Re: [PATCH v5 2/2] arm64: dts: ti: k3-am62l3-evm: Add HDMI support

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Medium] dts: missing reset-gpios in sii9022 HDMI bridge node
- [Medium] dts: unmanaged VOUT0_FET_SEL0 multiplexer signal
--

commit 4ee6007c0b1e46ee93bc1bd222e57649c25a3e88
Author: Devarsh Thakkar <devarsht@ti.com>

arm64: dts: ti: k3-am62l3-evm: Add HDMI support

Add the SII9022 HDMI bridge and HDMI connector nodes, along with the
DPI pinmux configuration connecting VOUT0 to the bridge. Enable the DSS
and hook up its DPI output port to the SII9022 bridge input, and the
bridge output to the HDMI connector.

> diff --git a/arch/arm64/boot/dts/ti/k3-am62l3-evm.dts b/arch/arm64/boot/dts/ti/k3-am62l3-evm.dts
> index 84a0cfaaf196a..8ff7c4baaadba 100644
> --- a/arch/arm64/boot/dts/ti/k3-am62l3-evm.dts
> +++ b/arch/arm64/boot/dts/ti/k3-am62l3-evm.dts

[ ... ]

> @@ -192,6 +208,41 @@ exp2: gpio@23 {
>  		bootph-all;
>  	};
>  
> +	sii9022: bridge-hdmi@3b {
> +		compatible = "sil,sii9022";
> +		reg = <0x3b>;
> +		interrupt-parent = <&exp1>;
> +		interrupts = <20 IRQ_TYPE_EDGE_FALLING>;

[Severity: Medium]
The exp2 IO expander defines GPIO_HDMI_RSTn on this board, which defaults to a
high-impedance input on power-up. Should this node define the reset-gpios
property to map and drive that line?

Without explicitly mapping and driving this line via reset-gpios, the HDMI
bridge may remain in reset or an undefined state. This could prevent the driver
from satisfying the hardware's reset timing requirements, potentially causing
I2C probe failures or non-functional HDMI output.

> +		#sound-dai-cells = <0>;
> +		sil,i2s-data-lanes = < 0 >;
> +		bootph-all;

[ ... ]

> @@ -221,6 +272,41 @@ usb_con_hs: endpoint {
>  };
>  
>  &pmx0 {
> +	dpi_pins_default: dpi-default-pins {
> +		pinctrl-single,pins = <
> +			AM62LX_IOPAD(0x00e4, PIN_OUTPUT, 1) /* (L20) GPMC0_CSn0.VOUT0_VSYNC */
> +			AM62LX_IOPAD(0x00dc, PIN_OUTPUT, 1) /* (N21) GPMC0_WPn.VOUT0_HSYNC */

[ ... ]

> +			AM62LX_IOPAD(0x00ec, PIN_INPUT,  5) /* (M23) GPMC0_CSn2.VOUT0_EXTPCLKIN */
> +		>;
> +		bootph-all;
> +	};

[Severity: Medium]
The exp2 IO expander defines a VOUT0_FET_SEL0 signal, which controls the FET
switch for routing the DSS VOUT0/DPI signals on the board. Should this patch
configure that pin (e.g., via a gpio-hog or within a display controller node)?

Since the TCA6424 IO expander defaults to high-impedance inputs, the FET switch
is currently left unmanaged. If the default or floating hardware state does not
route the signals to the HDMI bridge, the hardware path is physically
disconnected and the display will remain blank despite software succeeding.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260923192643.1362891-1-s-jain1@ti.com?part=2