kernel-packages team mailing list archive

[mengdong <mengdong.lin@xxxxxxxxx>]

It can be ensured that HDA codec pins refer to physical outputs.

Intel display audio HW owner confirmed that there are fixed mappings between audio codec pins and GPU ports, like this:
1st Pin (NID 5) = Port B
2nd Pin (NID 6) = Port C
3rd Pin (NID 7) = Port D
No matter Gfx driver connects what transcoder to a port, the above pin/port mapping won't change. 

And since the connections between port and physical output are fixed for
a specific machine. Thus HD-A codec pins always refer to fixed physical
outputs of a machine.

So BIOS should always program a pin's 'Configuration Default' according to the actual usage of its mapped port.
Eg. If a port is physically connected to a DP/HDMI output on a machine board, the pin's "Port Connectivity" should be 00b (Jack).

-- 
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1183125

Title:
  Haswell: Ensuring HDA codec pins refer to physical outputs

Status in intel:
  New
Status in System76:
  In Progress
Status in “linux” package in Ubuntu:
  Incomplete
Status in “linux” source package in Quantal:
  In Progress
Status in “linux” source package in Raring:
  In Progress

Bug description:
  From David's email:

  http://mailman.alsa-project.org/pipermail/alsa-
  devel/2013-May/062105.html

  The HDA driver assumes that a codec pin widget node always refers to the 
  same physical output. With Haswell, it seems like this is not guaranteed 
  to be true. I would like to see this fixed on the graphics side. If not, 
  I don't know how to work around it on the audio side.

  The problems that occur on the audio side are:

    1) Some BIOSes set default pin config. E g, if the machine has a 
  single HDMI out, it can set two of the codec pins to "not connected" and 
  let the third remain "jack". As a result, the HDA driver will ignore the 
  two codec pins and only enable the third. As such, HDMI audio will not 
  work correctly, unless it's the third codec pin that is connected to the 
  physical output.

    2) Saving and restoring mutes, volumes etc is done on a per-pin basis. 
  E g, imagine that a user has a dual monitor setup and always wants audio 
  output from the left side monitor, and keep the right side monitor 
  silent. If it is not reliable which codec pin refers to which physical 
  output, one day suddenly the sound might come out on the right side 
  monitor instead.

To manage notifications about this bug go to:
https://bugs.launchpad.net/intel/+bug/1183125/+subscriptions