Kernel-4.18.0-80.el8_fsl,esai

Freescale Enhanced Serial Audio Interface (ESAI) Controller

The Enhanced Serial Audio Interface (ESAI) provides a full-duplex serial port
for serial communication with a variety of serial devices, including industry
standard codecs, Sony/Phillips Digital Interface (S/PDIF) transceivers, and
other DSPs. It has up to six transmitters and four receivers.

Required properties:

  • compatible : Compatible list, must contain “fsl,imx35-esai” or

          "fsl,vf610-esai"
    
  • reg : Offset and length of the register set for the device.

  • interrupts : Contains the spdif interrupt.

  • dmas : Generic dma devicetree binding as described in

          Documentation/devicetree/bindings/dma/dma.txt.
    
  • dma-names : Two dmas have to be defined, “tx” and “rx”.

  • clocks : Contains an entry for each entry in clock-names.

  • clock-names : Includes the following entries:
    “core” The core clock used to access registers
    “extal” The esai baud clock for esai controller used to

          derive HCK, SCK and FS.
    

    “fsys” The system clock derived from ahb clock used to

          derive HCK, SCK and FS.
    

    “spba” The spba clock is required when ESAI is placed as a

          bus slave of the Shared Peripheral Bus and when two
          or more bus masters (CPU, DMA or DSP) try to access
          it. This property is optional depending on the SoC
          design.
    
  • fsl,fifo-depth : The number of elements in the transmit and receive

          FIFOs. This number is the maximum allowed value for
          TFCR[TFWM] or RFCR[RFWM].
    
  • fsl,esai-synchronous: This is a boolean property. If present, indicating

          that ESAI would work in the synchronous mode, which
          means all the settings for Receiving would be
          duplicated from Transmition related registers.
    

Optional properties:

  • big-endian : If this property is absent, the native endian mode
          will be in use as default, or the big endian mode
          will be in use for all the device registers.
    

Example:

esai: esai@2024000 {
compatible = “fsl,imx35-esai”;
reg = <0x02024000 0x4000>;
interrupts = <0 51 0x04>;
clocks = <&clks 208>, <&clks 118>, <&clks 208>;
clock-names = “core”, “extal”, “fsys”;
dmas = <&sdma 23 21 0>, <&sdma 24 21 0>;
dma-names = “rx”, “tx”;
fsl,fifo-depth = <128>;
fsl,esai-synchronous;
big-endian;
};