[PATCH 3.16.y-ckt 078/180] ASoC: compress: Fix compress device direction check

[Luis Henriques]

3.16.7-ckt24 -stable review patch.  If anyone has any objections, please let me know.

---8<------------------------------------------------------------

From: Vinod Koul <vinod.koul at intel.com>

commit a1068045883ed4a18363a4ebad0c3d55e473b716 upstream.

The detection of direction for compress was only taking into account codec
capabilities and not CPU ones. Fix this by checking the CPU side capabilities
as well

Tested-by: Ashish Panwar <ashish.panwar at intel.com>
Signed-off-by: Vinod Koul <vinod.koul at intel.com>
Signed-off-by: Mark Brown <broonie at kernel.org>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 sound/soc/soc-compress.c | 23 ++++++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/sound/soc/soc-compress.c b/sound/soc/soc-compress.c
index f6a6eb0834b9..9ffd6009d0ec 100644
--- a/sound/soc/soc-compress.c
+++ b/sound/soc/soc-compress.c
@@ -626,17 +626,34 @@ int soc_new_compress(struct snd_soc_pcm_runtime *rtd, int num)
 	struct snd_pcm *be_pcm;
 	char new_name[64];
 	int ret = 0, direction = 0;
+	int playback = 0, capture = 0;
 
 	/* check client and interface hw capabilities */
 	snprintf(new_name, sizeof(new_name), "%s %s-%d",
 			rtd->dai_link->stream_name, codec_dai->name, num);
 
 	if (codec_dai->driver->playback.channels_min)
+		playback = 1;
+	if (codec_dai->driver->capture.channels_min)
+		capture = 1;
+
+	capture = capture && cpu_dai->driver->capture.channels_min;
+	playback = playback && cpu_dai->driver->playback.channels_min;
+
+	/*
+	 * Compress devices are unidirectional so only one of the directions
+	 * should be set, check for that (xor)
+	 */
+	if (playback + capture != 1) {
+		dev_err(rtd->card->dev, "Invalid direction for compress P %d, C %d\n",
+				playback, capture);
+		return -EINVAL;
+	}
+
+	if(playback)
 		direction = SND_COMPRESS_PLAYBACK;
-	else if (codec_dai->driver->capture.channels_min)
-		direction = SND_COMPRESS_CAPTURE;
 	else
-		return -EINVAL;
+		direction = SND_COMPRESS_CAPTURE;
 
 	compr = kzalloc(sizeof(*compr), GFP_KERNEL);
 	if (compr == NULL) {