ASoC: soc-compress: Deduce stream direction

Previously we just hard coded all streams as playback streams, this
patch checks the DAI to see if it is a capture or playback stream. It is
worth noting that at this time only unidirectional streams are
supported.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Richard Fitzgerald <rf@opensource.wolfsonmicro.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/soc/soc-compress.c

@@ -384,7 +384,14 @@ int soc_new_compress(struct snd_soc_pcm_runtime *rtd, int num)
 	/* check client and interface hw capabilities */
 	snprintf(new_name, sizeof(new_name), "%s %s-%d",
 			rtd->dai_link->stream_name, codec_dai->name, num);
-	direction = SND_COMPRESS_PLAYBACK;
+
+	if (codec_dai->driver->playback.channels_min)
+		direction = SND_COMPRESS_PLAYBACK;
+	else if (codec_dai->driver->capture.channels_min)
+		direction = SND_COMPRESS_CAPTURE;
+	else
+		return -EINVAL;
+
 	compr = kzalloc(sizeof(*compr), GFP_KERNEL);
 	if (compr == NULL) {
 		snd_printk(KERN_ERR "Cannot allocate compr\n");