ide: add ide_set_dma() helper (v2)

* add ide_set_dma() helper and make ide_hwif_t.ide_dma_check return
  -1 when DMA needs to be disabled (== need to call ->ide_dma_off_quietly)
   0 when DMA needs to be enabled  (== need to call ->ide_dma_on)
   1 when DMA setting shouldn't be changed
* fix IDE code to use ide_set_dma() instead if using ->ide_dma_check directly

v2:
* updated for scc_pata

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

1 files changed, 2 insertions, 3 deletions

diff --git a/drivers/ide/pci/cs5520.c b/drivers/ide/pci/cs5520.c
index ba6786aabf3..400859a839f 100644
--- a/drivers/ide/pci/cs5520.c
+++ b/drivers/ide/pci/cs5520.c
@@ -132,12 +132,11 @@ static void cs5520_tune_drive(ide_drive_t *drive, u8 pio)
 
 static int cs5520_config_drive_xfer_rate(ide_drive_t *drive)
 {
-        ide_hwif_t *hwif = HWIF(drive);
-
         /* Tune the drive for PIO modes up to PIO 4 */  
         cs5520_tune_drive(drive, 4);
+
         /* Then tell the core to use DMA operations */
-        return hwif->ide_dma_on(drive);
+        return 0;
 }
 
 /*