Question Compaq C-Series 810 serial ports.

[jscottkasten%yahoo.com@localhost]

In addition to my previous comments, I also noticed problems with the serial 
ports.  Any attempt at using /dev/ttyTX00 for wired serial resulted in a nasty 
kernel panic.  Using serial IR over /dev/ttyTX01 only sort of worked.

I again did more research in the list archives and found a patch by Uchiyama 
Yasushi for the C-Series 2010C that appears to fix some GPIO addressing 
affecting the first serial port.  I have since found that this patch was 
integrated in the mainstream for both 2010C and the 810, and is found in the 
4.0 release which I unfortunately am not able to run for other reasons yet.

I back ported this to my 2.1 kernel config and rebuilt.  The wired serial port 
is now partially functional.

I have no problems sending characters out TX00 and TX01 at any useful serial 
line rate.  However, I am finding that once in a while, an inbound character 
appears to cause a driver hang.  Sometimes it only hangs the process using the 
port, sometimes it hangs the entire kernel.  This problem happens often enough 
on inbound characters that one cannot seriously use the TX ports for data xfer.

I can't help but be suspicious of lost or masked interrupts in a situation like 
this.  Before I start digging deep, I am wondering if this is an issue that may 
have already been fixed, or if someone has already done some research on it?

Thanks in advance for any input people have to share.

Regards,

-S-