我尝试同时使用 HiFi Berry DAC 和 Raspberry PI 3B 的板载音频。我已经尝试使用 pcm 路由和 2 个 pcm dmix 配置 alsa 以获得所需的结果。扬声器测试证明我的两个 dmix 设备工作正常，但是当我尝试使用路由设备时，它只是出错并出现以下错误：
# speaker-test -D plug:dualout
speaker-test 1.1.8
Playback device is plug:dualout
Stream parameters are 48000Hz, S16_LE, 1 channels
Using 16 octaves of pink noise
ALSA lib pcm.c:2434:(snd_pcm_open_conf) type is not defined
Playback open error: -2,No such file or directory
这是我当前的 asound.conf
# cat /etc/asound.conf
pcm.headphones {
type hw
card 0
}
ctl.headphones {
type hw
card 0
}
pcm.lineout {
type hw
card 1
}
ctl.lineout {
type hw
card 1
}
pcm.headphonesDmix {
type dmix
ipc_key 1024
slave {
pcm "headphones"
channels 2
}
bindings {
0 0
1 1
}
}
pcm.lineoutDmix {
type dmix
ipc_key 2048
slave {
pcm "lineout"
channels 2
}
bindings {
0 0
1 1
}
}
pcm.dualout {
type route
slave.pcm {
slaves.a.pcm "headphonesDmix"
slaves.b.pcm "lineoutDmix"
slaves.a.channels 2
slaves.b.channels 2
bindings.0.slave a
bindings.0.channel 0
bindings.1.slave a
bindings.1.channel 1
bindings.0.slave b
bindings.0.channel 0
bindings.1.slave b
bindings.1.channel 1
}
ttable.0.0 1
ttable.1.1 1
}
pcm.!default {
type plug
slave {
pcm "dualout"
}
}
ctl.!default {
type hw
card 1
}
和 alsa-info 的输出
# alsa-info
ALSA Information Script v 0.4.65
--------------------------------
This script visits the following commands/files to collect diagnostic
information about your ALSA installation and sound related hardware.
dmesg
lspci
aplay
amixer
alsactl
rpm, dpkg
/proc/asound/
/sys/class/sound/
~/.asoundrc (etc.)
See '/usr/sbin/alsa-info --help' for command line options.
pcilib: Cannot open /proc/bus/pci
lspci: Cannot find any working access method.
pcilib: Cannot open /proc/bus/pci
lspci: Cannot find any working access method.
pcilib: Cannot open /proc/bus/pci
lspci: Cannot find any working access method.
cat: /tmp/alsa-info.Qjk8uwmTxC/acpidevicestatus.tmp: No such file or directory
cat: '/sys/module/snd_soc_hifiberry_dacplus/parameters/*': No such file or directory
Automatically upload ALSA information to www.alsa-project.org? [y/N] : n
Your ALSA information is in /tmp/alsa-info.txt.YVpm767lnw
# cat /tmp/alsa-info.txt.YVpm767lnw
upload=true&script=true&cardinfo=
!!################################
!!ALSA Information Script v 0.4.65
!!################################
!!Script ran on: Fri Jan 22 19:08:17 UTC 2021
!!Linux Distribution
!!------------------
ID_LIKE=debian
!!DMI Information
!!---------------
Manufacturer:
Product Name:
Product Version:
Firmware Version:
System SKU:
Board Vendor:
Board Name:
!!ACPI Device Status Information
!!---------------
!!Kernel Information
!!------------------
Kernel release: 5.4.83-v7+
Operating System: GNU/Linux
Architecture: armv7l
Processor: unknown
SMP Enabled: Yes
!!ALSA Version
!!------------
Driver version: k5.4.83-v7+
Library version: 1.1.8
Utilities version: 1.1.8
!!Loaded ALSA modules
!!-------------------
snd_bcm2835
snd_soc_hifiberry_dacplus
!!Sound Servers on this system
!!----------------------------
No sound servers found.
