Re: [PATCH] dmaengine: imx-sdma: fix bug in buffer descriptorinitialization

[Sascha Hauer]

On Mon, Nov 22, 2010 at 06:35:18PM +0100, Anatolij Gustschin wrote:
> Currently while submitting scatterlists with more than one SG
> entry the DMA buffer address from the first SG entry is inserted
> into all initialized DMA buffer descriptors. This is due to the
> typo in the for_each_sg() loop where the scatterlist pointer is
> used for obtaining the DMA buffer address and _not_ the SG list
> iterator.
> 
> As a result all received data will be written only into the first
> DMA buffer while reading. While writing the data from the first
> DMA buffer is send to the device multiple times. This caused
> the filesystem destruction on the MMC card when using DMA in
> mxcmmc driver.
> 
> Signed-off-by: Anatolij Gustschin <agust@xxxxxxx>
> Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
> Cc: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>

Acked-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>

> ---
>  drivers/dma/imx-sdma.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
> index 0834323..13d6447 100644
> --- a/drivers/dma/imx-sdma.c
> +++ b/drivers/dma/imx-sdma.c
> @@ -951,7 +951,7 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
>  		struct sdma_buffer_descriptor *bd = &sdmac->bd[i];
>  		int param;
>  
> -		bd->buffer_addr = sgl->dma_address;
> +		bd->buffer_addr = sg->dma_address;
>  
>  		count = sg->length;
>  
> -- 
> 1.7.1
> 
> 

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