When the usb-storage module forces sdev->scsi_level to SCSI_2, it should
also force starget->scsi_level to the same value. Otherwise, the SCSI
layer may attempt to issue SCSI-3 commands to the device, such as REPORT
LUNS, which it cannot handle. This can prevent the device from working
with Linux.
The AMS Venus DS3 DS2316SU2S SATA-to-SATA+USB enclosure, based on the
Oxford Semiconductor OXU921S chip, requires this patch to function
correctly on Linux. The enclosure reports a SCSI-3 SPC-2 command set
level, but does not correctly handle the REPORT LUNS SCSI command -
probably due to a bug in its firmware.
It seems likely that other USB storage enclosures with similar bugs
will also benefit from this patch.
Tony Lindgren <[email protected]> collaborated in the development of this
patch.
Signed-off-by: Paul Walmsley <[email protected]>
- Paul
diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c
index 4837524..4ef5527 100644
--- a/drivers/usb/storage/scsiglue.c
+++ b/drivers/usb/storage/scsiglue.c
@@ -109,7 +109,7 @@ static int slave_configure(struct scsi_d
* data comes from.
*/
if (sdev->scsi_level < SCSI_2)
- sdev->scsi_level = SCSI_2;
+ sdev->scsi_level = sdev->sdev_target->scsi_level = SCSI_2;
/* According to the technical support people at Genesys Logic,
* devices using their chips have problems transferring more than
@@ -162,7 +162,7 @@ static int slave_configure(struct scsi_d
* a Get-Max-LUN request, we won't lose much by setting the
* revision level down to 2. The only devices that would be
* affected are those with sparse LUNs. */
- sdev->scsi_level = SCSI_2;
+ sdev->scsi_level = sdev->sdev_target->scsi_level = SCSI_2;
/* USB-IDE bridges tend to report SK = 0x04 (Non-recoverable
* Hardware Error) when any low-level error occurs,