Latest revision as of 15:47, 23 October 2023

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DART-MX8M Audio Record/Play

Get information on the Sound Cards

Installed devices:

# cat /proc/asound/cards
 0 [wm8904audio      ]: wm8904-audio - wm8904-audio
                      wm8904-audio

List device names for playback:

# aplay -L
null
    Discard all samples (playback) or generate zero samples (capture)
pulse
    PulseAudio Sound Server
sysdefault:CARD=wm8904audio
    wm8904-audio, 
    Default Audio Device

Audio Playback

Set PCM volume (main volume of audio codec), range :0-63

# amixer set Headphone 35

Play audio:

# aplay /usr/share/sounds/alsa/Front_Center.wav

Example:

# amixer set Headphone 35
Simple mixer control 'Headphone',0
  Capabilities: volume pswitch
  Playback channels: Front Left - Front Right
  Capture channels: Front Left - Front Right
  Limits: 0 - 63
  Front Left: 35 [56%] [-22.00dB] Playback [on]
  Front Right: 35 [56%] [-22.00dB] Playback [on]

# aplay /usr/share/sounds/alsa/Front_Center.wav
Playing WAVE '/usr/share/sounds/alsa/Front_Center.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Mono

Audio Record and Play, Line-in Jack

Set PCM volume (main volume of audio codec), range :0-63

# amixer set Headphone 35

Set L/R capture inverting mux inputs to IN2

# amixer set 'Left Capture Inverting Mux' IN2L
# amixer set 'Right Capture Inverting Mux' IN2R

Set capture input source to ADC

# amixer set 'Capture Input' ADC

Set DMIC Mux to DMIC2

# amixer set 'DMIC Mux' DMIC2

Record CD quality audio for 10 seconds into file test.wav

# arecord  -f cd -d 10 test.wav

Play the recorded file

# aplay test.wav

Example:

# amixer set Headphone 35
Simple mixer control 'Headphone',0
  Capabilities: volume pswitch
  Playback channels: Front Left - Front Right
  Capture channels: Front Left - Front Right
  Limits: 0 - 63
  Front Left: 35 [56%] [-22.00dB] Playback [on]
  Front Right: 35 [56%] [-22.00dB] Playback [on]
# amixer set 'Left Capture Inverting Mux' IN2L
Simple mixer control 'Left Capture Inverting Mux',0
  Capabilities: enum
  Items: 'IN1L' 'IN2L' 'IN3L'
  Item0: 'IN2L'
# amixer set 'Right Capture Inverting Mux' IN2R
Simple mixer control 'Right Capture Inverting Mux',0
  Capabilities: enum
  Items: 'IN1R' 'IN2R' 'IN3R'
  Item0: 'IN2R'
# amixer set 'Capture Input' ADC
Simple mixer control 'Capture Input',0
  Capabilities: enum
  Items: 'ADC' 'DMIC'
  Item0: 'ADC'
# amixer set 'DMIC Mux' DMIC2
Simple mixer control 'DMIC Mux',0
  Capabilities: enum
  Items: 'DMIC1' 'DMIC2'
  Item0: 'DMIC2'
# arecord  -f cd -d 10 test.wav
Recording WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo
# aplay test.wav
Playing WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo

Audio Record and Play, DMIC

Set Headphones volume, range :0-63

# amixer set Headphone 35

Set capture input source to DMIC

# amixer set 'Capture Input' DMIC

Set DMIC Mux to DMIC1

# amixer set 'DMIC Mux' DMIC1

Record CD quality audio for 10 seconds into file test.wav

# arecord  -f cd -d 10 test.wav

Play the recorded file

# aplay test.wav

Example:

# amixer set Headphone 35
Simple mixer control 'Headphone',0
  Capabilities: volume pswitch
  Playback channels: Front Left - Front Right
  Capture channels: Front Left - Front Right
  Limits: 0 - 63
  Front Left: 35 [56%] [-22.00dB] Playback [on]
  Front Right: 35 [56%] [-22.00dB] Playback [on]
# amixer set 'Capture Input' DMIC
Simple mixer control 'Capture Input',0
  Capabilities: enum
  Items: 'ADC' 'DMIC'
  Item0: 'DMIC'
# amixer set 'DMIC Mux' DMIC1
Simple mixer control 'DMIC Mux',0
  Capabilities: enum
  Items: 'DMIC1' 'DMIC2'
  Item0: 'DMIC1'
# arecord  -f cd -d 10 test.wav
Recording WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo
# aplay test.wav
Playing WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo

Advanced Controls

amixer without a parameter will show all available controls. For example:

# amixer
Simple mixer control 'Headphone',0
  Capabilities: volume pswitch
  Playback channels: Front Left - Front Right
  Capture channels: Front Left - Front Right
  Limits: 0 - 63
  Front Left: 35 [56%] [-22.00dB] Playback [on]
  Front Right: 35 [56%] [-22.00dB] Playback [on]
Simple mixer control 'Headphone ZC',0
  Capabilities: pswitch
  Playback channels: Front Left - Front Right
  Mono:
  Front Left: Playback [on]
  Front Right: Playback [on]
Simple mixer control 'Line Output',0
  Capabilities: volume pswitch
  Playback channels: Front Left - Front Right
  Capture channels: Front Left - Front Right
  Limits: 0 - 63
  Front Left: 57 [90%] [0.00dB] Playback [on]
  Front Right: 57 [90%] [0.00dB] Playback [on]
Simple mixer control 'Line Output ZC',0
  Capabilities: pswitch
  Playback channels: Front Left - Front Right
  Mono:
  Front Left: Playback [on]
  Front Right: Playback [on]
Simple mixer control 'Capture',0
  Capabilities: cvolume cswitch
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 31
  Front Left: Capture 24 [77%] [on]
  Front Right: Capture 24 [77%] [on]
Simple mixer control 'Capture Input',0
  Capabilities: enum
  Items: 'ADC' 'DMIC'
  Item0: 'DMIC'
...

Options:

amixer   sset sID P      set contents for one mixer simple control
amixer   sget sID        get contents for one mixer simple control

For example:

# amixer sget 'Capture'
Simple mixer control 'Capture',0
  Capabilities: cvolume cswitch
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 31
  Front Left: Capture 24 [77%] [on]
  Front Right: Capture 24 [77%] [on]
# amixer sset 'Capture' 25
Simple mixer control 'Capture',0
  Capabilities: cvolume cswitch
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 31
  Front Left: Capture 25 [81%] [on]
  Front Right: Capture 25 [81%] [on]

Capture currently now set to 81%.

Save/restore system's audio settings

alsactl store stores all alsamixer settings into a file.
Options:

  store     <card>  save current driver setup for one or each soundcards
                      to configuration file
  restore   <card>  load current driver setup for one or each soundcards
                      from configuration file

Example:

