75 lines
2.2 KiB
Plaintext
75 lines
2.2 KiB
Plaintext
|
To support DP MST audio, HD Audio hdmi codec driver introduces virtual pin
|
||
|
and dynamic pcm assignment.
|
||
|
|
||
|
Virtual pin is an extension of per_pin. The most difference of DP MST
|
||
|
from legacy is that DP MST introduces device entry. Each pin can contain
|
||
|
several device entries. Each device entry behaves as a pin.
|
||
|
|
||
|
As each pin may contain several device entries and each codec may contain
|
||
|
several pins, if we use one pcm per per_pin, there will be many PCMs.
|
||
|
The new solution is to create a few PCMs and to dynamically bind pcm to
|
||
|
per_pin. Driver uses spec->dyn_pcm_assign flag to indicate whether to use
|
||
|
the new solution.
|
||
|
|
||
|
PCM
|
||
|
===
|
||
|
To be added
|
||
|
|
||
|
|
||
|
Jack
|
||
|
====
|
||
|
|
||
|
Presume:
|
||
|
- MST must be dyn_pcm_assign, and it is acomp (for Intel scenario);
|
||
|
- NON-MST may or may not be dyn_pcm_assign, it can be acomp or !acomp;
|
||
|
|
||
|
So there are the following scenarios:
|
||
|
a. MST (&& dyn_pcm_assign && acomp)
|
||
|
b. NON-MST && dyn_pcm_assign && acomp
|
||
|
c. NON-MST && !dyn_pcm_assign && !acomp
|
||
|
|
||
|
Below discussion will ignore MST and NON-MST difference as it doesn't
|
||
|
impact on jack handling too much.
|
||
|
|
||
|
Driver uses struct hdmi_pcm pcm[] array in hdmi_spec and snd_jack is
|
||
|
a member of hdmi_pcm. Each pin has one struct hdmi_pcm * pcm pointer.
|
||
|
|
||
|
For !dyn_pcm_assign, per_pin->pcm will assigned to spec->pcm[n] statically.
|
||
|
|
||
|
For dyn_pcm_assign, per_pin->pcm will assigned to spec->pcm[n]
|
||
|
when monitor is hotplugged.
|
||
|
|
||
|
|
||
|
Build Jack
|
||
|
----------
|
||
|
|
||
|
- dyn_pcm_assign
|
||
|
Will not use hda_jack but use snd_jack in spec->pcm_rec[pcm_idx].jack directly.
|
||
|
|
||
|
- !dyn_pcm_assign
|
||
|
Use hda_jack and assign spec->pcm_rec[pcm_idx].jack = jack->jack statically.
|
||
|
|
||
|
|
||
|
Unsolicited Event Enabling
|
||
|
--------------------------
|
||
|
Enable unsolicited event if !acomp.
|
||
|
|
||
|
|
||
|
Monitor Hotplug Event Handling
|
||
|
------------------------------
|
||
|
- acomp
|
||
|
pin_eld_notify() -> check_presence_and_report() -> hdmi_present_sense() ->
|
||
|
sync_eld_via_acomp().
|
||
|
Use directly snd_jack_report() on spec->pcm_rec[pcm_idx].jack for
|
||
|
both dyn_pcm_assign and !dyn_pcm_assign
|
||
|
|
||
|
- !acomp
|
||
|
Hdmi_unsol_event() -> hdmi_intrinsic_event() -> check_presence_and_report() ->
|
||
|
hdmi_present_sense() -> hdmi_prepsent_sense_via_verbs()
|
||
|
Use directly snd_jack_report() on spec->pcm_rec[pcm_idx].jack for dyn_pcm_assign.
|
||
|
Use hda_jack mechanism to handle jack events.
|
||
|
|
||
|
|
||
|
Others to be added later
|
||
|
========================
|