[alsa-devel] [RFC PATCH 31/40] soundwire: intel: move shutdown() callback and don't export symbol

[Pierre-Louis Bossart]

On 7/26/19 5:38 AM, Cezary Rojewski wrote:
> On 2019-07-26 01:40, Pierre-Louis Bossart wrote:
>> +void intel_shutdown(struct snd_pcm_substream *substream,
>> +            struct snd_soc_dai *dai)
>> +{
>> +    struct sdw_cdns_dma_data *dma;
>> +
>> +    dma = snd_soc_dai_get_dma_data(dai, substream);
>> +    if (!dma)
>> +        return;
>> +
>> +    snd_soc_dai_set_dma_data(dai, substream, NULL);
>> +    kfree(dma);
>> +}
> 
> Correct me if I'm wrong, but do we really need to _get_dma_ here?
> _set_dma_ seems bulletproof, same for kfree.

I must admit I have no idea why we have a reference to DMAs here, this 
looks like an abuse to store a dai-specific context, and the initial 
test looks like copy-paste to detect invalid configs, as done in other 
callbacks. Vinod and Sanyog might have more history than me here.