ide: add IDE_HFLAG_ABUSE_SET_DMA_MODE host flag

* Add IDE_HFLAG_ABUSE_SET_DMA_MODE host flag and use it to decide
  what to do with transfer modes < XFER_PIO_0 in ide_set_xfer_rate().

* Set IDE_HFLAG_ABUSE_SET_DMA_MODE in host drivers that need it
  (aec62xx, amd74xx, cs5520, cs5535, hpt34x, hpt366, pdc202xx_old,
  serverworks, tc86c001 and via82cxxx) and cleanup ->set_dma_mode
  methods in host drivers that don't (IDE core code guarantees that
  ->set_dma_mode will be called only for modes which are present
  in SWDMA/MWDMA/UDMA masks).

While at it:

* Add IDE_HFLAGS_HPT34X/HPT3XX/PDC202XX/SVWKS define in
  hpt34x/hpt366/pdc202xx_old/serverworks host driver.

There should be no functionality changes caused by this patch.

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

1 files changed, 8 insertions, 21 deletions

diff --git a/drivers/ide/pci/siimage.c b/drivers/ide/pci/siimage.c
index 5709c252543b..7b45eaf5afd9 100644
--- a/drivers/ide/pci/siimage.c
+++ b/drivers/ide/pci/siimage.c
@@ -278,27 +278,14 @@ static void sil_set_dma_mode(ide_drive_t *drive, const u8 speed)
 
         scsc = is_sata(hwif) ? 1 : scsc;
 
-        switch(speed) {
-                case XFER_MW_DMA_2:
-                case XFER_MW_DMA_1:
-                case XFER_MW_DMA_0:
-                        multi = dma[speed - XFER_MW_DMA_0];
-                        mode |= ((unit) ? 0x20 : 0x02);
-                        break;
-                case XFER_UDMA_6:
-                case XFER_UDMA_5:
-                case XFER_UDMA_4:
-                case XFER_UDMA_3:
-                case XFER_UDMA_2:
-                case XFER_UDMA_1:
-                case XFER_UDMA_0:
-                        multi = dma[2];
-                        ultra |= ((scsc) ? (ultra6[speed - XFER_UDMA_0]) :
-                                           (ultra5[speed - XFER_UDMA_0]));
-                        mode |= ((unit) ? 0x30 : 0x03);
-                        break;
-                default:
-                        return;
+        if (speed >= XFER_UDMA_0) {
+                multi = dma[2];
+                ultra |= (scsc ? ultra6[speed - XFER_UDMA_0] :
+                                 ultra5[speed - XFER_UDMA_0]);
+                mode |= (unit ? 0x30 : 0x03);
+        } else {
+                multi = dma[speed - XFER_MW_DMA_0];
+                mode |= (unit ? 0x20 : 0x02);
         }
 
         if (hwif->mmio) {