Starting the CAN device on DK2 Board

[Niklas Voi]

Hi,

i created a DT in Cubemx and now everythings works fine, with the exception of the CAN Bus.

Here are the Snippets of the Device in DT:

/// Clocks section
CLK_FDCAN_PLL4R in the Clocks Section
///
&m_can1{
	pinctrl-names = "default", "sleep";
	pinctrl-0 = <&fdcan1_pins_mx>;
	pinctrl-1 = <&fdcan1_sleep_pins_mx>;
	status = "okay";
 
	/* USER CODE BEGIN m_can1 */
	/* USER CODE END m_can1 */
};
 

And here are some debugs things from the Console:

root@stm32mp1~# ip link set can0 type can bitrate 125000
root@stm32mp1:~# ip link set can0 up
[ 2704.826934] IPv6: ADDRCONF(NETDEV_UP): can0: link is not ready
[ 2704.831483] IPv6: ADDRCONF(NETDEV_CHANGE): can0: link becomes ready
root@stm32mp1:~# cansend can0 1337#34.23.44 
interface = can0, family = 29, type = 3, proto = 1
[ 2720.472282] m_can 4400e000.can can0: bus-off
root@stm32mp1:~# 

I connected a scope FDCAN_RX / TX. I also have a complete Transceiver on a PCB connected to this device, with a termination.

Is there any hint, why the device is getting in bus-off?

[Olivier GALLIEN]

Hi @Niklas Voi​ 

Be careful that Device Tree generated by CubeMX may require some customization inside USER_CODE tags in order to complete configuration.

I recommanded you to go through https://wiki.st.com/stm32mpu/wiki/CAN_overview and related https://wiki.st.com/stm32mpu/wiki/FDCAN_device_tree_configuration in order to check this.

Hope it help

Olivier