How to get an IDE Hard Reset, not a Soft Reset?

[Ralph Corderoy <ralph@inputplus.co.uk>]

Hi,

As I understand it, an IDE hard drive can be reset in three ways.  A
power-on reset, a hard reset caused by pin 1 (RESET-) on the IDE
connector, and a soft reset (bit SRST in the device control register).
RESET- is held low on a power on, but can also be used later to do a
hard reset.

I can see there's an ioctl to do a soft reset, calling ide_do_reset(),
but how, from user space, can I do a hard reset?  If it isn't possible
from user space, is it possible in the kernel?  Pointers welcome.

Hard resets refreshes parts other soft resets cannot reach.  E.g. the
Expire flag (bit 4) of word 128 in the identify device info.

(Please keep me CC'd.)

Cheers,


Ralph.