AM335X: WM8960 codec

Ahn

Intellectual 1000 points

hi,

I want play the audio file with wm8960 codec chip.

But, MCLK & BCLK are not set to the desired value.

current value desired value

MCLk = 24.576Mhz 12.288Mhz

BCLK = 2.738Mhz 3.072Mhz

if reducing the MCLK using the below function:

snd_soc_dai_set_clkdiv(cpu_dai, 0, 2);

current value desired value

MCLk = 12.288Mhz 12.288Mhz

BCLK = 1.369Mhz 3.072Mhz

How can I get the desired value?

Here is my environment:

linux-3.14.26-g2489c02

MCASP0

wm8960

Here is my device tree:

&am33xx_pinmux {

mcasp0_pins: mcasp0_pins {
  pinctrl-single,pins = <
   0x1ac (PIN_INPUT_PULLUP | MUX_MODE0) /* mcasp0_ahclkx.mcasp0_ahclkx */
   0x190 (PIN_OUTPUT_PULLDOWN | MUX_MODE0) /* mcasp0_aclkx.mcasp0_aclkx */
   0x194 (PIN_OUTPUT_PULLUP | MUX_MODE0) /* mcasp0_fsx.mcasp0_fsx */
   0x198 (PIN_OUTPUT_PULLDOWN | MUX_MODE0) /* mcasp0_axr0.mcasp0_axr0 */
  >;
};

mcasp0_pins_sleep: mcasp0_pins_sleep {
  pinctrl-single,pins = <
   0x1ac (PIN_INPUT_PULLDOWN | MUX_MODE7) /* mcasp0_ahclkx.mcasp0_ahclkx */
   0x190 (PIN_INPUT_PULLDOWN | MUX_MODE7) /* mcasp0_aclkx.mcasp0_aclkx */
   0x194 (PIN_INPUT_PULLDOWN | MUX_MODE7) /* mcasp0_fsx.mcasp0_fsx */
   0x198 (PIN_INPUT_PULLDOWN | MUX_MODE7) /* mcasp0_axr0.mcasp0_axr0 */
  >;
};

};

&mcasp0 {
pinctrl-names = "default", "sleep";
pinctrl-0 = <&mcasp0_pins>;
pinctrl-1 = <&mcasp0_pins_sleep>;
status = "okay";
op-mode = <0>; /* MCASP_IIS_MODE */
tdm-slots = <2>;
serial-dir = < /* 0: INACTIVE, 1: TX, 2: RX */
1 0 0 0
>;
tx-num-evt = <1>;
rx-num-evt = <1>;
};

&i2c0 {
wm8960:wm8960@1a {
  compatible = "wlf,wm8960";
  reg = <0x1a>;
  status = "okay";
  wlf,shared-lrclk;
};
};

/ {
sound {
  compatible = "ti,wm8960-evm-audio";
  ti,model = "WM8960";
  ti,audio-codec = <&wm8960>;
  ti,mcasp-controller = <&mcasp0>;
  ti,codec-clock-rate = <12288000>;
};
};

Here is my davinci-evm.c added code:

static int evm_wm8960_hw_params(struct snd_pcm_substream *substream,
              struct snd_pcm_hw_params *params)
{
     struct snd_soc_pcm_runtime *rtd = substream->private_data;
     struct snd_soc_dai *codec_dai = rtd->codec_dai;
     struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
     struct snd_soc_card *soc_card = rtd->card;
     int ret = 0;
     unsigned sysclk = ((struct snd_soc_card_drvdata_davinci *)
                snd_soc_card_get_drvdata(soc_card))->sysclk;

     /* set the codec system clock */
     ret = snd_soc_dai_set_sysclk(codec_dai, 0, sysclk, SND_SOC_CLOCK_IN);
     if (ret < 0)
     {
         printk("[%s] codec_dai snd_soc_dai_set_sysclk err(0x%x)\n", __func__, ret);
         return ret;
     }

     /* set the CPU system clock */
     ret = snd_soc_dai_set_sysclk(cpu_dai, 0, sysclk, SND_SOC_CLOCK_OUT);
     if (ret < 0)
     {
         printk("[%s] cpu_dai snd_soc_dai_set_sysclk err\n", __func__);
         return ret;
     }

     return 0;
}

static int evm_wm8960_init(struct snd_soc_pcm_runtime *rtd)
{

return 0;
}

static struct snd_soc_dai_link evm_dai_wm8960 = {
     .name       = "wm8960",
     .stream_name    = "Playback",
     .codec_dai_name = "wm8960-hifi",
     .ops            = &evm_wm8960_ops,
     .init           = evm_wm8960_init,
     .dai_fmt = SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_CBS_CFS |
         SND_SOC_DAIFMT_IB_NF,
};

static const struct of_device_id davinci_evm_dt_ids[] = {

  {
   .compatible = "ti,wm8960-evm-audio",
   .data = &evm_dai_wm8960,
  },
};

over 10 years ago

0 Biser Gatchev-XID over 10 years ago

TI__Guru**** 393215 points

Hi,

Where do the MCLK and BCLK come from - external codec?

0 Ahn over 10 years ago in reply to Biser Gatchev-XID

Intellectual 1000 points

Hi,
codec is slave mode.
MCLK and BCLK come from cpu.

0 Biser Gatchev-XID over 10 years ago in reply to Ahn

TI__Guru**** 393215 points

I suppose you have an external MCLK source. There is no way that AM335X can provide 24.576Mhz from internal source.

0 Ahn over 10 years ago in reply to Biser Gatchev-XID

Intellectual 1000 points

Hi,

I need a following clock.

MCLK = 12.288Mhz
BCLK = 3.072Mhz

0 Biser Gatchev-XID over 10 years ago in reply to Ahn

TI__Guru**** 393215 points

If you use AM335X internal clock source there is no way to achieve the frequencies you require. McASP internal clock source is AUXCLK, which is the AM335X main oscillator clock. AM335X can work only with 19.2MHz, 24MHz, 25MHz or 26MHz main oscillator frequencies. There is no internal PLL in AM335X to generate 12.288MHz from one of these frequencies.

0 Ahn over 10 years ago in reply to Biser Gatchev-XID

Intellectual 1000 points

Hi,
I will change the codec configuration.
codec is master mode.
MCLK come from cpu : 24MHz
BCLK come from codec( using by codec pll) : 3.072Mhz

How to setup the following item?
snd_soc_dai_set_sysclk
dai_fmt

0 Yordan Kovachev over 10 years ago in reply to Ahn

TI__Guru**** 161600 points

Hi,

If you are using the internal 24MHz clock, then you should set the following in davinci-mcasp.c:
ret = snd_soc_dai_set_sysclk(cpu_dai, 0, sysclk, SND_SOC_CLOCK_OUT);
Detailed description of what you should do can be found here: processors.wiki.ti.com/.../Sitara_Linux_Audio_DAC_Example

About dai_fmt, have a look at: processors.wiki.ti.com/.../Sitara_Linux_Audio_DAC_Example
Options that can be assigned to dai_fmt are described in the davinci-mcasp.c driver.

Hope this helps.

Best Regards,
Yordan

0 Filippo Signori over 8 years ago in reply to Yordan Kovachev

Prodigy 10 points

Hello Ahn,

my name is Filippo and I'm working too with a Beaglebone Black and a audio codec WM8960.
Did you manage to get it work.?

If yes is possible to know how.?
I'm struggling with the wm8960 too.

I set the dts file and I have configured the driver to work with the Mcasp but , when I run the command "aplay -l" , I always get " no soundcard found"

Any help will be really really appreciated.

Best regards

Filippo

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AM335X: WM8960 codec