93 lines
3.1 KiB
Plaintext
93 lines
3.1 KiB
Plaintext
|
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" or "st,stm32h7-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 "pclk" "x8k" and "x11k"
|
||
|
|
"pclk": Clock which feeds the peripheral bus interface.
|
||
|
|
Mandatory for "st,stm32h7-sai" compatible.
|
||
|
|
Not used for "st,stm32f4-sai" compatible.
|
||
|
|
"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
|
||
|
|
- st,sync: specify synchronization mode.
|
||
|
|
By default SAI sub-block is in asynchronous mode.
|
||
|
|
This property sets SAI sub-block as slave of another SAI sub-block.
|
||
|
|
Must contain the phandle and index of the sai sub-block providing
|
||
|
|
the synchronization.
|
||
|
|
|
||
|
|
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
|
||
|
|
|
||
|
|
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 = <&sai1b_port>;
|
||
|
|
};
|
||
|
|
|
||
|
|
sai1: sai1@40015800 {
|
||
|
|
compatible = "st,stm32h7-sai";
|
||
|
|
#address-cells = <1>;
|
||
|
|
#size-cells = <1>;
|
||
|
|
ranges = <0 0x40015800 0x400>;
|
||
|
|
reg = <0x40015800 0x4>;
|
||
|
|
clocks = <&rcc SAI1_CK>, <&rcc PLL1_Q>, <&rcc PLL2_P>;
|
||
|
|
clock-names = "pclk", "x8k", "x11k";
|
||
|
|
interrupts = <87>;
|
||
|
|
|
||
|
|
sai1a: audio-controller@40015804 {
|
||
|
|
compatible = "st,stm32-sai-sub-a";
|
||
|
|
reg = <0x4 0x1C>;
|
||
|
|
clocks = <&rcc SAI1_CK>;
|
||
|
|
clock-names = "sai_ck";
|
||
|
|
dmas = <&dmamux1 1 87 0x400 0x0>;
|
||
|
|
dma-names = "tx";
|
||
|
|
pinctrl-names = "default";
|
||
|
|
pinctrl-0 = <&pinctrl_sai1a>;
|
||
|
|
|
||
|
|
sai1b_port: port {
|
||
|
|
cpu_endpoint: endpoint {
|
||
|
|
remote-endpoint = <&codec_endpoint>;
|
||
|
|
format = "i2s";
|
||
|
|
};
|
||
|
|
};
|
||
|
|
};
|
||
|
|
};
|
||
|
|
|
||
|
|
audio-codec {
|
||
|
|
codec_port: port {
|
||
|
|
codec_endpoint: endpoint {
|
||
|
|
remote-endpoint = <&cpu_endpoint>;
|
||
|
|
};
|
||
|
|
};
|
||
|
|
};
|