ASoC: Docs: update DAPM
Update the DAPM documentation and bring it up to date with the current code base. This includes API changes and new widgets. Signed-off-by: Liam Girdwood <liam.r.girdwood@linux.intel.com> Signed-off-by: Mark Brown <broonie@linaro.org>
This commit is contained in:
Liam Girdwood
Mark Brown
parent
3eb012834b
commit
630a1b3b4f
|
|
@ -21,7 +21,7 @@ level power systems.
|
|||
|
||||
There are 4 power domains within DAPM
|
||||
|
||||
1. Codec domain - VREF, VMID (core codec and audio power)
|
||||
1. Codec bias domain - VREF, VMID (core codec and audio power)
|
||||
Usually controlled at codec probe/remove and suspend/resume, although
|
||||
can be set at stream time if power is not needed for sidetone, etc.
|
||||
|
||||
|
|
@ -63,14 +63,22 @@ Audio DAPM widgets fall into a number of types:-
|
|||
o Line - Line Input/Output (and optional Jack)
|
||||
o Speaker - Speaker
|
||||
o Supply - Power or clock supply widget used by other widgets.
|
||||
o Regulator - External regulator that supplies power to audio components.
|
||||
o Clock - External clock that supplies clock to audio componnents.
|
||||
o AIF IN - Audio Interface Input (with TDM slot mask).
|
||||
o AIF OUT - Audio Interface Output (with TDM slot mask).
|
||||
o Siggen - Signal Generator.
|
||||
o DAI IN - Digital Audio Interface Input.
|
||||
o DAI OUT - Digital Audio Interface Output.
|
||||
o DAI Link - DAI Link between two DAI structures */
|
||||
o Pre - Special PRE widget (exec before all others)
|
||||
o Post - Special POST widget (exec after all others)
|
||||
|
||||
(Widgets are defined in include/sound/soc-dapm.h)
|
||||
|
||||
Widgets are usually added in the codec driver and the machine driver. There are
|
||||
convenience macros defined in soc-dapm.h that can be used to quickly build a
|
||||
list of widgets of the codecs and machines DAPM widgets.
|
||||
Widgets can be added to the sound card by any of the component driver types.
|
||||
There are convenience macros defined in soc-dapm.h that can be used to quickly
|
||||
build a list of widgets of the codecs and machines DAPM widgets.
|
||||
|
||||
Most widgets have a name, register, shift and invert. Some widgets have extra
|
||||
parameters for stream name and kcontrols.
|
||||
|
|
@ -80,11 +88,13 @@ parameters for stream name and kcontrols.
|
|||
-------------------------
|
||||
|
||||
Stream Widgets relate to the stream power domain and only consist of ADCs
|
||||
(analog to digital converters) and DACs (digital to analog converters).
|
||||
(analog to digital converters), DACs (digital to analog converters),
|
||||
AIF IN and AIF OUT.
|
||||
|
||||
Stream widgets have the following format:-
|
||||
|
||||
SND_SOC_DAPM_DAC(name, stream name, reg, shift, invert),
|
||||
SND_SOC_DAPM_AIF_IN(name, stream, slot, reg, shift, invert)
|
||||
|
||||
NOTE: the stream name must match the corresponding stream name in your codec
|
||||
snd_soc_codec_dai.
|
||||
|
|
@ -94,6 +104,11 @@ e.g. stream widgets for HiFi playback and capture
|
|||
SND_SOC_DAPM_DAC("HiFi DAC", "HiFi Playback", REG, 3, 1),
|
||||
SND_SOC_DAPM_ADC("HiFi ADC", "HiFi Capture", REG, 2, 1),
|
||||
|
||||
e.g. stream widgets for AIF
|
||||
|
||||
SND_SOC_DAPM_AIF_IN("AIF1RX", "AIF1 Playback", 0, SND_SOC_NOPM, 0, 0),
|
||||
SND_SOC_DAPM_AIF_OUT("AIF1TX", "AIF1 Capture", 0, SND_SOC_NOPM, 0, 0),
|
||||
|
||||
|
||||
2.2 Path Domain Widgets
|
||||
-----------------------
|
||||
|
|
@ -121,12 +136,14 @@ If you dont want the mixer elements prefixed with the name of the mixer widget,
|
|||
you can use SND_SOC_DAPM_MIXER_NAMED_CTL instead. the parameters are the same
|
||||
as for SND_SOC_DAPM_MIXER.
