[PATCH 0/3] Properly fix headphone noise on the XPS 13 and other ALC256 devices

[Takashi Iwai]

On Mon, 30 Mar 2020 09:30:29 +0200,
Thomas Hebb wrote:
> 
> 
> The root cause of various pervasive audio problems on the XPS 13
> 9350/9360, mostly relating to the headphone jack, turns out to be an
> undocumented feature of the ALC256 and similar codecs that routes audio
> along paths not exposed in the HDA node graph. The best we've had so far
> to configure this feature is magic numbers provided by Realtek, none of
> which have fully fixed all issues.
> 
> This series documents the "PC Beep Hidden Register", which controls the
> feature and which I've reverse engineered using black box techniques,
> and uses my findings to hopefully fix the headphone issues on my XPS 13
> once and for all.

Thanks for the patches, all those look interesting and good to apply.
But I'd like to get it reviewed by Kailang at first -- in case we
might be playing with something untouchable.

Kailang, could you review this quickly?


Takashi

> 
> Thomas Hebb (3):
>   ALSA: doc: Document PC Beep Hidden Register on Realtek ALC256
>   ALSA: hda/realtek - Set principled PC Beep configuration for ALC256
>   ALSA: hda/realtek - Remove now-unnecessary XPS 13 headphone noise
>     fixups
> 
>  Documentation/sound/hd-audio/index.rst        |   1 +
>  Documentation/sound/hd-audio/models.rst       |   2 -
>  .../sound/hd-audio/realtek-pc-beep.rst        | 129 ++++++++++++++++++
>  sound/pci/hda/patch_realtek.c                 |  49 ++-----
>  4 files changed, 139 insertions(+), 42 deletions(-)
>  create mode 100644 Documentation/sound/hd-audio/realtek-pc-beep.rst
> 
> -- 
> 2.25.2
>