On 27.10.2021 03:05:53, Vincent Mailhol wrote:

The field dev_port of struct net_device indicates the port number of a
network device [1]. This patch populates this field.

This field can be helpful to distinguish between the two network
interfaces of a dual channel device (i.e. ES581.4 or ES582.1). Indeed,
at the moment, all the network interfaces of a same device share the
same static udev attributes c.f. output of:

| udevadm info --attribute-walk /sys/class/net/canX

The dev_port attribute can then be used to write some udev rules to,
for example, assign a permanent name to each network interface based
on the serial/dev_port pair (which is convenient when you have a test
bench with several CAN devices connected simultaneously and wish to
keep consistent interface names upon reboot).

[1] https://www.kernel.org/doc/Documentation/ABI/testing/sysfs-class-net

Suggested-by: Lukas Magel <redacted>
Signed-off-by: Vincent Mailhol <redacted>

Applied to linux-can-next/testing.

Thanks,
Marc

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