On 05/23/2017 04:20 PM, Tanu Kaskinen wrote:
On Tue, 2017-05-23 at 11:04 +0800, Hui Wang wrote:
On 05/20/2017 10:51 PM, Tanu Kaskinen wrote:
On Fri, 2017-05-19 at 09:29 +0800, Hui Wang wrote:
Hello Tanu,

Could you please help take a look at this patch? This patch really fix
an issue on some Dell machines (with realtek codec and has no internal
microphone on them), And I think this minor change will not introduce
regression, it is pretty safe.
The patch only changes the order in which headset-mic and headphone-mic
are listed, and that order should not have any real impact on anything.
There's clearly a bug somewhere, but the bug can't be that the paths
are listed in the wrong order, since the order should not matter.
Yes, you are right. In theory, the headset-mic and headphone-mic have
the same priority, so exchanging their order should not have any real
impact on anything.

But in practice, this bug exposes that in some situation( when there are
only headphone-mic and headset-mic, and neither of them is plugged in.),
the headphone-mic is not suitable to be the default active_port.  So do
you think if it is acceptable that I don't exchange their order, I just
adjust their priorities to make the headset-mic's priority a bit higher
than headphone-mic's?
If I understand correctly, headphones and headsets only work with the
headset-mic port, and microphones only work with the headphone-mic
port. Since it's more likely that a user plugs in headphones or a
headset than a microphone, I think it's ok to make the headset-mic
priority a bit higher than headphone-mic.
There is only one audio jack, users can plug headphone, headset or microphone into it. On some Dell machines which has realtek codec, the codec/audio jack can't distinguish from hardware perspective what devices the user plugged in, so users need to do a choice from UI program:

When user plug in a headphone and select the headphone, the UI program will set the headphone to be the active_port of pa_sink, and kernel audio driver (patch_reaktek) will configure the codec to make that audio jack work as a headphone jack

When user plug in a headset and select the headset-mic, the UI program will set the headphone to be the active_port of pa_sink and set the headset-mic to be the active_port of pa_source, and kernel driver will configure the audio jack to be the headset jack


When user plug in a microphone and select the headphone-mic, the UI program will set the headphone-mic to be the active_port of pa_source, and kernel driver will configure the audio jack to be the microphone jack, then this jack can't work with headphone.


However, that still doesn't fix the bug properly, I think. What if the
user plugs in a microphone and selects it in the UI? What will make
pulseaudio switch to the headphone-mic?
The UI program will do that. The UI program will call pa_context_set_source_port_by_index() to do that.
  What will make pulseaudio
switch to the headset-mic port if headphones or a headset is plugged in
later?
This problem does not exist, since there is only one physical jack, if user want to plug headset or headphone, he need to unplug the microphone first. After user plug in the headphone or headset, the UI program will call pa_context_set_source/sink_port_by_index() to set active port according to user's choice.



It sounds like the kernel might be buggy too. Why does it have to
disable headphone output if pulseaudio's active source port happens to
be headphone-mic?
It is not a bug, some realtek codec can configure a port (pins) to be input or output, that means a physical jack can be configured as headphone jack or microphone jack.

When headphone-mic is active source port, the audio driver only disable the headphone shared the same port with this headphone-mic, the kernel driver doesn't disable other headphones.
The kernel seems to select from two mic modes:
headset or microphone, but I don't understand why it doesn't have a
mode for no mic input at all, which could be used when headphones are
plugged in.

For most cases (almost 99.999% cases), the output choice and input choice doesn't impact each other. This problem only happens on some dell machines, which has realtek codec, and has a physical audio jack to support headphone, headset or microphone, and the codec has no hardware ability to distinguish devices.


_______________________________________________
pulseaudio-discuss mailing list
pulseaudio-discuss@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/pulseaudio-discuss

Reply via email to