dm: core: Allow uclass to set up a device's child after it is probed

Some buses need to set up their child devices after they are probed.
Support a common child_post_probe() method for the uclass.

With this change, the two APIs uclass_pre_probe_device() and
uclass_post_probe_device() become symmetric.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

drivers/core/uclass.c

@@ -687,8 +687,19 @@ int uclass_pre_probe_device(struct udevice *dev)
 
 int uclass_post_probe_device(struct udevice *dev)
 {
-	struct uclass_driver *uc_drv = dev->uclass->uc_drv;
+	struct uclass_driver *uc_drv;
+	int ret;
+
+	if (dev->parent) {
+		uc_drv = dev->parent->uclass->uc_drv;
+		if (uc_drv->child_post_probe) {
+			ret = uc_drv->child_post_probe(dev);
+			if (ret)
+				return ret;
+		}
+	}
 
+	uc_drv = dev->uclass->uc_drv;
 	if (uc_drv->post_probe)
 		return uc_drv->post_probe(dev);
 

include/dm/uclass.h

@@ -61,7 +61,8 @@ struct udevice;
  * @post_probe: Called after a new device is probed
  * @pre_remove: Called before a device is removed
  * @child_post_bind: Called after a child is bound to a device in this uclass
- * @child_pre_probe: Called before a child is probed in this uclass
+ * @child_pre_probe: Called before a child in this uclass is probed
+ * @child_post_probe: Called after a child in this uclass is probed
  * @init: Called to set up the uclass
  * @destroy: Called to destroy the uclass
  * @priv_auto_alloc_size: If non-zero this is the size of the private data
@@ -94,6 +95,7 @@ struct uclass_driver {
 	int (*pre_remove)(struct udevice *dev);
 	int (*child_post_bind)(struct udevice *dev);
 	int (*child_pre_probe)(struct udevice *dev);
+	int (*child_post_probe)(struct udevice *dev);
 	int (*init)(struct uclass *class);
 	int (*destroy)(struct uclass *class);
 	int priv_auto_alloc_size;