Signed-off-by: kluo@nvidia.com

 drivers/ata/sata_nv.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/ata/sata_nv.c b/drivers/ata/sata_nv.c
index ed5473b..e824260 100644
--- a/drivers/ata/sata_nv.c
+++ b/drivers/ata/sata_nv.c
@@ -837,9 +837,10 @@ static void nv_adma_tf_read(struct ata_port *ap, struct ata_taskfile *tf)
 	   all shortly be aborted anyway. We assume that NCQ commands are not
 	   issued via passthrough, which is the only way that switching into
 	   ADMA mode could abort outstanding commands. */
-	nv_adma_register_mode(ap);
+	struct nv_adma_port_priv *pp = ap->private_data;
 
-	ata_tf_read(ap, tf);
+	if (pp->flags & NV_ADMA_PORT_REGISTER_MODE)
+		ata_tf_read(ap, tf);
 }
 
 static unsigned int nv_adma_tf_to_cpb(struct ata_taskfile *tf, __le16 *cpb)