Mute ALSA audio completely

chrome/browser/chromeos/audio_mixer_alsa.cc

Index: chrome/browser/chromeos/audio_mixer_alsa.cc
diff --git a/chrome/browser/chromeos/audio_mixer_alsa.cc b/chrome/browser/chromeos/audio_mixer_alsa.cc
index 34fb722ab0e51b9ad098568e9949764a95a530d4..07a6b964e968c8d952c2518a3f2b130ee0291ab9 100644
--- a/chrome/browser/chromeos/audio_mixer_alsa.cc
+++ b/chrome/browser/chromeos/audio_mixer_alsa.cc
@@ -246,6 +246,8 @@ bool AudioMixerAlsa::InitializeAlsaMixer() {
   snd_mixer_t* handle = NULL;
   const char* card = "default";
 
+  PingPCM();

[scherkus (not reviewing), 2011/03/02 19:07:11]

maybe inline this code considering it's not caleld anywhere else and you already
have a bunch of snd_XXX_YYY() functions + error checking + logging

[davejcool, 2011/03/03 20:05:02]

It is remarkably close to the other calls in InitializeAlsaMixer(), so I'm now
inlining instead.

+
   if ((err = snd_mixer_open(&handle, 0)) < 0) {
     LOG(ERROR) << "ALSA mixer " << card << " open error: " << snd_strerror(err);
     return false;
@@ -519,4 +521,17 @@ void AudioMixerAlsa::SetElementMuted_Locked(snd_mixer_elem_t* elem, bool mute) {
   }
 }
 
+void AudioMixerAlsa::PingPCM() {
+  snd_pcm_t* pcm_out_handle;
+  int err;
+  if ((err = snd_pcm_open(&pcm_out_handle,
+                          "default",
+                          SND_PCM_STREAM_PLAYBACK,
+                          0)) >= 0) {
+    snd_pcm_close(pcm_out_handle);
+    return;
+  }
+  LOG(ERROR) << "ALSA PCM open error: " << snd_strerror(err);
+}
+
 }  // namespace chromeos