ide: add missing validity checks for identify words 62 and 63

Check validity of identify words 62 and 63 before using them 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 de33e6f88f171d57433cf732d0e9be53c008cbf2..ada2a3ea943006e1e64a3bb596d6d07645de1c4c 100644 (file)
--- a/drivers/ide/ide-dma.c
+++ b/drivers/ide/ide-dma.c
@@ -731,10 +731,12 @@ static unsigned int ide_get_mode_mask(ide_drive_t *drive, u8 base)
                        mask &= 0x07;
                break;
        case XFER_MW_DMA_0:
-               mask = id->dma_mword & hwif->mwdma_mask;
+               if (id->field_valid & 2)
+                       mask = id->dma_mword & hwif->mwdma_mask;
                break;
        case XFER_SW_DMA_0:
-               mask = id->dma_1word & hwif->swdma_mask;
+               if (id->field_valid & 2)
+                       mask = id->dma_1word & hwif->swdma_mask;
                break;
        default:
                BUG();