PCM3168A SAI Audio In/Out not working at same time

jsmith8831 — Wed, 12 Feb 2025 02:23:19 GMT

Hello,

I have a i.MX8QM with a PCM3168A audio codec, Linux 6.1. I'm trying to use both audio playback and capture at the same time, but it seems that I can only use one at a time. If I make the device tree so that the playback dai-link master is the cpu, I can play audio. But I can't capture audio with this configuration. If I then change the device tree so that the capture dai-link master is the codec, I can record audio but I can't playback audio.

I added "fsl,sai-asynchronous" to the sai0 node, but that didn't seem to allow both to work at the same time. If I probe the ADC lines, I never see a BCLK or LRCLK signals when the cpu is the master, but I do see signals when the codec is the master.

What am I doing wrong? Here's my device tree below:

Playback working, Capture not working:

sound_card: sound-card { compatible = "simple-audio-card"; simple-audio-card,name = "PCM3168A"; simple-audio-card,aux-devs = <&amp>; simple-audio-card,widgets = "Speaker", "Channel1out", "Speaker", "Channel2out", "Speaker", "Channel3out", "Speaker", "Channel4out", "Speaker", "Channel5out", "Speaker", "Channel6out", "Speaker", "Channel7out", "Speaker", "Channel8out", "Microphone", "Channel1in", "Microphone", "Channel2in", "Line", "Channel3in", "Line", "Channel4in", "Microphone", "Channel5in", "Microphone", "Channel6in"; simple-audio-card,routing = "Channel1out", "AOUT1L", "Channel2out", "AOUT1R", "Channel3out", "AOUT2L", "Channel4out", "AOUT2R", "Channel5out", "AOUT3L", "Channel6out", "AOUT3R", "Channel7out", "AOUT4L", "Channel8out", "AOUT4R", "Channel1in", "AIN1L", "Channel2in", "AIN1R", "Channel3in", "AIN2L", "Channel4in", "AIN2R", "Channel5in", "AIN3L", "Channel6in", "AIN3R"; simple-audio-card,dai-link@0 { format = "left_j"; bitclock-master = <&snd_cpu>; frame-master = <&snd_cpu>; mclk-fs = <512>; snd_cpu: cpu { sound-dai = <&sai0>; clocks = <&mclkout0_lpcg 0>; dai-tdm-slot-num = <8>; dai-tdm-slot-width = <32>; }; pcm3168_dac: codec { sound-dai = <&pcm3168a 0>; dai-tdm-slot-num = <8>; dai-tdm-slot-width = <32>; }; }; simple-audio-card,dai-link@1 { format = "left_j"; bitclock-master = <&mic_cpu>; frame-master = <&mic_cpu>; mclk-fs = <512>; mic_cpu: cpu { sound-dai = <&sai0>; clocks = <&mclkout0_lpcg 0>; dai-tdm-slot-num = <8>; dai-tdm-slot-width = <32>; }; pcm3168_adc: codec { sound-dai = <&pcm3168a 1>; dai-tdm-slot-num = <8>; dai-tdm-slot-width = <32>; }; }; };

Capture Working, Playback not working:

simple-audio-card,dai-link@0 { format = "left_j"; bitclock-master = <&snd_cpu>; frame-master = <&snd_cpu>; mclk-fs = <512>; snd_cpu: cpu { sound-dai = <&sai0>; clocks = <&mclkout0_lpcg 0>; dai-tdm-slot-num = <8>; dai-tdm-slot-width = <32>; }; pcm3168_dac: codec { sound-dai = <&pcm3168a 0>; dai-tdm-slot-num = <8>; dai-tdm-slot-width = <32>; }; }; simple-audio-card,dai-link@1 { format = "left_j"; bitclock-master = <&pcm3168_adc>; frame-master = <&pcm3168_adc>; mclk-fs = <512>; mic_cpu: cpu { sound-dai = <&sai0>; clocks = <&mclkout0_lpcg 0>; dai-tdm-slot-num = <8>; dai-tdm-slot-width = <32>; }; pcm3168_adc: codec { sound-dai = <&pcm3168a 1>; dai-tdm-slot-num = <8>; dai-tdm-slot-width = <32>; }; };

SAI0 Node:

