[PATCH v2 1/3] dmaengine: k3dma: fix non-cyclic mode

From: Antonio Borneo
Date: Tue Aug 01 2017 - 16:10:48 EST

Commit 36387a2b1f62b5c087c5fe6f0f7b23b94f722ad7 ("k3dma: Fix
memory handling in preparation for cyclic mode") broke the
logic around ds_run/ds_done in case of non-cyclic DMA.

This went unnoticed as the only user of k3dma was the i2s
audio driver but, with a patch set to enable dma on SPI, the
issue popped out.

The fix re-applies the initialization to ds_run/ds_done in
k3_dma_start_txd() that were removed by the commit above.

Also, one of the calls to k3_dma_start_txd() is triggered by
(ds_done != NULL), so remove the noisy and useless call to

Signed-off-by: Antonio Borneo <borneo.antonio@xxxxxxxxx>
To: dmaengine@xxxxxxxxxxxxxxx
To: Vinod Koul <vinod.koul@xxxxxxxxx>
To: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: John Stultz <john.stultz@xxxxxxxxxx>
Cc: Zhangfei Gao <zhangfei.gao@xxxxxxxxxx>
drivers/dma/k3dma.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/k3dma.c b/drivers/dma/k3dma.c
index 01e25c6..c00eb12 100644
--- a/drivers/dma/k3dma.c
+++ b/drivers/dma/k3dma.c
@@ -275,12 +275,14 @@ static int k3_dma_start_txd(struct k3_dma_chan *c)

- WARN_ON_ONCE(c->phy->ds_done);
c->phy->ds_run = ds;
+ c->phy->ds_done = NULL;
/* start dma */
k3_dma_set_desc(c->phy, &ds->desc_hw[0]);
return 0;
+ c->phy->ds_run = NULL;
+ c->phy->ds_done = NULL;
return -EAGAIN;