TDA2P-ACD: Can interfaces swap in Linux

Mikhail Kolesov

Part Number: TDA2P-ACD

Hello,

I have a case when m_can and d_can change their Linux canX network interface number which leads to application SW UB. In most cases m_can starts as can0 network interface and d_can2 (in case of our board setup) as can1. But sometimes they are swapped (m_can goes to can1 and d_can2 goes to can0).

How to make a fixed setup between can controllers and there network interfaces representations ?

Using vision_sdk_3.07.

over 4 years ago

0 Keerthy J over 4 years ago

TI__Guru**** 169520 points

Hi,

Can you check if using alises in DT can help your issue:

https://stackoverflow.com/questions/17738709/dts-file-explanation-aliases

Best Regards,
Keerthy

+1 Mikhail Kolesov over 4 years ago

Prodigy 50 points

Hello,

Experiments with changing aliases do not change the naming of CAN interfaces, since can%d is fixed in can-dev SocketCAN kernel subsystem.
Resolved at our side by renaming to fixed (not known by can-dev/kernel) names using udev rule:

# make stable name for can network interfaces

# M_CAN controller
ACTION=="add", DEVPATH=="/devices/platform/44000000.ocp/42c01a00.mcan/net/can*", NAME="mcan0"

# D_CAN[2] controller
ACTION=="add", DEVPATH=="/devices/platform/44000000.ocp/48480000.can/net/can*", NAME="dcan2"

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TDA2P-ACD: Can interfaces swap in Linux