Re: [PATCH 2/3] arm64: dts: renesas: r8a77995: add R-Car Sound support

From: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Magnus <magnus.damm@gmail.com>,
	Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
	Kazuya Mizuguchi <kazuya.mizuguchi.ks@renesas.com>,
	Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>,
	hoai.luu.ub@renesas.com,
	Takeshi Kihara <takeshi.kihara.df@renesas.com>,
	Harunobu Kurokawa <harunobu.kurokawa.dn@renesas.com>,
	Khiem Nguyen <khiem.nguyen.xt@renesas.com>,
	Hien Dang <hien.dang.eb@renesas.com>
Subject: Re: [PATCH 2/3] arm64: dts: renesas: r8a77995: add R-Car Sound support
Date: 18 May 2021 07:27:16 +0900	[thread overview]
Message-ID: <878s4dc7y3.wl-kuninori.morimoto.gx@renesas.com> (raw)
In-Reply-To: <CAMuHMdXtnSenYk3sE6Pp89YeuUf=RsU5ueOLKX3ip9j1NMBKCQ@mail.gmail.com>

Hi Geert

> > From: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
> >
> > This patch adds R-Car Sound and Audio-DMAC support for D3.
> >
> > 1st note is that D3 doesn't have audio-clk-c, but is
> > required from driver. This patch uses null-clk for it.
> >
> > 2nd note is that D3 has SSI3/4 and SRC5/6 only, but driver
> > requres from SSI0/SRC0. This patch has disabled SSI/SRC for it.
> 
> I think it would be better to fix the driver instead.

We already have this kind of SoC before.
And I guess it has these, but just not counnected.
It is Hardware side condition.

> > +       /*
> > +        * R8A77995 doesn't have audio_clk_c, * but is required from driver.
> > +        * Create NULL clock for it.
> > +        */
> > +       null_clk: null_clk {
> > +               compatible = "fixed-clock";
> > +               #clock-cells = <0>;
> > +               clock-frequency = <0>;
> > +       };
> 
> Please do not add nodes not matching the hardware description, but fix
> the driver instead. ("DT describes hardware, not software policy").

Yeah, I agree.
Will fix driver first, and repost SoC patch, again.

Thank you for your help !!

Best regards
---
Kuninori Morimoto