Re: IDE and hot-swap disk caddies

Jeremy Jackson (
Mon, 25 Mar 2002 21:28:21 -0800

At the interface level, there is some support.
Look at hdparm's -b option to tristate the bus.
But that's the whole bus. If the controller implements
master/slave on one cable, you're hosed, electrically.
It's the whole interface. 95% of controlers are like this.

Intel's PIIX can do master/slave on separate ports, but
then you loose one bus. Laptops with bays also do things
like this, but that's special hardware, hard to get programming
specs for.

I think if you add the drive *after* boot, it doesn't
have the benefit of the BIOS setting up PIO/UDMA modes,
so I would try the hdparm -X speed settings also.


----- Original Message -----
From: "John Summerfield" <>
Sent: Monday, March 25, 2002 3:16 PM
Subject: Re: IDE and hot-swap disk caddies

> > > The device is hot-swap capable and has a switch (others have a key)
> > > that locks the drive in and powers it up; in the other position the
> > > drive is powered down and can be removed.
> >
> > Linux doesn't support IDE hot swap at the drive level. Its basically
> > waiting people to want it enough to either fund it or go write the code
> >
> What needs to be done? How extensive is the surgery needed?

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at