linux_dsm_epyc7002/Documentation/devicetree/bindings/sound/st,stm32-sai.txt
Olivier Moysan 14f0e5f8d9 ASoC: stm32: Add synchronization to SAI bindings
Add synchronization configuration to STM32 SAI bindings.
This patch also adds peripheral clock which is required
to access synchronization register.

Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2017-10-21 11:17:27 +01:00

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>;
};
};
};