| STMicroelectronics STM32 Serial Audio Interface (SAI). |
| |
| The SAI interface (Serial Audio Interface) offers a wide set of audio protocols |
| as I2S standards, LSB or MSB-justified, PCM/DSP, TDM, and AC'97. |
| The SAI contains two independent audio sub-blocks. Each sub-block has |
| its own clock generator and I/O lines controller. |
| |
| Required properties: |
| - compatible: Should be "st,stm32f4-sai" |
| - reg: Base address and size of SAI common register set. |
| - clocks: Must contain phandle and clock specifier pairs for each entry |
| in clock-names. |
| - clock-names: Must contain "x8k" and "x11k" |
| "x8k": SAI parent clock for sampling rates multiple of 8kHz. |
| "x11k": SAI parent clock for sampling rates multiple of 11.025kHz. |
| - interrupts: cpu DAI interrupt line shared by SAI sub-blocks |
| |
| Optional properties: |
| - resets: Reference to a reset controller asserting the SAI |
| |
| SAI subnodes: |
| Two subnodes corresponding to SAI sub-block instances A et B can be defined. |
| Subnode can be omitted for unsused sub-block. |
| |
| SAI subnodes required properties: |
| - compatible: Should be "st,stm32-sai-sub-a" or "st,stm32-sai-sub-b" |
| for SAI sub-block A or B respectively. |
| - reg: Base address and size of SAI sub-block register set. |
| - clocks: Must contain one phandle and clock specifier pair |
| for sai_ck which feeds the internal clock generator. |
| - clock-names: Must contain "sai_ck". |
| - dmas: see Documentation/devicetree/bindings/dma/stm32-dma.txt |
| - dma-names: identifier string for each DMA request line |
| "tx": if sai sub-block is configured as playback DAI |
| "rx": if sai sub-block is configured as capture DAI |
| - pinctrl-names: should contain only value "default" |
| - pinctrl-0: see Documentation/devicetree/bindings/pinctrl/pinctrl-stm32.txt |
| |
| Example: |
| sound_card { |
| compatible = "audio-graph-card"; |
| dais = <&sai1b_port>; |
| }; |
| |
| sai1: sai1@40015800 { |
| compatible = "st,stm32f4-sai"; |
| #address-cells = <1>; |
| #size-cells = <1>; |
| ranges; |
| reg = <0x40015800 0x4>; |
| clocks = <&rcc 1 CLK_SAIQ_PDIV>, <&rcc 1 CLK_I2SQ_PDIV>; |
| clock-names = "x8k", "x11k"; |
| interrupts = <87>; |
| |
| sai1b: audio-controller@40015824 { |
| #sound-dai-cells = <0>; |
| compatible = "st,stm32-sai-sub-b"; |
| reg = <0x40015824 0x1C>; |
| clocks = <&rcc 1 CLK_SAI2>; |
| clock-names = "sai_ck"; |
| dmas = <&dma2 5 0 0x400 0x0>; |
| dma-names = "tx"; |
| pinctrl-names = "default"; |
| pinctrl-0 = <&pinctrl_sai1b>; |
| |
| ports { |
| #address-cells = <1>; |
| #size-cells = <0>; |
| |
| sai1b_port: port@0 { |
| reg = <0>; |
| cpu_endpoint: endpoint { |
| remote-endpoint = <&codec_endpoint>; |
| audio-graph-card,format = "i2s"; |
| audio-graph-card,bitclock-master = <&codec_endpoint>; |
| audio-graph-card,frame-master = <&codec_endpoint>; |
| }; |
| }; |
| }; |
| }; |
| }; |
| |
| audio-codec { |
| codec_port: port { |
| codec_endpoint: endpoint { |
| remote-endpoint = <&cpu_endpoint>; |
| }; |
| }; |
| }; |