我们开发了一个基于linux的嵌入式板，并从评估板设计中复制了处理器和音频芯片，当然也使用了alsa。在评估板上，音频播放和录音工作正常。在我们的主板上，只有播放功能有效。 “arecord”正在工作，但实际上没有收到声音。我们没有对驱动程序源代码进行任何修改。设备树的配置与评估板中相同。
我发现音频控制器中所需的启用位均未设置，因此 alsa 在录制时似乎没有配置设备。当我手动设置位时，录音确实可以工作，尽管采样频率错误。
我已经多次检查 alsamixer 设置，所有值似乎都很合理。所以这可能只是其他地方的一个小设置让 alsa 表现出这种行为，我不知道。
在 alsamixer 设置中，我缺少输入静音开关。它在源代码中定义，但没有出现在 alsamixer 中。为了检查混音器中的输入是否静音，我执行了“alsactl store”并查看了生成的文件。它没有静音。
你有什么想法我还可以尝试什么吗？或者源代码中的哪个位置应该启用控制器？
处理器是Atmel SAMA5D4，音频芯片是WM8904。 Linux 版本 5.15.32 音频驱动程序：
声音/soc/atmel/atmel_wm8904.c 声音/soc/codecs/wm8904.c
混合器：
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: 45 [71%] [-12.00dB] Playback [on]
Front Right: 45 [71%] [-12.00dB] 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 5 [16%] [on]
Front Right: Capture 5 [16%] [on]
Simple mixer control 'ADC 128x OSR',0
Capabilities: pswitch pswitch-joined
Playback channels: Mono
Mono: Playback [on]
Simple mixer control 'AIFOUTL Mux',0
Capabilities: enum
Items: 'Left' 'Right'
Item0: 'Left'
Simple mixer control 'AIFOUTR Mux',0
Capabilities: enum
Items: 'Left' 'Right'
Item0: 'Right'
Simple mixer control 'DAC Deemphasis',0
Capabilities: pswitch pswitch-joined
Playback channels: Mono
Mono: Playback [off]
Simple mixer control 'DAC OSRx2',0
Capabilities: pswitch pswitch-joined
Playback channels: Mono
Mono: Playback [off]
Simple mixer control 'DACL Mux',0
Capabilities: enum
Items: 'Left' 'Right'
Item0: 'Left'
Simple mixer control 'DACR Mux',0
Capabilities: enum
Items: 'Left' 'Right'
Item0: 'Right'
Simple mixer control 'DRC',0
Capabilities: pswitch pswitch-joined
Playback channels: Mono
Mono: Playback [off]
Simple mixer control 'DRC Path',0
Capabilities: enum
Items: 'ADC' 'DAC'
Item0: 'ADC'
Simple mixer control 'Digital',0
Capabilities: pvolume cvolume
Playback channels: Front Left - Front Right
Capture channels: Front Left - Front Right
Limits: Playback 0 - 96 Capture 0 - 119
Front Left: Playback 96 [100%] [0.00dB] Capture 96 [81%] [0.00dB]
Front Right: Playback 96 [100%] [0.00dB] Capture 96 [81%] [0.00dB]
Simple mixer control 'Digital Playback Boost',0
Capabilities: volume volume-joined
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 3
Mono: 0 [0%] [0.00dB]
Simple mixer control 'Digital Sidetone',0
Capabilities: volume
Playback channels: Front Left - Front Right
Capture channels: Front Left - Front Right
Limits: 0 - 15
Front Left: 0 [0%] [-36.00dB]
Front Right: 0 [0%] [-36.00dB]
Simple mixer control 'EQ',0
Capabilities: pswitch pswitch-joined
Playback channels: Mono
Mono: Playback [off]
Simple mixer control 'EQ1',0
Capabilities: volume volume-joined
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 24
Mono: 12 [50%] [0.00dB]
Simple mixer control 'EQ2',0
Capabilities: volume volume-joined
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 24
Mono: 12 [50%] [0.00dB]
Simple mixer control 'EQ3',0
Capabilities: volume volume-joined
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 24
Mono: 12 [50%] [0.00dB]
Simple mixer control 'EQ4',0
Capabilities: volume volume-joined
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 24
Mono: 12 [50%] [0.00dB]
Simple mixer control 'EQ5',0
Capabilities: volume volume-joined
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 24
Mono: 12 [50%] [0.00dB]
Simple mixer control 'HPL Mux',0
Capabilities: enum
Items: 'DAC' 'Bypass'
Item0: 'DAC'
Simple mixer control 'HPR Mux',0
Capabilities: enum
Items: 'DAC' 'Bypass'
Item0: 'DAC'
Simple mixer control 'High Pass Filter',0
Capabilities: pswitch pswitch-joined
Playback channels: Mono
Mono: Playback [on]
Simple mixer control 'High Pass Filter Mode',0
Capabilities: enum
Items: 'Hi-fi' 'Voice 1' 'Voice 2' 'Voice 3'
Item0: 'Hi-fi'
