[ALSA] Clean up PCM codes (take 2)

- Clean up initialization and destruction of substream instance
  Now snd_pcm_open_substream() alone does most initialization jobs.
  Add pcm_release callback for cleaning up at snd_pcm_release_substream()
- Tidy up PCM oss code

Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 6 insertions, 6 deletions

diff --git a/sound/core/pcm.c b/sound/core/pcm.c
index 1e9878fed37f..5d7eb123b999 100644
--- a/sound/core/pcm.c
+++ b/sound/core/pcm.c
@@ -777,8 +777,9 @@ static void snd_pcm_tick_timer_func(unsigned long data)
         snd_pcm_tick_elapsed(substream);
 }
 
-int snd_pcm_open_substream(struct snd_pcm *pcm, int stream,
-                           struct snd_pcm_substream **rsubstream)
+int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream,
+                             struct file *file,
+                             struct snd_pcm_substream **rsubstream)
 {
         struct snd_pcm_str * pstr;
         struct snd_pcm_substream *substream;
@@ -793,7 +794,7 @@ int snd_pcm_open_substream(struct snd_pcm *pcm, int stream,
         *rsubstream = NULL;
         snd_assert(pcm != NULL, return -ENXIO);
         pstr = &pcm->streams[stream];
-        if (pstr->substream == NULL)
+        if (pstr->substream == NULL || pstr->substream_count == 0)
                 return -ENODEV;
 
         card = pcm->card;
@@ -807,8 +808,6 @@ int snd_pcm_open_substream(struct snd_pcm *pcm, int stream,
         }
         up_read(&card->controls_rwsem);
 
-        if (pstr->substream_count == 0)
-                return -ENODEV;
         switch (stream) {
         case SNDRV_PCM_STREAM_PLAYBACK:
                 if (pcm->info_flags & SNDRV_PCM_INFO_HALF_DUPLEX) {
@@ -874,12 +873,13 @@ int snd_pcm_open_substream(struct snd_pcm *pcm, int stream,
 
         substream->runtime = runtime;
         substream->private_data = pcm->private_data;
+        substream->ffile = file;
         pstr->substream_opened++;
         *rsubstream = substream;
         return 0;
 }
 
-void snd_pcm_release_substream(struct snd_pcm_substream *substream)
+void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
 {
         struct snd_pcm_runtime *runtime;
         substream->file = NULL;