System configuration files for the T2 audio driver (https://github.com/MCMrARM/mbp2018-bridge-drv/)

91-pulseaudio-custom.rules

SUBSYSTEM!="sound", GOTO="pulseaudio_end"
ACTION!="change", GOTO="pulseaudio_end"
KERNEL!="card*", GOTO="pulseaudio_end"

SUBSYSTEMS=="pci", ATTRS{vendor}=="0x106b", ATTRS{device}=="0x1803", ENV{PULSE_PROFILE_SET}="apple-t2.conf"

LABEL="pulseaudio_end"

README.md

The files go to:

• /usr/share/alsa/cards/AppleT2.conf
• /usr/share/pulseaudio/alsa-mixer/profile-sets/apple-t2.conf
• /usr/lib/udev/rules.d/91-pulseaudio-custom.rules

apple-t2.conf

[General]
auto-profiles = no

[Mapping builtin-speaker]
description = Built-in Speaker
device-strings = front:%f
paths-output = builtin-speaker-output
channel-map = front-left,front-right,rear-left,rear-right
priority = 100
direction = output

[Mapping builtin-mic]
description = Built-in Mic
device-strings = front:%f
paths-output = builtin-mic-input
channel-map = left,center,right
priority = 100
direction = input

[Mapping codec-output]
description = Headphone
device-strings = front:%f,1
paths-output = codec-output
channel-map = left,right
priority = 100
direction = output

[Mapping codec-input]
description = Headphone Mic
device-strings = front:%f,1
paths-output = codec-input
channel-map = mono
priority = 100
direction = input

[Profile output:builtin-speaker+input:builtin-mic]
description = Built-in Speaker + Built-in Mic
output-mappings = builtin-speaker
input-mappings = builtin-mic
skip-probe = yes

[Profile output:codec-output+input:builtin-mic]
description = Headphones + Built-in Mic
output-mappings = codec-output
input-mappings = builtin-mic

[Profile output:codec-output+input:codec-input]
description = Headphones + External Mic
output-mappings = codec-output
input-mappings = codec-input

[Profile output:builtin-speaker+input:codec-input]
description = Built-in Speaker + External Mic
output-mappings = builtin-speaker
input-mappings = codec-input

AppleT2.conf

<confdir:pcm/front.conf>
<confdir:pcm/surround40.conf>

AppleT2.pcm.default {
	@args [ CARD ]
	@args.CARD {
		type string
	}

	type asym
	playback.pcm {
		type plug
		slave.pcm {
			type hw
			card $CARD
			device 0
		}
	}
	capture.pcm {
		type plug
		slave.pcm {
			type hw
			card $CARD
			device 1
		}
	}
	hint.device_output 0
	hint.device_input 1
}

AppleT2.pcm.front.0 {
	@args [ CARD ]
	@args.CARD {
		type string
	}
	type asym
	playback.pcm {
		type hw
		card $CARD
		device 0
	}
	capture.pcm {
		type hw
		card $CARD
		device 1
	}
	hint.device_output 0
	hint.device_input 1
}
AppleT2.pcm.front.1 {
	@args [ CARD ]
	@args.CARD {
		type string
	}
	type asym
	playback.pcm {
		type hw
		card $CARD
		device 2
	}
	capture.pcm {
		type hw
		card $CARD
		device 3
	}
	hint.device_output 2
	hint.device_input 3
}
AppleT2.pcm.front.2 {
	@args [ CARD ]
	@args.CARD {
		type string
	}
	type hw
	card $CARD
	device 4
}

Are there any updates that might work with Pop!_OS since it now uses pipewire instead of pulseaudio?

https://wiki.t2linux.org/guides/audio-config/#using-pipewire-instead-of-pulseaudio the change here to 91-pulseaudio-custom.rules should work.