!!Soundcards recognised by ALSA
!!-----------------------------
0 [Headphones ]: bcm2835_headphonbcm2835 Headphones - bcm2835 Headphones
bcm2835 Headphones
1 [sndrpihifiberry]: HifiberryDacp - snd_rpi_hifiberry_dacplus
snd_rpi_hifiberry_dacplus
!!PCI Soundcards installed in the system
!!--------------------------------------
!!Modprobe options (Sound related)
!!--------------------------------
snd_pcsp: index=-2
snd_usb_audio: index=-2
snd_atiixp_modem: index=-2
snd_intel8x0m: index=-2
snd_via82xx_modem: index=-2
snd_bcm2835: enable_compat_alsa=0
snd_bcm2835: enable_hdmi=1
!!Loaded sound module options
!!---------------------------
!!Module: snd_bcm2835
enable_compat_alsa : N
enable_hdmi : Y
enable_headphones : Y
force_bulk : N
!!Module: snd_soc_hifiberry_dacplus
* :
!!ALSA Device nodes
!!-----------------
crw-rw----+ 1 root audio 116, 0 Jan 22 19:19 /dev/snd/controlC0
crw-rw----+ 1 root audio 116, 32 Jan 22 19:19 /dev/snd/controlC1
crw-rw----+ 1 root audio 116, 16 Jan 22 19:19 /dev/snd/pcmC0D0p
crw-rw----+ 1 root audio 116, 48 Jan 22 19:19 /dev/snd/pcmC1D0p
crw-rw----+ 1 root audio 116, 1 Jan 22 19:19 /dev/snd/seq
crw-rw----+ 1 root audio 116, 33 Jan 22 19:19 /dev/snd/timer
/dev/snd/by-path:
total 0
drwxr-xr-x 2 root root 80 Jan 22 19:19 .
drwxr-xr-x 3 root root 180 Jan 22 19:19 ..
lrwxrwxrwx 1 root root 12 Jan 22 19:19 platform-bcm2835_audio -> ../controlC0
lrwxrwxrwx 1 root root 12 Jan 22 19:19 platform-soc:sound -> ../controlC1
!!ALSA configuration files
!!------------------------
!!System wide config file (/etc/asound.conf)
pcm.headphones {
type hw
card 0
}
ctl.headphones {
type hw
card 0
}
pcm.lineout {
type hw
card 1
}
ctl.lineout {
type hw
card 1
}
pcm.headphonesDmix {
type dmix
ipc_key 1024
slave {
pcm "headphones"
channels 2
}
bindings {
0 0
1 1
}
}
pcm.lineoutDmix {
type dmix
ipc_key 2048
slave {
pcm "lineout"
channels 2
}
bindings {
0 0
1 1
}
}
pcm.dualout {
type route
slave.pcm {
slaves.a.pcm "headphonesDmix"
slaves.b.pcm "lineoutDmix"
slaves.a.channels 2
slaves.b.channels 2
bindings.0.slave a
bindings.0.channel 0
bindings.1.slave a
bindings.1.channel 1
bindings.0.slave b
bindings.0.channel 0
bindings.1.slave b
bindings.1.channel 1
}
ttable.0.0 1
ttable.1.1 1
}
pcm.!default {
type plug
slave {
pcm "dualout"
}
}
ctl.!default {
type hw
card 1
}
!!Aplay/Arecord output
!!--------------------
APLAY
**** List of PLAYBACK Hardware Devices ****
card 0: Headphones [bcm2835 Headphones], device 0: bcm2835 Headphones [bcm2835 Headphones]
Subdevices: 8/8
Subdevice #0: subdevice #0
Subdevice #1: subdevice #1
Subdevice #2: subdevice #2
Subdevice #3: subdevice #3
Subdevice #4: subdevice #4
Subdevice #5: subdevice #5
Subdevice #6: subdevice #6
Subdevice #7: subdevice #7
card 1: sndrpihifiberry [snd_rpi_hifiberry_dacplus], device 0: HiFiBerry DAC+ Pro HiFi pcm512x-hifi-0 [HiFiBerry DAC+ Pro HiFi pcm512x-hifi-0]
Subdevices: 1/1
Subdevice #0: subdevice #0
ARECORD
**** List of CAPTURE Hardware Devices ****
!!Amixer output
!!-------------
!!-------Mixer controls for card Headphones
Card hw:0 'Headphones'/'bcm2835 Headphones'
Mixer name : 'Broadcom Mixer'
Components : ''
Controls : 2
Simple ctrls : 1
Simple mixer control 'Headphone',0
Capabilities: pvolume pvolume-joined pswitch pswitch-joined
Playback channels: Mono
Limits: Playback -10239 - 400
Mono: Playback 400 [100%] [4.00dB] [on]
!!-------Mixer controls for card sndrpihifiberry
Card hw:1 'sndrpihifiberry'/'snd_rpi_hifiberry_dacplus'
Mixer name : ''
Components : ''
Controls : 20
