Audio
啟用 ALSA 以從 CS4207 的 SPDIF 輸入擷取音頻
在使用 Congatec 的SA5 模組和附加的CS4207 HDA 編解碼器的自定義平台上，我正在嘗試使用編解碼器數字 SPDIF 輸入和輸出。HDA 設計是從 Congatec 的conga-SEVAL評估板上複製而來的。
SPDIF 輸出（連接到放大器）開箱即用 - 這裡沒有問題。
但是 SPDIF 輸入（需要記錄信號）讓我有些頭疼。
在測試期間，我使用的是 Xubuntu 20.04
Linux Test-01 5.4.0-48-generic #52-Ubuntu SMP Thu Sep 10 10:58:49 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux稍後我們將在 buildroot 中實現這些功能。
到目前為止我所做的
通過使用hda_analyser.py工具，我可以看到預設情況下 SPDIF 輸入小元件是禁用的。手動啟用它們對結果沒有影響：
# Node 0x07 SPDIF Reciver Input Converter - Enable hda-verb /dev/snd/hwC0D0 0x07 0x70d 0x01 # Node 0x0f SPDIF Reciver Input Pin - Enable hda-verb /dev/snd/hwC0D0 0x0f 0x707 0x20當我向 SPDIF 輸入提供信號時，hda_analyser 顯示信號的有效標誌和控製字內容。所以我認為來源很好。
通過手動啟用 CS4207 的“SPDIF RX to TX1 loopthru”功能：
# Enable Rx to Tx1 Loopthru hda-verb /dev/snd/hwC0D0 0x11 0x0500 0x01 && hda-verb /dev/snd/hwC0D0 0x11 0x0400 0x402a我也能聽到從連接到 SPDIF 輸出的揚聲器饋入 SPDIF 輸入的信號。
-> 所以我的結論是硬體部分應該沒問題。
在 ALSA 方面，我認為存在配置問題，因為未列出 IEC958 數字擷取設備。但那是我無法理解的部分。有很多配置路徑 (
/usr/share/pulseaudio/alsa-mixer//etc/alsa/conf.d//usr/share/alsa/)，甚至更多帶有佔位符的配置模板似乎被其他東西填充。但是我沒有找到一種方法來找出有效使用的配置。在 ALSA 文件中也找不到任何提示。
的輸出
aplay -l**** List of PLAYBACK Hardware Devices **** card 0: PCH [HDA Intel PCH], device 0: CS4207 Analog [CS4207 Analog] Subdevices: 1/1 Subdevice #0: subdevice #0 card 0: PCH [HDA Intel PCH], device 1: CS4207 Digital [CS4207 Digital] Subdevices: 1/1 Subdevice #0: subdevice #0 card 0: PCH [HDA Intel PCH], device 3: HDMI 0 [HDMI 0] Subdevices: 1/1 Subdevice #0: subdevice #0 card 0: PCH [HDA Intel PCH], device 7: HDMI 1 [HDMI 1] Subdevices: 1/1 Subdevice #0: subdevice #0 card 0: PCH [HDA Intel PCH], device 8: HDMI 2 [HDMI 2] Subdevices: 1/1 Subdevice #0: subdevice #0 card 0: PCH [HDA Intel PCH], device 9: HDMI 3 [HDMI 3] Subdevices: 1/1 Subdevice #0: subdevice #0 card 0: PCH [HDA Intel PCH], device 10: HDMI 4 [HDMI 4] Subdevices: 1/1 Subdevice #0: subdevice #0輸出
arecord -l（此處未列出數字輸入）：**** List of CAPTURE Hardware Devices **** card 0: PCH [HDA Intel PCH], device 0: CS4207 Analog [CS4207 Analog] Subdevices: 1/1 Subdevice #0: subdevice #0輸出
pacmd list-cards：1 card(s) available. index: 0 name: <alsa_card.pci-0000_00_0e.0> driver: <module-alsa-card.c> owner module: 7 properties: alsa.card = "0" alsa.card_name = "HDA Intel PCH" alsa.long_card_name = "HDA Intel PCH at 0x91410000 irq 143" alsa.driver_name = "snd_hda_intel" device.bus_path = "pci-0000:00:0e.0" sysfs.path = "/devices/pci0000:00/0000:00:0e.0/sound/card0" device.bus = "pci" device.vendor.id = "8086" device.vendor.name = "Intel Corporation" device.product.id = "5a98" device.product.name = "Celeron N3350/Pentium N4200/Atom E3900 Series Audio Cluster" device.form_factor = "internal" device.string = "0" device.description = "Built-in Audio" module-udev-detect.discovered = "1" device.icon_name = "audio-card-pci" profiles: input:analog-stereo: