Kernel-4.18.0-80.el8_spi-stm32

STMicroelectronics STM32 SPI Controller

The STM32 SPI controller is used to communicate with external devices using
the Serial Peripheral Interface. It supports full-duplex, half-duplex and
simplex synchronous serial communication with external devices. It supports
from 4 to 32-bit data size. Although it can be configured as master or slave,
only master is supported by the driver.

Required properties:

  • compatible: Must be “st,stm32h7-spi”.
  • reg: Offset and length of the device’s register set.
  • interrupts: Must contain the interrupt id.
  • clocks: Must contain an entry for spiclk (which feeds the internal clock
    generator).
    
  • #address-cells: Number of cells required to define a chip select address.
  • #size-cells: Should be zero.

Optional properties:

  • resets: Must contain the phandle to the reset controller.
  • A pinctrl state named “default” may be defined to set pins in mode of
    operation for SPI transfer.
  • dmas: DMA specifiers for tx and rx dma. DMA fifo mode must be used. See the
    STM32 DMA bindings, Documentation/devicetree/bindings/dma/stm32-dma.txt.
  • dma-names: DMA request names should include “tx” and “rx” if present.
  • cs-gpios: list of GPIO chip selects. See the SPI bus bindings,
    Documentation/devicetree/bindings/spi/spi-bus.txt

Child nodes represent devices on the SPI bus
See ../spi/spi-bus.txt

Optional properties:

  • st,spi-midi-ns: (Master Inter-Data Idleness) minimum time delay in
        nanoseconds inserted between two consecutive data frames.
    

Example:
spi2: spi@40003800 {
#address-cells = <1>;
#size-cells = <0>;
compatible = “st,stm32h7-spi”;
reg = <0x40003800 0x400>;
interrupts = <36>;
clocks = <&rcc SPI2_CK>;
resets = <&rcc 1166>;
dmas = <&dmamux1 0 39 0x400 0x01>,
<&dmamux1 1 40 0x400 0x01>;
dma-names = “rx”, “tx”;
pinctrl-0 = <&spi2_pins_b>;
pinctrl-names = “default”;
cs-gpios = <&gpioa 11 0>;

    aardvark@0 {
        compatible = "totalphase,aardvark";
        reg = <0>;
        spi-max-frequency = <4000000>;
        st,spi-midi-ns = <4000>;
    };
};