|
||||
|
||||
2.3 Platform/Machine domain Widgets
|
||||
-----------------------------------
|
||||
|
||||
2.3 Machine domain Widgets
|
||||
--------------------------
|
||||
|
||||
Machine widgets are different from codec widgets in that they don't have a
|
||||
codec register bit associated with them. A machine widget is assigned to each
|
||||
machine audio component (non codec) that can be independently powered. e.g.
|
||||
machine audio component (non codec or DSP) that can be independently
|
||||
powered. e.g.
|
||||
|
||||
o Speaker Amp
|
||||
o Microphone Bias
|
||||
|
|
@ -146,12 +163,12 @@ static int spitz_mic_bias(struct snd_soc_dapm_widget* w, int event)
|
|||
SND_SOC_DAPM_MIC("Mic Jack", spitz_mic_bias),
|
||||
|
||||
|
||||
2.4 Codec Domain
|
||||
----------------
|
||||
2.4 Codec (BIAS) Domain
|
||||
-----------------------
|
||||
|
||||
The codec power domain has no widgets and is handled by the codecs DAPM event
|
||||
handler. This handler is called when the codec powerstate is changed wrt to any
|
||||
stream event or by kernel PM events.
|
||||
The codec bias power domain has no widgets and is handled by the codecs DAPM
|
||||
event handler. This handler is called when the codec powerstate is changed wrt
|
||||
to any stream event or by kernel PM events.
|
||||
|
||||
|
||||
2.5 Virtual Widgets
|
||||
|
|
@ -169,15 +186,16 @@ After all the widgets have been defined, they can then be added to the DAPM
|
|||
subsystem individually with a call to snd_soc_dapm_new_control().
|
||||
|
||||
|
||||
3. Codec Widget Interconnections
|
||||
================================
|
||||
3. Codec/DSP Widget Interconnections
|
||||
====================================
|
||||
|
||||
Widgets are connected to each other within the codec and machine by audio paths
|
||||
(called interconnections). Each interconnection must be defined in order to
|
||||
create a map of all audio paths between widgets.
|
||||
Widgets are connected to each other within the codec, platform and machine by
|
||||
audio paths (called interconnections). Each interconnection must be defined in
|
||||
order to create a map of all audio paths between widgets.
|
||||
|
||||
This is easiest with a diagram of the codec (and schematic of the machine audio
|
||||
system), as it requires joining widgets together via their audio signal paths.
|
||||
This is easiest with a diagram of the codec or DSP (and schematic of the machine
|
||||
audio system), as it requires joining widgets together via their audio signal
|
||||
paths.
|
||||
|
||||
e.g., from the WM8731 output mixer (wm8731.c)
|
||||
|
||||
|
|
@ -247,16 +265,9 @@ machine and includes the codec. e.g.
|
|||
o Mic Jack
|
||||
o Codec Pins
|
||||
|
||||
When a codec pin is NC it can be marked as not used with a call to
|
||||
|
||||
snd_soc_dapm_set_endpoint(codec, "Widget Name", 0);
|
||||
|
||||
The last argument is 0 for inactive and 1 for active. This way the pin and its
|
||||
input widget will never be powered up and consume power.
|
||||
|
||||
This also applies to machine widgets. e.g. if a headphone is connected to a
|
||||
jack then the jack can be marked active. If the headphone is removed, then
|
||||
the headphone jack can be marked inactive.
|
||||
Endpoints are added to the DAPM graph so that their usage can be determined in
|
||||
order to save power. e.g. NC codecs pins will be switched OFF, unconnected
|
||||
jacks can also be switched OFF.
|
||||
|
||||
|
||||
5 DAPM Widget Events
|
||||
|
|
|
|||
Loading…
Reference in New Issue