Re: [PATCH 2/2] soundwire: Intel: add trigger callback

[Greg KH <gregkh@linuxfoundation.org>]

On Fri, Jun 10, 2022 at 10:35:37AM +0800, Bard Liao wrote:
> When a pipeline is split into FE and BE parts, the BE pipeline may need to
> be triggered separately in the BE trigger op. So add the trigger callback
> in the link_res ops that will be invoked during BE DAI trigger.
> 
> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
> Reviewed-by: Rander Wang <rander.wang@intel.com>
> Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
> Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
> ---
>  drivers/soundwire/intel.c           | 8 ++++++++
>  include/linux/soundwire/sdw_intel.h | 1 +
>  2 files changed, 9 insertions(+)
> 
> diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c
> index 808e2f320052..3f3c2c99cb8e 100644
> --- a/drivers/soundwire/intel.c
> +++ b/drivers/soundwire/intel.c
> @@ -1004,9 +1004,17 @@ static int intel_trigger(struct snd_pcm_substream *substream, int cmd, struct sn
>  {
>  	struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai);
>  	struct sdw_intel *sdw = cdns_to_intel(cdns);
> +	struct sdw_intel_link_res *res = sdw->link_res;
>  	struct sdw_cdns_dma_data *dma;
>  	int ret = 0;
>  
> +	/* The .trigger callback is used to send required IPC to audio
> +	 * firmware. The .free_stream callback will still be called
> +	 * by intel_free_stream() in the TRIGGER_SUSPEND case.
> +	 */
> +	if (res->ops && res->ops->trigger)
> +		res->ops->trigger(dai, cmd, substream->stream);
> +
>  	dma = snd_soc_dai_get_dma_data(dai, substream);
>  	if (!dma) {
>  		dev_err(dai->dev, "failed to get dma data in %s\n",
> diff --git a/include/linux/soundwire/sdw_intel.h b/include/linux/soundwire/sdw_intel.h
> index 67e0d3e750b5..f638707fd712 100644
> --- a/include/linux/soundwire/sdw_intel.h
> +++ b/include/linux/soundwire/sdw_intel.h
> @@ -119,6 +119,7 @@ struct sdw_intel_ops {
>  			     struct sdw_intel_stream_params_data *params_data);
>  	int (*free_stream)(struct device *dev,
>  			   struct sdw_intel_stream_free_data *free_data);
> +	int (*trigger)(struct snd_soc_dai *dai, int cmd, int stream);
>  };
>  
>  /**
> -- 
> 2.17.1
> 

Where is the in-kernel user of this new callback?  Without that, there
is no need for this, NOR is there a way to properly review this commit.

sorry,

greg k-h