Re: [PATCH V2 1/1] soc: qcom: smp2p: Add wakeup capability to SMP2P IRQ

From: Stephen Boyd
Date: Mon Sep 13 2021 - 15:42:34 EST


Quoting Deepak Kumar Singh (2021-09-13 10:45:19)
>
> On 8/17/2021 1:53 AM, Stephen Boyd wrote:
> >> + ret = device_init_wakeup(&pdev->dev, true);
> > I still wonder if it's better to leave this off by default and only
> > enable it if the kernel is using autosuspend (PM_AUTOSLEEP). Then
> > userspace is responsible to decide if it can handle the wakeup with the
> > screen off, reload the remoteproc, and go back to suspend if it isn't
> > using autosuspend.
>
> Seems like not all targets use PM_AUTOSLEEP feature, even those targets
> may require wakeup to handle
>
> modem crash so that important modem events are not missed. I think we
> can keep wake up as default behavior
>
> and let the user space disable it through sysfs if it doesn't want it as
> wake up source.

I don't understand. What if userspace is simple and doesn't use
autosleep and will turn the screen on when the kernel resumes? Why do we
expect the modem crashing and causing the screen to turn on to be a good
user experience?