# alsactl store -f 123.conf
# alsactl restore -f 123.conf

Linux Audio record play: Difference between revisions

Latest revision as of 15:47, 23 October 2023

Contents

Get information on the Sound Cards

Audio Playback

Audio Record and Play, Line-in Jack

Audio Record and Play, DMIC

Advanced Controls

Save/restore system's audio settings

@@ Line 1: / Line 1: @@
-<!-- Set release according to "release" parameter in URL and use RELEASE_MORTY_V1.0_DART-MX8M as default
+<!-- Set release according to "release" parameter in URL and use RELEASE_SUMO_V1.0_DART-MX8M as default
---> {{#vardefine:RELEASE_PARAM|{{#urlget:release}}}} <!--
+--> {{INIT_RELEASE_PARAM|RELEASE_SUMO_V1.0_DART-MX8M}}<!--
---> {{#lst:Yocto_Platform_Customization|{{#var:RELEASE_PARAM|RELEASE_MORTY_V1.0_DART-MX8M}}}} <!--
+--> {{#lst:Yocto_Platform_Customization|{{#var:RELEASE_PARAM}}}} <!--
---> {{PageHeader|{{#var:HARDWARE_NAME}} Audio Record/Play}} {{DocImage|category1=Yocto|category2=DART-MX8M}} __toc__
+--> {{#lst:B2QT_Platform_Customization|{{#var:RELEASE_PARAM}}}} <!--
+--> {{#lst:Debian_Platform_Customization|{{#var:RELEASE_PARAM}}}} <!--
+--> {{#vardefine:SUPPORT_WM8904_DRC | <!--
+-->    {{#switch:{{#var:HARDWARE_NAME}} | <!--
+-->       DART-MX8M-PLUS = {{#ifexpr: {{#var:YOCTO_VERSION}} > 3.2 | yes | no }} | <!--
+-->       {{#ifexpr: {{#var:YOCTO_VERSION}} > 3.0 | yes | no }}  <!--
+-->    }} <!--
+--> }} <!--
+    # Add ARECORD_EXTRA_ARGS for AM62
+    # See: https://software-dl.ti.com/processor-sdk-linux/esd/AM62X/08_06_00_42/exports/docs/linux/Foundational_Components/Kernel/Kernel_Drivers/Audio.html?highlight=arecord#potential-issues
+--> {{#switch: {{#var:SOC_SERIES}}
+    | am6={{#vardefine: ARECORD_EXTRA_ARGS | -r 48000 --period-size=64}}
+    |#default=
+    }}<!--
+--> {{PageHeader|{{#var:HARDWARE_NAME}} Audio Record/Play}} {{DocImage|category1=Yocto|category2={{#var:HARDWARE_NAME}}}} __toc__
 = Get information on the Sound Cards =
 Installed devices:
 <pre>
-root@imx8m-var-dart:~# cat /proc/asound/cards
+# cat /proc/asound/cards
 [wm8904audio      ]: wm8904-audio - wm8904-audio
                        wm8904-audio
@@ Line 12: / Line 28: @@
 List device names for playback:
 <pre>
-root@imx6ul-var-dart:~# aplay -L
+# aplay -L
 null
      Discard all samples (playback) or generate zero samples (capture)
@@ Line 21: / Line 37: @@
      Default Audio Device
 </pre>
+{{#varexists:DEBIAN_NAME|
+For the upcoming, the tool amixer is used to control the audio. Please consider stopping the PulseAudio server to avoid conflicts:
+ # systemctl stop pulseaudio
+}}
 = Audio Playback =
 Set PCM volume (main volume of audio codec), range :0-63
@@ Line 33: / Line 52: @@
 Example:
 <pre>
-root@imx8m-var-dart:~# amixer set set Headphone 35
+# amixer set Headphone 35
 Simple mixer control 'Headphone',0
    Capabilities: volume pswitch
@@ Line 42: / Line 61: @@
    Front Right: 35 [56%] [-22.00dB] Playback [on]
-root@imx8m-var-dart:~# aplay /usr/share/sounds/alsa/Front_Center.wav
+# aplay /usr/share/sounds/alsa/Front_Center.wav
 Playing WAVE '/usr/share/sounds/alsa/Front_Center.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Mono
 </pre>
@@ Line 50: / Line 69: @@
 <pre>
 # amixer set Headphone 35
+</pre>
+Set L/R capture inverting mux inputs to IN2
+<pre>
+# amixer set 'Left Capture Inverting Mux' IN2L
+# amixer set 'Right Capture Inverting Mux' IN2R
 </pre>
 Set capture input source to ADC
@@ Line 60: / Line 84: @@
 </pre>
 Record CD quality audio for 10 seconds into file test.wav
-<pre>
+ # arecord {{#var:ARECORD_EXTRA_ARGS}} -f cd -d 10 test.wav
-# arecord -f cd -d 10 test.wav
-</pre>
 Play the recorded file
 <pre>
@@ Line 68: / Line 90: @@
 </pre>
 Example:
-<pre>
-root@imx8m-var-dart:~# amixer set set Headphone 35
+ # amixer set Headphone 35
-Simple mixer control 'Headphone',0
+ Simple mixer control 'Headphone',0
-  Capabilities: volume pswitch
