[alsa-devel] [PATCH v3] ALSA: pcm: Return 0 when size < start_threshold in capture

Ricardo Biehl Pasquali pasqualirb at gmail.com
Sat Aug 25 21:53:23 CEST 2018


In __snd_pcm_lib_xfer(), when capture, if state is PREPARED
and size is less than start_threshold nothing can be done.
As there is no error, 0 is returned.

Signed-off-by: Ricardo Biehl Pasquali <pasqualirb at gmail.com>
---

version 3:
Set 'err' variable inside 'else' block.

--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -2173,11 +2173,16 @@ snd_pcm_sframes_t __snd_pcm_lib_xfer(str
 		goto _end_unlock;
 
 	if (!is_playback &&
-	    runtime->status->state == SNDRV_PCM_STATE_PREPARED &&
-	    size >= runtime->start_threshold) {
-		err = snd_pcm_start(substream);
-		if (err < 0)
+	    runtime->status->state == SNDRV_PCM_STATE_PREPARED) {
+		if (size >= runtime->start_threshold) {
+			err = snd_pcm_start(substream);
+			if (err < 0)
+				goto _end_unlock;
+		} else {
+			/* nothing to do */
+			err = 0;
 			goto _end_unlock;
+		}
 	}
 
 	runtime->twake = runtime->control->avail_min ? : 1;


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