Red Hat Bugzilla – Bug 122522
USB 2.0 (ehci-hcd) support for MaPower Map-H31S external USB2.0 enclosure
Last modified: 2007-11-30 17:10:42 EST
Description of problem:
When trying to use the external USB 2.0 enclosure Map-H31S from
MapPower several access and I/O problems occur, while the USB 1.1
support for this device works perfectly.
When using the ehci-hcd module it is possible to mount the device
without any error message. But when trying to access any of the files
on the external USB drive it is not possible to do so.
Copying a file from the USB hd hangs after 32 to 128 kB (128 kB in
Nautilus, 32 kB in Konqueror)
kill -9 has no direct effect when trying to kill the hanging copy
process, but after a while (about 30 sec) the copy process terminates.
It is then possible to umount the device, but trying to mont it again,
results in an error message: no blockoriented device. Using '-o loop'
which shouldn't be necessary, results in another error message: no
Reboot solves the problem. The device is then mountable again.
Version-Release number of selected component (if applicable):
Kernel version 2.4.22-2188
Steps to Reproduce:
1. mount device with ehci-hcd module loaded
2. access file on device (for example copy a file)
3. stop hanging copy process and umount
4. remount not possible
Not possible to use USB 2.0 capability
Usage of USB 2.0 capability
The Chipset used in the enclosure is GeneSys
Bus 002 Device 002: ID 05e3:0702 Genesys Logic, Inc.
After editing /usr/src/linux-2.6.5-327/drivers/usb/storage/scsiglue.c
/* limit the total size of a transfer to 120 KB */
.max_sectors = 240,
/* limit the total size of a transfer to 64 KB */
.max_sectors = 128,
and finally compiling the 2.6.5 custom kernel, resolves the issue.
OK. FC2 is going to change that parameter automatically as it