Recently we tested the headphone playback on 2 LG machines, if we set
the volume to the max value or near to the max value, the sound is too
loud, it could even bring harm to listeners.
A workaround is to decrease the max volume to a reasonable value for
the headphone's amplifier, then the users couldn't set the volume
bigger than that value from the userspace.
Signed-off-by: Hui Wang <hui.wang@xxxxxxxxxxxxx>
---
sound/pci/hda/patch_realtek.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)
diff --git a/sound/pci/hda/patch_realtek.c b/sound/pci/hda/patch_realtek.c
index e904f62e1952..d463d416fc23 100644
--- a/sound/pci/hda/patch_realtek.c
+++ b/sound/pci/hda/patch_realtek.c
@@ -6964,6 +6964,25 @@ static void alc256_fixup_mic_no_presence_and_resume(struct hda_codec *codec,
}
}
+static void alc256_decrease_headphone_amp_val(struct hda_codec *codec,
+ const struct hda_fixup *fix, int action)
+{
+ u32 caps;
+ u8 nsteps, offs;
+
+ if (action != HDA_FIXUP_ACT_PRE_PROBE)
+ return;
+
+ caps = query_amp_caps(codec, 0x3, HDA_OUTPUT);
+ nsteps = ((caps & AC_AMPCAP_NUM_STEPS) >> AC_AMPCAP_NUM_STEPS_SHIFT) - 10;
+ offs = ((caps & AC_AMPCAP_OFFSET) >> AC_AMPCAP_OFFSET_SHIFT) - 10;
+ caps &= ~AC_AMPCAP_NUM_STEPS & ~AC_AMPCAP_OFFSET;
+ caps |= (nsteps << AC_AMPCAP_NUM_STEPS_SHIFT) | (offs << AC_AMPCAP_OFFSET_SHIFT);
+
+ if (snd_hda_override_amp_caps(codec, 0x3, HDA_OUTPUT, caps))
+ codec_warn(codec, "failed to override amp caps for NID 0x3\n");
+}
+
static void alc_fixup_dell4_mic_no_presence_quiet(struct hda_codec *codec,
const struct hda_fixup *fix,
int action)
@@ -7382,6 +7401,7 @@ enum {
ALC294_FIXUP_CS35L41_I2C_2,
ALC245_FIXUP_CS35L56_SPI_4_HP_GPIO_LED,
ALC256_FIXUP_ACER_SFG16_MICMUTE_LED,
+ ALC256_FIXUP_HEADPHONE_AMP_VOL,
};
/* A special fixup for Lenovo C940 and Yoga Duet 7;
@@ -9581,6 +9601,10 @@ static const struct hda_fixup alc269_fixups[] = {
.type = HDA_FIXUP_FUNC,
.v.func = alc256_fixup_acer_sfg16_micmute_led,
},
+ [ALC256_FIXUP_HEADPHONE_AMP_VOL] = {
+ .type = HDA_FIXUP_FUNC,
+ .v.func = alc256_decrease_headphone_amp_val,
+ },
};
static const struct snd_pci_quirk alc269_fixup_tbl[] = {
@@ -10319,6 +10343,8 @@ static const struct snd_pci_quirk alc269_fixup_tbl[] = {
SND_PCI_QUIRK(0x17aa, 0x9e56, "Lenovo ZhaoYang CF4620Z", ALC286_FIXUP_SONY_MIC_NO_PRESENCE),
SND_PCI_QUIRK(0x1849, 0x1233, "ASRock NUC Box 1100", ALC233_FIXUP_NO_AUDIO_JACK),
SND_PCI_QUIRK(0x1849, 0xa233, "Positivo Master C6300", ALC269_FIXUP_HEADSET_MIC),
+ SND_PCI_QUIRK(0x1854, 0x0440, "LG CQ6", ALC256_FIXUP_HEADPHONE_AMP_VOL),
+ SND_PCI_QUIRK(0x1854, 0x0441, "LG CQ6 AIO", ALC256_FIXUP_HEADPHONE_AMP_VOL),
SND_PCI_QUIRK(0x19e5, 0x3204, "Huawei MACH-WX9", ALC256_FIXUP_HUAWEI_MACH_WX9_PINS),
SND_PCI_QUIRK(0x19e5, 0x320f, "Huawei WRT-WX9 ", ALC256_FIXUP_ASUS_MIC_NO_PRESENCE),
SND_PCI_QUIRK(0x1b35, 0x1235, "CZC B20", ALC269_FIXUP_CZC_B20),
--
2.34.1