Simple mixer control 'LINEL Mux',0
Capabilities: enum
Items: 'DAC' 'Bypass'
Item0: 'DAC'
Simple mixer control 'LINER Mux',0
Capabilities: enum
Items: 'DAC' 'Bypass'
Item0: 'DAC'
Simple mixer control 'Left Capture Inverting Mux',0
Capabilities: enum
Items: 'IN1L' 'IN2L' 'IN3L'
Item0: 'IN1L'
Simple mixer control 'Left Capture Mode',0
Capabilities: enum
Items: 'Single-Ended' 'Differential Line' 'Differential Mic'
Item0: 'Single-Ended'
Simple mixer control 'Left Capture Mux',0
Capabilities: enum
Items: 'IN1L' 'IN2L' 'IN3L'
Item0: 'IN2L'
Simple mixer control 'Left Sidetone',0
Capabilities: enum
Items: 'None' 'Left' 'Right'
Item0: 'None'
Simple mixer control 'Right Capture Inverting Mux',0
Capabilities: enum
Items: 'IN1R' 'IN2R' 'IN3R'
Item0: 'IN1R'
Simple mixer control 'Right Capture Mode',0
Capabilities: enum
Items: 'Single-Ended' 'Differential Line' 'Differential Mic'
Item0: 'Single-Ended'
Simple mixer control 'Right Capture Mux',0
Capabilities: enum
Items: 'IN1R' 'IN2R' 'IN3R'
Item0: 'IN2R'
Simple mixer control 'Right Sidetone',0
Capabilities: enum
Items: 'None' 'Left' 'Right'
Item0: 'None'
/var/lib/alsa/asound.state：
state.SAMA5D4GGARD {
control.1 {
iface MIXER
name 'EQ1 Volume'
value 12
comment {
access 'read write'
type INTEGER
count 1
range '0 - 24'
dbmin -1200
dbmax 1200
dbvalue.0 0
}
}
control.2 {
iface MIXER
name 'EQ2 Volume'
value 12
comment {
access 'read write'
type INTEGER
count 1
range '0 - 24'
dbmin -1200
dbmax 1200
dbvalue.0 0
}
}
control.3 {
iface MIXER
name 'EQ3 Volume'
value 12
comment {
access 'read write'
type INTEGER
count 1
range '0 - 24'
dbmin -1200
dbmax 1200
dbvalue.0 0
}
}
control.4 {
iface MIXER
name 'EQ4 Volume'
value 12
comment {
access 'read write'
type INTEGER
count 1
range '0 - 24'
dbmin -1200
dbmax 1200
dbvalue.0 0
}
}
control.5 {
iface MIXER
name 'EQ5 Volume'
value 12
comment {
access 'read write'
type INTEGER
count 1
range '0 - 24'
dbmin -1200
dbmax 1200
dbvalue.0 0
}
}
control.6 {
iface MIXER
name 'Digital Capture Volume'
value.0 96
value.1 96
comment {
access 'read write'
type INTEGER
count 2
range '0 - 119'
dbmin -9999999
dbmax 1725
dbvalue.0 0
dbvalue.1 0
}
}
control.7 {
iface MIXER
name 'Capture Volume'
value.0 5
value.1 5
comment {
access 'read write'
type INTEGER
count 2
range '0 - 31'
}
}
control.8 {
iface MIXER
name 'Capture Switch'
value.0 true
value.1 true
comment {
access 'read write'
type BOOLEAN
count 2
}
}
control.9 {
iface MIXER
name 'High Pass Filter Switch'
value true
comment {
access 'read write'
type BOOLEAN
count 1
}
}
control.10 {
iface MIXER
name 'High Pass Filter Mode'
value Hi-fi
comment {
access 'read write'
type ENUMERATED
count 1
item.0 Hi-fi
item.1 'Voice 1'
item.2 'Voice 2'
item.3 'Voice 3'
}
}
control.11 {
iface MIXER
name 'ADC 128x OSR Switch'
value true
comment {
access 'read write'
type BOOLEAN
count 1
}
}
control.12 {
iface MIXER
name 'Digital Playback Boost Volume'
value 0
comment {
access 'read write'
type INTEGER
count 1
range '0 - 3'
dbmin 0
dbmax 1800
dbvalue.0 0
}
}
control.13 {
iface MIXER
name 'Digital Playback Volume'
value.0 96
value.1 96
comment {
access 'read write'
type INTEGER
count 2
range '0 - 96'
dbmin -9999999
dbmax 0
dbvalue.0 0
dbvalue.1 0
}
}
control.14 {
iface MIXER
name 'Headphone Volume'
value.0 45
value.1 45
comment {
access 'read write'
type INTEGER
count 2
range '0 - 63'
dbmin -5700
dbmax 600
dbvalue.0 -1200
dbvalue.1 -1200
}
}
control.15 {
iface MIXER
name 'Headphone Switch'
value.0 true
value.1 true
comment {
access 'read write'
type BOOLEAN
count 2
}
}
control.16 {
iface MIXER
name 'Headphone ZC Switch'
value.0 true
value.1 true
comment {
access 'read write'
type BOOLEAN
count 2
}
}
control.17 {
