On Tue, Sep 25, 2012 at 09:30:29AM +0100, Russell King - ARM Linux wrote: > On Tue, Sep 25, 2012 at 01:52:03PM +0530, Poddar, Sourav wrote: > > Hi Greg, > > > > Ping on this? > > > > On Tue, Sep 18, 2012 at 6:10 PM, Sourav Poddar <sourav.poddar@xxxxxx> wrote: > > > Greg's tty-next is not booting on 2420 based N800. The failure is > > > observed at serial init itself. The reason might be that n800 tries to > > > resume even though it is not suspended before. > > How is this happening? I think that needs proper investigation - or if > it's had more investigation, then the results needs to be included in > the commit description so that everyone can understand the issue here. > > We should not be resuming a device which hasn't been suspended. Maybe > the runtime PM enable sequence is wrong, and that's what should be fixed > instead? > > This sequence in the probe() function: > > pm_runtime_irq_safe(&pdev->dev); > pm_runtime_enable(&pdev->dev); > pm_runtime_get_sync(&pdev->dev); > > would enable runtime PM while the s/w state indicates that it's disabled, > and then that pm_runtime_get_sync() will want to resume the device. See > the section "5. Runtime PM Initialization, Device Probing and Removal" > in Documentation/power/runtime_pm.txt, specifically the second paragraph > of that section. that was tested. It worked in pandaboard but didn't work on beagleboard XM. Sourav tried to start a discussion about that, but it simply died... In any case, pm_runtime_get_sync() in probe will always call runtime_resume callback, right ? -- balbi
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