[PATCH] dmaengine: imx-dma: Disable use of hw_chain to fix sg_dma transfers.

From: Javier Martin
Date: Tue Oct 30 2012 - 11:58:53 EST


HW chaining is currently broken in imx-dma. It can be easily reproduced doing
intensive accesses to a external MMC card and checking how the file system
is corrupted.

Preventing the driver to use HW chaining solves these issues.


Signed-off-by: Javier Martin <javier.martin@xxxxxxxxxxxxxxxxx>
---
drivers/dma/imx-dma.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/dma/imx-dma.c b/drivers/dma/imx-dma.c
index 5084975..03f3b64 100644
--- a/drivers/dma/imx-dma.c
+++ b/drivers/dma/imx-dma.c
@@ -643,9 +643,8 @@ static int imxdma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
break;
}

- imxdmac->hw_chaining = 1;
- if (!imxdma_hw_chain(imxdmac))
- return -EINVAL;
+ imxdmac->hw_chaining = 0;
+
imxdmac->ccr_from_device = (mode | IMX_DMA_TYPE_FIFO) |
((IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR) << 2) |
CCR_REN;
--
1.7.9.5

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