Linux 2.6.x wrongly recognizes USB 2.0 DVD writer

Linux 2.6.x wrongly recognizes USB 2.0 DVD writer

[Ganesan R]

Hi,

I have a NEC ND-2500A DVD writer in a ByteCC USB 2.0 external enclosure.
It's recognized perfectly in 2.4.27 (Debian kernel-image-2.4.27-1-686
package)

========
scsi2 : SCSI emulation for USB Mass Storage
   Vendor: _NEC      Model: DVD_RW ND-2500A
   Type:   CD-ROM    ANSI SCSI revision: 02
Attached scsi CD-ROM sr1 at scsi2, channel 0, id 0, lun 0
sr1: scsi-1 drive
USB Mass Storage support registered.
========

When I boot 2.6.8 (Debian kernel-image-2.6.8-1-686 package), I get

========
scsi3 : SCSI emulation for USB Mass Storage devices
  Vendor: Revoltec  Model: USB/IDE Bridge (  Rev: 0103
  Type:   Direct-Access                      ANSI SCSI revision: 02
Attached scsi removable disk sdb at scsi3, channel 0, id 0, lun 0
USB Mass Storage device found at 4
========

Any body else facing this problem?

Ganesan
    
  

Re: Linux 2.6.x wrongly recognizes USB 2.0 DVD writer

[John Stoffel]

Ganesan> I have a NEC ND-2500A DVD writer in a ByteCC USB 2.0 external
Ganesan> enclosure.  It's recognized perfectly in 2.4.27 (Debian
Ganesan> kernel-image-2.4.27-1-686 package)

I've got a ByteCC external enclosure too, and I can't get it to work
reliably under Linux or Windows under Firewire.  I'd return it and get
something better.

Also, the 2.6 ieee1394 sbp2 driver isn't the best at detecting these
things.  And if it does, it doesn't always work well with drives in
there as well.  I've been having tons of problems and I basically gave
up.  

John

Re: Linux 2.6.x wrongly recognizes USB 2.0 DVD writer

[Ganesan R]

John Stoffel wrote:

>Ganesan> I have a NEC ND-2500A DVD writer in a ByteCC USB 2.0 external
>Ganesan> enclosure.  It's recognized perfectly in 2.4.27 (Debian
>Ganesan> kernel-image-2.4.27-1-686 package)
>
>I've got a ByteCC external enclosure too, and I can't get it to work
>reliably under Linux or Windows under Firewire.  I'd return it and get
>something better.
>
Thanks for the info. As I mentioned, the enclosure works flawlessly for 
me under 2.4.27. It's getting detected incorrectly only in 2.6.x. 
Another user reported a similar problem but was able to get dvd burning 
working by removing the checks from the writing tool. So, it looks like 
detection has been messed up only in 2.6.x.

Once again, 2.6.8 reports it as

======
scsi3 : SCSI emulation for USB Mass Storage devices
  Vendor: Revoltec  Model: USB/IDE Bridge (  Rev: 0103
  Type:   Direct-Access                      ANSI SCSI revision: 02
Attached scsi removable disk sdb at scsi3, channel 0, id 0, lun 0
======

whereas 2.4.27 correctly reports

========                                                               
scsi2 : SCSI emulation for USB Mass Storage                            
   Vendor: _NEC      Model: DVD_RW ND-2500A                            
   Type:   CD-ROM    ANSI SCSI revision: 02                            
Attached scsi CD-ROM sr1 at scsi2, channel 0, id 0, lun 0              
sr1: scsi-1 drive                                                      
USB Mass Storage support registered.                                   
========                                                               

I checked the kernel sources. Sure enough, 
drivers/usb/storage/unusual_devs.h
has a new entry in the 2.6 tree:

========
/* <torsten.scherer@uni-bielefeld.de>: I don't know the name of the bridge
 * manufacturer, but I've got an external USB drive by the Revoltec company
 * that needs this. otherwise the drive is recognized as /dev/sda, but any
 * access to it blocks indefinitely.
 */
UNUSUAL_DEV(  0x0402, 0x5621, 0x0103, 0x0103,
        "Revoltec",
        "USB/IDE Bridge (ATA/ATAPI)",
        US_SC_DEVICE, US_PR_DEVICE, NULL, US_FL_FIX_INQUIRY),
========

I have not yet tested after removing this entry, but this looks to be 
the likely problem. The enclosure actually supports both 3.5 IDE hard 
disks as well as 5.25 CD/DVD drives. I have no clue why this entry 
should cause the drive to be wrongly detected. CCing linux-usb-devel for 
help.

Please CC me on replies to linux-usb-devel since I am not subscribed to 
that list. Thanks.

Ganesan

Re: Linux 2.6.x wrongly recognizes USB 2.0 DVD writer

[John Stoffel]

Ganesan> Thanks for the info. As I mentioned, the enclosure works
Ganesan> flawlessly for me under 2.4.27. It's getting detected
Ganesan> incorrectly only in 2.6.x.  Another user reported a similar
Ganesan> problem but was able to get dvd burning working by removing
Ganesan> the checks from the writing tool. So, it looks like detection
Ganesan> has been messed up only in 2.6.x.

