PM regression with LED changes in next-20161109

Tony Lindgren tony at atomide.com
Thu Nov 10 09:55:37 PST 2016


* Pavel Machek <pavel at ucw.cz> [161110 09:29]:
> Hi!
> 
> > >>>Looks like commit 883d32ce3385 ("leds: core: Add support for poll()ing
> > >>>the sysfs brightness attr for changes.") breaks runtime PM for me.
> > >>>
> > >>>On my omap dm3730 based test system, idle power consumption is over 70
> > >>>times higher now with this patch! It goes from about 6mW for the core
> > >>>system to over 440mW during idle meaning there's some busy timer now
> > >>>active.
> > >>>
> > >>>Reverting this patch fixes the issue. Any ideas?
> 
> Are you using any LED that toggles with high frequency? Like perhaps
> LED that is lit when CPU is active?

Yeah one of them seems to have cpu0 as the default trigger.

Tony



More information about the linux-arm-kernel mailing list