问ALSA snd_pcm_drop()没有清除完整的缓冲区EN什么是缓冲区？ 临时存储区域称为缓冲区。所有标准输入...
但是此时会出现一个问题,就是当长时间不播音后再去播音就会发生线程阻塞,而在发生阻塞的线程中能够导致阻塞的只有snd_pcm_readi语句,于是在网上找到了类似的说明:ALSA:打开和关闭 PCM On-The-Fly(ALSA: Opening and closing PCM On-The-Fly)答案 - 爱码网 (likecs.com),里面提到了两个函数snd_pcm_drop和sn...
snd_pcm_uframes_t (*pointer)(struct snd_pcm_substream *substream); /* 查询当前的硬件指针 */ int (*wall_clock)(struct snd_pcm_substream *substream, struct timespec *audio_ts); /* 通过hw获得audio_tstamp */ int (*copy)(struct snd_pcm_substream *substream, int channel, snd_pcm_uf...
pcm_close() close(pcm->fd) snd_pcm_release() snd_pcm_release_substream() snd_pcm_drop(substream) snd_pcm_stop(substream,SNDRV_PCM_STATE_SETUP) snd_pcm_do_stop() substream->ops->trigger(substream,SNDRV_PCM_TRIGGER_STOP) soc_pcm_trigger() codec_dai->driver->ops->trigger() platform...
struct snd_pcm { struct snd_card *card; /* 指向所属的card设备 */ int device; /* device number */ struct snd_pcm_str streams[2]; /* 播放和录制两个数据流 */ wait_queue_head_t open_wait; /* 打开pcm设备时等待打开一个可获得的substream */ ...
2.2 pcm_open()栈 用户的pcm_open()相当于先对ASoC各个驱动模块startup(),再做hw_params()。 pcm_open()pcm->fd=open("/dev/snd/pcmC0D0c")snd_pcm_capture_open()snd_pcm_open(SNDRV_PCM_STREAM_CAPTURE)snd_pcm_open_file()snd_pcm_open_substream()substream->ops->open()soc_pcm_open()cpu...
"unable to open pcm device: %s\n", snd_...
### 摘要 Advanced Linux Sound Architecture (ALSA) 是 Linux 操作系统的核心音频和 MIDI 功能组件。它不仅高效支持各类音频接口,还提供了强大的音频驱动程序,确保了稳定可靠的音频输出。此外,ALSA 具备灵活的音频处理能力,能够满足专业音频制作及日常使用的需求。其丰富的 API 接口方便开发者进行音频相关应用的开发,...
snd_card_create snd_ctl_create snd_ctl_dev_register创建"controlC%i"声卡对应的控制节点, 他的fops为snd_ctl_f_ops snd_pcm_dev_register snd_register_device_for_dev 创建"pcmC%iD%ip"或者"pcmC%iD%ic"设备节点,它的fops为snd_pcm_f_ops[2] ...
snd_soc_new_pcms snd_card_create snd_ctl_create snd_ctl_dev_register创建"controlC%i"声卡对应的控制节点, 他的fops为snd_ctl_f_ops snd_pcm_dev_register snd_register_device_for_dev 创建"pcmC%iD%ip"或者"pcmC%iD%ic"设备节点,它的fops为snd_pcm_f_ops[2] ...