Re: [PATCH 11/13] ARM: dts: stm32: fix LTDC port node on STM32 MCU ad MPU

From: Marek Vasut <marex@denx.de>
To: Alexandre Torgue <alexandre.torgue@foss.st.com>,
	arnd@arndb.de, robh+dt@kernel.org, jagan@amarulasolutions.com,
	Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>,
	Marcin Sloniewski <marcin.sloniewski@gmail.com>,
	Ahmad Fatoum <a.fatoum@pengutronix.de>
Cc: linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org,
	linux-stm32@st-md-mailman.stormreply.com,
	linux-kernel@vger.kernel.org, Lee Jones <lee.jones@linaro.org>,
	kuba@kernel.org
Subject: Re: [PATCH 11/13] ARM: dts: stm32: fix LTDC port node on STM32 MCU ad MPU
Date: Thu, 15 Apr 2021 15:21:26 +0200	[thread overview]
Message-ID: <3b39908b-a263-a5d4-f6ac-ac30ffb06269@denx.de> (raw)
In-Reply-To: <20210415101037.1465-12-alexandre.torgue@foss.st.com>

On 4/15/21 12:10 PM, Alexandre Torgue wrote:
> Running "make dtbs_check W=1", some warnings are reported concerning
> LTDC port subnode:
> 
> /soc/display-controller@5a001000/port:
> unnecessary #address-cells/#size-cells without "ranges" or child "reg"
> property
> /soc/display-controller@5a001000/port: graph node has single child node
> 'endpoint', #address-cells/#size-cells are not necessary

btw could you retain diffstat on your patches ? It's useful to see which 
files changed right away.

[...]

> diff --git a/arch/arm/boot/dts/stm32mp157c-dk2.dts b/arch/arm/boot/dts/stm32mp157c-dk2.dts
> index 2bc92ef3aeb9..19ef475a48fc 100644
> --- a/arch/arm/boot/dts/stm32mp157c-dk2.dts
> +++ b/arch/arm/boot/dts/stm32mp157c-dk2.dts
> @@ -82,9 +82,15 @@
>   };
>   
>   &ltdc {
> -	status = "okay";
> -
>   	port {
> +		#address-cells = <1>;
> +		#size-cells = <0>;
> +
> +		ltdc_ep0_out: endpoint@0 {
> +			reg = <0>;
> +			remote-endpoint = <&sii9022_in>;
> +		};
> +
>   		ltdc_ep1_out: endpoint@1 {
>   			reg = <1>;
>   			remote-endpoint = <&dsi_in>;

[...]

> diff --git a/arch/arm/boot/dts/stm32mp15xx-dhcor-avenger96.dtsi b/arch/arm/boot/dts/stm32mp15xx-dhcor-avenger96.dtsi
> index 64dca5b7f748..e7f10975cacf 100644
> --- a/arch/arm/boot/dts/stm32mp15xx-dhcor-avenger96.dtsi
> +++ b/arch/arm/boot/dts/stm32mp15xx-dhcor-avenger96.dtsi
> @@ -277,11 +277,7 @@
>   	status = "okay";
>   
>   	port {
> -		#address-cells = <1>;
> -		#size-cells = <0>;
> -
> -		ltdc_ep0_out: endpoint@0 {
> -			reg = <0>;
> +		ltdc_ep0_out: endpoint {
>   			remote-endpoint = <&adv7513_in>;
>   		};
>   	};

I think this is wrong, the AV96 can have two displays connected to two 
ports of the LTDC, just like DK2 for example.