Black Display after suspend/resume on Thinkpad X201 with 8.1/amd64

[geoffrey.ferrari]

Dear all,

I'm running FreeBSD 8.1/amd64 on a Thinkpad X201 (Intel Core i5 CPU with Intel integrated graphics). Everything works great except that there is a problem with the display when resuming after suspend. I was wondering if someone could offer some advice on whether it would be possible to get this working, and if I could help by providing any relevant information. The hardware on this machine is pretty new, but it would be great to get it working :-) I started discussing this a while back on the freebsd-mobile mailing list, but couldn't find a workable solution. The original discussion is here http://lists.freebsd.org/pipermail/freebsd-mobile/2010-May/011990.html .

The current situation is that the machine will suspend using acpiconf -s 3 and it will also resume. The problem is that the LCD display does not resume correctly after suspend - instead it just stays black. I've been randomly tweaking various things, and get slightly different results. Sometimes the display stays black in the sense the display is still completely switched off. Othertimes, I think the display switches on, but nothing is displayed, so that the display is on but showing nothing except a black background. However, I can still type blind and e.g. shutdown/restart the machine.

 It may help to know that suspend/resume works perfectly under the latest Ubuntu 10.04, without any special configuration. I've also updated this machine to the latest BIOS from Lenovo. I've made available a file containing the output or contents of /boot/loader.conf, /etc/rc.conf, dmesg, devinfo -vr, acpidump -td, and sysctl -a. This file can be downloaded from https://files.me.com/geoffrey.ferrari/oqv857 . I hope somebody will be able to help! At this stage, I'd be very grateful for any suggestions either on how to fix the problem myself, or on how to provide the right information to this list to help others to fix it. Right now, it's only suspend/resume that's keeping me from using FreeBSD as my work OS on a daily basis.

Incidentally, does anyone know if 9-CURRENT would support my Thinkpad better than 8.1?

Thanks,

Geoff