USB 音效卡驅動

交叉編譯 Linux kernel

編譯參數

在原編譯檔 .config 的 General setup 上方加上 CONFIG_SOUND=m
注意: 開始編譯後，會出現許多詢問項目，必須輸入 m 或 y

CONFIG_SOUND=m
#
# General setup
#
..... 

Advanced Linux Sound Architecture (SND) [N/m/?] (NEW) m

 Sequencer support (SND_SEQUENCER) [N/m/?] (NEW) m
    Sequencer dummy client (SND_SEQ_DUMMY) [N/m/?] (NEW) m
  OSS Mixer API (SND_MIXER_OSS) [N/m/?] (NEW) m
  OSS PCM (digital audio) API (SND_PCM_OSS) [N/m/?] (NEW) m
  OSS PCM (digital audio) API - Include plugin system (SND_PCM_OSS_PLUGINS) [Y/n/?] (NEW) y
  OSS Sequencer API (SND_SEQUENCER_OSS) [N/y/?] (NEW) y
  Dynamic device file minor numbers (SND_DYNAMIC_MINORS) [N/y/?] (NEW) y
  Support old ALSA API (SND_SUPPORT_OLD_API) [Y/n/?] (NEW) y
  Verbose procfs contents (SND_VERBOSE_PROCFS) [Y/n/?] (NEW) y
  Verbose printk (SND_VERBOSE_PRINTK) [N/y/?] (NEW) n
 Debug (SND_DEBUG) [N/y/?] (NEW) n

  *
  * Generic devices
  *
  Dummy (/dev/null) soundcard (SND_DUMMY) [N/m/?] (NEW) m
  Virtual MIDI soundcard (SND_VIRMIDI) [N/m/?] (NEW) m
  MOTU MidiTimePiece AV multiport MIDI (SND_MTPAV) [N/m/?] (NEW) n
  UART16550 serial MIDI driver (SND_SERIAL_U16550) [N/m/?] (NEW) n
  Generic MPU-401 UART driver (SND_MPU401) [N/m/?] (NEW) n

*
* USB devices
*
USB Audio/MIDI driver (SND_USB_AUDIO) [N/m/?] (NEW) m
Native Instruments USB audio devices (SND_USB_CAIAQ) [N/m/?] (NEW) n
 

*
* System on Chip audio support
*
ALSA for SoC audio support (SND_SOC) [N/m/?] (NEW) m
*
* STMicroelectronics SoCs support
*
STMicroelectronics SoCs support (SND_STM) [N/m/?] (NEW) m
  Name of BPA2 partition to allocate buffers from (SND_STM_BPA2_PARTITION_NAME) [audio] (NEW)
  STx7100 and STx7109 support (SND_STM_STX710X) [N/m/?] (NEW) m
  STx7105 support (SND_STM_STX7105) [M/n/?] (NEW) m
  STx7111 support (SND_STM_STX7111) [N/m/?] (NEW) m
  STx7141 support (SND_STM_STX7141) [N/m/?] (NEW) m
  STx7200 support (SND_STM_STX7200) [N/m/?] (NEW) m
  Dummy converter driver (SND_STM_CONV_DUMMY) [N/m/?] (NEW) m
  Generic GPIO-controlled converter driver (SND_STM_CONV_GPIO) [N/m/?] (NEW) m
  Generic I2C-controlled converter driver (SND_STM_CONV_I2C) [N/m/?] (NEW) m

*
* Open Sound System
*
Open Sound System (DEPRECATED) (SOUND_PRIME) [N/m/?] (NEW) n

開始編譯

make ARCH=sh CROSS_COMPILE=sh4-linux- vmlinux
make ARCH=sh CROSS_COMPILE=sh4-linux- modules
make ARCH=sh CROSS_COMPILE=sh4-linux- modules_install INSTALL_MOD_PATH=./modules_install

make the vmlinux.ub

sh4-linux-objcopy -O binary vmlinux vmlinux.bin
gzip --best --force vmlinux.bin
mkimage -A sh -O linux -T kernel -C gzip -a 0x80800000 -e 0x80801000 -n "Linux 2.6" -d vmlinux.bin.gz vmlinux.ub

