hdparm -i uses the HDIO_GET_IDENTITY ioctl, which returns drive->id.
It doesn't obtain the ID from the drive. hdparm -I asks the
identity from the drive.
hdparm --help gives some hints:
-i display drive identification
-I read drive identification directly from drive
and the man page is quite clear:
-i Display the identification info that was obtained
from the drive at boot time, if available. This is
a feature of modern IDE drives, and may not be sup
ported by older devices. The data returned may or
may not be current, depending on activity since
booting the system. However, the current multiple
sector mode count is always shown. For a more
detailed interpretation of the identification info,
refer to AT Attachment Interface for Disk Drives
(ANSI ASC X3T9.2 working draft, revision 4a, April
19/93).
-I Request identification info directly from the
drive, which is displayed in its raw form with no
endian changes or corrections. Text strings may
appear mangled when using -I but that is NOT a bug.
Otherwise similar to the -i option.
-- Russell King (rmk@arm.linux.org.uk) The developer of ARM Linux http://www.arm.linux.org.uk/personal/aboutme.html- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/