ide: add ide_dma_prepare() helper

* Add ide_dma_prepare() helper.

* Convert ide_issue_pc() and do_rw_taskfile() to use it.

* Make ide_build_sglist() static.

There should be no functional changes caused by this patch.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

1 files changed, 10 insertions, 1 deletions

diff --git a/drivers/ide/ide-dma.c b/drivers/ide/ide-dma.c
index b430898bbcd6..cf5897f5533f 100644
--- a/drivers/ide/ide-dma.c
+++ b/drivers/ide/ide-dma.c
@@ -128,7 +128,7 @@ int ide_dma_good_drive(ide_drive_t *drive)
  *      operate in a portable fashion.
  */
 
-int ide_build_sglist(ide_drive_t *drive, struct ide_cmd *cmd)
+static int ide_build_sglist(ide_drive_t *drive, struct ide_cmd *cmd)
 {
         ide_hwif_t *hwif = drive->hwif;
         struct scatterlist *sg = hwif->sg_table;
@@ -563,3 +563,12 @@ int ide_allocate_dma_engine(ide_hwif_t *hwif)
         return 0;
 }
 EXPORT_SYMBOL_GPL(ide_allocate_dma_engine);
+
+int ide_dma_prepare(ide_drive_t *drive, struct ide_cmd *cmd)
+{
+        if ((drive->dev_flags & IDE_DFLAG_USING_DMA) == 0 ||
+            ide_build_sglist(drive, cmd) == 0 ||
+            drive->hwif->dma_ops->dma_setup(drive, cmd))
+                return 1;
+        return 0;
+}