dt-binding: spi: Document Macronix controller bindings

Document the bindings used by the Macronix controller.

Signed-off-by: Mason Yang <masonccyang@mxic.com.tw>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/Documentation/devicetree/bindings/spi/spi-mxic.txt b/Documentation/devicetree/bindings/spi/spi-mxic.txt
new file mode 100644 (file)
index 0000000..529f2da
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/spi-mxic.txt
@@ -0,0 +1,34 @@
+Macronix SPI controller Device Tree Bindings
+--------------------------------------------
+
+Required properties:
+- compatible: should be "mxicy,mx25f0a-spi"
+- #address-cells: should be 1
+- #size-cells: should be 0
+- reg: should contain 2 entries, one for the registers and one for the direct
+       mapping area
+- reg-names: should contain "regs" and "dirmap"
+- interrupts: interrupt line connected to the SPI controller
+- clock-names: should contain "ps_clk", "send_clk" and "send_dly_clk"
+- clocks: should contain 3 entries for the "ps_clk", "send_clk" and
+         "send_dly_clk" clocks
+
+Example:
+
+       spi@43c30000 {
+               compatible = "mxicy,mx25f0a-spi";
+               reg = <0x43c30000 0x10000>, <0xa0000000 0x20000000>;
+               reg-names = "regs", "dirmap";
+               clocks = <&clkwizard 0>, <&clkwizard 1>, <&clkc 18>;
+               clock-names = "send_clk", "send_dly_clk", "ps_clk";
+               #address-cells = <1>;
+               #size-cells = <0>;
+
+               flash@0 {
+                       compatible = "jedec,spi-nor";
+                       reg = <0>;
+                       spi-max-frequency = <25000000>;
+                       spi-tx-bus-width = <4>;
+                       spi-rx-bus-width = <4>;
+               };
+       };