dmaengine: dw: dmamux: Fix device reference leak in rzn1_dmamux_route_allocate

The reference taken by of_find_device_by_node()
must be released when not needed anymore.
Add missing put_device() call to fix device reference leaks.

Fixes: 134d9c52fca2 ("dmaengine: dw: dmamux: Introduce RZN1 DMA router support")
Cc: stable@vger.kernel.org
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20250902090358.2423285-1-linmq006@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
diff --git a/drivers/dma/dw/rzn1-dmamux.c b/drivers/dma/dw/rzn1-dmamux.c
index 4fb8508..deadf13 100644
--- a/drivers/dma/dw/rzn1-dmamux.c
+++ b/drivers/dma/dw/rzn1-dmamux.c
@@ -48,12 +48,16 @@ static void *rzn1_dmamux_route_allocate(struct of_phandle_args *dma_spec,
 	u32 mask;
 	int ret;
 
-	if (dma_spec->args_count != RNZ1_DMAMUX_NCELLS)
-		return ERR_PTR(-EINVAL);
+	if (dma_spec->args_count != RNZ1_DMAMUX_NCELLS) {
+		ret = -EINVAL;
+		goto put_device;
+	}
 
 	map = kzalloc(sizeof(*map), GFP_KERNEL);
-	if (!map)
-		return ERR_PTR(-ENOMEM);
+	if (!map) {
+		ret = -ENOMEM;
+		goto put_device;
+	}
 
 	chan = dma_spec->args[0];
 	map->req_idx = dma_spec->args[4];
@@ -94,12 +98,15 @@ static void *rzn1_dmamux_route_allocate(struct of_phandle_args *dma_spec,
 	if (ret)
 		goto clear_bitmap;
 
+	put_device(&pdev->dev);
 	return map;
 
 clear_bitmap:
 	clear_bit(map->req_idx, dmamux->used_chans);
 free_map:
 	kfree(map);
+put_device:
+	put_device(&pdev->dev);
 
 	return ERR_PTR(ret);
 }