dmaengine: xilinx_dma: Correctly handle cyclic descriptor callbacks

DMA clients can provide one of two types of callbacks. For this reason
dmaengine drivers should not directly invoke `callback`, but always use
`dmaengine_desc_callback_invoke()`. This makes sure that both types of
callbacks are handled correctly.

The xilinx_dma driver currently doesn't do this for cyclic descriptors and
only handles the `callback` type callback. If the client used the
`callback_result` type callback it will not be called.

Fix this by switching to `dmaengine_desc_callback_valid()` and
`dmaengine_desc_callback_invoke()`.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20211025075428.2094-2-lars@metafoo.deSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/xilinx/xilinx_dma.c

@@ -998,14 +998,12 @@ static void xilinx_dma_chan_handle_cyclic(struct xilinx_dma_chan *chan,
 					  struct xilinx_dma_tx_descriptor *desc,
 					  unsigned long *flags)
 {
-	dma_async_tx_callback callback;
-	void *callback_param;
+	struct dmaengine_desc_callback cb;
 
-	callback = desc->async_tx.callback;
-	callback_param = desc->async_tx.callback_param;
-	if (callback) {
+	dmaengine_desc_get_callback(&desc->async_tx, &cb);
+	if (dmaengine_desc_callback_valid(&cb)) {
 		spin_unlock_irqrestore(&chan->lock, *flags);
-		callback(callback_param);
+		dmaengine_desc_callback_invoke(&cb, NULL);
 		spin_lock_irqsave(&chan->lock, *flags);
 	}
 }