[ltp] (fwd) [PATCH] sd: implement stop_on_shutdown

[Laurent Gilson]

Hello,

> I use an external USB hard disk that I would like to be shut down after
> suspend to disk to save some energy. It contains permanently mounted
> partitions, e.g. /home, so it isn't a good idea to shut it down from
> userspace IMHO.

You will have 0 problems with userspace tools. I had the same setup and
hdparm/sdparm somewhere inside the suspend-scripts (after a sync would be
good) works just fine.

hdparm and sdparm put the device into sleep-mode. They do not shutdown the
drive. It wakes up at the next request.

But there is a big catch: the USB-enclosure has to support that command.
A lot of cheap boxes does not.

cu