Simple ctrls : 19
Simple mixer control 'DSP Program',0
Capabilities: enum
Items: 'FIR interpolation with de-emphasis' 'Low latency IIR with de-emphasis' 'High attenuation with de-emphasis' 'Fixed process flow' 'Ringing-less low latency FIR'
Item0: 'FIR interpolation with de-emphasis'
Simple mixer control 'Analogue',0
Capabilities: pvolume
Playback channels: Front Left - Front Right
Limits: Playback 0 - 1
Mono:
Front Left: Playback 1 [100%] [0.00dB]
Front Right: Playback 1 [100%] [0.00dB]
Simple mixer control 'Analogue Playback Boost',0
Capabilities: volume
Playback channels: Front Left - Front Right
Capture channels: Front Left - Front Right
Limits: 0 - 1
Front Left: 1 [100%] [0.80dB]
Front Right: 1 [100%] [0.80dB]
Simple mixer control 'Auto Mute',0
Capabilities: pswitch
Playback channels: Front Left - Front Right
Mono:
Front Left: Playback [on]
Front Right: Playback [on]
Simple mixer control 'Auto Mute Mono',0
Capabilities: pswitch pswitch-joined
Playback channels: Mono
Mono: Playback [on]
Simple mixer control 'Auto Mute Time Left',0
Capabilities: enum
Items: '21ms' '106ms' '213ms' '533ms' '1.07s' '2.13s' '5.33s' '10.66s'
Item0: '21ms'
Simple mixer control 'Auto Mute Time Right',0
Capabilities: enum
Items: '21ms' '106ms' '213ms' '533ms' '1.07s' '2.13s' '5.33s' '10.66s'
Item0: '21ms'
Simple mixer control 'Clock Missing Period',0
Capabilities: enum
Items: '1s' '2s' '3s' '4s' '5s' '6s' '7s' '8s'
Item0: '1s'
Simple mixer control 'Deemphasis',0
Capabilities: pswitch pswitch-joined
Playback channels: Mono
Mono: Playback [on]
Simple mixer control 'Digital',0
Capabilities: pvolume pswitch
Playback channels: Front Left - Front Right
Limits: Playback 0 - 207
Mono:
Front Left: Playback 207 [100%] [0.00dB] [on]
Front Right: Playback 207 [100%] [0.00dB] [on]
Simple mixer control 'Max Overclock DAC',0
Capabilities: volume volume-joined
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 40
Mono: 0 [0%]
Simple mixer control 'Max Overclock DSP',0
Capabilities: volume volume-joined
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 40
Mono: 0 [0%]
Simple mixer control 'Max Overclock PLL',0
Capabilities: volume volume-joined
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 20
Mono: 0 [0%]
Simple mixer control 'Volume Ramp Down Emergency Rate',0
Capabilities: enum
Items: '1 sample/update' '2 samples/update' '4 samples/update' 'Immediate'
Item0: '1 sample/update'
Simple mixer control 'Volume Ramp Down Emergency Step',0
Capabilities: enum
Items: '4dB/step' '2dB/step' '1dB/step' '0.5dB/step'
Item0: '4dB/step'
Simple mixer control 'Volume Ramp Down Rate',0
Capabilities: enum
Items: '1 sample/update' '2 samples/update' '4 samples/update' 'Immediate'
Item0: '1 sample/update'
Simple mixer control 'Volume Ramp Down Step',0
Capabilities: enum
Items: '4dB/step' '2dB/step' '1dB/step' '0.5dB/step'
Item0: '1dB/step'
Simple mixer control 'Volume Ramp Up Rate',0
Capabilities: enum
Items: '1 sample/update' '2 samples/update' '4 samples/update' 'Immediate'
Item0: '1 sample/update'
Simple mixer control 'Volume Ramp Up Step',0
Capabilities: enum
Items: '4dB/step' '2dB/step' '1dB/step' '0.5dB/step'
Item0: '1dB/step'
!!Alsactl output
!!--------------
--startcollapse--
state.Headphones {
control.1 {
iface MIXER
name 'Headphone Playback Volume'
value 400
comment {
access 'read write'
type INTEGER
count 1
range '-10239 - 400'
dbmin -9999999
dbmax 400
dbvalue.0 400
}
}
control.2 {
iface MIXER
name 'Headphone Playback Switch'
value true
comment {
