Add compatible for Ambarella.

Signed-off-by: Li Chen <redacted>
Change-Id: I32513d98f52af0311dfb55dd5c4739a58f6b9fc1
---
 .../bindings/serial/ambarella_uart.yaml       | 57 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 58 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/serial/ambarella_uart.yaml

diff --git a/Documentation/devicetree/bindings/serial/ambarella_uart.yaml b/Documentation/devicetree/bindings/serial/ambarella_uart.yaml
new file mode 100644
index 000000000000..238d68078270
--- /dev/null
+++ b/Documentation/devicetree/bindings/serial/ambarella_uart.yaml

@@ -0,0 +1,57 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/serial/ambarella_uart.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Ambarella S6LM SoC UART Controller
+
+maintainers:
+  - Li Chen <lchen@ambarella.com>
+
+properties:
+  compatible:
+    const: ambarella,uart
+
+  reg:
+    maxItems: 1
+
+  amb,ignore-fe:
+    description: |
+      ignore frame error report for CV2/CV22/CV25/S6LM because it's
+      checked too strict so that normal stop may be treated as frame error.