firewire: fw-sbp2: relax SCSI DMA alignment

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/firewire/fw-sbp2.c b/drivers/firewire/fw-sbp2.c
index c7aba5c..ea62e82 100644
--- a/drivers/firewire/fw-sbp2.c
+++ b/drivers/firewire/fw-sbp2.c
@@ -1518,11 +1518,8 @@
 
 	sdev->allow_restart = 1;
 
-	/*
-	 * Update the dma alignment (minimum alignment requirements for
-	 * start and end of DMA transfers) to be a sector
-	 */
-	blk_queue_update_dma_alignment(sdev->request_queue, 511);
+	/* SBP-2 requires quadlet alignment of the data buffers. */
+	blk_queue_update_dma_alignment(sdev->request_queue, 4 - 1);
 
 	if (lu->tgt->workarounds & SBP2_WORKAROUND_INQUIRY_36)
 		sdev->inquiry_len = 36;