access 'read write'
type BOOLEAN
count 1
}
}
}
state.sndrpihifiberry {
control.1 {
iface MIXER
name 'Digital Playback Volume'
value.0 207
value.1 207
comment {
access 'read write'
type INTEGER
count 2
range '0 - 207'
dbmin -9999999
dbmax 0
dbvalue.0 0
dbvalue.1 0
}
}
control.2 {
iface MIXER
name 'Analogue Playback Volume'
value.0 1
value.1 1
comment {
access 'read write'
type INTEGER
count 2
range '0 - 1'
dbmin -600
dbmax 0
dbvalue.0 0
dbvalue.1 0
}
}
control.3 {
iface MIXER
name 'Analogue Playback Boost Volume'
value.0 1
value.1 1
comment {
access 'read write'
type INTEGER
count 2
range '0 - 1'
dbmin 0
dbmax 80
dbvalue.0 80
dbvalue.1 80
}
}
control.4 {
iface MIXER
name 'Digital Playback Switch'
value.0 true
value.1 true
comment {
access 'read write'
type BOOLEAN
count 2
}
}
control.5 {
iface MIXER
name 'Deemphasis Switch'
value true
comment {
access 'read write'
type BOOLEAN
count 1
}
}
control.6 {
iface MIXER
name 'DSP Program'
value 'FIR interpolation with de-emphasis'
comment {
access 'read write'
type ENUMERATED
count 1
item.0 'FIR interpolation with de-emphasis'
item.1 'Low latency IIR with de-emphasis'
item.2 'High attenuation with de-emphasis'
item.3 'Fixed process flow'
item.4 'Ringing-less low latency FIR'
}
}
control.7 {
iface MIXER
name 'Clock Missing Period'
value '1s'
comment {
access 'read write'
type ENUMERATED
count 1
item.0 '1s'
item.1 '2s'
item.2 '3s'
item.3 '4s'
item.4 '5s'
item.5 '6s'
item.6 '7s'
item.7 '8s'
}
}
control.8 {
iface MIXER
name 'Auto Mute Time Left'
value '21ms'
comment {
access 'read write'
type ENUMERATED
count 1
item.0 '21ms'
item.1 '106ms'
item.2 '213ms'
item.3 '533ms'
item.4 '1.07s'
item.5 '2.13s'
item.6 '5.33s'
item.7 '10.66s'
}
}
control.9 {
iface MIXER
name 'Auto Mute Time Right'
value '21ms'
comment {
access 'read write'
type ENUMERATED
count 1
item.0 '21ms'
item.1 '106ms'
item.2 '213ms'
item.3 '533ms'
item.4 '1.07s'
item.5 '2.13s'
item.6 '5.33s'
item.7 '10.66s'
}
}
control.10 {
iface MIXER
name 'Auto Mute Mono Switch'
value true
comment {
access 'read write'
type BOOLEAN
count 1
}
}
control.11 {
iface MIXER
name 'Auto Mute Switch'
value.0 true
value.1 true
comment {
access 'read write'
type BOOLEAN
count 2
}
}
control.12 {
iface MIXER
name 'Volume Ramp Down Rate'
value '1 sample/update'
comment {
access 'read write'
type ENUMERATED
count 1
item.0 '1 sample/update'
item.1 '2 samples/update'
item.2 '4 samples/update'
item.3 Immediate
}
}
control.13 {
iface MIXER
name 'Volume Ramp Down Step'
value '1dB/step'
comment {
access 'read write'
type ENUMERATED
count 1
item.0 '4dB/step'
item.1 '2dB/step'
item.2 '1dB/step'
item.3 '0.5dB/step'
}
}
control.14 {
iface MIXER
name 'Volume Ramp Up Rate'
value '1 sample/update'
comment {
access 'read write'
type ENUMERATED
count 1
item.0 '1 sample/update'
item.1 '2 samples/update'
item.2 '4 samples/update'
item.3 Immediate
}
}
control.15 {
iface MIXER
name 'Volume Ramp Up Step'
value '1dB/step'
comment {
access 'read write'
type ENUMERATED
count 1
item.0 '4dB/step'
item.1 '2dB/step'
item.2 '1dB/step'
item.3 '0.5dB/step'
}
}
control.16 {
iface MIXER
name 'Volume Ramp Down Emergency Rate'
value '1 sample/update'
comment {
access 'read write'
type ENUMERATED
count 1
item.0 '1 sample/update'
item.1 '2 samples/update'
item.2 '4 samples/update'
item.3 Immediate
}
}
control.17 {
iface MIXER
name 'Volume Ramp Down Emergency Step'
value '4dB/step'
comment {
access 'read write'
type ENUMERATED
count 1
item.0 '4dB/step'
item.1 '2dB/step'
item.2 '1dB/step'
