Re: Suspend Mode

[Russell Coker <russell@coker.com.au>]

>This sounds very interesting to me, as I have a Dell Latitude CPi, and
>I've never managed to get suspend-to-disk working in Linux. Even normal
>suspend is a bit flaky. I have tried many 2.2 kernels with apm compiled 
>in, and I run apmd too. It suspends and writes data to disk, but when I
>resume, it freezes with a black screen and a blinking cursor in the top
>left corner.

I have a ThinkPad 380XD, suspend to disk has always worked perfectly for me (I
started with kernel ~2.1.90, I've used most kernels between then and
2.2.12/2.3.15 and never had a problem with this).  My sister has a ThinkPad
380XD purchased 6 weeks later than mine.  Her machine initially didn't work
with suspend to disk (crashed on resume), or even regular suspend.

Then the following feature appeared in the kernel:
Allow interrupts during APM BIOS calls

As soon as I installed a kernel on her machine with that support it all worked.

If that option is disabled then I recommend that you turn it on.  If not then I
recommend that you tell us all of your APM settings.  BTW Here's the help from
that option:
  | Normally we disable external interrupts while we are making calls to    |
  | the APM BIOS as a measure to lessen the effects of a badly behaving     |
  | BIOS implementation.  The BIOS should reenable interrupts if it         |
  | needs to.  Unfortunately, some BIOSes do not - especially those in      |
  | many of the newer IBM Thinkpads.  If you experience hangs when you      |
  | suspend, try setting this to Y.  Otherwise, say N.                      |   

Interesting.  My recollection of this when it first appeared was that it said
"may stop some machines crashing" and it didn't mention anything about
ThinkPads.  I guess my sister wasn't the only person having problems!

-- 
I'm in Utrecht.  I'd like to meet any Linux users in the area, or any other
part of the Netherlands.