Now that we have the DT validation in place, let's convert the device tree
bindings for the Amlogic MHU controller over to a YAML schemas.

Signed-off-by: Neil Armstrong <redacted>
---
 .../mailbox/amlogic,meson-gxbb-mhu.yaml       | 53 +++++++++++++++++++
 .../devicetree/bindings/mailbox/meson-mhu.txt | 34 ------------
 2 files changed, 53 insertions(+), 34 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/mailbox/amlogic,meson-gxbb-mhu.yaml
 delete mode 100644 Documentation/devicetree/bindings/mailbox/meson-mhu.txt

diff --git a/Documentation/devicetree/bindings/mailbox/amlogic,meson-gxbb-mhu.yaml b/Documentation/devicetree/bindings/mailbox/amlogic,meson-gxbb-mhu.yaml
new file mode 100644
index 000000000000..2536a0082cff
--- /dev/null
+++ b/Documentation/devicetree/bindings/mailbox/amlogic,meson-gxbb-mhu.yaml

@@ -0,0 +1,53 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+# Copyright 2019 BayLibre, SAS
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/mailbox/amlogic,meson-gxbb-mhu.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Amlogic Meson Message-Handling-Unit Controller
+
+maintainers:
+  - Neil Armstrong <narmstrong@baylibre.com>
+
+description: |
+  The Amlogic's Meson SoCs Message-Handling-Unit (MHU) is a mailbox controller
+  that has 3 independent channels/links to communicate with remote processor(s).
+  MHU links are hardwired on a platform. A link raises interrupt for any
+  received data. However, there is no specified way of knowing if the sent
+  data has been read by the remote. This driver assumes the sender polls
+  STAT register and the remote clears it after having read the data.
+
+properties:
+  compatible:
+    enum:
+      - amlogic,meson-gxbb-mhu
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    minItems: 3
+    maxItems: 3