ide: fix pre-EIDE SWDMA support

If the word 62 is not defined use the word 52 to get SWDMA mask
in ide_get_mode_mask().

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

diff --git a/drivers/ide/ide-dma.c b/drivers/ide/ide-dma.c
index 85db8e8..e8c6e1e 100644 (file)
--- a/drivers/ide/ide-dma.c
+++ b/drivers/ide/ide-dma.c
@@ -702,8 +702,22 @@ static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base)
                        mask = id->dma_mword & hwif->mwdma_mask;
                break;
        case XFER_SW_DMA_0:
-               if (id->field_valid & 2)
+               if (id->field_valid & 2) {
                        mask = id->dma_1word & hwif->swdma_mask;
+               } else if (id->tDMA) {
+                       /*
+                        * ide_fix_driveid() doesn't convert ->tDMA to the
+                        * CPU endianness so we need to do it here
+                        */
+                       u8 mode = le16_to_cpu(id->tDMA);
+
+                       /*
+                        * if the mode is valid convert it to the mask
+                        * (the maximum allowed mode is XFER_SW_DMA_2)
+                        */
+                       if (mode <= 2)
+                               mask = ((2 << mode) - 1) & hwif->swdma_mask;
+               }
                break;
        default:
                BUG();