Bug#608616: Mobility Radeon HD 4200: Black screen after resuming from suspend / no-hibernation

[Margarita Manterola <marga@debian.org>]

Hola Sven Joachim!

> The difference is that the preinst of the Ubuntu package removes the
> file /etc/modprobe.d/radeon-kms.conf (it is not needed on Ubuntu,
> because Ubuntu kernels are built with KMS enabled), leaving you with UMS
> even after you reinstall the Debian package.

As I already stated in the bug report, the kms file is NOT missing.  I'm
not exactly sure why, but it didn't get removed.

Contents of /etc/modprobe.d/radeon-kms.conf:

options radeon modeset=1

> The first thing I would do is to test a newer kernel, e.g. 2.6.37-c7
> from experimental, and restore the missing file.

I forgot to include this in the report, sorry. I have already tried with
the kernel and X from experimental, no different outcome.

Only after trying both from experimental did I switch to trying Ubuntu's.

Also, once I installed the X driver from Ubuntu, all 3 kernels (Maverick's,
Squeeze's and Experimental's suspended and hibernated correctly), so it
looks like it's not a kernel problem, it's an X problem.

So, newer kernel doesn't help, the kms file is not missing.  Why could
Ubuntu's driver be making suspend work?

-- 
Love,
Marga