This patch adds a DT binding documentation for the MT2712 soc.

Signed-off-by: Leilk Liu <redacted>
---
 .../devicetree/bindings/spi/spi-slave-mt27xx.txt   |   32 ++++++++++++++++++++
 1 file changed, 32 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/spi/spi-slave-mt27xx.txt

diff --git a/Documentation/devicetree/bindings/spi/spi-slave-mt27xx.txt b/Documentation/devicetree/bindings/spi/spi-slave-mt27xx.txt
new file mode 100644
index 0000000..09cb2c4
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/spi-slave-mt27xx.txt

@@ -0,0 +1,32 @@
+Binding for MTK SPI Slave controller
+
+Required properties:
+- compatible: should be one of the following.
+    - mediatek,mt2712-spi-slave: for mt2712 platforms
+- reg: Address and length of the register set for the device.
+- interrupts: Should contain spi interrupt.
+- clocks: phandles to input clocks.
+  It's clock gate, and should be <&infracfg CLK_INFRA_AO_SPI1>.
+- clock-names: should be "spi" for the clock gate.
+
+Optional properties:
+- assigned-clocks: it's mux clock, should be <&topckgen CLK_TOP_SPISLV_SEL>.
+- assigned-clock-parents: parent of mux clock.
+  It's PLL, and should be on of the following.