> -----Original Message----- > From: Alan Stern [mailto:stern@xxxxxxxxxxxxxxxxxxx] > Sent: Monday, January 31, 2011 8:43 PM > To: Rajendra Nayak > Cc: Kevin Hilman; Ben Dooks; linux-i2c@xxxxxxxxxxxxxxx; linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx; linux- > omap@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > Subject: Re: [PATCH] i2c: OMAP: fix static suspend vs. runtime suspend > > On Mon, 31 Jan 2011, Rajendra Nayak wrote: > > > Can you elaborate a bit more on how/why runtime PM transitions > > are disabled during system suspend, and how is it taken care > > of that a runtime resume of a device works however a subsequent > > runtime (re)suspend does not? > > I'll answer for Kevin. This is done by the PM core, in order to > prevent runtime power transitions from interfering with a system power > transition. The PM core increments the device's usage_count; this > prevents the device from being runtime-suspended but it allows > runtime-resume calls to go through. Thanks, I did remember seeing the pm_runtime_get_noresume() in dpm_prepare(). Just did not correlate it was the same Kevin was trying to say. Regards, Rajendra > > Alan Stern _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
