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git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
ALSA: hda/generic: Add a helper to mute speakers at suspend/shutdown
Some devices indicate click noises at suspend or shutdown when the
speakers are unmuted. This patch adds a helper,
snd_hda_gen_shutup_speakers(), to work around it. The new function is
supposed to be called at suspend or shutdown by the codec driver, and
it mutes the speakers.
The mute status isn't cached, hence the original mute state will be
restored at resume again.
Link: https://patch.msgid.link/20240726142625.2460-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
+64
+63
sound/pci/hda/hda_generic.c
+63
sound/pci/hda/hda_generic.c
···
4955
4955
}
4956
4956
EXPORT_SYMBOL_GPL(snd_hda_gen_stream_pm);
4957
4957
4958
+
/* forcibly mute the speaker output without caching; return true if updated */
4959
+
static bool force_mute_output_path(struct hda_codec *codec, hda_nid_t nid)
4960
+
{
4961
+
if (!nid)
4962
+
return false;
4963
+
if (!nid_has_mute(codec, nid, HDA_OUTPUT))
4964
+
return false; /* no mute, skip */
4965
+
if (snd_hda_codec_amp_read(codec, nid, 0, HDA_OUTPUT, 0) &
4966
+
snd_hda_codec_amp_read(codec, nid, 1, HDA_OUTPUT, 0) &
4967
+
HDA_AMP_MUTE)
4968
+
return false; /* both channels already muted, skip */
4969
+
4970
+
/* direct amp update without caching */
4971
+
snd_hda_codec_write(codec, nid, 0, AC_VERB_SET_AMP_GAIN_MUTE,
4972
+
AC_AMP_SET_OUTPUT | AC_AMP_SET_LEFT |
4973
+
AC_AMP_SET_RIGHT | HDA_AMP_MUTE);
4974
+
return true;
4975
+
}
4976
+
4977
+
/**
4978
+
* snd_hda_gen_shutup_speakers - Forcibly mute the speaker outputs
4979
+
* @codec: the HDA codec
4980
+
*
4981
+
* Forcibly mute the speaker outputs, to be called at suspend or shutdown.
4982
+
*
4983
+
* The mute state done by this function isn't cached, hence the original state
4984
+
* will be restored at resume.
4985
+
*
4986
+
* Return true if the mute state has been changed.
4987
+
*/
4988
+
bool snd_hda_gen_shutup_speakers(struct hda_codec *codec)
4989
+
{
4990
+
struct hda_gen_spec *spec = codec->spec;
4991
+
const int *paths;
4992
+
const struct nid_path *path;
4993
+
int i, p, num_paths;
4994
+
bool updated = false;
4995
+
4996
+
/* if already powered off, do nothing */
4997
+
if (!snd_hdac_is_power_on(&codec->core))
4998
+
return false;
4999
+
5000
+
if (spec->autocfg.line_out_type == AUTO_PIN_SPEAKER_OUT) {
5001
+
paths = spec->out_paths;
5002
+
num_paths = spec->autocfg.line_outs;
5003
+
} else {
5004
+
paths = spec->speaker_paths;
5005
+
num_paths = spec->autocfg.speaker_outs;
5006
+
}
5007
+
5008
+
for (i = 0; i < num_paths; i++) {
5009
+
path = snd_hda_get_path_from_idx(codec, paths[i]);
5010
+
if (!path)
5011
+
continue;
5012
+
for (p = 0; p < path->depth; p++)
5013
+
if (force_mute_output_path(codec, path->path[p]))
5014
+
updated = true;
5015
+
}
5016
+
5017
+
return updated;
5018
+
}
5019
+
EXPORT_SYMBOL_GPL(snd_hda_gen_shutup_speakers);
5020
+
4958
5021
/**
4959
5022
* snd_hda_gen_parse_auto_config - Parse the given BIOS configuration and
4960
5023
* set up the hda_gen_spec