PDA Suspend SA1100

PDA Suspend SA1100

[Kristoffer Ericson]

Greetings,

I've been trying to implement proper suspend on my jornada 720 machine. But as far as I can see it never reaches
the sa11x0_suspend code.

I've linked power button event to produce APM_SUSPEND and I can see that it says "Stopping TASKS ======". It then
blanks screen but keeps LCD powerd. I know it goes into resume again since removing backlight code in resume function
effectivly turns off the LCD.

Im assuming that it tries to suspend but fails at some point and tries to return into normal operations?
Exactly what is needed to get the suspend procedure happy? Does every driver need to have suspend/resume code?

Best wishes
Kristoffer Ericson

Re: PDA Suspend SA1100

[eric miao]

On 10/19/07, Kristoffer Ericson <kristoffer.ericson@gmail.com> wrote:
> Greetings,
>
> I've been trying to implement proper suspend on my jornada 720 machine. But as far as I can see it never reaches
> the sa11x0_suspend code.
>
> I've linked power button event to produce APM_SUSPEND and I can see that it says "Stopping TASKS ======". It then
> blanks screen but keeps LCD powerd. I know it goes into resume again since removing backlight code in resume function
> effectivly turns off the LCD.
>
> Im assuming that it tries to suspend but fails at some point and tries to return into normal operations?
> Exactly what is needed to get the suspend procedure happy? Does every driver need to have suspend/resume code?

I don't think so. Unless a driver feels it necessary to take some
action, no suspend/resume
will not cause the whole system to fail. However,

1) if any driver suspend code returns error, the whole procedure will stop
2) and instable wake-up source (like glitch on wake-up GPIO pin) or
incorrect setting (like
wake up from RTC but set the interval to be 0) will also cause the
immediate resume

check "sa11x0_suspend" print out won't work since the console has already been
suspended, try DISABLE_CONSOLE_SUSPEND or other ways

- eric

>
> Best wishes
> Kristoffer Ericson
> -
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Re: PDA Suspend SA1100

[Kristoffer Ericson]

On Fri, 19 Oct 2007 08:56:18 +0800
"eric miao" <eric.y.miao@gmail.com> wrote:

> On 10/19/07, Kristoffer Ericson <kristoffer.ericson@gmail.com> wrote:
> > Greetings,
> >
> > I've been trying to implement proper suspend on my jornada 720 machine. But as far as I can see it never reaches
> > the sa11x0_suspend code.
> >
> > I've linked power button event to produce APM_SUSPEND and I can see that it says "Stopping TASKS ======". It then
> > blanks screen but keeps LCD powerd. I know it goes into resume again since removing backlight code in resume function
> > effectivly turns off the LCD.
> >
> > Im assuming that it tries to suspend but fails at some point and tries to return into normal operations?
> > Exactly what is needed to get the suspend procedure happy? Does every driver need to have suspend/resume code?
> 
> I don't think so. Unless a driver feels it necessary to take some
> action, no suspend/resume
> will not cause the whole system to fail. However,
Ah, good to know.

> 
> 1) if any driver suspend code returns error, the whole procedure will stop
> 2) and instable wake-up source (like glitch on wake-up GPIO pin) or
> incorrect setting (like
> wake up from RTC but set the interval to be 0) will also cause the
> immediate resume
I'll start running through the different drivers to see if I can spot anything obvious.
> 
> check "sa11x0_suspend" print out won't work since the console has already been
> suspended, try DISABLE_CONSOLE_SUSPEND or other ways
> 
> - eric
> 
> >
> > Best wishes
> > Kristoffer Ericson
> > -
> > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> > Please read the FAQ at  http://www.tux.org/lkml/
> >


-- 
Kristoffer Ericson <Kristoffer.Ericson@Gmail.com>