ide: ugly messages trying to open CD drive with no media present

I get the following error messages when trying to open a CD device
(specifically, the Teac CD-ROM CD-224E) that has no media present:

hda: packet command error: status=3D0x51 { DriveReady SeekComplete Error }
hda: packet command error: error=3D0x54 { AbortedCommand LastFailedSense=0x05 }
ide: failed opcode was: unknown

This happens when a "start stop unit" command (0x1b 0 0 0 3 0 0 0 0 0)
is sent to the drive to try to close the CD-ROM tray, but this drive
doesn't have that capability (it's a slim portable-type CD-ROM), so it
reports sense key 5 (illegal request) with asc/ascq 24/0.  This is
exactly how SFF8090i says it should respond.

But ide-cd.c (in cdrom_decode_status() ) just sees sense key 5 and spews
out an error.  It then goes on to request sense data, and
cdrom_log_sense() understands this error and doesn't log it.

The patch, for kernel 2.6.20.4, suppresses this error message.

Signed-off-by: Stuart Hayes <stuart_hayes@dell.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

drivers/ide/ide-cd.c

@@ -735,6 +735,15 @@ static int cdrom_decode_status(ide_drive_t *drive, int good_stat, int *stat_ret)
 			cdrom_saw_media_change (drive);
 			/*printk("%s: media changed\n",drive->name);*/
 			return 0;
+ 		} else if ((sense_key == ILLEGAL_REQUEST) &&
+ 			   (rq->cmd[0] == GPCMD_START_STOP_UNIT)) {
+ 			/*
+ 			 * Don't print error message for this condition--
+ 			 * SFF8090i indicates that 5/24/00 is the correct
+ 			 * response to a request to close the tray if the
+ 			 * drive doesn't have that capability.
+ 			 * cdrom_log_sense() knows this!
+ 			 */
 		} else if (!(rq->cmd_flags & REQ_QUIET)) {
 			/* Otherwise, print an error. */
 			ide_dump_status(drive, "packet command error", stat);