Re: UART misbehaves under Linkstation/KuroBoxHG

[Guennadi Liakhovetski <g.liakhovetski@gmx.de>]

On Wed, 8 Aug 2007, Oncaphillis wrote:

>  So that's ok ? No misconfiguration ? And that setserial tells
>  me the port is 0x000 ?

Yes, everything looks ok, don't know why, setserial reports 0 here too, 
but it doesn't cause me any (visible) problems.

>  I thought the dts file which
>  comes with the linkstation kernel describes the ports and IRQs
>  but poking there didn't change anything. It seems like the kernel
>  is ignoring the serial settings in the dts-file (which I do not
>  realy understand) all together.

Believe me, it doesn't ignore them:-) Don't know what exactly you were 
poking at there, but it should be quite easy to break it by changing 
clocks / address / irq...

>   I started with a debian distro
>   http://www.kurobox.com/mwiki/index.php/Debian_sylver
> 
>   Hmm I tried my very best to eliminate this everywhere. Actually I
>   resurrected the ARV00 device by creating a soft link to a ttySx
>   with during bootup within the udev filesystem.
> 
>   <snip>
>         if [ ! -e /dev/AVR00 ];then
>          cat /proc/tty/driver/serial | grep 80004500 | grep -q 0:
>            && AVR=/dev/ttyS0 || AVR=/dev/ttyS1
>          echo "Making AVR00 link to "$AVR;
>          ln -s $AVR /dev/AVR00
>         fi;
>   </snip>
> 
> Stole the trick from the avr_evtd startup script...

Well, just do "ls -l /dev/AVR00", then "lsof /dev/ttyS0".

In principle, as mentioned elsewhere before, you don't need any daemons on 
linkstation/kurobox now for "basic" operation, i.e., the kernel disables 
the watchdog on startup, and properly sends reboot and power-off commands 
to the AVR itself without any userspace support. So, at least for a test, 
you could stop all those daemons. You need them though if you want to use 
the buttons to power down / reboot / whatever, do other fancy things with 
the AVR...

Another possible reason why, for example, your stty misbehaves, maybe it 
is somehow broken in that distro? I am just using etch and things work 
pretty well.

Thanks
Guennadi
---
Guennadi Liakhovetski
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