• ADAU1401
• ADAU1401A
• ADAU1701
• ADAU1702

• CN0162

• EVAL-ADAU1401AEBZ
• EVAL-ADAU1701MINIZ

ADAU1701 is a SigmaDSP with DACs and ADCs,and support both analog and digital inputs/outputs(I2S). This driver is intended to drive ADAU1701 through I2S, so we adapt it into ASoC framework and treat it as an audio codec, also it needs to include firmware loading function to download firmware blob at the initializing time.

Below is an example which is used on Blackfin board file.

static struct i2c_board_info __initdata bfin_i2c_board_info[] = {
?
	[--snip--]
#if defined(CONFIG_SND_SOC_ADAU1701) || defined(CONFIG_SND_SOC_ADAU1701_MODULE)
	{
		I2C_BOARD_INFO("adau1701", 0x34),
	},
#endif
	[--snip--]
}

static int __init stamp_init(void)
{
	[--snip--]
	i2c_register_board_info(0, bfin_i2c_board_info,
				ARRAY_SIZE(bfin_i2c_board_info));
	[--snip--]
?
	return 0;
}
arch_initcall(board_init);

The CODEC driver register one DAI called “adau1701”.

The sysclk source can be either be generated using the internal oscillator and an external crystal, or can come from an external clock signal.

enum adau1701_clk_src {
    ADAU1701_CLK_SRC_OSC,
    ADAU1701_CLK_SRC_MCLK,
};

The sysclk rate is configured using the PLL_MODE0 and PLL_MODE1 pins. Though for completeness it should also be passed to snd_soc_dai_set_sysclk.

static int bfin_eval_adau1701_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 *cpu_dai = rtd->cpu_dai;
	struct snd_soc_dai *codec_dai = rtd->codec_dai;
	int ret;
?
	ret = snd_soc_dai_set_fmt(cpu_dai, SND_SOC_DAIFMT_I2S |
			SND_SOC_DAIFMT_NB_NF | SND_SOC_DAIFMT_CBM_CFM);
	if (ret)
		return ret;
?
	ret = snd_soc_dai_set_fmt(codec_dai, SND_SOC_DAIFMT_I2S |
			SND_SOC_DAIFMT_NB_NF | SND_SOC_DAIFMT_CBM_CFM);
	if (ret)
		return ret;
?
	ret = snd_soc_dai_set_sysclk(codec_dai, ADAU1701_CLK_SRC_OSC, 12288000,
			SND_SOC_CLOCK_IN);
?
	return ret;
}
?
static struct snd_soc_ops bfin_eval_adau1701_ops = {
	.hw_params = bfin_eval_adau1701_hw_params,
};
?
static struct snd_soc_dai_link bfin_eval_adau1701_dai = {
	.name = "adau1701",
	.stream_name = "adau1701",
	.cpu_dai_name = "bfin-i2s.0",
	.codec_dai_name = "adau1701",
	.platform_name = "bfin-i2s-pcm-audio",
	.codec_name = "adau1701.0-0034",
	.ops = &bfin_eval_adau1701_ops,
};

In order to use the SigmaDSP core of the ADAU1701 you need to provide a firmware file. Please refer to the SigmaDSP Firmware Utility for Linux page on how to generate a firmware file. The firmware file for ADAU1701 driver has to be named adau1701.bin.

There is no dedicated Blackfin STAMP evaluation board for the ADAU1701. During test and driver development we used the EVAL-ADAU1701MINIZ board.

It can be easily wired to the Blackfin STAMP SPORT header.

Device Drivers  --->
[*] I2C support  --->
[*]   I2C Hardware Bus support  --->
***     I2C system bus drivers (mostly embedded / system-on-chip) ***
<*>       Blackfin TWI I2C support
(100)     Blackfin TWI I2C clock (kHz)

Enable ALSA SoC evaluation board driver:

Device Drivers  --->
 Sound card support  --->
   Advanced Linux Sound Architecture  --->
     ALSA for SoC audio support  --->
       Support for the EVAL-ADAU1701 boards on Blackfin eval boards

TODO

Load the driver and make sure the sound card is properly instantiated.

root:/> modprobe snd-bf5xx-i2s
root:/> modprobe snd-soc-bf5xx-i2s
root:/> modprobe snd-soc-adau1701
root:/> modprobe snd-soc-bfin-eval-adau1701
dma rx:3 tx:4, err irq:45, regs:ffc00800
asoc: ADAU1701 <-> bf5xx-i2s mapping ok

root:/> modprobe snd-pcm-oss
root:/> tone
TONE: generating sine wave at 1000 Hz...

root:/> arecord -f cd | aplay
Recording WAVE 'stdin' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo
Playing WAVE 'stdin' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo

• SigmaStudio
• SigmaDSP Firmware Utility for Linux