FM / es8316

/usr/share/alsa/ucm2/codecs/es8316

Name	Size	Mode	Actions
EnableSeq.conf	649	0644	edit dl rm
HeadPhones.conf	327	0644	edit dl rm
IN1-HeadsetMic.conf	359	0644	edit dl rm
IN1-InternalMic.conf	329	0644	edit dl rm
IN2-HeadsetMic.conf	359	0644	edit dl rm
IN2-InternalMic.conf	329	0644	edit dl rm
MonoSpeaker.conf	1131	0644	edit dl rm
Speaker.conf	267	0644	edit dl rm

Edit: /usr/share/alsa/ucm2/codecs/es8316/MonoSpeaker.conf (1131B)

SectionDevice."Speaker" {
	Comment "Mono Speaker"

ConflictingDevice [
		"Headphones"
	]

EnableSequence [
		# BYT/CHT devices with an ES8316 codec use a single speaker
		# connected between the headhpone LOUT and ROUT pins, expecting
		# the output to be in a mono differential mode. Presumably this
		# is done to use the power of both the left and right headphone
		# amplifier channels to allow the speaker to be louder.
		#
		# The ES8316 codec does not have a differential output mode, but
		# we can emulate one by making both channels output the exact
		# same signal by setting the "DAC Mono Mix Switch", combined
		# with setting the "Playback Polarity" control to "R Invert",
		# which applies a 180 degrees phase inversion to the right chan.
		cset "name='DAC Mono Mix Switch' on"
		cset "name='Playback Polarity' 1"

cset "name='Speaker Switch' on"
	]

DisableSequence [
		cset "name='Speaker Switch' off"
		# DAC settings back to normal for stereo headphones output
		cset "name='Playback Polarity' 0"
		cset "name='DAC Mono Mix Switch' off"
	]

Value {
		PlaybackPriority 100
		PlaybackPCM "hw:${CardId}"
	}
}

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