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This version (22 Jul 2013 18:33) was approved by larsc.The Previously approved version (05 Sep 2012 14:23) is available.Diff

ADAU1701 Sound Audio System Linux Driver

Supported Devices

Reference Circuits

Evaluation Boards

Description

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.

Source Code

Status

Source Mainlined?
git Yes

Files

Example platform device initialization

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);

ASoC DAPM widgets

Name Description
OUT0 VOUT0 DAC Output
OUT1 VOUT1 DAC Output
OUT2 VOUT2 DAC Output
OUT3 VOUT3 DAC Output
IN0 Analog Audio Input 0 (ADC0)
IN1 Analog Audio Input 1 (ADC1)

ALSA controls

Name Description
Master Capture Switch Mute/Unmute the ADCs

DAI Configuration

The CODEC driver register one DAI called “adau1701”.

Supported DAI formats

Name Supported by driver Description
SND_SOC_DAIFMT_I2S yes I2S Justified mode
SND_SOC_DAIFMT_RIGHT_J yes Right Justified mode
SND_SOC_DAIFMT_LEFT_J yes Left Justified mode
SND_SOC_DAIFMT_DSP_A no data MSB after FRM LRC
SND_SOC_DAIFMT_DSP_B no data MSB during FRM LRC
SND_SOC_DAIFMT_AC97 no AC97 mode
SND_SOC_DAIFMT_PDM no Pulse density modulation
SND_SOC_DAIFMT_NB_NF yes Normal bit- and frameclock
SND_SOC_DAIFMT_NB_IF yes Normal bitclock, inverted frameclock
SND_SOC_DAIFMT_IB_NF yes Inverted frameclock, normal bitclock
SND_SOC_DAIFMT_IB_IF yes Inverted bit- and frameclock
SND_SOC_DAIFMT_CBM_CFM yes Codec bit- and frameclock master
SND_SOC_DAIFMT_CBS_CFM no Codec bitclock slave, frameclock master
SND_SOC_DAIFMT_CBM_CFS no Codec bitclock master, frameclock slave
SND_SOC_DAIFMT_CBS_CFS yes Codec bit- and frameclock slave

Sysclk Configuration

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.

Example DAI Configuration

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,
};

Generate the firmware file

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.

ADAU1701 evaluation board driver

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.

Source Code

Status

Source Mainlined?
git Yes

Files

Kernel configuration

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

Hardware configuration

TODO

Driver testing

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

This specifies any shell prompt running on the target

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

This specifies any shell prompt running on the target

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

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