[ltp] APM suspend with 2.6 kernel [long]

[Michael Hagemann]

On Fri, 02 Jan 2004 21:26:49 -0500 Charles Lepple wrote:

> I have seen a number of posts from people who could successfully suspend their 
> ThinkPad under 2.4.x but could not with 2.6.x-test kernels. I don't have a 
> one-size-fits-all solution, but this email may help folks who are willing to 
> probe deeper into the problem. I did my debugging using Debian unstable on a 
> ThinkPad 770 (type 9548-30U).

I tried to reproduce this on a ThinkPad 600E (2645-4A0) but am still out of
luck.  This seems interesting, because some people seem to be able to
suspend a TP 600X.  What are the significant differences, anyway?

Here are the results of my search for the latest working kernel:

Version		Suspend working?

2.5.16		yes
2.5.24		yes
2.5.26		yes
2.5.27		yes (gcc-3.3.3)
2.5.28		no  (gcc-3.3.3)
2.5.28		no  (gcc-2.95.4)
2.5.30		no
2.5.31		no
2.6.1-rc1	no

The gcc version indicates that I tried a number of different options on this
and later kernels.

A first look at the ChangeLog and the patch shows a slightly different IRQ
handling in the i386/kernel and apm routines.  I will try to apply some of
the patches in order to isolate the bad guy...

It would be nice if other people with a TP 600/E/X could try to acknowledge
this behaviour.


michael