ALSA: pcm: Add xrun_injection proc entry

This patch adds a new proc entry for PCM substreams to inject an
XRUN.  When a PCM substream is running and any value is written to its
xrun_injection proc file, the driver triggers XRUN.  This is a useful
feature for debugging XRUN and error handling code paths.

Note that this entry is enabled only when CONFIG_SND_PCM_XRUN_DEBUG is
set.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Iwai
2014-11-04 14:02:40 +01:00
parent f5914908a5
commit 2b30d411db
3 changed files with 40 additions and 0 deletions

View File

@@ -483,6 +483,19 @@ static void snd_pcm_substream_proc_status_read(struct snd_info_entry *entry,
}
#ifdef CONFIG_SND_PCM_XRUN_DEBUG
static void snd_pcm_xrun_injection_write(struct snd_info_entry *entry,
struct snd_info_buffer *buffer)
{
struct snd_pcm_substream *substream = entry->private_data;
struct snd_pcm_runtime *runtime;
snd_pcm_stream_lock_irq(substream);
runtime = substream->runtime;
if (runtime && runtime->status->state == SNDRV_PCM_STATE_RUNNING)
snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
snd_pcm_stream_unlock_irq(substream);
}
static void snd_pcm_xrun_debug_read(struct snd_info_entry *entry,
struct snd_info_buffer *buffer)
{
@@ -614,6 +627,22 @@ static int snd_pcm_substream_proc_init(struct snd_pcm_substream *substream)
}
substream->proc_status_entry = entry;
#ifdef CONFIG_SND_PCM_XRUN_DEBUG
entry = snd_info_create_card_entry(card, "xrun_injection",
substream->proc_root);
if (entry) {
entry->private_data = substream;
entry->c.text.read = NULL;
entry->c.text.write = snd_pcm_xrun_injection_write;
entry->mode = S_IFREG | S_IWUSR;
if (snd_info_register(entry) < 0) {
snd_info_free_entry(entry);
entry = NULL;
}
}
substream->proc_xrun_injection_entry = entry;
#endif /* CONFIG_SND_PCM_XRUN_DEBUG */
return 0;
}
@@ -627,6 +656,10 @@ static int snd_pcm_substream_proc_done(struct snd_pcm_substream *substream)
substream->proc_sw_params_entry = NULL;
snd_info_free_entry(substream->proc_status_entry);
substream->proc_status_entry = NULL;
#ifdef CONFIG_SND_PCM_XRUN_DEBUG
snd_info_free_entry(substream->proc_xrun_injection_entry);
substream->proc_xrun_injection_entry = NULL;
#endif
snd_info_free_entry(substream->proc_root);
substream->proc_root = NULL;
return 0;