Introduce 'unconfigure' callback

The 'unconfigure' callback can be used to clean up the 'configured'
state of an Audio Path, for when it is desired to reset the streams,
and/or reload a different stream configuration.

To destroy the streams, we must attempt to force their PCMs
closed. Take note though, that if a PCM is being written to when
an unconfigure command is issued, system instability may occur.

Signed-off-by: Mark Farrugia <mark.farrugia@fiberdyne.com.au>

1 files changed, 51 insertions, 0 deletions

diff --git a/core.c b/core.c
index d9e264c..c2e32c5 100644
--- a/core.c
+++ b/core.c
@@ -112,6 +112,30 @@ static struct snd_pcm *snd_avirt_pcm_create(struct snd_avirt_stream *stream)
 	return pcm;
 }
 
+void snd_avirt_stream_try_destroy(struct snd_avirt_stream *stream)
+{
+	unsigned long _flags;
+	struct snd_pcm_substream *substream =
+		stream->pcm->streams[stream->direction].substream;
+
+	snd_pcm_stream_lock_irqsave(substream, _flags);
+	if (substream->runtime) {
+		if (snd_pcm_running(substream)) {
+			if (0 !=
+			    snd_pcm_stop(substream, SNDRV_PCM_STATE_SUSPENDED))
+				D_ERRORK("Could not stop PCM '%s'",
+					 stream->name);
+		}
+	}
+	snd_pcm_stream_unlock_irqrestore(substream, _flags);
+
+	snd_device_free(core.card, stream->pcm);
+	kfree(stream->pcm_ops);
+	kfree(stream);
+
+	core.stream_count--;
+}
+
 static struct snd_avirt_route *snd_avirt_route_get(const char *uid)
 {
 	struct list_head *entry;
@@ -620,6 +644,33 @@ int snd_avirt_streams_configure(void)
 	return err;
 }
 
+int snd_avirt_streams_unconfigure(void)
+{
+	int i = 0, err = 0;
+	struct snd_avirt_audiopath_obj *ap_obj;
+	struct snd_avirt_stream_array stream_array;
+
+	if (!core.streams_configured) {
+		D_ERRORK("streams are already unconfigured!");
+		return -1;
+	}
+
+	list_for_each_entry (ap_obj, &audiopath_list, list) {
+		if (!ap_obj->path->unconfigure) {
+			D_ERRORK("Cannot do 'unconfigure' for AP: %s",
+				 ap_obj->path->uid);
+			return -EFAULT;
+		}
+
+		D_INFOK("Do 'unconfigure' for AP: %s", ap_obj->path->uid);
+		ap_obj->path->unconfigure();
+	}
+
+	core.streams_configured = false;
+
+	return 0;
+}
+
 bool snd_avirt_streams_configured(void)
 {
 	return core.streams_configured;