dmaengine: jz4780: Ensure channel is on correct controller in filter

When scanning for a free DMA channel, the filter function should ensure
that the channel is on the controller that it was requested to be on in
the DT.

Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/dma-jz4780.c

@@ -145,7 +145,8 @@ struct jz4780_dma_dev {
 	struct jz4780_dma_chan chan[JZ_DMA_NR_CHANNELS];
 };
 
-struct jz4780_dma_data {
+struct jz4780_dma_filter_data {
+	struct device_node *of_node;
 	uint32_t transfer_type;
 	int channel;
 };
@@ -684,7 +685,10 @@ static bool jz4780_dma_filter_fn(struct dma_chan *chan, void *param)
 {
 	struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan);
 	struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan);
-	struct jz4780_dma_data *data = param;
+	struct jz4780_dma_filter_data *data = param;
+
+	if (jzdma->dma_device.dev->of_node != data->of_node)
+		return false;
 
 	if (data->channel > -1) {
 		if (data->channel != jzchan->id)
@@ -703,11 +707,12 @@ static struct dma_chan *jz4780_of_dma_xlate(struct of_phandle_args *dma_spec,
 {
 	struct jz4780_dma_dev *jzdma = ofdma->of_dma_data;
 	dma_cap_mask_t mask = jzdma->dma_device.cap_mask;
-	struct jz4780_dma_data data;
+	struct jz4780_dma_filter_data data;
 
 	if (dma_spec->args_count != 2)
 		return NULL;
 
+	data.of_node = ofdma->of_node;
 	data.transfer_type = dma_spec->args[0];
 	data.channel = dma_spec->args[1];