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, 6 insertions, 8 deletions

diff --git a/drivers/ide/pci/it8213.c b/drivers/ide/pci/it8213.c
index 63248b6909fa..424f00bb160d 100644
--- a/drivers/ide/pci/it8213.c
+++ b/drivers/ide/pci/it8213.c
@@ -244,17 +244,15 @@ static int config_chipset_for_dma (ide_drive_t *drive)
 
 static int it8213_config_drive_for_dma (ide_drive_t *drive)
 {
-        ide_hwif_t *hwif = drive->hwif;
+        u8 pio;
 
-        if (ide_use_dma(drive)) {
-                if (config_chipset_for_dma(drive))
-                        return hwif->ide_dma_on(drive);
-        }
+        if (ide_use_dma(drive) && config_chipset_for_dma(drive))
+                return 0;
 
-        hwif->speedproc(drive, XFER_PIO_0
-                        + ide_get_best_pio_mode(drive, 255, 4, NULL));
+        pio = ide_get_best_pio_mode(drive, 255, 4, NULL);
+        it8213_tune_chipset(drive, XFER_PIO_0 + pio);
 
-        return hwif->ide_dma_off_quietly(drive);
+        return -1;
 }
 
 /**