libata-sff: separate out BMDMA qc_issue

Separate out ata_bmdma_qc_issue() from ata_sff_qc_issue() such that
ata_sff_qc_issue() only deals with non-BMDMA SFF protocols (PIO and
nodata) while ata_bmdma_qc_issue() deals with the BMDMA protocols and
uses ata_sff_qc_issue() for non-DMA commands.  All the users are
updated accordingly.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 67 insertions, 45 deletions

diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c
index 6f52b598b8d2..19ddf924944f 100644
--- a/drivers/ata/libata-sff.c
+++ b/drivers/ata/libata-sff.c
@@ -1379,15 +1379,11 @@ fsm_start:
 }
 
 /**
- *      ata_sff_qc_issue - issue taskfile to device in proto-dependent manner
+ *      ata_sff_qc_issue - issue taskfile to a SFF controller
  *      @qc: command to issue to device
  *
- *      Using various libata functions and hooks, this function
- *      starts an ATA command.  ATA commands are grouped into
- *      classes called "protocols", and issuing each type of protocol
- *      is slightly different.
- *
- *      May be used as the qc_issue() entry in ata_port_operations.
+ *      This function issues a PIO or NODATA command to a SFF
+ *      controller.
  *
  *      LOCKING:
  *      spin_lock_irqsave(host lock)
@@ -1402,23 +1398,8 @@ unsigned int ata_sff_qc_issue(struct ata_queued_cmd *qc)
         /* 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_NODATA:
-                case ATAPI_PROT_PIO:
-                case ATAPI_PROT_NODATA:
-                        qc->tf.flags |= ATA_TFLAG_POLLING;
-                        break;
-                case ATAPI_PROT_DMA:
-                        if (qc->dev->flags & ATA_DFLAG_CDB_INTR)
-                                /* see ata_dma_blacklisted() */
-                                BUG();
-                        break;
-                default:
-                        break;
-                }
-        }
+        if (ap->flags & ATA_FLAG_PIO_POLLING)
+                qc->tf.flags |= ATA_TFLAG_POLLING;
 
         /* select the device */
         ata_dev_select(ap, qc->dev->devno, 1, 0);
@@ -1437,15 +1418,6 @@ unsigned int ata_sff_qc_issue(struct ata_queued_cmd *qc)
 
                 break;
 
-        case ATA_PROT_DMA:
-                WARN_ON_ONCE(qc->tf.flags & ATA_TFLAG_POLLING);
-
-                ap->ops->sff_tf_load(ap, &qc->tf);  /* load tf registers */
-                ap->ops->bmdma_setup(qc);           /* set up bmdma */
-                ap->ops->bmdma_start(qc);           /* initiate bmdma */
-                ap->hsm_task_state = HSM_ST_LAST;
-                break;
-
         case ATA_PROT_PIO:
                 if (qc->tf.flags & ATA_TFLAG_POLLING)
                         ata_qc_set_polling(qc);
@@ -1490,18 +1462,6 @@ unsigned int ata_sff_qc_issue(struct ata_queued_cmd *qc)
                         ata_sff_queue_pio_task(ap, 0);
                 break;
 
-        case ATAPI_PROT_DMA:
-                WARN_ON_ONCE(qc->tf.flags & ATA_TFLAG_POLLING);
-
-                ap->ops->sff_tf_load(ap, &qc->tf);  /* load tf registers */
-                ap->ops->bmdma_setup(qc);           /* set up bmdma */
-                ap->hsm_task_state = HSM_ST_FIRST;
-
-                /* send cdb by polling if no cdb interrupt */
-                if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
-                        ata_sff_queue_pio_task(ap, 0);
-                break;
-
         default:
                 WARN_ON_ONCE(1);
                 return AC_ERR_SYSTEM;
@@ -2618,6 +2578,7 @@ const struct ata_port_operations ata_bmdma_port_ops = {
         .post_internal_cmd      = ata_bmdma_post_internal_cmd,
 
         .qc_prep                = ata_bmdma_qc_prep,
+        .qc_issue               = ata_bmdma_qc_issue,
 
         .bmdma_setup            = ata_bmdma_setup,
         .bmdma_start            = ata_bmdma_start,
@@ -2782,6 +2743,67 @@ void ata_bmdma_dumb_qc_prep(struct ata_queued_cmd *qc)
 EXPORT_SYMBOL_GPL(ata_bmdma_dumb_qc_prep);
 
 /**
+ *      ata_bmdma_qc_issue - issue taskfile to a BMDMA controller
+ *      @qc: command to issue to device
+ *
+ *      This function issues a PIO, NODATA or DMA command to a
+ *      SFF/BMDMA controller.  PIO and NODATA are handled by
+ *      ata_sff_qc_issue().
+ *
+ *      LOCKING:
+ *      spin_lock_irqsave(host lock)
+ *
+ *      RETURNS:
+ *      Zero on success, AC_ERR_* mask on failure
+ */
+unsigned int ata_bmdma_qc_issue(struct ata_queued_cmd *qc)
+{
+        struct ata_port *ap = qc->ap;
+
+        /* see ata_dma_blacklisted() */
+        BUG_ON((ap->flags & ATA_FLAG_PIO_POLLING) &&
+               qc->tf.protocol == ATAPI_PROT_DMA);
+
+        /* defer PIO handling to sff_qc_issue */
+        if (!ata_is_dma(qc->tf.protocol))
+                return ata_sff_qc_issue(qc);
+
+        /* select the device */
+        ata_dev_select(ap, qc->dev->devno, 1, 0);
+
+        /* start the command */
+        switch (qc->tf.protocol) {
+        case ATA_PROT_DMA:
+                WARN_ON_ONCE(qc->tf.flags & ATA_TFLAG_POLLING);
+
+                ap->ops->sff_tf_load(ap, &qc->tf);  /* load tf registers */
+                ap->ops->bmdma_setup(qc);           /* set up bmdma */
+                ap->ops->bmdma_start(qc);           /* initiate bmdma */
+                ap->hsm_task_state = HSM_ST_LAST;
+                break;
+
+        case ATAPI_PROT_DMA:
+                WARN_ON_ONCE(qc->tf.flags & ATA_TFLAG_POLLING);
+
+                ap->ops->sff_tf_load(ap, &qc->tf);  /* load tf registers */
+                ap->ops->bmdma_setup(qc);           /* set up bmdma */
+                ap->hsm_task_state = HSM_ST_FIRST;
+
+                /* send cdb by polling if no cdb interrupt */
+                if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
+                        ata_sff_queue_pio_task(ap, 0);
+                break;
+
+        default:
+                WARN_ON(1);
+                return AC_ERR_SYSTEM;
+        }
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(ata_bmdma_qc_issue);
+
+/**
  *      ata_bmdma_error_handler - Stock error handler for BMDMA controller
  *      @ap: port to handle error for
  *