[PATCH AUTOSEL 4.19 051/167] ALSA: pcm: Return 0 when size < start_threshold in capture

[Sasha Levin]

From: Ricardo Biehl Pasquali <pasqual...@gmail.com>

[ Upstream commit 62ba568f7aef4beb0eda945a2b2a91b7a2b8f215 ]

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 <pasqual...@gmail.com>
Signed-off-by: Takashi Iwai <ti...@suse.de>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 sound/core/pcm_lib.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
index 4e6110d778bd2..7f71c2449af5e 100644
--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -2173,11 +2173,16 @@ snd_pcm_sframes_t __snd_pcm_lib_xfer(struct 
snd_pcm_substream *substream,
                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;
-- 
2.20.1