diff options
Diffstat (limited to 'drivers/ide/pci/piix.c')
| -rw-r--r-- | drivers/ide/pci/piix.c | 17 |
1 files changed, 4 insertions, 13 deletions
diff --git a/drivers/ide/pci/piix.c b/drivers/ide/pci/piix.c index 27781d294cea..bd6d3f77d30c 100644 --- a/drivers/ide/pci/piix.c +++ b/drivers/ide/pci/piix.c @@ -203,20 +203,11 @@ static void piix_set_dma_mode(ide_drive_t *drive, const u8 speed) pci_read_config_byte(dev, 0x54, ®54); pci_read_config_byte(dev, 0x55, ®55); - switch(speed) { - case XFER_UDMA_4: - case XFER_UDMA_2: u_speed = 2 << (drive->dn * 4); break; - case XFER_UDMA_5: - case XFER_UDMA_3: - 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) { + u8 udma = speed - XFER_UDMA_0; + + u_speed = min_t(u8, 2 - (udma & 1), udma) << (drive->dn * 4); + if (!(reg48 & u_flag)) pci_write_config_byte(dev, 0x48, reg48 | u_flag); if (speed == XFER_UDMA_5) { |