Analog Stereo Input (priority 65, available: unknown) output:analog-stereo: Analog Stereo Output (priority 6500, available: unknown) output:analog-stereo+input:analog-stereo: Analog Stereo Duplex (priority 6565, available: unknown) output:iec958-stereo: Digital Stereo (IEC958) Output (priority 5500, available: unknown) output:iec958-stereo+input:analog-stereo: Digital Stereo (IEC958) Output + Analog Stereo Input (priority 5565, available: unknown) output:hdmi-stereo: Digital Stereo (HDMI) Output (priority 5900, available: no) output:hdmi-stereo+input:analog-stereo: Digital Stereo (HDMI) Output + Analog Stereo Input (priority 5965, available: no) output:hdmi-surround: Digital Surround 5.1 (HDMI) Output (priority 800, available: no) output:hdmi-surround+input:analog-stereo: Digital Surround 5.1 (HDMI) Output + Analog Stereo Input (priority 865, available: no) output:hdmi-surround71: Digital Surround 7.1 (HDMI) Output (priority 800, available: no) output:hdmi-surround71+input:analog-stereo: Digital Surround 7.1 (HDMI) Output + Analog Stereo Input (priority 865, available: no) output:hdmi-stereo-extra1: Digital Stereo (HDMI 2) Output (priority 5700, available: no) output:hdmi-stereo-extra1+input:analog-stereo: Digital Stereo (HDMI 2) Output + Analog Stereo Input (priority 5765, available: no) output:hdmi-surround-extra1: Digital Surround 5.1 (HDMI 2) Output (priority 600, available: no) output:hdmi-surround-extra1+input:analog-stereo: Digital Surround 5.1 (HDMI 2) Output + Analog Stereo Input (priority 665, available: no) output:hdmi-surround71-extra1: Digital Surround 7.1 (HDMI 2) Output (priority 600, available: no) output:hdmi-surround71-extra1+input:analog-stereo: Digital Surround 7.1 (HDMI 2) Output + Analog Stereo Input (priority 665, available: no) output:hdmi-stereo-extra2: Digital Stereo (HDMI 3) Output (priority 5700, available: no) output:hdmi-stereo-extra2+input:analog-stereo: Digital Stereo (HDMI 3) Output + Analog Stereo Input (priority 5765, available: no) output:hdmi-surround-extra2: Digital Surround 5.1 (HDMI 3) Output (priority 600, available: no) output:hdmi-surround-extra2+input:analog-stereo: Digital Surround 5.1 (HDMI 3) Output + Analog Stereo Input (priority 665, available: no) output:hdmi-surround71-extra2: Digital Surround 7.1 (HDMI 3) Output (priority 600, available: no) output:hdmi-surround71-extra2+input:analog-stereo: Digital Surround 7.1 (HDMI 3) Output + Analog Stereo Input (priority 665, available: no) output:hdmi-stereo-extra3: Digital Stereo (HDMI 4) Output (priority 5700, available: no) output:hdmi-stereo-extra3+input:analog-stereo: Digital Stereo (HDMI 4) Output + Analog Stereo Input (priority 5765, available: no) output:hdmi-surround-extra3: Digital Surround 5.1 (HDMI 4) Output (priority 600, available: no) output:hdmi-surround-extra3+input:analog-stereo: