staging: vchiq_arm: children inherit DMA config

raspberrypi inclusion
category: feature
bugzilla: 50432

--------------------------------

Although it is no longer necessary for vchiq's children to have a
different DMA configuration to the parent, they do still need to
explicitly to have their DMA configuration set - to be that of the
parent.
Signed-off-by: NPhil Elwell <phil@raspberrypi.com>
Signed-off-by: NFang Yafen <yafen@iscas.ac.cn>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c

@@ -2718,8 +2718,18 @@ vchiq_register_child(struct platform_device *pdev, const char *name)
 
 	child->dev.of_node = np;
 
+	/*
+	 * We want the dma-ranges etc to be copied from the parent VCHIQ device
+	 * to be passed on to the children without a node of their own.
+	 */
+	if (!np)
+		np = pdev->dev.of_node;
+
 	of_dma_configure(&child->dev, np, true);
 
+	if (np != pdev->dev.of_node)
+		of_node_put(np);
+
 	return child;
 }