This directory contains all the supported audio devices
Device name | Description |
---|---|
a2dp | Bluetooth A2DP connection. When selected, the default input (onboard mic) is selected. |
btsco | Bluetooth SCO/HFP connection. |
hac | HAC telecoil used for hearing aids. When selected, the default input (onboard mic) is selected. |
handset | The handset on the device phone receiver. When selected, the default input (onboard mic) is selected. |
hdmi | HDMI audio connection. When selected, the default input (onboard mic) is selected. |
headphone | Headphone with no mic input. When selected, the default input (onboard mic) is selected. |
headset | Headset with mic input. |
lineout | An output device connected through the headset jack. When selected, the default input (onboard mic) is selected. |
speaker | The main speaker on the device (handsfree on mobile phones). |
tones | A virtual audio device for the system tones. |
tty | Telecommunications device for the deaf (connected through the headphone jack). |
usb | Used for USB audio devices. |
voice | A virtual audio device for voice content. |
The status of the default audio device is published to the /pps/services/audio/devices/default object.
The default device has the following attributes:
Attribute | Description |
---|---|
device | Name of the default audio device used for playback (e.g., speaker). |
path | Path to the actual audio interface for input and output (e.g., /dev/snd/pcmPreferredp). |
Each device has the following attributes:
Attribute | Data type | Description |
---|---|---|
audioconfig | String | Configuration of the audio output channels (e.g., "2.0", "5.1"). Note that this is used only by the hdmi device. |
connected | Boolean | Indicates whether a given device is connected. |
controlpps | String | The path of the device's PPS control object. If this object exists, then the device is controlled by a PPS interface instead of an actual audio driver. |
dependency | Boolean | Indicates whether this device depends on another device (this device has no effect unless the other is also connected). |
input | Boolean | Indicates whether the device has input. |
keepalive | Boolean | Indicates whether the output device is to be kept alive when no audio stream is active. |
numchans | Number | Number of audio channels supported by the device. |
order | String | The channel order (e.g., FL,FR) for two channels. Note that this is used only by the hdmi device. |
path | String | Path to the actual audio interface for input and output (e.g., /dev/snd/pcmPreferredp). |
supported | Boolean | Indicates whether the device is physically installed on the target. |
suspended | Boolean | Indicates whether the device is temporarily disabled by the system. |
volumecontrol | String | Type of volume control supported:
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