[PATCH] libata: interrupt driven pio for LLD

[deliverable/linux.git] / drivers / scsi / libata-core.c

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index cc2d1308826ea5c5a51ce2ae53da87466f766a0b..f8a590e59f107472acf03174075d8521c1810766 100644 (file)
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -3356,6 +3356,25 @@ int ata_qc_issue_prot(struct ata_queued_cmd *qc)
 {
        struct ata_port *ap = qc->ap;
 
+       /* Use polling pio if the LLD doesn't handle
+        * interrupt driven pio and atapi CDB interrupt.
+        */
+       if (ap->flags & ATA_FLAG_PIO_POLLING) {
+               switch (qc->tf.protocol) {
+               case ATA_PROT_PIO:
+               case ATA_PROT_ATAPI:
+               case ATA_PROT_ATAPI_NODATA:
+                       qc->tf.flags |= ATA_TFLAG_POLLING;
+                       break;
+               case ATA_PROT_ATAPI_DMA:
+                       if (qc->dev->flags & ATA_DFLAG_CDB_INTR)
+                               BUG();
+                       break;
+               default:
+                       break;
+               }
+       }
+
        /* select the device */
        ata_dev_select(ap, qc->dev->devno, 1, 0);