Re: [PATCH v5 2/3] arm64: dts: rockchip: Add HDMI0 audio output for rk3588 SoC

From: Detlev Casanova <detlev.casanova@collabora.com>
To: linux-kernel@vger.kernel.org, Quentin Schulz <quentin.schulz@cherry.de>
Cc: Rob Herring <robh@kernel.org>,
	Krzysztof Kozlowski <krzk+dt@kernel.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Heiko Stuebner <heiko@sntech.de>,
	Andrzej Hajda <andrzej.hajda@intel.com>,
	Neil Armstrong <neil.armstrong@linaro.org>,
	Robert Foss <rfoss@kernel.org>,
	Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
	Jonas Karlman <jonas@kwiboo.se>,
	Jernej Skrabec <jernej.skrabec@gmail.com>,
	Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
	Maxime Ripard <mripard@kernel.org>,
	Thomas Zimmermann <tzimmermann@suse.de>,
	David Airlie <airlied@gmail.com>, Simona Vetter <simona@ffwll.ch>,
	Sebastian Reichel <sebastian.reichel@collabora.com>,
	Alexey Charkov <alchark@gmail.com>,
	Cristian Ciocaltea <cristian.ciocaltea@collabora.com>,
	Dragan Simic <dsimic@manjaro.org>,
	Jianfeng Liu <liujianfeng1994@gmail.com>,
	Niklas Cassel <cassel@kernel.org>,
	FUKAUMI Naoki <naoki@radxa.com>,
	Kever Yang <kever.yang@rock-chips.com>,
	Johan Jonker <jbx6244@gmail.com>,
	Geert Uytterhoeven <geert+renesas@glider.be>,
	Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
	Algea Cao <algea.cao@rock-chips.com>,
	Chen-Yu Tsai <wens@csie.org>,
	Sugar Zhang <sugar.zhang@rock-chips.com>,
	devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-rockchip@lists.infradead.org,
	dri-devel@lists.freedesktop.org, kernel@collabora.com
Subject: Re: [PATCH v5 2/3] arm64: dts: rockchip: Add HDMI0 audio output for rk3588 SoC
Date: Thu, 06 Feb 2025 12:17:51 -0500	[thread overview]
Message-ID: <2781606.mvXUDI8C0e@earth> (raw)
In-Reply-To: <bfe9cb98-12ba-484c-95af-e5842edaab76@cherry.de>

On Tuesday, 4 February 2025 05:14:37 EST Quentin Schulz wrote:
> Hi Detlev,
> 
> On 2/3/25 6:16 PM, Detlev Casanova wrote:
> > Use the simple-audio-card driver with the hdmi0 QP node as CODEC and
> > the i2s5 device as CPU.
> > 
> > The simple-audio-card,mclk-fs value is set to 128 as it is done in
> > the downstream driver.
> > 
> > The #sound-dai-cells value is set to 0 in the hdmi0 node so that it can be
> > used as an audio codec node.
> > 
> > Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com>
> > ---
> > 
> >   arch/arm64/boot/dts/rockchip/rk3588-base.dtsi | 17 +++++++++++++++++
> >   1 file changed, 17 insertions(+)
> > 
> > diff --git a/arch/arm64/boot/dts/rockchip/rk3588-base.dtsi
> > b/arch/arm64/boot/dts/rockchip/rk3588-base.dtsi index
> > 8cfa30837ce72..767bdfc06b7ec 100644
> > --- a/arch/arm64/boot/dts/rockchip/rk3588-base.dtsi
> > +++ b/arch/arm64/boot/dts/rockchip/rk3588-base.dtsi
> > @@ -1369,6 +1369,22 @@ i2s9_8ch: i2s@fddfc000 {
> > 
> >   		status = "disabled";
> >   	
> >   	};
> > 
> > +	hdmi0_sound: hdmi0-sound {
> > +		compatible = "simple-audio-card";
> > +		simple-audio-card,format = "i2s";
> > +		simple-audio-card,mclk-fs = <128>;
> > +		simple-audio-card,name = "hdmi0";
> > +		status = "disabled";
> > +
> > +		simple-audio-card,codec {
> > +			sound-dai = <&hdmi0>;
> > +		};
> > +
> > +		simple-audio-card,cpu {
> > +			sound-dai = <&i2s5_8ch>;
> > +		};
> > +	};
> > +
> 
> This is an address/bus-less device, so I believe it needs to be put
> among other address/bus-less devices, which for Rockchip SoCs is at the
> top of the DT? c.f.
> https://www.kernel.org/doc/html/latest/devicetree/bindings/dts-coding-style.
> html
> 
> **I** would put it between the firmware and the pmu-a55 nodes.

I wasn't sure about this. It makes sense to move it with address-less devices, 
but the rk3399 device tree has it above the hdmi node, so I wanted to stay 
consistent with that.

> Tested-by: Quentin Schulz <quentin.schulz@cherry.de> # RK3588 Tiger Haikou
> 
> Thanks!
> Quentin