[alsa-devel] [PATCH 1/2] OMAP3: MCBSP: Suspend/resume failure fix

[Wang, Jane]

> > Also context save/restore operations belongs more to PM callbacks
> > of .../plat-omap/mcbsp.c. Or probably that can be done also dynamically
> > inside the omap_mcbsp_start/-stop for keeping the whole McBSP shutdown
> > whenever it is idle.
> [Aggarwal, Anuj] I am sorry I couldn't understand that. Did you mean that
> PM hooks can be added in the mcbsp driver which can be registered and
> called
> As and when required? Any reference driver for this, if my understanding
> is correct?
> >
> > I think it's worth to look McBSP register cache concept [1] from Janusz
> > Krzysztofik would it help all of this context save/restore operations.
> [Aggarwal, Anuj] I tried these two patches on omap3 evm but they didn't
> work for me. The system doesn't go to the suspend state when I do:
> echo mem > /sys/power/state
> And the culprits were core (think sdma) and per domain. I tried
> disabling the mcbsp i/f clock as well but it didn't help. On mcbsp
> register dump, I couldn't find the sysconfig register getting
> configured. Could that be the root cause?

Did you include this patch?
http://git.kernel.org/?p=linux/kernel/git/broonie/sound-2.6.git;a=commit;h=9da65a99e5e6a074c586474961dbf560e439df50

Without this patch, omap_stop_dma() did not disable DMA channel.


Regards,

-Jane