1 files changed, 8 insertions, 3 deletions

diff --git a/drivers/scsi/aic7xxx/aic7xxx_osm.c b/drivers/scsi/aic7xxx/aic7xxx_osm.c
index 1803ab6fc21c..2e9c38f2e8a6 100644
--- a/drivers/scsi/aic7xxx/aic7xxx_osm.c
+++ b/drivers/scsi/aic7xxx/aic7xxx_osm.c
@@ -2317,8 +2317,13 @@ static void ahc_linux_set_period(struct scsi_target *starget, int period)
 
         if (period < 9)
                 period = 9;     /* 12.5ns is our minimum */
-        if (period == 9)
-                ppr_options |= MSG_EXT_PPR_DT_REQ;
+        if (period == 9) {
+                if (spi_max_width(starget))
+                        ppr_options |= MSG_EXT_PPR_DT_REQ;
+                else
+                        /* need wide for DT and need DT for 12.5 ns */
+                        period = 10;
+        }
 
         ahc_compile_devinfo(&devinfo, shost->this_id, starget->id, 0,
                             starget->channel + 'A', ROLE_INITIATOR);
@@ -2381,7 +2386,7 @@ static void ahc_linux_set_dt(struct scsi_target *starget, int dt)
         unsigned long flags;
         struct ahc_syncrate *syncrate;
 
-        if (dt) {
+        if (dt && spi_max_width(starget)) {
                 ppr_options |= MSG_EXT_PPR_DT_REQ;
                 if (!width)
                         ahc_linux_set_width(starget, 1);