[alsa-devel] [PATCH] ASoC: compress: Fix compress device direction check

[Takashi Iwai]

On Thu, 07 Jan 2016 09:23:11 +0100,
Vinod Koul wrote:
> 
> The detection of direction for compress takes into account codec
> capabilities only and not the CPU ones. Fix this by checking the
> CPU side capabilities as well.
> 
> Cc: <stable at vger.kernel.org>
> Tested-by: Ashish Panwar <ashish.panwar at intel.com>
> Signed-off-by: Vinod Koul <vinod.koul at intel.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 12a9820feac1..b5737945bcc3 100644
> --- a/sound/soc/soc-compress.c
> +++ b/sound/soc/soc-compress.c
> @@ -630,6 +630,7 @@ int snd_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;
>  
>  	if (rtd->num_codecs > 1) {
>  		dev_err(rtd->card->dev, "Multicodec not supported for compressed stream\n");
> @@ -641,11 +642,27 @@ int snd_soc_new_compress(struct snd_soc_pcm_runtime *rtd, int num)
>  			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)) {

I don't think this can catch the case where both playback and capture
are set.  You need really use XOR operator for that.  Or, something
like:
	if (playback + capture != 1) {
		....


Takashi