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 /include | |
| 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 'include')
| -rw-r--r-- | include/linux/libata.h | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/include/linux/libata.h b/include/linux/libata.h index 80233fdc159f..225bfc5bd9ec 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -1429,6 +1429,28 @@ static inline unsigned long ata_deadline(unsigned long from_jiffies, return from_jiffies + msecs_to_jiffies(timeout_msecs); } +/* Don't open code these in drivers as there are traps. Firstly the range may + change in future hardware and specs, secondly 0xFF means 'no DMA' but is + > UDMA_0. Dyma ddreigiau */ + +static inline int ata_using_mwdma(struct ata_device *adev) +{ + if (adev->dma_mode >= XFER_MW_DMA_0 && adev->dma_mode <= XFER_MW_DMA_4) + return 1; + return 0; +} + +static inline int ata_using_udma(struct ata_device *adev) +{ + if (adev->dma_mode >= XFER_UDMA_0 && adev->dma_mode <= XFER_UDMA_7) + return 1; + return 0; +} + +static inline int ata_dma_enabled(struct ata_device *adev) +{ + return (adev->dma_mode == 0xFF ? 0 : 1); +} /************************************************************************** * PMP - drivers/ata/libata-pmp.c |