&sai0 { #sound-dai-cells = <0>; assigned-clocks = <&clk IMX_SC_R_AUDIO_PLL_0 IMX_SC_PM_CLK_PLL>, <&clk IMX_SC_R_AUDIO_PLL_0 IMX_SC_PM_CLK_SLV_BUS>, <&clk IMX_SC_R_AUDIO_PLL_0 IMX_SC_PM_CLK_MST_BUS>, <&sai0_lpcg 0>; assigned-clock-rates = <786432000>, <49152000>, <12288000>, <49152000>; pinctrl-names = "default"; pinctrl-0 = <&pinctrl_sai0>; fsl,sai-asynchronous; status = "okay"; }; pinctrl_sai0: sai0grp { fsl,pins = < IMX8QM_SPI0_CS1_AUD_SAI0_TXC 0x0600004c // BCKDA IMX8QM_SPI2_CS1_AUD_SAI0_TXFS 0x0600004c // LRCKDA IMX8QM_SPI0_SDI_AUD_SAI0_RXD 0x0600004c // DOUT1 IMX8QM_SPI0_SDO_AUD_SAI0_TXD 0x0600006c // DIN1 IMX8QM_SPI0_SCK_AUD_SAI0_RXC 0x0600004c // BCKAD IMX8QM_SPI0_CS0_AUD_SAI0_RXFS 0x0600004c // LRCKAD >; };

I2C Node:

// Audio Codec (8-channel output, 6-channel input) pcm3168a: audio-codec@44 { compatible = "ti,pcm3168a"; reg = <0x44>; reset-gpios = <&lsio_gpio4 24 GPIO_ACTIVE_LOW>; clocks = <&mclkout0_lpcg 0>; clock-names = "scki"; clock-frequency = <24576000>; assigned-clocks = <&clk IMX_SC_R_AUDIO_PLL_0 IMX_SC_PM_CLK_PLL>, <&clk IMX_SC_R_AUDIO_PLL_0 IMX_SC_PM_CLK_SLV_BUS>, <&clk IMX_SC_R_AUDIO_PLL_0 IMX_SC_PM_CLK_MST_BUS>, <&mclkout0_lpcg 0>; assigned-clock-rates = <786432000>, <49152000>, <24576000>, <49152000>; #sound-dai-cells = <1>; VDD1-supply = <&reg_3v3>; VDD2-supply = <&reg_3v3>; VCCAD1-supply = <&reg_5v0>; VCCAD2-supply = <&reg_5v0>; VCCDA1-supply = <&reg_5v0>; VCCDA2-supply = <&reg_5v0>; pinctrl-names = "default"; pinctrl-0 = <&pinctrl_codec_clk &pinctrl_audio_reset>; };

Re: PCM3168A SAI Audio In/Out not working at same time

jsmith8831 — Wed, 12 Feb 2025 03:17:28 GMT

I figured it out. I noticed the SAI6 and SAI7 nodes had this flag set: fsl,txm-rxs;, which I think means TX=master, RX=slave. After setting this in the SAI0 node, and then making the following changes below, I can now capture and playback audio at the same time.

sound_card: sound-card { compatible = "simple-audio-card"; simple-audio-card,name = "PCM3168A"; simple-audio-card,aux-devs = <&amp>; simple-audio-card,widgets = "Speaker", "Channel1out", "Speaker", "Channel2out", "Speaker", "Channel3out", "Speaker", "Channel4out", "Speaker", "Channel5out", "Speaker", "Channel6out", "Speaker", "Channel7out", "Speaker", "Channel8out", "Microphone", "Channel1in", "Microphone", "Channel2in", "Line", "Channel3in", "Line", "Channel4in", "Microphone", "Channel5in", "Microphone", "Channel6in"; simple-audio-card,routing = "Channel1out", "AOUT1L", "Channel2out", "AOUT1R", "Channel3out", "AOUT2L", "Channel4out", "AOUT2R", "Channel5out", "AOUT3L", "Channel6out", "AOUT3R", "Channel7out", "AOUT4L", "Channel8out", "AOUT4R", "Channel1in", "AIN1L", "Channel2in", "AIN1R", "Channel3in", "AIN2L", "Channel4in", "AIN2R", "Channel5in", "AIN3L", "Channel6in", "AIN3R"; simple-audio-card,dai-link@0 { format = "left_j"; bitclock-master = <&snd_cpu>; frame-master = <&snd_cpu>; mclk-fs = <512>; snd_cpu: cpu { sound-dai = <&sai0>; clocks = <&mclkout0_lpcg 0>; dai-tdm-slot-num = <8>; dai-tdm-slot-width = <32>; }; pcm3168_dac: codec { sound-dai = <&pcm3168a 0>; dai-tdm-slot-num = <8>; dai-tdm-slot-width = <32>; }; }; simple-audio-card,dai-link@1 { format = "left_j"; bitclock-master = <&pcm3168_adc>; frame-master = <&pcm3168_adc>; mclk-fs = <512>; mic_cpu: cpu { sound-dai = <&sai0>; dai-tdm-slot-num = <8>; dai-tdm-slot-width = <32>; }; pcm3168_adc: codec { sound-dai = <&pcm3168a 1>; clocks = <&mclkout0_lpcg 0>; dai-tdm-slot-num = <8>; dai-tdm-slot-width = <32>; }; }; };

i.MX ProcessorsのトピックPCM3168A SAI Audio In/Out not working at same time

PCM3168A SAI Audio In/Out not working at same time

Re: PCM3168A SAI Audio In/Out not working at same time