item.3 '0.5dB/step'
}
}
control.18 {
iface MIXER
name 'Max Overclock PLL'
value 0
comment {
access 'read write'
type INTEGER
count 1
range '0 - 20'
}
}
control.19 {
iface MIXER
name 'Max Overclock DSP'
value 0
comment {
access 'read write'
type INTEGER
count 1
range '0 - 40'
}
}
control.20 {
iface MIXER
name 'Max Overclock DAC'
value 0
comment {
access 'read write'
type INTEGER
count 1
range '0 - 40'
}
}
}
--endcollapse--
!!All Loaded Modules
!!------------------
8021q
backlight
bcm2835_codec
bcm2835_isp
bcm2835_mmal_vchiq
bcm2835_v4l2
bluetooth
bnep
brcmfmac
brcmutil
btbcm
cfg80211
clk_hifiberry_dacpro
cmac
ecc
ecdh_generic
fixed
garp
hci_uart
i2c_bcm2835
input_polldev
ip_tables
ipv6
joydev
libsha256
llc
mc
raspberrypi_hwmon
raspberrypi_ts
regmap_i2c
rfkill
rpi_backlight
sha256_generic
snd
snd_bcm2835
snd_compress
snd_pcm
snd_pcm_dmaengine
snd_soc_bcm2835_i2s
snd_soc_core
snd_soc_hifiberry_dacplus
snd_soc_pcm512x
snd_soc_pcm512x_i2c
snd_timer
stp
uio
uio_pdrv_genirq
v4l2_mem2mem
vc_sm_cma
videobuf2_common
videobuf2_dma_contig
videobuf2_memops
videobuf2_v4l2
videobuf2_vmalloc
videodev
x_tables
!!ALSA/HDA dmesg
!!--------------
[ 0.000000] Built 1 zonelists, mobility grouping on. Total pages: 240555
[ 0.000000] Kernel command line: coherent_pool=1M 8250.nr_uarts=0 snd_bcm2835.enable_compat_alsa=0 snd_bcm2835.enable_hdmi=1 bcm2708_fb.fbwidth=800 bcm2708_fb.fbheight=480 bcm2708_fb.fbswap=1 vc_mem.mem_base=0x3ec00000 vc_mem.mem_size=0x40000000 console=ttyS0,115200 console=tty1 root=PARTUUID=6c586e13-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait quiet splash plymouth.ignore-serial-consoles logo.nologo vt.global_cursor_default=0
[ 0.000000] Dentry cache hash table entries: 131072 (order: 7, 524288 bytes, linear)
--
[ 6.359946] videodev: Linux video capture interface: v2.00
[ 6.394714] snd_bcm2835: module is from the staging directory, the quality is unknown, you have been warned.
[ 6.442322] bcm2835_mmal_vchiq: module is from the staging directory, the quality is unknown, you have been warned.
--
[ 6.518353] bcm2835-codec bcm2835-codec: Loaded V4L2 isp
[ 6.708013] snd-rpi-hifiberry-dacplus soc:sound: ASoC: failed to init link HiFiBerry DAC+: -517
[ 6.742868] snd-rpi-hifiberry-dacplus soc:sound: ASoC: failed to init link HiFiBerry DAC+: -517
[ 6.808548] input: raspberrypi-ts as /devices/platform/soc/soc:firmware/soc:firmware:touchscreen/input/input0
[ 6.810037] snd-rpi-hifiberry-dacplus soc:sound: ASoC: failed to init link HiFiBerry DAC+: -517
[ 7.117404] cfg80211: Loading compiled-in X.509 certificates for regulatory database
[ 7.294399] cfg80211: Loaded X.509 cert 'sforshee: 00b28ddf47aef9cea7'
[ 7.414779] snd-rpi-hifiberry-dacplus soc:sound: ASoC: failed to init link HiFiBerry DAC+: -517
[ 7.415491] brcmfmac: F1 signature read @0x18000000=0x1541a9a6
--
[ 7.421810] usbcore: registered new interface driver brcmfmac
[ 7.426330] snd-rpi-hifiberry-dacplus soc:sound: ASoC: failed to init link HiFiBerry DAC+: -517
[ 7.452141] brcmfmac mmc1:0001:1: Direct firmware load for brcm/brcmfmac43430-sdio.raspberrypi,3-model-b.txt failed with error -2
--
[ 7.671399] brcmfmac: brcmf_c_preinit_dcmds: Firmware: BCM43430/1 wl0: Oct 22 2019 01:59:28 version 7.45.98.94 (r723000 CY) FWID 01-3b33decd
[ 8.633347] snd-rpi-hifiberry-dacplus soc:sound: pcm512x-hifi <-> 3f203000.i2s mapping ok
!!Packages installed
!!--------------------
ii alsa-utils 1.1.8-2 armhf Utilities for configuring and using ALSA
卡0是板载“耳机”-Out
卡 1 是 HiFi Berry 卡