USB: storage devices and SAT
Add the SANE SENSE flag to indicate that a device is capable of handling
more than 18-bytes of sense data. This functionality is required for
USB-ATA bridges implementing SAT. A future patch will actually enable this
function for several devices.
The logic behind this is that we can detect support for SANE_SENSE in a few ways:
1) ATA PASS THROUGH (12) or (16) execute successfully
2) SPC-3 or higher is in use
3) A previous CHECK CONDITION occurred with sense format 70-73 and had
a length greater than 18-bytes total
Signed-off-by: Ben Efros <ben@pc-doctor.com>
Signed-off-by: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c
index 09779f6..1b35e01 100644
--- a/drivers/usb/storage/scsiglue.c
+++ b/drivers/usb/storage/scsiglue.c
@@ -170,6 +170,10 @@
if (us->fflags & US_FL_CAPACITY_HEURISTICS)
sdev->guess_capacity = 1;
+ /* assume SPC3 or latter devices support sense size > 18 */
+ if (sdev->scsi_level > SCSI_SPC_2)
+ us->fflags |= US_FL_SANE_SENSE;
+
/* Some devices report a SCSI revision level above 2 but are
* unable to handle the REPORT LUNS command (for which
* support is mandatory at level 3). Since we already have