Iff bmdma_setup() has to stop a DMA transfer before starting a new one, then the STOP bit in the ATAPI_CONTROL1 register will remain set (it's only cleared when setting the START bit to 1) and then bmdma_start() method will set both START and STOP bits simultaneously which should abort the transfer being just started. Avoid that by explicitly clearing the STOP bit in bmdma_start() method (in this case it will be ignored on write). Signed-off-by: Sergei Shtylyov <sergei.shtylyov@xxxxxxxxxxxxxxxxxx> --- This patch is against 'for-3.10-fixes' branch of Tejun Heo's 'libata.git' repo. drivers/ata/sata_rcar.c | 1 + 1 file changed, 1 insertion(+) Index: libata/drivers/ata/sata_rcar.c =================================================================== --- libata.orig/drivers/ata/sata_rcar.c +++ libata/drivers/ata/sata_rcar.c @@ -549,6 +549,7 @@ static void sata_rcar_bmdma_start(struct /* start host DMA transaction */ dmactl = ioread32(priv->base + ATAPI_CONTROL1_REG); + dmactl &= ~ATAPI_CONTROL1_STOP; dmactl |= ATAPI_CONTROL1_START; iowrite32(dmactl, priv->base + ATAPI_CONTROL1_REG); } -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html