Digital Surround 5.1 (HDMI 4) Output + Analog Stereo Input (priority 665, available: no) output:hdmi-surround71-extra3: Digital Surround 7.1 (HDMI 4) Output (priority 600, available: no) output:hdmi-surround71-extra3+input:analog-stereo: Digital Surround 7.1 (HDMI 4) Output + Analog Stereo Input (priority 665, available: no) output:hdmi-stereo-extra4: Digital Stereo (HDMI 5) Output (priority 5700, available: no) output:hdmi-stereo-extra4+input:analog-stereo: Digital Stereo (HDMI 5) Output + Analog Stereo Input (priority 5765, available: no) output:hdmi-surround-extra4: Digital Surround 5.1 (HDMI 5) Output (priority 600, available: no) output:hdmi-surround-extra4+input:analog-stereo: Digital Surround 5.1 (HDMI 5) Output + Analog Stereo Input (priority 665, available: no) output:hdmi-surround71-extra4: Digital Surround 7.1 (HDMI 5) Output (priority 600, available: no) output:hdmi-surround71-extra4+input:analog-stereo: Digital Surround 7.1 (HDMI 5) Output + Analog Stereo Input (priority 665, available: no) off: Off (priority 0, available: unknown) active profile: <output:analog-stereo+input:analog-stereo> sinks: alsa_output.pci-0000_00_0e.0.analog-stereo/#0: Built-in Audio Analog Stereo sources: alsa_output.pci-0000_00_0e.0.analog-stereo.monitor/#0: Monitor of Built-in Audio Analog Stereo alsa_input.pci-0000_00_0e.0.analog-stereo/#1: Built-in Audio Analog Stereo ports: analog-input-mic: Microphone (priority 8700, latency offset 0 usec, available: no) properties: device.icon_name = "audio-input-microphone" analog-input-linein: Line In (priority 8100, latency offset 0 usec, available: yes) properties: analog-output-lineout: Line Out (priority 9000, latency offset 0 usec, available: no) properties: analog-output-speaker: Speakers (priority 10000, latency offset 0 usec, available: unknown) properties: device.icon_name = "audio-speakers" analog-output-headphones: Headphones (priority 9900, latency offset 0 usec, available: no) properties: device.icon_name = "audio-headphones" iec958-stereo-output: Digital Output (S/PDIF) (priority 0, latency offset 0 usec, available: unknown) properties: hdmi-output-0: HDMI / DisplayPort (priority 5900, latency offset 0 usec, available: no) properties: device.icon_name = "video-display" hdmi-output-1: HDMI / DisplayPort 2 (priority 5800, latency offset 0 usec, available: no) properties: device.icon_name = "video-display" hdmi-output-2: HDMI / DisplayPort 3 (priority 5700, latency offset 0 usec, available: no) properties: device.icon_name = "video-display" hdmi-output-3: HDMI / DisplayPort 4 (priority 5600, latency offset 0 usec, available: no) properties: device.icon_name = "video-display" hdmi-output-4: HDMI / DisplayPort 5 (priority 5500, latency offset 0 usec, available: no) properties: device.icon_name = "video-display"引起我注意的另一件事是
