[PATCH] Allow to use DMA_CTRL_REUSE flag for all channel types

From: Eugeniy Paltsev
Date: Fri Apr 28 2017 - 09:38:01 EST


In the current implementation dma_get_slave_caps is used to check
state of descriptor_reuse option. But dma_get_slave_caps includes
check if the channel supports slave transactions.
So DMA_CTRL_REUSE flag can be set (even for MEM-TO-MEM tranfers)
only if channel supports slave transactions.

Now we can use DMA_CTRL_REUSE flag for all channel types.
Also it allows to test reusing mechanism with simply mem-to-mem dma
test.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx>
---
include/linux/dmaengine.h | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 5336808..92cf8b0 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -1376,11 +1376,7 @@ static inline int dma_get_slave_caps(struct dma_chan *chan,

static inline int dmaengine_desc_set_reuse(struct dma_async_tx_descriptor *tx)
{
- struct dma_slave_caps caps;
-
- dma_get_slave_caps(tx->chan, &caps);
-
- if (caps.descriptor_reuse) {
+ if (tx->chan->device->descriptor_reuse) {
tx->flags |= DMA_CTRL_REUSE;
return 0;
} else {
--
2.9.3