staging: vchiq_arm: Give vchiq children DT nodes

raspberrypi inclusion
category: feature
bugzilla: 50432

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

vchiq kernel clients are now instantiated as platform drivers rather
than using DT, but the children of the vchiq interface may still
benefit from access to DT properties. Give them the option of a
a sub-node of the vchiq parent for configuration and to allow
them to be disabled.
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

@@ -2703,12 +2703,20 @@ vchiq_register_child(struct platform_device *pdev, const char *name)
 	pdevinfo.id = PLATFORM_DEVID_NONE;
 	pdevinfo.dma_mask = DMA_BIT_MASK(32);
 
+	np = of_get_child_by_name(pdev->dev.of_node, name);
+
+	/* Skip the child if it is explicitly disabled */
+	if (np && !of_device_is_available(np))
+		return NULL;
+
 	child = platform_device_register_full(&pdevinfo);
 	if (IS_ERR(child)) {
 		dev_warn(&pdev->dev, "%s not registered\n", name);
 		child = NULL;
 	}
 
+	child->dev.of_node = np;
+
 	/*
 	 * We want the dma-ranges etc to be copied from a device with the
 	 * correct dma-ranges for the VPU.