交叉編譯 ALSA-Lib 與 ALSA-Utils 套件

套件下載: http://www.alsa-project.org/main/index.php/Download

alsa-lib

CC=sh4-linux-gcc \
./configure --host=sh4-linux

make
make install DESTDIR=/home/alang/STLinux_Cross-Compile/build_opt/alsa-lib

alsa-utils

CC=sh4-linux-gcc \
./configure --host=sh4-linux

make
make install DESTDIR=/home/alang/STLinux_Cross-Compile/build_opt/alsa-utils

安裝 ALSA 驅動模組

安裝模組檔至以下目錄
/lib/modules/2.6.23.17_stm23_A18B-PDK7105-32BITS-A18B/kernel/sound

啟動模組
modprobe soundcore
modprobe snd-usb-audio
modprobe snd-pcm-oss
modprobe snd_seq_midi
modprobe snd_seq_oss 

TIP:

如果啟動失敗，必須執行 depmod -a

檢視安裝後的模組列表

root@localhost:/dev/snd# lsmod | grep snd
soundcore               6468  1 snd
snd                    49972  7 snd_usb_audio,snd_pcm,snd_timer,snd_usb_lib,snd_rawmidi,snd_seq_device,snd_hwdep
snd_hwdep               7492  1 snd_usb_audio
snd_seq_device          6860  1 snd_rawmidi
snd_rawmidi            22496  1 snd_usb_lib
snd_timer              21060  1 snd_pcm
snd_pcm                78373  1 snd_usb_audio
snd_page_alloc          6376  1 snd_pcm
snd_usb_lib            15712  1 snd_usb_audio
snd_usb_audio          80128  0

新增 /etc/modprobe.conf (非必要)

# ALSA portion
alias char-major-116 snd
alias snd-card-0 snd-usb-audio
options snd-usb-audio nrpacks=1

# OSS/Free portion
alias char-major-14 soundcore
alias sound-slot-0 snd-card-0

# card #1
alias sound-service-0-0 snd-mixer-oss
alias sound-service-0-1 snd-seq-oss
alias sound-service-0-3 snd-pcm-oss
alias sound-service-0-12 snd-pcm-oss

TIPs:

加上 modprobe.conf 後，只要執行 APP 例如 aplay  -l，系統就會自動載入需要的模組。

建立 alsa.conf
從套件 alsa-lib 的目錄<alsa-lib>/usr/share/alsa/alsa.conf 複製到 /usr/share/alsa/alsa.conf

以下是測試用的簡易 alsa.conf：

pcm.!default {
   type hw
   card 0
}
pcm.hw {
   type hw
   card 0
   device 0
   subdevice 0
}
ctl.!default {
   type hw
   card 0
}
ctl.hw {
   type hw
   card 0
}

新增裝置檔

新增群組 audio

vi /etc/group
加上這一行
audio:*:1000:

解壓附件檔案 dev_snd_all.tar.gz

mkdir /dev/snd
chmod 0755 /dev/snd
tar xzf dev_snd_all.tar.gz -C /dev/snd

安裝以後

root@localhost:/dev/snd# ls -l /dev/snd
crw-rw----    1 root     audio    116,   5 Jan  1  2000 controlC0
crw-rw-rw-    1 root     audio    116,  32 Feb 24 16:56 controlC1
crw-rw----    1 root     audio    116,   4 Jan  1  2000 pcmC0D0c
crw-rw----    1 root     audio    116,   3 Jan  1  2000 pcmC0D0p
crw-rw-rw-    1 root     audio    116,  25 Feb 24 16:56 pcmC0D1c
crw-rw-rw-    1 root     audio    116,  17 Feb 24 16:56 pcmC0D1p
crw-rw-rw-    1 root     audio    116,  26 Feb 24 16:56 pcmC0D2c
crw-rw-rw-    1 root     audio    116,  18 Feb 24 16:56 pcmC0D2p
crw-rw----    1 root     audio    116,   1 Feb 24 16:56 seq
crw-rw----    1 root     audio    116,   2 Jan  1  2000 timer

Q&A

參考連結

• http://alsa.opensrc.org/AlsaBuild2.6
• http://alsa.opensrc.org/TroubleShooting
• http://snowwolf725.blogspot.tw/