[PATCH] qi: initialize PMU GPIOs

Joerg Reisenweber joerg at openmoko.org
Sat Jan 24 15:04:14 CET 2009

Am Sa  24. Januar 2009 schrieb Joerg Reisenweber:
> Also to handle powerup in a sensible way, it seems to me sysfs driver should 
> use he following sequence:
> [2009-01-24 09:05:17] <DocScrutinizer> 
> apply power (via GSM_ON, U1705) and 
> assert modem-reset (to be found on gta01 only?). 
> Wait for reset to complete (mwait(xyz)). 
> deassert modem-reset. 
> wait again some 100ms. 
> assert MODEM_ON pushbutton of calypso (this is literally a power puhbutton 
> input). 
> wait for time needed by calypso to sense this button pressed and power up 
> (might well be some seconds). 
> deassert button aka MODEM_ON

Well I'm not quite sure about my suggestion for MODEM_RESET handling is 
exactly ok here. I seem to remember the calypso TESTRSTZ input isn't used as 
a simple powerup reset. Instead it triggers reset of bootloader (to start 
firmware flashing for example). That's why the driver transistor is NC in 
Could anybody with more historic background knowledge please have a look on 
this? :-)

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