[ltp] ultrabay hotswap

[David de Hoog]

On Fri, 2005-06-17 at 08:30 -0400, David A. Desrosiers wrote:
> > 	Would this work for swapping between a battery and DVD drive, 
> > even though one of them is not a "hd" device?  That would be really 
> > handy.
> 
> 	It will, but you'll lose DMA, which will suck for data 
> transfers or playing DVD movies in the swapped drive (it'll play very 
> "jaggedy").
> 
> 	I tried it, it worked, but it was horrible results.


Indeed, it does work - but DVD playback is unbearable and swapping the
drive out and in more than once often locks up the process running the
rescan.sh script (that comes with ibm-acpi v0.11). The only solution
that I've found to this is rebooting with the DVD in the bay.

Also, unless you boot the machine the first time with the battery in the
ultrabay you cannot get the kernel to recognise it. So if you boot with
the optical drive in the bay and then swap the ultrabay battery in, you
won't be able to determine how much charge is in the ultrabay battery
until it runs out. I've tried removing all the acpi kernel modules and
re-inserting them, and restarting acpid and I still only have BAT0, no
BAT1.

While it is feasible to hot swap, it doesn't work terribly well.

'Warm swapping' (suspend to disk then swap drive bays) locks things up
nastily.

Cheers
-- 
David de Hoog <dehood01@student.uwa.edu.au>