3 files changed, 15 insertions, 6 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 3fd7c7932707..b35fdcb104ec 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4821,6 +4821,14 @@ unsigned int ata_qc_issue_prot(struct ata_queued_cmd *qc)
                 }
         }
 
+        /* Some controllers show flaky interrupt behavior after
+         * setting xfer mode.  Use polling instead.
+         */
+        if (unlikely(qc->tf.command == ATA_CMD_SET_FEATURES &&
+                     qc->tf.feature == SETFEATURES_XFER) &&
+            (ap->flags & ATA_FLAG_SETXFER_POLLING))
+                qc->tf.flags |= ATA_TFLAG_POLLING;
+
         /* select the device */
         ata_dev_select(ap, qc->dev->devno, 1, 0);
 
diff --git a/drivers/ata/pata_via.c b/drivers/ata/pata_via.c
index ee93dd0169be..a9077b617b8d 100644
--- a/drivers/ata/pata_via.c
+++ b/drivers/ata/pata_via.c
@@ -418,7 +418,7 @@ static int via_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
         /* Early VIA without UDMA support */
         static struct ata_port_info via_mwdma_info = {
                 .sht = &via_sht,
-                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SRST,
+                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SETXFER_POLLING,
                 .pio_mask = 0x1f,
                 .mwdma_mask = 0x07,
                 .port_ops = &via_port_ops
@@ -426,7 +426,7 @@ static int via_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
         /* Ditto with IRQ masking required */
         static struct ata_port_info via_mwdma_info_borked = {
                 .sht = &via_sht,
-                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SRST,
+                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SETXFER_POLLING,
                 .pio_mask = 0x1f,
                 .mwdma_mask = 0x07,
                 .port_ops = &via_port_ops_noirq,
@@ -434,7 +434,7 @@ static int via_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
         /* VIA UDMA 33 devices (and borked 66) */
         static struct ata_port_info via_udma33_info = {
                 .sht = &via_sht,
-                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SRST,
+                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SETXFER_POLLING,
                 .pio_mask = 0x1f,
                 .mwdma_mask = 0x07,
                 .udma_mask = 0x7,
@@ -443,7 +443,7 @@ static int via_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
         /* VIA UDMA 66 devices */
         static struct ata_port_info via_udma66_info = {
                 .sht = &via_sht,
-                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SRST,
+                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SETXFER_POLLING,
                 .pio_mask = 0x1f,
                 .mwdma_mask = 0x07,
                 .udma_mask = 0x1f,
@@ -452,7 +452,7 @@ static int via_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
         /* VIA UDMA 100 devices */
         static struct ata_port_info via_udma100_info = {
                 .sht = &via_sht,
-                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SRST,
+                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SETXFER_POLLING,
                 .pio_mask = 0x1f,
                 .mwdma_mask = 0x07,
                 .udma_mask = 0x3f,
@@ -461,7 +461,7 @@ static int via_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
         /* UDMA133 with bad AST (All current 133) */
         static struct ata_port_info via_udma133_info = {
                 .sht = &via_sht,
-                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SRST,
+                .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SETXFER_POLLING,
                 .pio_mask = 0x1f,
                 .mwdma_mask = 0x07,
                 .udma_mask = 0x7f,      /* FIXME: should check north bridge */
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 6013211ac7de..8b57b6a806cc 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -178,6 +178,7 @@ enum {
         ATA_FLAG_DEBUGMSG       = (1 << 13),
         ATA_FLAG_DETECT_POLLING = (1 << 14), /* detect device presence by
                                               * polling IDENTIFY */
+        ATA_FLAG_SETXFER_POLLING= (1 << 15), /* use polling for SETXFER */
 
         /* The following flag belongs to ap->pflags but is kept in
          * ap->flags because it's referenced in many LLDs and will be