在VIM3最新android版本,预研调试内置loopback功能，数据pipeline为采集数据为TMD_C (D0 D1)，4ch；loopback数据为TDM_B(D1)。tinycap 采集会卡死且采集不到数据
aml-audio-card,dai-link@2 {
mclk-fs = <256>;
//continuous-clock;
bitclock-master = <&loopback>;
frame-master = <&loopback>;
suffix-name = "alsaPORT-loopback";
cpu {
sound-dai = <&loopback>;
system-clock-frequency = <12288000>;
};
codec {
sound-dai = <&loopback_codec>;
};
};
loopback:loopback@0 {
compatible = "amlogic, g12a-loopback";
#sound-dai-cells = <0>;
clocks = <
&clkc CLKID_MPLL1
&clkaudio CLKID_AUDIO_MCLK_B
&clkc CLKID_MPLL2
&clkaudio CLKID_AUDIO_MCLK_C>;
clock-names =
"tdmin_mpll",
"tdmin_mclk",
"tdminlb_mpll",
"tdminlb_mclk";
/* datain src
* 0: tdmin_a;
* 1: tdmin_b;
* 2: tdmin_c;
* 3: spdifin;
* 4: pdmin;
*/
datain_src = <1>;
datain_chnum = <4>;
datain_chmask = <0x0f>;
/* config which data pin for loopback */
datain-lane-mask-in = <1 1 0 0>;
/* calc mclk for datalb */
mclk-fs = <256>;
/* tdmin_lb src
* 0: tdmoutA
* 1: tdmoutB
* 2: tdmoutC
* 3: PAD_TDMINA_DIN*, refer to core pinmux
* 4: PAD_TDMINB_DIN*, refer to core pinmux
* 5: PAD_TDMINC_DIN*, refer to core pinmux
* 6: PAD_TDMINA_D*, oe, refer to core pinmux
* 7: PAD_TDMINB_D*, oe, refer to core pinmux
*/
/* if tdmin_lb >= 3, use external loopback */
datalb_src = <2>;
datalb_chnum = <2>;
datalb_chmask = <0x3>;
/* config which data pin as loopback */
datalb-lane-mask-in = <0 1 0 0>;
status = "okay";
};