RE: [PATCH V2 1/2] ASoC: max98363: add soundwire amplifier driver

[Lee, RyanS]

> -----Original Message-----
> From: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
> Sent: Monday, March 13, 2023 7:47 AM
> To: “Ryan <ryan.lee.analog@xxxxxxxxx>; lgirdwood@xxxxxxxxx;
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> Subject: Re: [PATCH V2 1/2] ASoC: max98363: add soundwire amplifier driver
> 
> [External]
> 
> 
> > +	ret = sdw_stream_add_slave(max98363->slave, &stream_config,
> > +				   &port_config, 1, stream);
> > +	if (ret) {
> > +		dev_err(dai->dev, "Unable to configure port\n");
> > +		return ret;
> > +	}
> > +
> > +	if (params_channels(params) > 16) {
> > +		dev_err(component->dev, "Unsupported channels %d\n",
> > +			params_channels(params));
> > +		return -EINVAL;
> > +	}
> 
> Do you actually support more than 8 channels?
> 
> The data port DPnPrepareCtl and DPn_ChannelEn registers expose 8
> channels max. It's always possible to 'cheat' by packing two channels in the
> same sample, but that would require custom signaling between manager and
> peripheral that isn't present.
> 
> Could it be a left-over from a TDM implementation?

Thanks for the comment.
I think it is a left-over from a TDM implementation.
I shall modify the code to accept only max number of channels supported by the amp.

> 
> The rest of the patch looks fine.