Simple-Card:
Simple-Card specifies audio DAI connections of SoC <-> codec.
Required properties:
- compatible : “simple-audio-card”
Optional properties:
- simple-audio-card,name : User specified audio sound card name, one string
property. - simple-audio-card,widgets : Please refer to widgets.txt.
- simple-audio-card,routing : A list of the connections between audio components.
Each entry is a pair of strings, the first being the connection's sink, the second being the connection's source. - simple-audio-card,mclk-fs : Multiplication factor between stream rate and codec
mclk. When defined, mclk-fs property defined in dai-link sub nodes are ignored. - simple-audio-card,hp-det-gpio : Reference to GPIO that signals when
headphones are attached. - simple-audio-card,mic-det-gpio : Reference to GPIO that signals when
a microphone is attached. - simple-audio-card,aux-devs : List of phandles pointing to auxiliary devices, such
as amplifiers, to be added to the sound card.
Optional subnodes:
- simple-audio-card,dai-link : Container for dai-link level
properties and the CPU and CODEC sub-nodes. This container may be omitted when the card has only one DAI link. See the examples and the section below.
Dai-link subnode properties and subnodes:
If dai-link subnode is omitted and the subnode properties are directly
under “sound”-node the subnode property and subnode names have to be
prefixed with “simple-audio-card,”-prefix.
Required dai-link subnodes:
- cpu : CPU sub-node
- codec : CODEC sub-node
Optional dai-link subnode properties:
- format : CPU/CODEC common audio format.
"i2s", "right_j", "left_j" , "dsp_a" "dsp_b", "ac97", "pdm", "msb", "lsb" - frame-master : Indicates dai-link frame master.
phandle to a cpu or codec subnode. - bitclock-master : Indicates dai-link bit clock master.
phandle to a cpu or codec subnode. - bitclock-inversion : bool property. Add this if the
dai-link uses bit clock inversion. - frame-inversion : bool property. Add this if the
dai-link uses frame clock inversion. - mclk-fs : Multiplication factor between stream
rate and codec mclk, applied only for the dai-link.
For backward compatibility the frame-master and bitclock-master
properties can be used as booleans in codec subnode to indicate if the
codec is the dai-link frame or bit clock master. In this case there
should be no dai-link node, the same properties should not be present
at sound-node level, and the bitclock-inversion and frame-inversion
properties should also be placed in the codec node if needed.
Required CPU/CODEC subnodes properties:
- sound-dai : phandle and port of CPU/CODEC
Optional CPU/CODEC subnodes properties:
- dai-tdm-slot-num : Please refer to tdm-slot.txt.
- dai-tdm-slot-width : Please refer to tdm-slot.txt.
- clocks / system-clock-frequency : specify subnode’s clock if needed.
it can be specified via "clocks" if system has clock node (= common clock), or "system-clock-frequency" (if system doens't support common clock) If a clock is specified, it is enabled with clk_prepare_enable() in dai startup() and disabled with clk_disable_unprepare() in dai shutdown(). If a clock is specified and a multiplication factor is given with mclk-fs, the clock will be set to the calculated mclk frequency when the stream starts. - system-clock-direction-out : specifies clock direction as ‘out’ on
initialization. It is useful for some aCPUs with fixed clocks.
Example 1 - single DAI link:
sound {
compatible = “simple-audio-card”;
simple-audio-card,name = “VF610-Tower-Sound-Card”;
simple-audio-card,format = “left_j”;
simple-audio-card,bitclock-master = <&dailink0_master>;
simple-audio-card,frame-master = <&dailink0_master>;
simple-audio-card,widgets =
“Microphone”, “Microphone Jack”,
“Headphone”, “Headphone Jack”,
“Speaker”, “External Speaker”;
simple-audio-card,routing =
“MIC_IN”, “Microphone Jack”,
“Headphone Jack”, “HP_OUT”,
“External Speaker”, “LINE_OUT”;
simple-audio-card,cpu {
sound-dai = <&sh_fsi2 0>;
};
dailink0_master: simple-audio-card,codec {
sound-dai = <&ak4648>;
clocks = <&osc>;
};
};
&i2c0 {
ak4648: ak4648@12 {
#sound-dai-cells = <0>;
compatible = “asahi-kasei,ak4648”;
reg = <0x12>;
};
};
sh_fsi2: sh_fsi2@ec230000 {
#sound-dai-cells = <1>;
compatible = “renesas,sh_fsi2”;
reg = <0xec230000 0x400>;
interrupt-parent = <&gic>;
interrupts = <0 146 0x4>;
};
Example 2 - many DAI links:
sound {
compatible = “simple-audio-card”;
simple-audio-card,name = “Cubox Audio”;
simple-audio-card,dai-link@0 { /* I2S - HDMI */
reg = <0>;
format = "i2s";
cpu {
sound-dai = <&audio1 0>;
};
codec {
sound-dai = <&tda998x 0>;
};
};
simple-audio-card,dai-link@1 { /* S/PDIF - HDMI */
reg = <1>;
cpu {
sound-dai = <&audio1 1>;
};
codec {
sound-dai = <&tda998x 1>;
};
};
simple-audio-card,dai-link@2 { /* S/PDIF - S/PDIF */
reg = <2>;
cpu {
sound-dai = <&audio1 1>;
};
codec {
sound-dai = <&spdif_codec>;
};
};
};
Example 3 - route audio from IMX6 SSI2 through TLV320DAC3100 codec
through TPA6130A2 amplifier to headphones:
&i2c0 {
codec: tlv320dac3100@18 {
compatible = “ti,tlv320dac3100”;
…
}
amp: tpa6130a2@60 {
compatible = "ti,tpa6130a2";
...
}
}
sound {
compatible = “simple-audio-card”;
…
simple-audio-card,widgets =
“Headphone”, “Headphone Jack”;
simple-audio-card,routing =
“Headphone Jack”, “HPLEFT”,
“Headphone Jack”, “HPRIGHT”,
“LEFTIN”, “HPL”,
“RIGHTIN”, “HPR”;
simple-audio-card,aux-devs = <&>;
simple-audio-card,cpu {
sound-dai = <&ssi2>;
};
simple-audio-card,codec {
sound-dai = <&codec>;
clocks = …
};
};