I'm an idiot.  I mis-read your initial post thinking it was like my
ByteCC which has the dual Firewire/USB ports and since I can't get
EITHER interface type to work reliablely, I've given up on it for now.

What's the output of 'lsusb'?  You want to see what the vendor/product
ID is as a comparison.  I should check mine again under USB and see
what happens under 2.6.8, though earlier it would just hang the entire
system after copying a GB or two of data.  At least under FireWire
when it hung, I could recover the system without having to reboot.

Gah... time for more caffeine.

Re: [linux-usb-devel] Re: Linux 2.6.x wrongly recognizes USB 2.0 DVD writer

[Alan Stern]

On Thu, 14 Oct 2004, Ganesan R wrote:

> Thanks for the info. As I mentioned, the enclosure works flawlessly for 
> me under 2.4.27. It's getting detected incorrectly only in 2.6.x. 
> Another user reported a similar problem but was able to get dvd burning 
> working by removing the checks from the writing tool. So, it looks like 
> detection has been messed up only in 2.6.x.
> 
> Once again, 2.6.8 reports it as
> 
> ======
> scsi3 : SCSI emulation for USB Mass Storage devices
>   Vendor: Revoltec  Model: USB/IDE Bridge (  Rev: 0103
>   Type:   Direct-Access                      ANSI SCSI revision: 02
> Attached scsi removable disk sdb at scsi3, channel 0, id 0, lun 0
> ======
> 
> whereas 2.4.27 correctly reports
> 
> ========                                                               
> scsi2 : SCSI emulation for USB Mass Storage                            
>    Vendor: _NEC      Model: DVD_RW ND-2500A                            
>    Type:   CD-ROM    ANSI SCSI revision: 02                            
> Attached scsi CD-ROM sr1 at scsi2, channel 0, id 0, lun 0              
> sr1: scsi-1 drive                                                      
> USB Mass Storage support registered.                                   
> ========                                                               
> 
> I checked the kernel sources. Sure enough, 
> drivers/usb/storage/unusual_devs.h
> has a new entry in the 2.6 tree:
> 
> ========
> /* <torsten.scherer@uni-bielefeld.de>: I don't know the name of the bridge
>  * manufacturer, but I've got an external USB drive by the Revoltec company
>  * that needs this. otherwise the drive is recognized as /dev/sda, but any
>  * access to it blocks indefinitely.
>  */
> UNUSUAL_DEV(  0x0402, 0x5621, 0x0103, 0x0103,
>         "Revoltec",
>         "USB/IDE Bridge (ATA/ATAPI)",
>         US_SC_DEVICE, US_PR_DEVICE, NULL, US_FL_FIX_INQUIRY),
> ========
> 
> I have not yet tested after removing this entry, but this looks to be 
> the likely problem. The enclosure actually supports both 3.5 IDE hard 
> disks as well as 5.25 CD/DVD drives. I have no clue why this entry 
> should cause the drive to be wrongly detected. CCing linux-usb-devel for 
> help.

Certainly that entry is the problem.  It has been removed in the latest 
development kernels; it may already be gone in 2.6.9-rc4.

Alan Stern

Re: [linux-usb-devel] Re: Linux 2.6.x wrongly recognizes USB 2.0 DVD writer (solved)

[Ganesan R]

On Thu, Oct 14, 2004 at 10:26:53AM -0400, Alan Stern wrote:
> 
> On Thu, 14 Oct 2004, Ganesan R wrote:
> > 
> > I checked the kernel sources. Sure enough, 
> > drivers/usb/storage/unusual_devs.h
> > has a new entry in the 2.6 tree:
> > 
> > ========
> > /* <torsten.scherer@uni-bielefeld.de>: I don't know the name of the bridge
> >  * manufacturer, but I've got an external USB drive by the Revoltec company
> >  * that needs this. otherwise the drive is recognized as /dev/sda, but any
> >  * access to it blocks indefinitely.
> >  */
> > UNUSUAL_DEV(  0x0402, 0x5621, 0x0103, 0x0103,
> >         "Revoltec",
> >         "USB/IDE Bridge (ATA/ATAPI)",
> >         US_SC_DEVICE, US_PR_DEVICE, NULL, US_FL_FIX_INQUIRY),
> > ========
> > 
> > I have not yet tested after removing this entry, but this looks to be 
> > the likely problem. The enclosure actually supports both 3.5 IDE hard 
> > disks as well as 5.25 CD/DVD drives. I have no clue why this entry 
> > should cause the drive to be wrongly detected. CCing linux-usb-devel for 
> > help.
> 
> Certainly that entry is the problem.  It has been removed in the latest 
> development kernels; it may already be gone in 2.6.9-rc4.

I removed that entry and recompiled 2.6.8. The drive is now recognized
properly again in 2.6.8. Thanks to every one who helped.

Ganesan