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, 3 insertions, 4 deletions

diff --git a/drivers/ide/pci/atiixp.c b/drivers/ide/pci/atiixp.c
index 6d372c4e1d81..e7b4415adc83 100644
--- a/drivers/ide/pci/atiixp.c
+++ b/drivers/ide/pci/atiixp.c
@@ -252,21 +252,20 @@ static int atiixp_config_drive_for_dma(ide_drive_t *drive)
 
 static int atiixp_dma_check(ide_drive_t *drive)
 {
-        ide_hwif_t *hwif        = HWIF(drive);
         u8 tspeed, speed;
 
         drive->init_speed = 0;
 
         if (ide_use_dma(drive) && atiixp_config_drive_for_dma(drive))
-                return hwif->ide_dma_on(drive);
+                return 0;
 
         if (ide_use_fast_pio(drive)) {
                 tspeed = ide_get_best_pio_mode(drive, 255, 5, NULL);
                 speed = atiixp_dma_2_pio(XFER_PIO_0 + tspeed) + XFER_PIO_0;
-                hwif->speedproc(drive, speed);
+                atiixp_speedproc(drive, speed);
         }
 
-        return hwif->ide_dma_off_quietly(drive);
+        return -1;
 }
 
 /**