@@ -170,7 +170,7 @@ static void vchan_free_desc(struct virt_dma_desc *vdesc)
dw_edma_free_desc(vd2dw_edma_desc(vdesc));
}
-static void dw_edma_start_transfer(struct dw_edma_chan *chan)
+static int dw_edma_start_transfer(struct dw_edma_chan *chan)
{
struct dw_edma_chunk *child;
struct dw_edma_desc *desc;
@@ -178,16 +178,16 @@ static void dw_edma_start_transfer(struct dw_edma_chan *chan)
vd = vchan_next_desc(&chan->vc);
if (!vd)
- return;
+ return 0;
desc = vd2dw_edma_desc(vd);
if (!desc)
- return;
+ return 0;
child = list_first_entry_or_null(&desc->chunk->list,
struct dw_edma_chunk, list);
if (!child)
- return;
+ return 0;
dw_edma_v0_core_start(child, !desc->xfer_sz);
desc->xfer_sz += child->ll_region.sz;
@@ -195,6 +195,8 @@ static void dw_edma_start_transfer(struct dw_edma_chan *chan)
list_del(&child->list);
kfree(child);
desc->chunks_alloc--;
+
+ return 1;
}
static int dw_edma_device_config(struct dma_chan *dchan,
@@ -568,14 +570,17 @@ static void dw_edma_done_interrupt(struct dw_edma_chan *chan)
switch (chan->request) {
case EDMA_REQ_NONE:
desc = vd2dw_edma_desc(vd);
- if (desc->chunks_alloc) {
- chan->status = EDMA_ST_BUSY;
- dw_edma_start_transfer(chan);
- } else {
+ if (!desc->chunks_alloc) {
list_del(&vd->node);
vchan_cookie_complete(vd);
- chan->status = EDMA_ST_IDLE;
}
+
+ /* Continue to transfer in case of there are rest chunks, or issued
+ * requests remain.
+ */
+ chan->status = EDMA_ST_BUSY;
+ if (!dw_edma_start_transfer(chan))
+ chan->status = EDMA_ST_IDLE;
break;
case EDMA_REQ_STOP:
The dw-edma driver stops after processing a DMA request even if a request remains in the issued queue, which is not the expected behavior. The DMA engine API requires continuous processing. Fix it to add a trigger to start after one processing finished if there are requests remain. Fixes: e63d79d1ffcd ("dmaengine: Add Synopsys eDMA IP core driver") Signed-off-by: Shunsuke Mie <mie@igel.co.jp> --- drivers/dma/dw-edma/dw-edma-core.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-)