diff options
| author | Alan Cox <alan@redhat.com> | 2008-08-01 12:18:34 +0400 |
|---|---|---|
| committer | Jeff Garzik <jgarzik@redhat.com> | 2008-08-22 10:27:49 +0400 |
| commit | b15b3ebae102f89c25ccbcae0b2099af312f2e82 (patch) | |
| tree | 73f64d0e578d1c6bc6a3dc43f940a31f24daad8f /drivers/ata/pata_sc1200.c | |
| parent | 20e2de4a505aa02131a95665e8920eb053fce686 (diff) | |
| download | linux-b15b3ebae102f89c25ccbcae0b2099af312f2e82.tar.xz | |
libata: Fix a large collection of DMA mode mismatches
Dave Müller sent a diff for the pata_oldpiix that highlighted a problem
where a lot of the ATA drivers assume dma_mode == 0 means "no DMA" while
the core code uses 0xFF.
This turns out to have other consequences such as code doing >= XFER_UDMA_0
also catching 0xFF as UDMAlots. Fortunately it doesn't generally affect
set_dma_mode, although some drivers call back into their own set mode code
from other points.
Having been through the drivers I've added helpers for using_udma/using_mwdma
dma_enabled so that people don't open code ranges that may change (eg if UDMA8
appears somewhere)
Thanks to David for the initial bits
[and added fix for pata_oldpiix from and signed-off-by Dave Mueller
<dave.mueller@gmx.ch> -jg]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Diffstat (limited to 'drivers/ata/pata_sc1200.c')
| -rw-r--r-- | drivers/ata/pata_sc1200.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/ata/pata_sc1200.c b/drivers/ata/pata_sc1200.c index cbab397e3db7..0278fd2b8fb1 100644 --- a/drivers/ata/pata_sc1200.c +++ b/drivers/ata/pata_sc1200.c @@ -167,10 +167,10 @@ static unsigned int sc1200_qc_issue(struct ata_queued_cmd *qc) struct ata_device *prev = ap->private_data; /* See if the DMA settings could be wrong */ - if (adev->dma_mode != 0 && adev != prev && prev != NULL) { + if (ata_dma_enabled(adev) && adev != prev && prev != NULL) { /* Maybe, but do the channels match MWDMA/UDMA ? */ - if ((adev->dma_mode >= XFER_UDMA_0 && prev->dma_mode < XFER_UDMA_0) || - (adev->dma_mode < XFER_UDMA_0 && prev->dma_mode >= XFER_UDMA_0)) + if ((ata_using_udma(adev) && !ata_using_udma(prev)) || + (ata_using_udma(prev) && !ata_using_udma(adev))) /* Switch the mode bits */ sc1200_set_dmamode(ap, adev); } |