TCAN4550-Q1: Questions regarding TCAN4550 driver

Hi PY,

The TCAN4550 requires a SPI interface to the processor and has some optional GPIO pins that can also be used.  These include a Reset pin that can reset the TCAN4550 registers to default values, an input signal to indicate whether the device is in an active state, or sleep state, and an output signal to be used to wake up the TCAN4550 if it in a sleep state.

You will need to make sure your bindings correspond to the hardware configuration used between the processor and TCAN4550 device pins.  Some evaluation will be needed to test whether your SPI communication is working properly and that the Reset and other optional GPIO pins are working properly for your bindings.

Additional information about the Device Tree Bindings for the TCAN4x5x driver can be found here:

https://www.kernel.org/doc/Documentation/devicetree/bindings/net/can/tcan4x5x.txt

Texas Instruments TCAN4x5x CAN Controller
================================================

This file provides device node information for the TCAN4x5x interface contains.

Required properties:
	- compatible: "ti,tcan4x5x"
	- reg: 0
	- #address-cells: 1
	- #size-cells: 0
	- spi-max-frequency: Maximum frequency of the SPI bus the chip can
			     operate at should be less than or equal to 18 MHz.
	- interrupt-parent: the phandle to the interrupt controller which provides
                    the interrupt.
	- interrupts: interrupt specification for data-ready.

See Documentation/devicetree/bindings/net/can/bosch,m_can.yaml for additional
required property details.

Optional properties:
	- reset-gpios: Hardwired output GPIO. If not defined then software
		       reset.
	- device-state-gpios: Input GPIO that indicates if the device is in
			      a sleep state or if the device is active.
	- device-wake-gpios: Wake up GPIO to wake up the TCAN device.

Example:
tcan4x5x: tcan4x5x@0 {
		compatible = "ti,tcan4x5x";
		reg = <0>;
		#address-cells = <1>;
		#size-cells = <1>;
		spi-max-frequency = <10000000>;
		bosch,mram-cfg = <0x0 0 0 32 0 0 1 1>;
		interrupt-parent = <&gpio1>;
		interrupts = <14 IRQ_TYPE_LEVEL_LOW>;
		device-state-gpios = <&gpio3 21 GPIO_ACTIVE_HIGH>;
		device-wake-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH>;
		reset-gpios = <&gpio1 27 GPIO_ACTIVE_HIGH>;
};

Regards,
Jonathan

Hi Jonathan, 

Thanks, my customer had ported TCAN4550 to their platform. 

Any suggestion how to verify if your porting correct or not ? thanks!