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, 2 insertions, 12 deletions

diff --git a/drivers/ide/pci/slc90e66.c b/drivers/ide/pci/slc90e66.c
index eb4445b229ed..dbbb46819a2d 100644
--- a/drivers/ide/pci/slc90e66.c
+++ b/drivers/ide/pci/slc90e66.c
@@ -91,19 +91,9 @@ static void slc90e66_set_dma_mode(ide_drive_t *drive, const u8 speed)
         pci_read_config_word(dev, 0x48, &reg48);
         pci_read_config_word(dev, 0x4a, &reg4a);
 
-        switch(speed) {
-                case XFER_UDMA_4:       u_speed = 4 << (drive->dn * 4); break;
-                case XFER_UDMA_3:       u_speed = 3 << (drive->dn * 4); break;
-                case XFER_UDMA_2:       u_speed = 2 << (drive->dn * 4); break;
-                case XFER_UDMA_1:       u_speed = 1 << (drive->dn * 4); break;
-                case XFER_UDMA_0:       u_speed = 0 << (drive->dn * 4); break;
-                case XFER_MW_DMA_2:
-                case XFER_MW_DMA_1:
-                case XFER_SW_DMA_2:     break;
-                default:                return;
-        }
-
         if (speed >= XFER_UDMA_0) {
+                u_speed = (speed - XFER_UDMA_0) << (drive->dn * 4);
+
                 if (!(reg48 & u_flag))
                         pci_write_config_word(dev, 0x48, reg48|u_flag);
                 /* FIXME: (reg4a & a_speed) ? */