This patch adds a document describing common OF bindings for audio devices.
Signed-off-by: Jean-Francois Moine <[email protected]> --- .../devicetree/bindings/sound/audio-interfaces.txt | 101 +++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 Documentation/devicetree/bindings/sound/audio-interfaces.txt diff --git a/Documentation/devicetree/bindings/sound/audio-interfaces.txt b/Documentation/devicetree/bindings/sound/audio-interfaces.txt new file mode 100644 index 0000000..4eddb3f --- /dev/null +++ b/Documentation/devicetree/bindings/sound/audio-interfaces.txt @@ -0,0 +1,101 @@ +Common bindings for audio device graphs + +The graph of the audio ports follows the common binding for device graphs +defined in Documentation/devicetree/bindings/graph.txt. + +Here are described only the audio specific properties. + +Port required properties: + +- port-type: "i2s" or "spdif" + +Port optional property: + +- reg: numeric value which defines how the port is wired to the device. + This value depends on the device. Usually, it is the content + of the device register which controls the audio pins. + +Port required nodes: + +- at least one 'endpoint' node must be specified. + + +Example: + +The board contains an audio controller with two outputs: +- the S/PDIF output is connected to two devices: + - a S/PDIF optical output + - a HDMI transmitter. +- the I2S output is connected to an other audio input of the HDMI transmitter. + + /* audio controller */ + &audio1 { + status = "okay"; + ... + #address-cells = <1>; + #size-cells = <0>; + + /* S/PDIF output */ + port@0 { + port-type = "spdif"; + audio1_spdif0: endpoint@0 { + remote-endpoint = <&spdif_out>; + }; + audio1_spdif1: endpoint@1 { + remote-endpoint = <&tda998x_spdif>; + }; + }; + + /* I2S output */ + port@1 { + port-type = "i2s"; + audio1_i2s: endpoint { + remote-endpoint = <&tda998x_i2s>; + }; + }; + }; + + /* optical output */ + spdif_codec: spdif-codec { + ... + port { + port-type = "spdif"; + spdif_out: endpoint { + remote-endpoint = <&audio1_spdif0>; + }; + }; + }; + + /* HDMI transmitter */ + hdmi: hdmi-encoder { + ... + #address-cells = <1>; + #size-cells = <0>; + + /* video input */ + port@230145 { + port-type = "rgb"; + reg = <0x230145>; + hdmi_0: endpoint { + remote-endpoint = <&lcd0_0>; + }; + }; + + /* audio input I2S on AP1 */ + port@3 { + port-type = "i2s"; + reg = <0x03>; + tda998x_i2s: endpoint { + remote-endpoint = <&audio1_i2s>; + }; + }; + + /* audio input S/PDIF on AP2 */ + port@4 { + port-type = "spdif"; + reg = <0x04>; + tda998x_spdif: endpoint { + remote-endpoint = <&audio1_spdif1>; + }; + }; + }; -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
