Re: [PATCH 4/6] arm: mach-omap2: remove "OMAP_DEVICE_NO_IDLE_ON_SUSPEND"check

[Sourav Poddar]

Hi Kevin,
On Friday 19 April 2013 08:22 PM, Kevin Hilman wrote:
> Sourav Poddar<sourav.poddar@xxxxxx>  writes:
>
> [...]
>
> > Yes, got your point. omap_device_idle should not be called only
> > for console uart.
> >
> > Just did a quick testing by including the following hunk on top of my
> > patch series..
> >
> > diff --git a/arch/arm/mach-omap2/omap_device.c
> > b/arch/arm/mach-omap2/omap_device.c
> > index c226946..7480e87 100644
> > --- a/arch/arm/mach-omap2/omap_device.c
> > +++ b/arch/arm/mach-omap2/omap_device.c
> > @@ -617,8 +617,10 @@ static int _od_suspend_noirq(struct device *dev)
> >          ret = pm_generic_suspend_noirq(dev);
> >
> >          if (!ret&&  !pm_runtime_status_suspended(dev)) {
> > -               if (pm_generic_runtime_suspend(dev) == 0)
> > +               if (pm_generic_runtime_suspend(dev) == 0) {
> > +                       omap_device_idle(pdev);
> >                          od->flags |= OMAP_DEVICE_SUSPENDED;
> > +               }
> >          }
> >
> >          return ret;
> > @@ -631,6 +633,7 @@ static int _od_resume_noirq(struct device *dev)
> >
> >          if ((od->flags&  OMAP_DEVICE_SUSPENDED)&&
> >              !pm_runtime_status_suspended(dev)) {
> > +               omap_device_enable(pdev);
> >                  od->flags&= ~OMAP_DEVICE_SUSPENDED;
> >                  pm_generic_runtime_resume(dev);
> >          }
> > And found the wakeup from UART is no more functional.
> > So, the omap_device_idle gets called for console UART also, thereby
> > preventing the "no_idle_on_suspend" theory.
> >
> > Hence, merely putting prepare/complete callback the way I did is not
> > helping.
> > We need to delete omap_device_idle also, which I agree is not correct.
> > So, we need a way to bypass this "omap_device_idle"
> > call for console UART. ?
> OK, I see what's happening now.
>
> How about this: rather than using prepare/complete callbacks, can you
> use the runtime_suspend callback to return an error code during suspend?
Yes, that can be done.
> (only for the console, and only when no_console_suspend is enabled, and
> only during suspend)
>
> Since _od_suspend_noirq checks to be sure the drivers ->runtime_suspend
> callback succeeds before it calls omap_device_idle(), if you report a
> failure, omap_device_idle will not be called.
True.

~Sourav
> Kevin

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