iface MIXER
name 'Line Output Volume'
value.0 57
value.1 57
comment {
access 'read write'
type INTEGER
count 2
range '0 - 63'
dbmin -5700
dbmax 600
dbvalue.0 0
dbvalue.1 0
}
}
control.18 {
iface MIXER
name 'Line Output Switch'
value.0 true
value.1 true
comment {
access 'read write'
type BOOLEAN
count 2
}
}
control.19 {
iface MIXER
name 'Line Output ZC Switch'
value.0 true
value.1 true
comment {
access 'read write'
type BOOLEAN
count 2
}
}
control.20 {
iface MIXER
name 'EQ Switch'
value false
comment {
access 'read write'
type BOOLEAN
count 1
}
}
control.21 {
iface MIXER
name 'DRC Switch'
value false
comment {
access 'read write'
type BOOLEAN
count 1
}
}
control.22 {
iface MIXER
name 'DRC Path'
value ADC
comment {
access 'read write'
type ENUMERATED
count 1
item.0 ADC
item.1 DAC
}
}
control.23 {
iface MIXER
name 'DAC OSRx2 Switch'
value false
comment {
access 'read write'
type BOOLEAN
count 1
}
}
control.24 {
iface MIXER
name 'DAC Deemphasis Switch'
value false
comment {
access 'read write'
type BOOLEAN
count 1
}
}
control.25 {
iface MIXER
name 'Digital Sidetone Volume'
value.0 0
value.1 0
comment {
access 'read write'
type INTEGER
count 2
range '0 - 15'
dbmin -3600
dbmax 900
dbvalue.0 -3600
dbvalue.1 -3600
}
}
control.26 {
iface MIXER
name 'Left Capture Mux'
value IN2L
comment {
access 'read write'
type ENUMERATED
count 1
item.0 IN1L
item.1 IN2L
item.2 IN3L
}
}
control.27 {
iface MIXER
name 'Left Capture Inverting Mux'
value IN1L
comment {
access 'read write'
type ENUMERATED
count 1
item.0 IN1L
item.1 IN2L
item.2 IN3L
}
}
control.28 {
iface MIXER
name 'Left Capture Mode'
value Single-Ended
comment {
access 'read write'
type ENUMERATED
count 1
item.0 Single-Ended
item.1 'Differential Line'
item.2 'Differential Mic'
}
}
control.29 {
iface MIXER
name 'Right Capture Mux'
value IN2R
comment {
access 'read write'
type ENUMERATED
count 1
item.0 IN1R
item.1 IN2R
item.2 IN3R
}
}
control.30 {
iface MIXER
name 'Right Capture Inverting Mux'
value IN1R
comment {
access 'read write'
type ENUMERATED
count 1
item.0 IN1R
item.1 IN2R
item.2 IN3R
}
}
control.31 {
iface MIXER
name 'Right Capture Mode'
value Single-Ended
comment {
access 'read write'
type ENUMERATED
count 1
item.0 Single-Ended
item.1 'Differential Line'
item.2 'Differential Mic'
}
}
control.32 {
iface MIXER
name 'AIFOUTL Mux'
value Left
comment {
access 'read write'
type ENUMERATED
count 1
item.0 Left
item.1 Right
}
}
control.33 {
iface MIXER
name 'AIFOUTR Mux'
value Right
comment {
access 'read write'
type ENUMERATED
count 1
item.0 Left
item.1 Right
}
}
control.34 {
iface MIXER
name 'DACL Mux'
value Left
comment {
access 'read write'
type ENUMERATED
count 1
item.0 Left
item.1 Right
}
}
control.35 {
iface MIXER
name 'DACR Mux'
value Right
comment {
access 'read write'
type ENUMERATED
count 1
item.0 Left
item.1 Right
}
}
control.36 {
iface MIXER
name 'Left Sidetone'
value None
comment {
access 'read write'
type ENUMERATED
count 1
item.0 None
item.1 Left
item.2 Right
}
}
control.37 {
iface MIXER
name 'Right Sidetone'
value None
comment {
access 'read write'
type ENUMERATED
count 1
item.0 None
item.1 Left
item.2 Right
}
}
control.38 {
iface MIXER
name 'HPL Mux'
value DAC
comment {
access 'read write'
type ENUMERATED
count 1
item.0 DAC
item.1 Bypass
}
}
control.39 {
iface MIXER
name 'HPR Mux'
value DAC
comment {
access 'read write'
type ENUMERATED
count 1
item.0 DAC
item.1 Bypass
}
}
control.40 {
iface MIXER
name 'LINEL Mux'
value DAC
comment {
access 'read write'
type ENUMERATED
count 1
item.0 DAC
item.1 Bypass
}
}
control.41 {
iface MIXER
name 'LINER Mux'
value DAC
comment {
access 'read write'
type ENUMERATED
count 1
item.0 DAC
item.1 Bypass
}
}
}