Re: [PATCH] ALSA: hda/conexant: Fix microphone mute after power-on reboot

[Takashi Iwai]

On Wed, 01 Jul 2026 10:18:00 +0200,
os_dengxiang82 wrote:
> 
> 
> Hi Takashi,
> 
>   This failure occurs during bootup as well as after runtime resume. Does
> runtime resume here refer to the resume handler, like .resume = cx_resume? or
> something else? Looking forward to your reply.

It's hda_codec_runtime_resume().  We have no Conexant-specific resume
callback, hence the standard procedure is applied, i.e.
regcache_mark_dirty() and snd_hda_regmap_sync() make the codec verbs
resumed that have been touched.  So, you'd need to check whether the
needed amp has been already accessed via regmap, and check whether the
value gets restored properly in the procedure above.


Takashi

> 
> xiang
> 
> At 2026-07-01 15:37:22, "Takashi Iwai" <tiwai@xxxxxxx> wrote:
> >On Wed, 01 Jul 2026 08:55:33 +0200,
> >dengxiang wrote:
> >> 
> >> Some devices have mute settings in their firmware set by the factory.
> >> This is to stop popping noise when the devices turn on. But this setting
> >> makes the microphones unable to record sound properly. This patch
> >> solves this problem and is compatible with conexant chips.
> >> 
> >> Signed-off-by: dengxiang <os_dengxiang82@xxxxxxx>
> >
> >Hmm, this doesn't look like a right solution.
> >
> >Is it only the problem after the boot?  Or is it an issue after the
> >runtime PM suspend?  The amp value must be restored by the runtime
> >resume, and if this doesn't work expected, it's a thing to be
> >addressed there, not in the PCM hook at all.
> >
> >
> >thanks,
> >
> >Takashi
> >
> >> ---
> >>  sound/hda/codecs/conexant.c | 21 +++++++++++++++++++++
> >>  1 file changed, 21 insertions(+)
> >> 
> >> diff --git a/sound/hda/codecs/conexant.c b/sound/hda/codecs/conexant.c
> >> index 3d92262763f6..3229f9ef5969 100644
> >> --- a/sound/hda/codecs/conexant.c
> >> +++ b/sound/hda/codecs/conexant.c
> >> @@ -1184,6 +1184,24 @@ static void add_cx5051_fake_mutes(struct hda_codec *codec)
> >>                    spec->gen.dac_min_mute = true;
> >>  }
> >>  
> >> +static void cxt_fixed_mic_boost(struct hda_codec *codec, hda_nid_t node_id)
> >> +{
> >> +                  struct conexant_spec *spec = codec->spec;
> >> +                  unsigned int value = 0;
> >> +
> >> +                  value = snd_hda_codec_read(codec, node_id, 0, AC_VERB_GET_AMP_GAIN_MUTE, 0);
> >> +                  snd_hda_codec_amp_stereo(codec, node_id, HDA_INPUT, 0, HDA_AMP_VOLMASK, value);
> >> +}
> >> +
> >> +static void cxt_capture_hook(struct hda_pcm_stream *hinfo,  struct hda_codec *codec,
> >> +                                                                     struct snd_pcm_substream *substream, int action)
> >> +{
> >> +                  struct conexant_spec *spec = codec->spec;
> >> +                  hda_nid_t mux_pin = spec->gen.imux_pins[spec->gen.cur_mux[0]];
> >> +
> >> +                  cxt_fixed_mic_boost(codec, mux_pin);
> >> +}
> >> +
> >>  static int cx_probe(struct hda_codec *codec, const struct hda_device_id *id)
> >>  {
> >>                    struct conexant_spec *spec;
> >> @@ -1271,6 +1289,9 @@ static int cx_probe(struct hda_codec *codec, const struct hda_device_id *id)
> >>                    if (err < 0)
> >>                                          goto error;
> >>  
> >> +                  if (spec->gen.pcm_capture_hook == NULL)
> >> +                                        spec->gen.pcm_capture_hook = cxt_capture_hook;
> >> +
> >>                    /* Some laptops with Conexant chips show stalls in S3 resume,
> >>                     * which falls into the single-cmd mode.
> >>                     * Better to make reset, then.
> >> -- 
> >> 2.39.5
> >>
>