ADAU7118

ADAU7118 8 Channel, PDM to I2S or TDM Conversion IC Linux Driver.

Supported Devices

• ADAU7118

Evaluation Boards

• EVAL-ADAU7118

Description

The ADAU7118 converts four stereo pulse density modulation (PDM) bitstreams into one pulse code modulation (PCM) output stream. The source for the PDM data can be eight microphones or other PDM sources. The PCM audio data is output on a serial audio interface port in either inter-IC serial (I2S) or time domain multiplexed (TDM) format. The ADAU7118 has an I2C interface which can be used to fully configure the device. It can set the device to operate either in stereo or TDM mode, disable/enable inputs, etc… Furthermore, the device can also operate in HW only mode where the I2C interface is disabled. In this mode, only TDM mode is supported.

Status

Source	Mainlined?
sound/soc/codecs/adau7118.c	yes
sound/soc/codecs/adau7118.h	yes
sound/soc/codecs/adau7118-i2c.c	yes
sound/soc/codecs/adau7118-hw.c	yes

Files

Function	File
core driver	sound/soc/codecs/adau7118.c
core include	sound/soc/codecs/adau7118.h
driver	sound/soc/codecs/adau7118-i2c.c
driver	sound/soc/codecs/adau7118-hw.c
devicetree	Documentation/devicetree/bindings/sound/adi,adau7118.yaml

Devicetree bindings

The ADAU7118 driver is fully devicetree compatible.

Required properties:

• compatible: Must be adi,adau7118

• #sound-dai-cells: Must be 0

Optional properties:

• reg: I2C address when the device is used with I2C support.

• IOVDD-supply: Phandle and specifier for the power supply providing the IOVDD supply as covered in Documentation/devicetree/bindings/regulator/regulator.txt. If this property is not present it is assumed that the supply pin is hardwired to always on.

• DVDD-supply: Phandle and specifier for the power supply providing the DVDD supply as covered in Documentation/devicetree/bindings/regulator/regulator.txt. If this property is not present it is assumed that the supply pin is hardwired to always on.

• adi,decimation-ratio: Set’s the decimation ratio of PDM to PCM audio data.

• adi,pdm-clk-map: The ADAU7118 has two PDM clocks for the four Inputs. Each input must be assigned to one of these two clocks. This property set’s the mapping between the clocks and the inputs.

Example device initialization

The ADAU7118 supports I2C interface and can operate in HW only mode (no communications with the device). Currently, the devices can only be instantiated via device tree.

I2C mode

i2c0 {
         #address-cells = <1>;
         #size-cells = <0>;
         status = "okay";
         adau7118_codec: adau7118-codec@14 {
                 compatible = "adi,adau7118";
                 reg = <0x14>;
                 status = "okay";
                 adi,pdm-clk-map = <1 1 0 0>;
                 adi,decimation-ratio = <16>;
         };
};

HW mode

/ {
         adau7118_codec: adau7118-codec@14 {
                 compatible = "adi,adau7118";
                 reg = <0x14>;
                 status = "okay";
                 IOVDD-supply = <&supply>;
                 DVDD-supply = <&supply2>;
         };
};

Kernel configuration

Device Drivers  --->
<*> Sound card support  --->
<*>   Advanced Linux Sound Architecture  --->
<*>     ALSA for SoC audio support  --->
<*>       CODEC drivers  --->
<*>          Analog Devices ADAU7118 8 Channel PDM-to-I2S/TDM Converter - HW Mode
<*>          Analog Devices ADAU7118 8 Channel PDM-to-I2S/TDM Converter - I2C

ASoC DAPM widgets (HW Mode)

Name	Description
PDM_DAT0	PDM0 signal input
PDM_DAT1	PDM1 signal input
PDM_DAT2	PDM2 signal input
PDM_DAT3	PDM3 signal input
AIF1TX	Audio Interface Output

ASoC DAPM widgets (I2C)

Name	Description
PDM_DAT0	PDM0 signal input
PDM_DAT1	PDM1 signal input
PDM_DAT2	PDM2 signal input
PDM_DAT3	PDM3 signal input
PDM0	PDM0 switch control
PDM1	PDM1 switch control
PDM2	PDM2 switch control
PDM3	PDM3 switch control
PDM_CLK0	Clock0 supply widget
PDM_CLK1	Clock1 supply widget
AIF1TX1	Audio Interface Output - Channel 1
AIF1TX2	Audio Interface Output - Channel 2
AIF1TX3	Audio Interface Output - Channel 3
AIF1TX4	Audio Interface Output - Channel 4
AIF1TX5	Audio Interface Output - Channel 5
AIF1TX6	Audio Interface Output - Channel 6
AIF1TX7	Audio Interface Output - Channel 7
AIF1TX8	Audio Interface Output - Channel 8

ALSA controls

Name	Description
Capture Switch	PDM0 input enable
Capture Switch	PDM1 input enable
Capture Switch	PDM2 input enable
Capture Switch	PDM3 input enable

DAI Configuration

The driver registers one DAI called ``adau7118-hifi-capture``.

Supported DAI formats

Name	Supported by driver	Description
SND_SOC_DAIFMT_I2S	yes*	I2S 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	no	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

* The supported DAI format are limited for HW only mode (only I2S and Normal bit- and frameclock is supported). In this mode, the I2C SCL and SDA pins are used to select different functionality. Check table 11 of the datasheet for more details.

More information

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