diff --git a/sound/pci/ac97/ac97_patch.c b/sound/pci/ac97/ac97_patch.c index 39198e505b12aabacd6842389647da8dff2c7c68..2da89810ca10fbab1e440aa4a0ae282e61799c42 100644 --- a/sound/pci/ac97/ac97_patch.c +++ b/sound/pci/ac97/ac97_patch.c @@ -3446,6 +3446,7 @@ static const struct snd_kcontrol_new snd_ac97_controls_vt1617a[] = { int patch_vt1617a(struct snd_ac97 * ac97) { int err = 0; + int val; /* we choose to not fail out at this point, but we tell the caller when we return */ @@ -3456,7 +3457,13 @@ int patch_vt1617a(struct snd_ac97 * ac97) /* bring analog power consumption to normal by turning off the * headphone amplifier, like WinXP driver for EPIA SP */ - snd_ac97_write_cache(ac97, 0x5c, 0x20); + /* We need to check the bit before writing it. + * On some (many?) hardwares, setting bit actually clears it! + */ + val = snd_ac97_read(ac97, 0x5c); + if (!(val & 0x20)) + snd_ac97_write_cache(ac97, 0x5c, 0x20); + ac97->ext_id |= AC97_EI_SPDIF; /* force the detection of spdif */ ac97->rates[AC97_RATES_SPDIF] = SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000; ac97->build_ops = &patch_vt1616_ops;