From mboxrd@z Thu Jan  1 00:00:00 1970
From: Martin Pitt <martin.pitt@ubuntu.com>
Date: Tue, 21 Apr 2009 07:25:09 +0000
Subject: CD-ROM tray closes automatically after eject due to random
Message-Id: <20090421072509.GF3973@piware.de>
MIME-Version: 1
Content-Type: multipart/mixed; boundary="HG+GLK89HZ1zG0kk"
List-Id: <linux-hotplug.vger.kernel.org>
To: linux-hotplug@vger.kernel.org


--HG+GLK89HZ1zG0kk
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

Hello udev developers,

https://launchpad.net/bugs/356631 reported that many people still have
the problem that after ejecting a CD, the CD-ROM tray automatically
closes again, causing the killing of fingers and CDs (or small pets :-) )

This problem came up a while ago already, and was solved with
introducing this into /lib/udev/rules.d/60-persistent-storage.rules:

  # probe filesystem metadata of optical drives which have a media inserted
  KERNEL=3D=3D"sr*", ENV{ID_CDROM_MEDIA_TRACK_COUNT}=3D=3D"?*", IMPORT{prog=
ram}=3D"vol_id --export --skip-raid --offset=3D$env{ID_CDROM_MEDIA_SESSION_=
LAST_OFFSET} $tempnode"
 =20
However, this rule (and the corresponding code in cdrom_id [1]) relies
on the track/session counts being zero if there is no CD in the drive.
However, at least with kernel 2.6.28.8 the affected people get
something like

  ID_CDROM_MEDIA_STATE=3Dblank
  ID_CDROM_MEDIA_SESSION_NEXT=3D2894
  ID_CDROM_MEDIA_SESSION_COUNT=3D19194
  ID_CDROM_MEDIA_TRACK_COUNT=3D47323

In other words, if ID_CDROM_MEDIA_STATE=3Dblank, the session/track
counts are not reliable.

Arguably this could/should be fixed in the kernel, to fix these values
to 0 if there is no CD in the drive, or it is blank. However, I
wondered if the udev rules should be more robust in that regard, and
not even ask for the number of tracks if there is no/empty CD.
Affected people verified that adding this rule before the one from
above makes things work:

  KERNEL=3D=3D"sr*", ENV{ID_CDROM_MEDIA_STATE}=3D=3D"blank", GOTO=3D"persis=
tent_storage_end"

Thanks,

Martin

[1]         if (cd_media_track_count > 0)
                printf("ID_CDROM_MEDIA_TRACK_COUNT=3D%d\n", cd_media_track_=
count);
--=20
Martin Pitt                        | http://www.piware.de
Ubuntu Developer (www.ubuntu.com)  | Debian Developer  (www.debian.org)

--HG+GLK89HZ1zG0kk
Content-Type: application/pgp-signature; name="signature.asc"
Content-Description: Digital signature
Content-Disposition: inline

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (GNU/Linux)

iEYEARECAAYFAkntdNUACgkQDecnbV4Fd/J7IQCg5GuHKGKCVOJO7HRQ8Yj7KggV
frkAoKKQ5rfT7MGyf7NrmNX3C8Awi1al
=poju
-----END PGP SIGNATURE-----

--HG+GLK89HZ1zG0kk--