Occasional fail to initiate resume by incoming call, easy workaround proposed

Dieter Spaar spaar at openmoko.org
Wed Feb 11 13:15:07 CET 2009

Hello Werner,

Werner Almesberger wrote:
> Dieter Spaar wrote:
>> IO1 is low when the Calypso start up, so setting it again to low will  
>> not solve the problem.
> Hmm, when I
> echo 1 >/sys/bus/platform/devices/neo1973-pm-gsm.0/power_on
> I see a
> [149793.910000] modem wakeup interrupt
> in dmesg and GPF1 does read high afterwards. So this seems to be
> consistent with Paul's observations.

I am currently playing around with it. And it is again different than it 
the first time and second time ;-)

IO1 is low on reset of the calypso, however someone else has switched it
to high. Its not the fault of the UART driver, it seems to work fine. The
function which sets IO1 to high is the GPIO initialization in armio.c, the
comment for doing so is:

"On D-Sample GPIO 1 must be set to high to enable the audio amplifier."

Cool, this seems to be for necessary for the Calypso Evaluation board which
does really have an amplifier connected to IO1. But for our case, it 
just causes

I have removed setting IO1 to high at this place and so far it looks 
like it is
working as expected now.

Best regards,

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