[PATCH 6/6] doc: dt: Document the target root overlay method
From: Pantelis Antoniou
Date: Mon May 09 2016 - 14:06:31 EST
Add a description of the target root overlay method to the overlay
documention file.
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@xxxxxxxxxxxx>
---
Documentation/devicetree/overlay-notes.txt | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/Documentation/devicetree/overlay-notes.txt b/Documentation/devicetree/overlay-notes.txt
index dd595e6..00ede57 100644
--- a/Documentation/devicetree/overlay-notes.txt
+++ b/Documentation/devicetree/overlay-notes.txt
@@ -104,6 +104,10 @@ If your board has multiple slots/places where a single overlay can work
and each slot is defined by a node, you can use the of_overlay_create_indirect()
method to select the target.
+For overlays on probeable busses, use the of_overlay_create_target_root() method
+in which you supply a device node as a target root, and which all target
+references in the overlay are performed relative to that node.
+
Overlay DTS Format
------------------
@@ -144,3 +148,7 @@ contains the information required to map from a phandle to a tree location.
The indirect target requires the use of a selector target on the call to
of_overlay_create_indirect(). I.e. passing the "foo" id will select the target
in the foo node, "bar" in bar node, etc.
+
+Note that when using the target root create method all target references must
+lie under the target root node. I.e. the overlay is not allowed to 'break' out
+of the root.
--
1.7.12