Re: [PATCH v1 2/2] arm64: dts: qcom: qcs6490-rb3gen2: Enable CAN bus controller

[Viken Dadhaniya <viken.dadhaniya@oss.qualcomm.com>]

On 1/9/2026 2:22 PM, Marc Kleine-Budde wrote:
> On 08.01.2026 18:22:00, Viken Dadhaniya wrote:
>> Enable the MCP2518FD CAN controller on the QCS6490 RB3 Gen2 platform.
>> The controller is connected via SPI3 and uses a 40 MHz oscillator.
>> A GPIO hog for GPIO0 is included to configure the CAN transceiver in
>> Normal mode during boot.
>>
>> Signed-off-by: Viken Dadhaniya <viken.dadhaniya@oss.qualcomm.com>
>> ---
>>  arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts | 30 ++++++++++++++++++++
>>  1 file changed, 30 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts b/arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts
>> index e3d2f01881ae..f2f2925e645a 100644
>> --- a/arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts
>> +++ b/arch/arm64/boot/dts/qcom/qcs6490-rb3gen2.dts
>> @@ -44,6 +44,14 @@ chosen {
>>  		stdout-path = "serial0:115200n8";
>>  	};
>>
>> +	clocks {
>> +		mcp2518fd_osc: can-clk {
>> +			compatible = "fixed-clock";
>> +			clock-frequency = <40000000>;
>> +			#clock-cells = <0>;
> 
> Is the #clock-cells property needed?

Yes, #clock-cells is required for all clock providers, including
fixed-clock. For fixed-clock, it must be <0> since there are no arguments.
Omitting it will lead to schema validation errors and may break consumers
expecting a proper clock provider node.

> 
>> +		};
>> +	};
>> +
>>  	dp-connector {
>>  		compatible = "dp-connector";
>>  		label = "DP";
>> @@ -1151,6 +1159,28 @@ platform {
>>  	};
>>  };
>>
>> +&spi3 {
>> +	status = "okay";
>> +
>> +	can@0 {
>> +		compatible = "microchip,mcp2518fd";
>> +		reg = <0>;
>> +		interrupts-extended = <&tlmm 7 IRQ_TYPE_LEVEL_LOW>;
>> +		clocks = <&mcp2518fd_osc>;
>> +		spi-max-frequency = <10000000>;
>> +		vdd-supply = <&vreg_l11c_2p8>;
>> +		gpio-controller;
>> +		#gpio-cells = <2>;
>> +
>> +		gpio0-hog {
>> +			gpio-hog;
>> +			gpios = <0 GPIO_ACTIVE_LOW>;
>> +			output-high;
>> +			line-name = "mcp251xfd-gpio0";
> 
> If the CAN transceiver is connected to GPIO0, why not reflect that in
> the name of the line?

Ack, will update the GPIO line name in v2 to reflect the CAN transceiver
connection.

> 
> Marc
>