+   Capabilities: volume pswitch
-  Playback channels: Front Left - Front Right
+   Playback channels: Front Left - Front Right
-  Capture channels: Front Left - Front Right
+   Capture channels: Front Left - Front Right
-  Limits: 0 - 63
+   Limits: 0 - 63
-  Front Left: 35 [56%] [-22.00dB] Playback [on]
+   Front Left: 35 [56%] [-22.00dB] Playback [on]
-  Front Right: 35 [56%] [-22.00dB] Playback [on]
+   Front Right: 35 [56%] [-22.00dB] Playback [on]
-root@imx8m-var-dart:~# amixer set 'Capture Input' ADC
+ # amixer set 'Left Capture Inverting Mux' IN2L
-Simple mixer control 'Capture Input',0
+ Simple mixer control 'Left Capture Inverting Mux',0
-  Capabilities: enum
+   Capabilities: enum
-  Items: 'ADC' 'DMIC'
+   Items: 'IN1L' 'IN2L' 'IN3L'
-  Item0: 'ADC'
+   Item0: 'IN2L'
-root@imx8m-var-dart:~# amixer set 'DMIC Mux' DMIC2
+ # amixer set 'Right Capture Inverting Mux' IN2R
-Simple mixer control 'DMIC Mux',0
+ Simple mixer control 'Right Capture Inverting Mux',0
-  Capabilities: enum
+   Capabilities: enum
-  Items: 'DMIC1' 'DMIC2'
+   Items: 'IN1R' 'IN2R' 'IN3R'
-  Item0: 'DMIC2'
+   Item0: 'IN2R'
-root@imx6ul-var-dart:~# arecord -f cd -d 10 test.wav
+ # amixer set 'Capture Input' ADC
-Recording WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo
+ Simple mixer control 'Capture Input',0
-root@imx6ul-var-dart:~# aplay test.wav
+   Capabilities: enum
-Playing WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo
+   Items: 'ADC' 'DMIC'
-</pre>
+   Item0: 'ADC'
+ # amixer set 'DMIC Mux' DMIC2
+ Simple mixer control 'DMIC Mux',0
+   Capabilities: enum
+   Items: 'DMIC1' 'DMIC2'
+   Item0: 'DMIC2'
+ # arecord {{#var:ARECORD_EXTRA_ARGS}} -f cd -d 10 test.wav
+ Recording WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo
+ # aplay test.wav
+ Playing WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo
 = Audio Record and Play, DMIC =
@@ Line 107: / Line 138: @@
 </pre>
 Record CD quality audio for 10 seconds into file test.wav
-<pre>
+ # arecord {{#var:ARECORD_EXTRA_ARGS}} -f cd -d 10 test.wav
-# arecord -f cd -d 10 test.wav
-</pre>
 Play the recorded file
 <pre>
@@ Line 115: / Line 144: @@
 </pre>
 Example:
-<pre>
-root@imx8m-var-dart:~# amixer set set Headphone 35
+ # amixer set Headphone 35
-Simple mixer control 'Headphone',0
+ Simple mixer control 'Headphone',0
-  Capabilities: volume pswitch
+   Capabilities: volume pswitch
-  Playback channels: Front Left - Front Right
+   Playback channels: Front Left - Front Right
-  Capture channels: Front Left - Front Right
+   Capture channels: Front Left - Front Right
-  Limits: 0 - 63
+   Limits: 0 - 63
-  Front Left: 35 [56%] [-22.00dB] Playback [on]
+   Front Left: 35 [56%] [-22.00dB] Playback [on]
-  Front Right: 35 [56%] [-22.00dB] Playback [on]
+   Front Right: 35 [56%] [-22.00dB] Playback [on]
-root@imx8m-var-dart:~# amixer set 'Capture Input' DMIC
+ # amixer set 'Capture Input' DMIC
-Simple mixer control 'Capture Input',0
+ Simple mixer control 'Capture Input',0
-  Capabilities: enum
+   Capabilities: enum
-  Items: 'ADC' 'DMIC'
+   Items: 'ADC' 'DMIC'
-  Item0: 'DMIC'
+   Item0: 'DMIC'
-root@imx8m-var-dart:~# amixer set 'DMIC Mux' DMIC1
+ # amixer set 'DMIC Mux' DMIC1
-Simple mixer control 'DMIC Mux',0
+ Simple mixer control 'DMIC Mux',0
-  Capabilities: enum
+   Capabilities: enum
-  Items: 'DMIC1' 'DMIC2'
+   Items: 'DMIC1' 'DMIC2'
-  Item0: 'DMIC1'
+   Item0: 'DMIC1'
-root@imx6ul-var-dart:~# arecord -f cd -d 10 test.wav
+ # arecord {{#var:ARECORD_EXTRA_ARGS}} -f cd -d 10 test.wav
-Recording WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo
+ Recording WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo
-root@imx6ul-var-dart:~# aplay test.wav
+ # aplay test.wav
-Playing WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo
+ Playing WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo
-</pre>
 = Advanced Controls =
