Re: [v5 3/4] ASoC: mediatek: mt8192: refactor for I2S8/I2S9 DAI links of headset

[Tzung-Bi Shih <tzungbi@kernel.org>]

On Mon, Mar 21, 2022 at 10:38:48PM +0800, Jiaxin Yu wrote:
> On Mon, 2022-03-21 at 17:21 +0800, Tzung-Bi Shih wrote:
> > On Mon, Mar 21, 2022 at 05:14:08PM +0800, Jiaxin Yu wrote:
> > > On Mon, 2022-03-21 at 11:59 +0800, Tzung-Bi Shih wrote:
> > > > On Sat, Mar 19, 2022 at 07:41:10PM +0800, Jiaxin Yu wrote:
> > > > > @@ -1145,6 +1140,13 @@ static int
> > > > > mt8192_mt6359_dev_probe(struct
> > > > > platform_device *pdev)
> > > > >  		goto err_speaker_codec;
> > > > >  	}
> > > > >  
> > > > > +	headset_codec = of_get_child_by_name(pdev->dev.of_node,
> > > > > "mediatek,headset-codec");
> > > > > +	if (!headset_codec) {
> > > > > +		ret = -EINVAL;
> > > > > +		dev_err_probe(&pdev->dev, ret, "Property
> > > > > 'headset_codec' missing or invalid\n");
> > > > > +		goto err_headset_codec;
> > > > > +	}
> > > > 
> > > > (to be neat) Does it have any reason to prevent from using
> > > > of_parse_phandle()
> > > > but of_get_child_by_name()?
> > > 
> > > "mediatek,headset-codec" is a child node of pdev->dev.of_node, so I
> > > use
> > > of_get_child_by_name() to get and   pass it to
> > > snd_soc_of_get_dai_link_codecs().
> > 
> > "mediatek,platform" and "mediatek,hdmi-codec" are also children of
> > pdev->dev.of_node.  I guess my question is: why doesn't it also use
> > of_parse_phandle() for "mediatek,headset-codec"?  Did I
> > misunderstand?
> 
> The following is from bindings, "mediatek,speaker-codec" and
> "mediatek,headset-codec" are sub nodes of sound but "mediatek,platform"
> and "mediatek,hdmi-codec" are the name of properties. So we can't get
> the sub node pointer through of_parse_phandle().
> 
>       sound: mt8192-sound {
>           compatible = "mediatek,mt8192_mt6359_rt1015_rt5682";
>           mediatek,platform = <&afe>;
>           mediatek,hdmi-codec = <&anx_bridge_dp>;
>           pinctrl-names = "aud_clk_mosi_off",
>                           "aud_clk_mosi_on";
>           pinctrl-0 = <&aud_clk_mosi_off>;
>           pinctrl-1 = <&aud_clk_mosi_on>;
>  
>           mediatek,headset-codec {
>               sound-dai = <&rt5682>;
>           };
>  
>           mediatek,speaker-codec {
>               sound-dai = <&rt1015_l>,
>                           <&rt1015_r>;
>           };
>       };

Got it, thanks for the explanation.  Will provide my R-b tag in another
thread.