[PATCH] dmaengine: imx-sdma: Report a DMA_ERROR in status if 'count' or 'dma_address' do not match DMA_SLAVE_BUSWIDTH

From: Christophe JAILLET
Date: Sun Sep 24 2017 - 02:28:46 EST


All sanity checks in this function set 'sdmac->status = DMA_ERROR' if
something looks wrong, except if the byte count or the address don't match
the bus width.

Fix it and report the error in status in such a case.

Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
---
Untested, so please review carefuly.
---
drivers/dma/imx-sdma.c | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index a67ec1bdc4e0..f0419967eb92 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -1240,26 +1240,31 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
sdmac->chn_count += count;

if (sdmac->word_size > DMA_SLAVE_BUSWIDTH_4_BYTES) {
- ret = -EINVAL;
+ ret = -EINVAL;
goto err_out;
}

switch (sdmac->word_size) {
case DMA_SLAVE_BUSWIDTH_4_BYTES:
bd->mode.command = 0;
- if (count & 3 || sg->dma_address & 3)
- return NULL;
+ if (count & 3 || sg->dma_address & 3) {
+ ret = -EINVAL;
+ goto err_out;
+ }
break;
case DMA_SLAVE_BUSWIDTH_2_BYTES:
bd->mode.command = 2;
- if (count & 1 || sg->dma_address & 1)
- return NULL;
+ if (count & 1 || sg->dma_address & 1) {
+ ret = -EINVAL;
+ goto err_out;
+ }
break;
case DMA_SLAVE_BUSWIDTH_1_BYTE:
bd->mode.command = 1;
break;
default:
- return NULL;
+ ret = -EINVAL;
+ goto err_out;
}

param = BD_DONE | BD_EXTD | BD_CONT;
--
2.11.0