Re: [PATCH 4.19 096/139] ALSA: hda/realtek - fix the pop noise on headphone for lenovo laptops

From: Thomas Zeitlhofer
Date: Wed Dec 12 2018 - 18:45:24 EST


On Tue, Dec 04, 2018 at 11:49:37AM +0100, Greg Kroah-Hartman wrote:
> 4.19-stable review patch. If anyone has any objections, please let me
> know.
> ------------------
> From: Hui Wang <>
> commit c4cfcf6f4297c9256b53790bacbbbd6901fef468 upstream.
> We have several Lenovo laptops with the codec alc285, when playing
> sound via headphone, we can hear click/pop noise in the headphone, if
> we let the headphone share the DAC of NID 0x2 with the speaker, the
> noise disappears.
> The Lenovo laptops here include P52, P72, X1 yoda2 and X1 carbon.

on a current Thinkpad X1 Yoga, this breaks the LED functionality on the
audio- and mic-mute buttons. While the buttons still work, the LEDs are
permanently off and do not reflect the mute state any more.

Reverting this patch restores the LED functionality.

Here, even without this patch, there is no click/pop noise noticeable
when using headphones.