dmaengine: add support to provide error result from a DMA transation

Adding a new callback that will provide the error result for a transaction.
The result is allocated on the stack and the callback should create a copy
if it wishes to retain the information after exiting. The result parameter
is now defined and takes over the dummy void pointer we placed in the
helper functions previously. dmaengine drivers should start converting
to the new "callback_result" callback in order to receive transaction
results.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 30de0197263a..cc535a478bae 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -441,6 +441,21 @@ typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param);
 
 typedef void (*dma_async_tx_callback)(void *dma_async_param);
 
+enum dmaengine_tx_result {
+	DMA_TRANS_NOERROR = 0,		/* SUCCESS */
+	DMA_TRANS_READ_FAILED,		/* Source DMA read failed */
+	DMA_TRANS_WRITE_FAILED,		/* Destination DMA write failed */
+	DMA_TRANS_ABORTED,		/* Op never submitted / aborted */
+};
+
+struct dmaengine_result {
+	enum dmaengine_tx_result result;
+	u32 residue;
+};
+
+typedef void (*dma_async_tx_callback_result)(void *dma_async_param,
+				const struct dmaengine_result *result);
+
 struct dmaengine_unmap_data {
 	u8 map_cnt;
 	u8 to_cnt;
@@ -478,6 +493,7 @@ struct dma_async_tx_descriptor {
 	dma_cookie_t (*tx_submit)(struct dma_async_tx_descriptor *tx);
 	int (*desc_free)(struct dma_async_tx_descriptor *tx);
 	dma_async_tx_callback callback;
+	dma_async_tx_callback_result callback_result;
 	void *callback_param;
 	struct dmaengine_unmap_data *unmap;
 #ifdef CONFIG_ASYNC_TX_ENABLE_CHANNEL_SWITCH