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SubjectRe: Devices not supporting read-6....
I hate to say this... but Windows and MacOS never will generate a READ_6
or a WRITE_6 command. As such, some vendors don't support the command to
reduce firmware size and complexity.

I've run into such devices when dealing with my USB Mass Storage driver.
This driver emulates a scsi host and talks to USB Mass Storage devices.
For some devices, I have to do an on-the-fly mode translation to turn
READ_6 into READ_10, and WRITE_6 into WRITE_10. Oddly, I've found that
just writing right over the cmnd[] array in the Scsi_Cmnd structure works
perfectly.

For usb mass storage devices, I maintain my own quirky device list. But,
given the direction in which the industry seems to be heading, perhaps a
fix at a higher level (to not issue READ_6/WRITE_6) is more appropriate.

Matt Dharm

On Fri, 21 Jan 2000, Rogier Wolff wrote:

> Alan Cox wrote:
> > > {"TOSHIBA","DVD-RAM SD-W1101","*", BLIST_GHOST},
> > >
> > > which doesn't implement it.
> > >
> > > What do we do?
> > >
> > > - Blacklist it as "doesn't support read-6" and implement
> > > stuff to prevent read-6 if that flag is set?
>
> > Is this ide-scsi. ATAPI does not require legacy command modes. If
> > its atapi maybe ide-scsi isnt mapping right. If its real scsi then
> > ask Toshiba for scsi firmware. Thats just too fundamentally screwy
> > to bother with
>
> I'm told that legacy commands are currently officially depreciated, so
> we're going to see more and more of these devices.
>
> Roger.
>
>

--
Matthew Dharm Home: mdharm@one-eyed-alien.net
Engineer, Qualcomm, Inc. Work: mdharm@qualcomm.com

Sir, for the hundreth time, we do NOT carry 600-round boxes of belt-fed
suction darts!
-- Salesperson to Greg
User Friendly, 12/30/1997


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