Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / Documentation / devicetree / bindings / spi / efm32-spi.txt

diff --git a/kernel/Documentation/devicetree/bindings/spi/efm32-spi.txt b/kernel/Documentation/devicetree/bindings/spi/efm32-spi.txt
new file mode 100644 (file)
index 0000000..750e29a
--- /dev/null
+++ b/kernel/Documentation/devicetree/bindings/spi/efm32-spi.txt
@@ -0,0 +1,41 @@
+* Energy Micro EFM32 SPI
+
+Required properties:
+- #address-cells: see spi-bus.txt
+- #size-cells: see spi-bus.txt
+- compatible: should be "energymicro,efm32-spi"
+- reg: Offset and length of the register set for the controller
+- interrupts: pair specifying rx and tx irq
+- clocks: phandle to the spi clock
+- cs-gpios: see spi-bus.txt
+
+Recommended properties :
+- energymicro,location: Value to write to the ROUTE register's LOCATION
+                        bitfield to configure the pinmux for the device, see
+                        datasheet for values.
+                        If this property is not provided, keeping what is
+                        already configured in the hardware, so its either the
+                        reset default 0 or whatever the bootloader did.
+
+Example:
+
+spi1: spi@0x4000c400 { /* USART1 */
+       #address-cells = <1>;
+       #size-cells = <0>;
+       compatible = "energymicro,efm32-spi";
+       reg = <0x4000c400 0x400>;
+       interrupts = <15 16>;
+       clocks = <&cmu 20>;
+       cs-gpios = <&gpio 51 1>; // D3
+       energymicro,location = <1>;
+       status = "ok";
+
+       ks8851@0 {
+               compatible = "ks8851";
+               spi-max-frequency = <6000000>;
+               reg = <0>;
+               interrupt-parent = <&boardfpga>;
+               interrupts = <4>;
+               status = "ok";
+       };
+};