Add bindings for the Tegra Combined UART device used to talk to the
UART console on Tegra194 systems.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
---
  .../bindings/serial/nvidia,tegra194-tcu.txt        | 35 ++++++++++++++++++++++
  1 file changed, 35 insertions(+)
  create mode 100644 Documentation/devicetree/bindings/serial/nvidia,tegra194-tcu.txt

diff --git a/Documentation/devicetree/bindings/serial/nvidia,tegra194-tcu.txt b/Documentation/devicetree/bindings/serial/nvidia,tegra194-tcu.txt
new file mode 100644
index 000000000000..86763bc5d74f
--- /dev/null
+++ b/Documentation/devicetree/bindings/serial/nvidia,tegra194-tcu.txt

@@ -0,0 +1,35 @@
+NVIDIA Tegra Combined UART (TCU)
+
+The TCU is a system for sharing a hardware UART instance among multiple
+systems withing the Tegra SoC. It is implemented through a mailbox-
+based protocol where each "virtual UART" has a pair of mailboxes, one
+for transmitting and one for receiving, that is used to communicate
+with the hardware implementing the TCU.
+
+Required properties:
+- name : Should be tcu
+- compatible
+    Array of strings
+    One of:
+    - "nvidia,tegra194-tcu"