On Feb 5, Ken Hornstein wrote
> >When events mechanism will be in place, the driver will be notified of
> >APM events and will be able to issue the reset before trying a command ...
> 
> But unfortunately APM events don't have anything to do with disk
> powerdown :-(

For suspend/resume this still may help.

> 
> I think the only good long-term solution is to make the driver do it's
> own power management.
> 

Agreed. But not at the driver level. This needs to be done at a higther level,
so that this can benefit for SCSI disks (and possibly others ?) too.
I have some idea for moving update to a kernel thread, which could have
an intelligent buffer sync policie (no need to wakeup the disk when the only
change to flush on disk is an atime update, for example). This kernel
thread could also do disk PM.
Unfortunably I don't have the time to work on this now.

--
Manuel Bouyer <bouyer@antioche.eu.org>
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