Add documentation of device tree bindings for STM32 SPI/I2S.
Signed-off-by: olivier moysan <[email protected]>
---
.../devicetree/bindings/sound/st,stm32-i2s.txt | 68 ++++++++++++++++++++++
1 file changed, 68 insertions(+)
create mode 100644 Documentation/devicetree/bindings/sound/st,stm32-i2s.txt
diff --git a/Documentation/devicetree/bindings/sound/st,stm32-i2s.txt
b/Documentation/devicetree/bindings/sound/st,stm32-i2s.txt
new file mode 100644
index 0000000..67b854a
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/st,stm32-i2s.txt
@@ -0,0 +1,68 @@
+STMicroelectronics STM32 SPI/I2S Controller
+
+The SPI/I2S block supports I2S/PCM protocols when configured on I2S mode.
+Only some SPI instances support I2S.
+
+Required properties:
+ - compatible: Must be "st,stm32h7-i2s"
+ - reg: Offset and length of the device's register set.
+ - interrupts: Must contain the interrupt line id.
+ - clocks: Must contain phandle and clock specifier pairs for each entry
+ in clock-names.
+ - clock-names: Must contain "i2sclk", "pclk", "x8k" and "x11k".
+ "i2sclk": clock which feeds the internal clock generator
+ "pclk": clock which feeds the peripheral bus interface
+ "x8k": I2S parent clock for sampling rates multiple of 8kHz.
+ "x11k": I2S parent clock for sampling rates multiple of 11.025kHz.
+ - dmas: DMA specifiers for tx and rx dma.
+ See Documentation/devicetree/bindings/dma/stm32-dma.txt.
+ - dma-names: Identifier for each DMA request line. Must be "tx" and "rx".
+ - pinctrl-names: should contain only value "default"
+ - pinctrl-0: see Documentation/devicetree/bindings/pinctrl/pinctrl-stm32.txt
+
+Optional properties:
+ - resets: Reference to a reset controller asserting the reset controller
+
+The device node should contain one 'port' child node with one child 'endpoint'
+node, according to the bindings defined in Documentation/devicetree/bindings/
+graph.txt.
+
+Example:
+sound_card {
+ compatible = "audio-graph-card";
+ dais = <&i2s2_port 0>;
+};
+
+i2s2: audio-controller@40003800 {
+ compatible = "st,stm32h7-i2s";
+ #sound-dai-cells = <0>;
+ reg = <0x40003800 0x400>;
+ interrupts = <36>;
+ clocks = <&rcc PCLK1>, <&rcc SPI2_CK>, <&rcc PLL1_Q>, <&rcc PLL2_P>;
+ clock-names = "pclk", "i2sclk", "x8k", "x11k";
+ dmas = <&dmamux2 2 39 0x400 0x1>,
+ <&dmamux2 3 40 0x400 0x1>;
+ dma-names = "rx", "tx";
+ pinctrl-names = "default";
+ pinctrl-0 = <&pinctrl_i2s2>;
+
+ i2s2_port: port@0 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu_endpoint: endpoint {
+ remote-endpoint = <&codec_endpoint>;
+ format = "i2s";
+ bitclock-master = <&codec_endpoint>;
+ frame-master = <&codec_endpoint>;
+ };
+ };
+};
+
+audio-codec {
+ codec_port: port@0 {
+ codec_endpoint: endpoint {
+ remote-endpoint = <&cpu_endpoint>;
+ };
+ };
+};
--
1.9.1
