1======================================
2HD-Audio Codec-Specific Mixer Controls
3======================================
4
5
6This file explains the codec-specific mixer controls.
7
8Realtek codecs
9--------------
10
11Channel Mode
12  This is an enum control to change the surround-channel setup,
13  appears only when the surround channels are available.
14  It gives the number of channels to be used, "2ch", "4ch", "6ch",
15  and "8ch".  According to the configuration, this also controls the
16  jack-retasking of multi-I/O jacks.
17
18Auto-Mute Mode
19  This is an enum control to change the auto-mute behavior of the
20  headphone and line-out jacks.  If built-in speakers and headphone
21  and/or line-out jacks are available on a machine, this controls
22  appears.
23  When there are only either headphones or line-out jacks, it gives
24  "Disabled" and "Enabled" state.  When enabled, the speaker is muted
25  automatically when a jack is plugged.
26
27  When both headphone and line-out jacks are present, it gives
28  "Disabled", "Speaker Only" and "Line-Out+Speaker".  When
29  speaker-only is chosen, plugging into a headphone or a line-out jack
30  mutes the speakers, but not line-outs.  When line-out+speaker is
31  selected, plugging to a headphone jack mutes both speakers and
32  line-outs.
33
34
35IDT/Sigmatel codecs
36-------------------
37
38Analog Loopback
39  This control enables/disables the analog-loopback circuit.  This
40  appears only when "loopback" is set to true in a codec hint
41  (see HD-Audio.txt).  Note that on some codecs the analog-loopback
42  and the normal PCM playback are exclusive, i.e. when this is on, you
43  won't hear any PCM stream.
44
45Swap Center/LFE
46  Swaps the center and LFE channel order.  Normally, the left
47  corresponds to the center and the right to the LFE.  When this is
48  ON, the left to the LFE and the right to the center.
49
50Headphone as Line Out
51  When this control is ON, treat the headphone jacks as line-out
52  jacks.  That is, the headphone won't auto-mute the other line-outs,
53  and no HP-amp is set to the pins.
54
55Mic Jack Mode, Line Jack Mode, etc
56  These enum controls the direction and the bias of the input jack
57  pins.  Depending on the jack type, it can set as "Mic In" and "Line
58  In", for determining the input bias, or it can be set to "Line Out"
59  when the pin is a multi-I/O jack for surround channels.
60
61
62VIA codecs
63----------
64
65Smart 5.1
66  An enum control to re-task the multi-I/O jacks for surround outputs.
67  When it's ON, the corresponding input jacks (usually a line-in and a
68  mic-in) are switched as the surround and the CLFE output jacks.
69
70Independent HP
71  When this enum control is enabled, the headphone output is routed
72  from an individual stream (the third PCM such as hw:0,2) instead of
73  the primary stream.  In the case the headphone DAC is shared with a
74  side or a CLFE-channel DAC, the DAC is switched to the headphone
75  automatically.
76
77Loopback Mixing
78  An enum control to determine whether the analog-loopback route is
79  enabled or not.  When it's enabled, the analog-loopback is mixed to
80  the front-channel.  Also, the same route is used for the headphone
81  and speaker outputs.  As a side-effect, when this mode is set, the
82  individual volume controls will be no longer available for
83  headphones and speakers because there is only one DAC connected to a
84  mixer widget.
85
86Dynamic Power-Control
87  This control determines whether the dynamic power-control per jack
88  detection is enabled or not.  When enabled, the widgets power state
89  (D0/D3) are changed dynamically depending on the jack plugging
90  state for saving power consumptions.  However, if your system
91  doesn't provide a proper jack-detection, this won't work; in such a
92  case, turn this control OFF.
93
94Jack Detect
95  This control is provided only for VT1708 codec which gives no proper
96  unsolicited event per jack plug.  When this is on, the driver polls
97  the jack detection so that the headphone auto-mute can work, while
98  turning this off would reduce the power consumption.
99
100
101Conexant codecs
102---------------
103
104Auto-Mute Mode
105  See Reatek codecs.
106
107
108Analog codecs
109--------------
110
111Channel Mode
112  This is an enum control to change the surround-channel setup,
113  appears only when the surround channels are available.
114  It gives the number of channels to be used, "2ch", "4ch" and "6ch".
115  According to the configuration, this also controls the
116  jack-retasking of multi-I/O jacks.
117
118Independent HP
119  When this enum control is enabled, the headphone output is routed
120  from an individual stream (the third PCM such as hw:0,2) instead of
121  the primary stream.
122