From: Russell King - ARM Linux <linux@arm.linux.org.uk>
Date: Thu, 31 Oct 2013 15:09:20 +0000 (+0000)
Subject: ASoC: dpcm: improve robustness
X-Git-Url: http://git.efficios.com/?a=commitdiff_plain;h=2062b4c5d2d8fa47dc89105464e67a7ba310c9e7;p=deliverable%2Flinux.git

ASoC: dpcm: improve robustness

Avoid oopsing if there is no backend stream associated with a front end
stream.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Mark Brown <broonie@linaro.org>
---

diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c
index d81b79251760..591f0f3074c5 100644
--- a/sound/soc/soc-pcm.c
+++ b/sound/soc/soc-pcm.c
@@ -1038,6 +1038,12 @@ static int dpcm_be_dai_startup(struct snd_soc_pcm_runtime *fe, int stream)
 		struct snd_pcm_substream *be_substream =
 			snd_soc_dpcm_get_substream(be, stream);
 
+		if (!be_substream) {
+			dev_err(be->dev, "ASoC: no backend %s stream\n",
+				stream ? "capture" : "playback");
+			continue;
+		}
+
 		/* is this op for this BE ? */
 		if (!snd_soc_dpcm_be_can_update(fe, be, stream))
 			continue;
@@ -1055,7 +1061,8 @@ static int dpcm_be_dai_startup(struct snd_soc_pcm_runtime *fe, int stream)
 		    (be->dpcm[stream].state != SND_SOC_DPCM_STATE_CLOSE))
 			continue;
 
-		dev_dbg(be->dev, "ASoC: open BE %s\n", be->dai_link->name);
+		dev_dbg(be->dev, "ASoC: open %s BE %s\n",
+			stream ? "capture" : "playback", be->dai_link->name);
 
 		be_substream->runtime = be->dpcm[stream].runtime;
 		err = soc_pcm_open(be_substream);