[PATCH] dma: imx-sdma: Save imx_dma_data into sdmac

From: Nicolin Chen
Date: Sun Jun 15 2014 - 23:30:38 EST


The filter() function is currently called by xlate() while it transfers
imx_dma_data as a local variable to the filter() but releases the data
right after returning a DMA channel pointer, which results chan->private
pointing an invalid memory space.

So this patch just stores the imx_dma_data into sdmac to make usre the
private pointer valid as long as the channel exists.

Signed-off-by: Nicolin Chen <nicoleotsuka@xxxxxxxxx>
---
drivers/dma/imx-sdma.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index 19041ce..fc04add 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -270,6 +270,7 @@ struct sdma_channel {
unsigned int chn_count;
unsigned int chn_real_count;
struct tasklet_struct tasklet;
+ struct imx_dma_data data;
};

#define IMX_DMA_SG_LOOP BIT(0)
@@ -1402,12 +1403,14 @@ err_dma_alloc:

static bool sdma_filter_fn(struct dma_chan *chan, void *fn_param)
{
+ struct sdma_channel *sdmac = to_sdma_chan(chan);
struct imx_dma_data *data = fn_param;

if (!imx_dma_is_general_purpose(chan))
return false;

- chan->private = data;
+ sdmac->data = *data;
+ chan->private = &sdmac->data;

return true;
}
--
1.8.4

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