From b15b3ebae102f89c25ccbcae0b2099af312f2e82 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Fri, 1 Aug 2008 09:18:34 +0100 Subject: libata: Fix a large collection of DMA mode mismatches MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 -jg] Signed-off-by: Alan Cox Signed-off-by: Jeff Garzik --- include/linux/libata.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'include') diff --git a/include/linux/libata.h b/include/linux/libata.h index 80233fdc159..225bfc5bd9e 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 -- cgit v1.2.3