel. > > As of now, all OMAP drivers are mandated to use ONLY runtime pm framework > for enabling/disabling clocks. I will let Kevin comment further.
Okay, let's see what Kevin says.
Alan Stern
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