sata_mv: restructure mv_qc_issue

Rearrange logic in mv_qc_issue() to handle protocols
other than ATA_PROT_DMA, ATA_PROT_NCQ, and ATA_PROT_PIO.
This is in preparation for later enabling ATAPI support.

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 22 insertions, 15 deletions

diff --git a/drivers/ata/sata_mv.c b/drivers/ata/sata_mv.c
index fb3288bbd9fb..0c25f52249df 100644
--- a/drivers/ata/sata_mv.c
+++ b/drivers/ata/sata_mv.c
@@ -1565,14 +1565,26 @@ static void mv_qc_prep_iie(struct ata_queued_cmd *qc)
  */
 static unsigned int mv_qc_issue(struct ata_queued_cmd *qc)
 {
+        static int limit_warnings = 10;
         struct ata_port *ap = qc->ap;
         void __iomem *port_mmio = mv_ap_base(ap);
         struct mv_port_priv *pp = ap->private_data;
         u32 in_index;
+        unsigned int port_irqs = DONE_IRQ | ERR_IRQ;
+
+        switch (qc->tf.protocol) {
+        case ATA_PROT_DMA:
+        case ATA_PROT_NCQ:
+                mv_start_edma(ap, port_mmio, pp, qc->tf.protocol);
+                pp->req_idx = (pp->req_idx + 1) & MV_MAX_Q_DEPTH_MASK;
+                in_index = pp->req_idx << EDMA_REQ_Q_PTR_SHIFT;
+
+                /* Write the request in pointer to kick the EDMA to life */
+                writelfl((pp->crqb_dma & EDMA_REQ_Q_BASE_LO_MASK) | in_index,
+                                        port_mmio + EDMA_REQ_Q_IN_PTR_OFS);
+                return 0;
 
-        if ((qc->tf.protocol != ATA_PROT_DMA) &&
-            (qc->tf.protocol != ATA_PROT_NCQ)) {
-                static int limit_warnings = 10;
+        case ATA_PROT_PIO:
                 /*
                  * Errata SATA#16, SATA#24: warn if multiple DRQs expected.
                  *
@@ -1590,27 +1602,22 @@ static unsigned int mv_qc_issue(struct ata_queued_cmd *qc)
                                         ": attempting PIO w/multiple DRQ: "
                                         "this may fail due to h/w errata\n");
                 }
+                /* drop through */
+        case ATAPI_PROT_PIO:
+                port_irqs = ERR_IRQ;    /* leave DONE_IRQ masked for PIO */
+                /* drop through */
+        default:
                 /*
                  * We're about to send a non-EDMA capable command to the
                  * port.  Turn off EDMA so there won't be problems accessing
                  * shadow block, etc registers.
                  */
                 mv_stop_edma(ap);
-                mv_enable_port_irqs(ap, ERR_IRQ);
+                mv_edma_cfg(ap, 0, 0);
+                mv_clear_and_enable_port_irqs(ap, mv_ap_base(ap), port_irqs);
                 mv_pmp_select(ap, qc->dev->link->pmp);
                 return ata_sff_qc_issue(qc);
         }
-
-        mv_start_edma(ap, port_mmio, pp, qc->tf.protocol);
-
-        pp->req_idx = (pp->req_idx + 1) & MV_MAX_Q_DEPTH_MASK;
-        in_index = pp->req_idx << EDMA_REQ_Q_PTR_SHIFT;
-
-        /* and write the request in pointer to kick the EDMA to life */
-        writelfl((pp->crqb_dma & EDMA_REQ_Q_BASE_LO_MASK) | in_index,
-                 port_mmio + EDMA_REQ_Q_IN_PTR_OFS);
-
-        return 0;
 }
 
 static struct ata_queued_cmd *mv_get_active_qc(struct ata_port *ap)