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Diffstat (limited to 'Documentation/sound/alsa/HD-Audio-DP-MST-audio.txt')
| -rw-r--r-- | Documentation/sound/alsa/HD-Audio-DP-MST-audio.txt | 74 |
1 files changed, 0 insertions, 74 deletions
diff --git a/Documentation/sound/alsa/HD-Audio-DP-MST-audio.txt b/Documentation/sound/alsa/HD-Audio-DP-MST-audio.txt deleted file mode 100644 index 82744ac3513d..000000000000 --- a/Documentation/sound/alsa/HD-Audio-DP-MST-audio.txt +++ /dev/null @@ -1,74 +0,0 @@ -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 -======================== |