dm: core: Allow the uclass to set up a device's child after binding

For buses, after a child is bound, allow the uclass to perform some
processing. This can be used to figure out the address of the child (e.g.
the chip select for SPI slaves) so that it is ready to be probed.

This avoids bus drivers having to repeat the same process, which really
should be done by the uclass, since it is common.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.m@jp.panasonic.com>

1 files changed, 16 insertions, 5 deletions

diff --git a/drivers/core/uclass.c b/drivers/core/uclass.c
index 901b06ed2b..a5445518f5 100644
--- a/drivers/core/uclass.c
+++ b/drivers/core/uclass.c
@@ -319,18 +319,29 @@ int uclass_bind_device(struct udevice *dev)
 	int ret;
 
 	uc = dev->uclass;
-
 	list_add_tail(&dev->uclass_node, &uc->dev_head);
 
+	if (dev->parent) {
+		struct uclass_driver *uc_drv = dev->parent->uclass->uc_drv;
+
+		if (uc_drv->child_post_bind) {
+			ret = uc_drv->child_post_bind(dev);
+			if (ret)
+				goto err;
+		}
+	}
 	if (uc->uc_drv->post_bind) {
 		ret = uc->uc_drv->post_bind(dev);
-		if (ret) {
-			list_del(&dev->uclass_node);
-			return ret;
-		}
+		if (ret)
+			goto err;
 	}
 
 	return 0;
+err:
+	/* There is no need to undo the parent's post_bind call */
+	list_del(&dev->uclass_node);
+
+	return ret;
 }
 
 int uclass_unbind_device(struct udevice *dev)