Hi,

On Tue, Jul 21, 2026 at 08:41:14AM +0200, Igor Paunovic wrote:
> The Synopsys HDMI RX controller exposes two digital audio interfaces,
> one for I2S (0) and one for S/PDIF (1). Add the #sound-dai-cells
> property so audio cards can reference them as a codec, as documented
> by the snps,dw-hdmi-rx binding.
> 
> Add a shared simple-audio-card routing the receiver I2S DAI to
> i2s7_8ch, the receive-only I2S interface dedicated to HDMI RX, with
> the receiver as bitclock and frame master. The card is named
> "RK3588 HDMI-IN", which is what users see in alsamixer and what ALSA
> UCM matches on. It mirrors the existing HDMI TX sound cards in this
> file and is disabled by default, since not every RK3588 board routes
> HDMI RX audio; boards that do only need to flip its status.
> 
> Signed-off-by: Igor Paunovic <royalnet026@gmail.com>
> ---

Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>

-- Sebastian

> Changes in v4 (both suggested by Sebastian Reichel):
> - define the whole sound card here as a shared, disabled-by-default
>   node mirroring the HDMI TX cards, instead of per board
> - name the card "RK3588 HDMI-IN": the name is user-visible in
>   alsamixer and matched by ALSA UCM
> 
> New in v3 (as "add #sound-dai-cells to the RK3588 HDMI receiver").
>  arch/arm64/boot/dts/rockchip/rk3588-extra.dtsi | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/rockchip/rk3588-extra.dtsi b/arch/arm64/boot/dts/rockchip/rk3588-extra.dtsi
> index a264001..e0dce15 100644
> --- a/arch/arm64/boot/dts/rockchip/rk3588-extra.dtsi
> +++ b/arch/arm64/boot/dts/rockchip/rk3588-extra.dtsi
> @@ -23,6 +23,23 @@
>  		};
>  	};
>  
> +	hdmi_receiver_sound: hdmi-receiver-sound {
> +		compatible = "simple-audio-card";
> +		simple-audio-card,format = "i2s";
> +		simple-audio-card,name = "RK3588 HDMI-IN";
> +		simple-audio-card,bitclock-master = <&hdmiin_codec>;
> +		simple-audio-card,frame-master = <&hdmiin_codec>;
> +		status = "disabled";
> +
> +		hdmiin_codec: simple-audio-card,codec {
> +			sound-dai = <&hdmi_receiver 0>;
> +		};
> +
> +		simple-audio-card,cpu {
> +			sound-dai = <&i2s7_8ch>;
> +		};
> +	};
> +
>  	reserved-memory {
>  		#address-cells = <2>;
>  		#size-cells = <2>;
> @@ -338,6 +355,7 @@
>  		reset-names = "axi", "apb", "ref", "biu";
>  		rockchip,grf = <&sys_grf>;
>  		rockchip,vo1-grf = <&vo1_grf>;
> +		#sound-dai-cells = <1>;
>  		status = "disabled";
>  	};
>  
> -- 
> 2.53.0
>