Hello,
I need your help!!!
I am trying to send 30 channel microphones from DSP board to Beaglebone
black. I design with 3 TDM lines, each line 10 slot.
I could check the correct signal sending from DSP by oscilloscope (DSP
generate bit clock, frame clock )
When I do the record with 30 channels, it notices 'Division by zero in
kernel'
debian@beaglebone:~$ arecord -f S24_LE -d3 -r 48000 -c30 test.wav
Recording WAVE 'test.wav' : [65667.290731] Division by zero in kernel.
Signed 24 bit Little Endian, Rate 48000 Hz, Channels 30
dmesg said the bclk from 'snd_soc_params_to_bclk(params)' is 34560000. How
the kernel get this number? It sould be 15360000=48000*32*10
*[65667.290633] bclk (from params): 34560000[65667.290660] fs:
48000[65667.290667] sysclk: 24576000[65667.290672] bclk:
15360000[65667.290684] evm_dsp56725_hw_params: Starting
operations.[65667.290690] sysclk=24576000[65667.290696]
bclk_freq=15360000[65667.290731] Division by zero in kernel.*
This is my modification in dts:
/* dsp56725 cape */
mcasp0_pins_dsp56725: mcasp0_pins_dsp56725 {
pinctrl-single,pins = <
AM33XX_IOPAD(0x9a4, 0x20) /* mcasp0_fsr, MODE0 | INPUT P9_27 GPIO3_19 */
AM33XX_IOPAD(0x878, 0x26) /* mcasp0_aclkr_mux3, MODE6 | INPUT P9_12
gpio1_28 */
AM33XX_IOPAD(0x998, 0x20) /* mcasp0_axr0, MODE0 | INPUT P9_30 GPIO3_16 */
AM33XX_IOPAD(0x99c, 0x22) /* mcasp0_axr2 MODE2 | INPUT P9_28 GPIO3_17 */
AM33XX_IOPAD(0x9ac, 0x22) /* mcasp0_axr3, MODE2 | INPUT P9_25 GPIO3_21*/
/*OFFSET DIR|MODE */
;
};
&mcasp0 {
pinctrl-names = "default";
pinctrl-0 = <&mcasp0_pins_dsp56725>;
status = "okay";
op-mode = <0>; /* MCASP_IIS_MODE */
tdm-slots = <10>;
num-serializer = <4>;
serial-dir = < /* 0: INACTIVE, 1: TX, 2: RX */
2 0 2 2
;
tx-num-evt = <0>;
rx-num-evt = <1>;
};
/ {
dsp56725: dsp56725 {
compatible = "ti,dsp56725";
};
sound {
compatible = "ti,beaglebone-black-dsp56725";
ti,model = "DSP56725";
ti,audio-codec = <&dsp56725>;
ti,mcasp-controller = <&mcasp0>;
ti,codec-clock-rate = <24576000>;
};
};
During testing, I try to record with less than 15 channels it could record
but it seems it only read data on the line mcasp0_axr0. How could I config
to read 3 lines TDM simultaneously.
debian@beaglebone:~$ arecord -f S24_LE -d3 -r 48000 -c14 test.wav
Recording WAVE 'test.wav' : Signed 24 bit Little Endian, Rate 48000 Hz,
Channels 14
debian@beaglebone:~$
*[66387.103351] bclk (from params): 11520000[66387.103378] fs:
48000[66387.103385] sysclk: 24576000[66387.103390] bclk:
15360000[66387.103401] evm_dsp56725_hw_params: Starting
operations.[66387.103407] sysclk=24576000[66387.103413] bclk_freq=15360000*
Thank You!
