GTA02: fix for clicking noise and JACK_INSERT interrupts

Werner Almesberger werner at
Tue Feb 26 13:07:36 CET 2008

Driving nDL_GSM low caused the GSM modem to inject communication requests
into the audio system, causing the characteristical clicking sound of a
GTA02 starting up, and these requests also caused lots of interrupts on
JACK_INSERT, slowing down the CPU.

I've checked in a fix to u-boot in revision 4118 that sets nDL_GSM high
by default, and lowers it only when we turn the modem on or off. (Under
Linux, nDL can be controlled separately with

- Werner

----------------------------------- Changes -----------------------------------

- board/neo1973/gta02/gta02.c (neo1973_gsm): make "neo1973 gsm on" also turn 
  off the nDL_GSM line (thus enabling downloads), and "neo1973 gsm off" turn
  it on again (thus avoiding all the nasty side-effects)
- board/neo1973/gta02/gta02.c (board_init): turn GPJ6/nDL_GSM on by default
  (thus enabling downloads and getting rid of all the weird effects caused by
gta02-splash.patch: refreshed for above change

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