Thanks, I think the status of the fujitsu scanners with USB interface should not be reported 'good'.
Oliver Am Montag 05 April 2004 22:23 schrieb m. allan noah: > so, i tracked it down using usb snoopy in windows. the problem is simple > to explain, but harder to fix: > > most scsi commands that use a data block after the command block (mode > select, set window, scan) are formatted differently when sent via usb. the > command block is sent first, in a single urb, padded to 31 bytes with null > bytes. then the data block(s) are sent in another urb, not padded. > > the existing fujitsu code is very scsi specific, and only uses one buffer > for scsi cmd/data to the do_cmd() function. this means that the caller has > to either pad the single buffer with just the right number of 0's in the > middle of the buffer, or the do_usb_cmd() function will have to break the > buffer inhalf, and pad the data itself. > > for an example, see fujitsu_set_sleep_mode(). > > you see this problem only with scanning duplex or back side because the > code at line 3112 (talks about opcode==SCAN) is wrong. it should take the > last one or two bytes and send as adifferent urb, rather than assuming 00. > > i have started a new version of the fujitsu backend, which uses a command > and a data buffer to do_cmd() but have been far too busy to make much > headway. take a shot if you would like.