@@ Line 144: / Line 172: @@
 For example:
 <pre>
-root@imx8m-var-dart:~# amixer
+# amixer
 Simple mixer control 'Headphone',0
    Capabilities: volume pswitch
@@ Line 165: / Line 193: @@
    Front Left: 57 [90%] [0.00dB] Playback [on]
    Front Right: 57 [90%] [0.00dB] Playback [on]
 Simple mixer control 'Line Output ZC',0
    Capabilities: pswitch
    Playback channels: Front Left - Front Right
    Mono:
    Front Left: Playback [on]
    Front Right: Playback [on]
 Simple mixer control 'Capture',0
    Capabilities: cvolume cswitch
    Capture channels: Front Left - Front Right
    Limits: Capture 0 - 31
    Front Left: Capture 24 [77%] [on]
    Front Right: Capture 24 [77%] [on]
 Simple mixer control 'Capture Input',0
    Capabilities: enum
    Items: 'ADC' 'DMIC'
    Item0: 'DMIC'
 ...
 </pre>
 Options:
@@ Line 191: / Line 219: @@
 For example:
 <pre>
-root@imx8m-var-dart:~# amixer sget 'Capture'
+# amixer sget 'Capture'
 Simple mixer control 'Capture',0
    Capabilities: cvolume cswitch
@@ Line 198: / Line 226: @@
    Front Left: Capture 24 [77%] [on]
    Front Right: Capture 24 [77%] [on]
-  root@imx8m-var-dart:~# amixer sset 'Capture' 25
+# amixer sset 'Capture' 25
 Simple mixer control 'Capture',0
    Capabilities: cvolume cswitch
@@ Line 208: / Line 236: @@
 Capture  currently now set to 81%.
-= Save / restore system's audio settings =
+{{#ifeq: {{#var:SUPPORT_WM8904_DRC}} | yes |
-alsactl store stores all alsamixer settings into a file<br>
+== Enabling the Dynamic Rate Controller (DRC) ==
-alsctl
+The codec WM8904 provide a Dynamic Rate Controller that can be used to amplify the DMIC input using an Automatic Gain Control (AGC) configuration.
+The details of how the DRC works are available in the application note [https://statics.cirrus.com/pubs/appNote/WAN0215.pdf WAN0215].
+In latest kernels 5.4.x, dedicated patches have been introduced to provide the available parameters shown in the applications section of WAN0215.
+To enable DRC, run:
+  amixer set 'DRC' on
+To select the DRM mode, run:
+  amixer set 'DRC Mode' 'tradition'
+The available 'DRC modes' are:
+* "default": the default settings upon reset
+* "peaklimiter": the signal level is unchanged for amplitudes below the knee, but sharply reduced for amplitudes above the knee. Normally the knee will be at a high amplitude e.g. around -6dB, so that the majority of the dynamic range is unchanged
+* "tradition": typical traditional ALC characteristic
+* "soft": used in applications where a gentler ALC characteristic is required, for example where both speech and music recording is required without reconfiguring compressor parameters
+* "music": uses even gentler compression characteristics and uses a higher knee threshold to limit the gain to around 20dB
+Additional modes may be added, providing the relevant registers configurations in arch/arm64/boot/dts/freescale/{{#var:DEFAULT_DTB}} under kernel source tree:
+<pre>
+	wm8904: codec@1a {
+		...
+		num-drc-cfgs = <5>; /* must match the number of items in the following 2 lists */
+		drc-cfg-names = "default", "peaklimiter", "tradition", "soft", "music";
+		drc-cfg-regs =
+				/* coded default: KNEE_IP = KNEE_OP = 0, HI_COMP = LO_COMP = 1  */
+				<0x01af 0x3248 0x0000 0x0000>,
+				/* coded default: KNEE_IP = -24, KNEE_OP = -6, HI_COMP = 1/4, LO_COMP = 1 */
+				<0x04af 0x324b 0x0010 0x0408>,
+				/* coded default: KNEE_IP = -42, KNEE_OP = -3, HI_COMP = 0, LO_COMP = 1 */
+				<0x04af 0x324b 0x0028 0x0704>,
+				/* coded default: KNEE_IP = -45, KNEE_OP = -9, HI_COMP = 1/8, LO_COMP = 1 */
+				<0x04af 0x324b 0x0018 0x078c>,
+				/* coded default: KNEE_IP = -30, KNEE_OP = -10.5, HI_COMP = 1/4, LO_COMP = 1 */
+				<0x04af 0x324b 0x0010 0x050e>;
+		...
+	};
+</pre>
+| }}
+= Save/restore system's audio settings =
+alsactl store stores all alsamixer settings into a file.<br>
 Options:
 <pre>