A Tale of Two SCSI CD ROMS

[Janina Sajka]

And, it's a tale of woe! <grin>

I am trying to figure out why one of my ide-scsi CD ROM devices works just like it should, while the second one doesn't.

I suppose it could be something to do with the complexity of the hardware setup. This is an IBM Thinkpad T20 attached to
an IBM docking station--at least it's attached when both devices are present together. The one CD ROM, and it's a CDRW,
hence the ide-scsi, is on the Thinkpad itself in an IBM Ultrabay, as they call it. The second is in the dock, also in an
ultrabay.

I have no problems mounting the first, and no success at all mounting the second. In fact, when I try, I hard-hang the
system so that I have to force power off--not even a ctrl-alt-del does the trick.

The devices are definitely there. /proc/scsi/scsi reports:


Attached devices:
/Host: scsi0 Channel: 00 Id: 00 Lun: 00
  Vendor: MATSHITA Model: UJDA310          Rev: 3.53
  Type:   CD-ROM                           ANSI SCSI revision: 02
Host: scsi0 Channel: 00 Id: 01 Lun: 00
  Vendor: TEAC     Model: CD-224E          Rev: 2.7B
  Type:   CD-ROM                           ANSI SCSI revision: 02
Host: scsi1 Channel: 00 Id: 06 Lun: 00
  Vendor: CWS ORB2 Model: -SE U ID 6       Rev: D29



I have /dev/scd0 and /dev/scd1. If I try, just for grins, mounting /dev/hde (the second device), I get a very polite error message suggesting that I should be using my ide-scsi.

What I don't seem to have--and this is where I begin to lose my understanding of how this all works--is sr0 and sr1. These are referred to as the system boots--but they don't seem to be anywhere around:

Mar  4 15:31:59 toccata kernel: Kernel command line: BOOT_IMAGE=current ro root=301 BOOT_FILE=/boot/vmlinuz-2.4.2 hdc=ide-scsi hde=ide-scsi
Mar  4 15:31:59 toccata kernel: ide_setup: hdc=ide-scsi
Mar  4 15:31:59 toccata kernel: ide_setup: hde=ide-scsi
...
Mar  4 15:31:59 toccata kernel:     ide1: BM-DMA at 0x1c18-0x1c1f, BIOS settings: hdc:pio, hdd:pio
Mar  4 15:31:59 toccata kernel: CMD648: IDE controller on PCI bus 08 dev 08
Mar  4 15:31:59 toccata kernel: PCI: Found IRQ 11 for device 08:01.0
Mar  4 15:31:59 toccata kernel: PCI: The same IRQ used for device 00:02.1
Mar  4 15:31:59 toccata kernel: CMD648: chipset revision 1
Mar  4 15:31:59 toccata kernel: CMD648: 100%% native mode on irq 11
Mar  4 15:31:59 toccata kernel:     ide2: BM-DMA at 0x2000-0x2007, BIOS settings: hde:DMA, hdf:pio
Mar  4 15:31:59 toccata kernel:     ide3: BM-DMA at 0x2008-0x200f, BIOS settings: hdg:pio, hdh:pio
Mar  4 15:31:59 toccata kernel: hda: IBM-DJSA-220, ATA DISK drive
Mar  4 15:31:59 toccata kernel: hdc: UJDA310, ATAPI CD/DVD-ROM drive
Mar  4 15:31:59 toccata kernel: hde: CD-224E, ATAPI CD/DVD-ROM drive
Mar  4 15:31:59 toccata kernel: ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
Mar  4 15:31:59 toccata kernel: ide1 at 0x170-0x177,0x376 on irq 15
Mar  4 15:31:59 toccata kernel: ide2 at 0x2020-0x2027,0x2016 on irq 11
Mar  4 15:31:59 toccata kernel: hda: 39070080 sectors (20004 MB) w/1874KiB Cache, CHS=2584/240/63, UDMA(33)
Mar  4 15:31:59 toccata kernel: Partition check:
Mar  4 15:31:59 toccata kernel:  hda: hda1 hda2 hda3 hda4 < hda5 hda6 hda7 hda8 hda9 hda10 >
...
Mar  4 15:31:59 toccata kernel: SCSI subsystem driver Revision: 1.00
Mar  4 15:31:59 toccata kernel: scsi0 : SCSI host adapter emulation for IDE ATAPI devices
Mar  4 15:31:59 toccata kernel:   Vendor: MATSHITA  Model: UJDA310           Rev: 3.53
Mar  4 15:31:59 toccata kernel:   Type:   CD-ROM                             ANSI SCSI revision: 02
Mar  4 15:31:59 toccata kernel:   Vendor: TEAC      Model: CD-224E           Rev: 2.7B
Mar  4 15:31:59 toccata kernel:   Type:   CD-ROM                             ANSI SCSI revision: 02
Mar  4 15:31:59 toccata kernel: Detected scsi CD-ROM sr0 at scsi0, channel 0, id 0, lun 0
Mar  4 15:31:59 toccata kernel: Detected scsi CD-ROM sr1 at scsi0, channel 0, id 1, lun 0
Mar  4 15:31:59 toccata kernel: sr0: scsi3-mmc drive: 20x/20x writer cd/rw xa/form2 cdda tray
Mar  4 15:31:59 toccata kernel: Uniform CD-ROM driver Revision: 3.12
Mar  4 15:31:59 toccata kernel: sr1: scsi3-mmc drive: 24x/24x cd/rw xa/form2 cdda tray
...

I can't imagine the SR0 and SR1 device designations are meaningless--but I don't see them in /dev.

Any advice most appreciated.


-- 

				Janina Sajka, Director
				Technology Research and Development
				Governmental Relations Group
				American Foundation for the Blind (AFB)

janina at afb.net
(202) 408-8175
http://www.afb.org/gov.html


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