/usr/share/pulseaudio/alsa-mixer/paths/analog-input.conf.common; We explicitly don't want to wrap the following sources: ; ; CD [...] ; Digital/SPDIF現在怎麼辦
那麼有沒有一種簡單的方法可以簡單地啟用 IEC958 擷取設備？
我在哪里或如何獲得目前有效的 alsa 配置以進行修改？
–> 看到這個答案
編輯
CS4207 編解碼器的 SPDIF-In 功能在核心 3.5 和 3.8 之間的某個地方失去了。在此期間，對patch_cirrus.c進行了重大重構。
因此，即使我將 IEC958 輸入的 ALSA 控制項（從核心 3.5 的預設配置複製）添加到目前核心的配置中：
control.67 { iface MIXER name 'IEC958 Capture Switch' value false comment { access 'read write' type BOOLEAN count 1 } } control.68 { iface MIXER name 'IEC958 Capture Default' value '0400000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000' comment { access read type IEC958 count 1 } }我得到回報：
Found hardware: "HDA-Intel" "Cirrus Logic CS4207" "HDA:10134207,10134207,00100302 HDA:8086280a,80860101,00100000" "0x8086" "0x7270" Hardware is initialized using a generic method alsactl: set_control:1325: failed to obtain info for control #67 (No such file or directory) alsactl: set_control:1325: failed to obtain info for control #68 (No such file or directory)所以看起來 hda-driver 沒有向系統提供 SPDIF 輸入。因此，問題不再與 ALSA 配置有關，而是與 hda-driver 相關。
使 SPDIF-In 可用
主要問題是 snd_hda 框架目前只支持1 個數字輸入引腳，而 CS4207 有 3 個。
在解析編解碼器引腳期間，它們三個都通過循環，最後一個獲勝並呈現給 ALSA。訣竅是沒有任何配置連接的引腳會在循環中被跳過。
通常引腳配置由 BIOS 設置。由於我們不控制此設置中的 BIOS，因此這不是一個選項。
另一種選擇是使用更新檔文件設置管腳配置（如“早期更新檔”部分所述）。
為此，在這種情況下，我需要引腳節點 ID
0x0E，0x12並讀取它們目前的引腳配置：# hda-verb /dev/snd/hwC0D0 0x0e GET_CONFIG_DEFAULT 0x00 nid = 0xe, verb = 0xf1c, param = 0x0 value = 0xb7d6003e # hda-verb /dev/snd/hwC0D0 0x12 GET_CONFIG_DEFAULT 0x00 nid = 0x12, verb = 0xf1c, param = 0x0 value = 0xb7d6005e選擇
# cat /sys/class/sound/hwC0D0/init_pin_configs 0x09 0x022140f0 0x0a 0x010140f0 0x0b 0x901700f0 0x0c 0x01813051 0x0d 0x01a19031 0x0e 0xb7d6003e 0x0f 0x02c4e0f0 0x10 0x014460f0 0x12 0xb7d6005e 0x15 0x014510f0然後將配置中的前 2 位更改為“無連接”（
01）。配置位的含義記錄在HDA 規範 7.3.3.31 Configuration Default中。所以
0x0e 0xb7d6003e->0x0e 0x77d6003e和0x12 0xb7d6005e->0x12 0xb7d6005e。
/lib/firmware/patch_cs4207使用這些值可以創建一個更新檔文件，例如具有以下內容：[codec] 0x10134207 0x10134207 0 [pincfg] 0x0e 0x77d6003e 0x12 0x77d6005e在下面
$$ codec $$需要列出 vendor_id、subsystem_id 和地址。 之後，更新檔文件需要由 snd_hda_intel 載入。為此，需要將以下行添加到
/etc/modprobe.d/alsa-base.conf：options snd-hda-intel patch=patch_cs4207重新啟動後，無需進一步調整 ALSA，並且 SPDIF-In 被辨識：
# arecord -l **** List of CAPTURE Hardware Devices **** card 0: PCH [HDA Intel PCH], device 0: CS4207 Analog [CS4207 Analog] Subdevices: 1/1 Subdevice #0: subdevice #0 card 0: PCH [HDA Intel PCH], device 1: CS4207 Digital [CS4207 Digital] Subdevices: 0/1 Subdevice #0: subdevice #0
有關其他（與 ALSA 無關的）問題，請參閱原始文章中的 EDIT
回答關於 ALSA 配置的原始問題：
看來這
alsa-info也是最好的地方。根據該腳本，您可以通過以下方式保存目前有效的 ALSA 確認：
alsactl -f /tmp/alsa-config.txt store之後可以在文件中更改配置（在這種情況下
/tmp/alsa-config.txt），並且可以通過以下方式恢復配置alsactl -f /tmp/alsa-config.txt restore此外，目前有效的 ALSA 配置預設儲存在
/var/lib/alsa/asound.state