Re: [PATCH] ASoC: Intel: mrfld: fix incorrect check on p->sink

[Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>]

On 11/19/19 5:36 AM, Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
> 
> The check on p->sink looks bogus, I believe it should be p->source
> since the following code blocks are related to p->source. Fix
> this by replacing p->sink with p->source.
> 
> Addresses-Coverity: ("Copy-paste error")
> Fixes: 24c8d14192cc ("ASoC: Intel: mrfld: add DSP core controls")
> Signed-off-by: Colin Ian King <colin.king@canonical.com>
> ---
> 
> [ Note: this has not been tested ]
> 

wow, nice catch. this dates from October 2014 and was merged in Linux 3.19.

I did look at the entire function and indeed it does not seem logical at 
all and rather an unintentional bad copy-paste, probably undetected 
since changing the gains on capture is less straightforward to test.

	if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
		dev_dbg(dai->dev, "Stream name=%s\n",
				dai->playback_widget->name);
		w = dai->playback_widget;
		snd_soc_dapm_widget_for_each_sink_path(w, p) {
			if (p->connected && !p->connected(w, p->sink))
				continue;
[snip]
		}
	} else {
		dev_dbg(dai->dev, "Stream name=%s\n",
				dai->capture_widget->name);
		w = dai->capture_widget;
		snd_soc_dapm_widget_for_each_source_path(w, p) {
			if (p->connected && !p->connected(w, p->sink))

<< here it doesn't look right to use sink here.

				continue;

This macro snd_soc_dapm_widget_for_each_source_path() is also used in 
the skylake/skl-topology.c but without any source/sink inversion.

I don't think anyone on the Intel side will have time to investigate 
further, and unless someone from the initial contributors states this 
was intentional (Vinod/Sanyog?), we should merge this.

let's see if there's any feedback and if not I'll ack this.


> ---
>   sound/soc/intel/atom/sst-atom-controls.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/sound/soc/intel/atom/sst-atom-controls.c b/sound/soc/intel/atom/sst-atom-controls.c
> index baef461a99f1..f883c9340eee 100644
> --- a/sound/soc/intel/atom/sst-atom-controls.c
> +++ b/sound/soc/intel/atom/sst-atom-controls.c
> @@ -1333,7 +1333,7 @@ int sst_send_pipe_gains(struct snd_soc_dai *dai, int stream, int mute)
>   				dai->capture_widget->name);
>   		w = dai->capture_widget;
>   		snd_soc_dapm_widget_for_each_source_path(w, p) {
> -			if (p->connected && !p->connected(w, p->sink))
> +			if (p->connected && !p->connected(w, p->source))
>   				continue;
>   
>   			if (p->connect &&  p->source->power &&
>