[alsa-devel] hda question: 'Headphone Playback Switch' cannot unmute the pin's output amplifier?

Lin, Mengdong mengdong.lin at intel.com
Wed Jun 5 13:06:00 CEST 2013


I'm using a Realtek HD-A codec ALC282. But the headphone output amplifier is always muted and I cannot unmute it by amixer.

I tried to unmute the pin via control 'Headphone Playback Switch', but snd_hda_mixer_amp_switch_put() gets a ZERO value from ucontrol->value.integer.value, thus the pin will be muted.
Could somebody give me some tips to further check this issue? Many thanks!

Here are the headphone pin info:
Node 0x21 [Pin Complex] wcaps 0x40058d: Stereo Amp-Out
  Control: name="Headphone Playback Switch", index=0, device=0
    ControlAmp: chs=3, dir=Out, idx=0, ofs=0
  Control: name="Headphone Jack", index=0, device=0
  Amp-Out caps: ofs=0x00, nsteps=0x00, stepsize=0x00, mute=1
  Amp-Out vals:  [0x80 0x80]
  Pincap 0x0000001c: OUT HP Detect
  Pin Default 0x0321401f: [Jack] HP Out at Ext Left
    Conn = 1/8, Color = Green
    DefAssociation = 0x1, Sequence = 0xf
  Pin-ctls: 0xc0: OUT HP
  Unsolicited: tag=01, enabled=1
  Power states:  D0 D1 D2 D3 EPSS
  Power: setting=D0, actual=D0
  Connection: 2
     0x0c 0x0d*

Here is the pin's controls listed by amixer:
numid=2,iface=MIXER,name='Headphone Playback Switch'

Then I use this command to unmute the pin's amplifier:
amixer -c 1 cset numid=2,iface=MIXER,name='Headphone Playback Switch' on

My debug message show that snd_hda_mixer_amp_switch_put() gets zero value , indicating to 'mute':
[  346.263519] snd_hda_mixer_amp_switch_put: nid 0x0021, chs 3, control value [0x00000000, 0x00000000]
[  346.263527] snd_hda_codec_amp_update: nid 0x0021
[  346.263532] codec_amp_update: nid 0x0021, ch 0, direction 1 (OUT 1), index 0, val 0x00000080
[  346.263536] codec_amp_update: amp val not change
[  346.263538] snd_hda_codec_amp_update: nid 0x0021
[  346.263542] codec_amp_update: nid 0x0021, ch 1, direction 1 (OUT 1), index 0, val 0x00000080
[  346.263544] codec_amp_update: amp val not change


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