diff options
| -rw-r--r-- | drivers/ata/pata_via.c | 19 |
1 files changed, 13 insertions, 6 deletions
diff --git a/drivers/ata/pata_via.c b/drivers/ata/pata_via.c index 78eac276effb..0d97890af681 100644 --- a/drivers/ata/pata_via.c +++ b/drivers/ata/pata_via.c @@ -303,14 +303,21 @@ static void via_do_set_mode(struct ata_port *ap, struct ata_device *adev, int mo } /* Set UDMA unless device is not UDMA capable */ - if (udma_type && t.udma) { - u8 cable80_status; + if (udma_type) { + u8 udma_etc; - /* Get 80-wire cable detection bit */ - pci_read_config_byte(pdev, 0x50 + offset, &cable80_status); - cable80_status &= 0x10; + pci_read_config_byte(pdev, 0x50 + offset, &udma_etc); - pci_write_config_byte(pdev, 0x50 + offset, ut | cable80_status); + /* clear transfer mode bit */ + udma_etc &= ~0x20; + + if (t.udma) { + /* preserve 80-wire cable detection bit */ + udma_etc &= 0x10; + udma_etc |= ut; + } + + pci_write_config_byte(pdev, 0x50 + offset, udma_etc); } } |