Can has generic implementation of ndo_eth_ioctl which implements only HW
timestamping commands. Implement generic ndo_hwtstamp callbacks and use
it in drivers instead of generic ioctl interface.

Signed-off-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Reviewed-by: Kory Maincent <kory.maincent@bootlin.com>
Reviewed-by: Vincent Mailhol <mailhol@kernel.org>
Link: https://patch.msgid.link/20251029231620.1135640-2-vadim.fedorenko@linux.dev
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

can_change_mtu() became obsolete by commit 23049938605b ("can: populate the
minimum and maximum MTU values"). Now that net_device->min_mtu and
net_device->max_mtu are populated, all the checks are already done by
dev_validate_mtu() in net/core/dev.c.

Remove the net_device_ops->ndo_change_mtu() callback of all the physical
interfaces, then remove can_change_mtu(). Only keep the vcan_change_mtu()
and vxcan_change_mtu() because the virtual interfaces use their own
different MTU logic.

The only functional change this patch introduces is that now the user will
be able to change the MTU even if the interface is up. This does not matter
for Classical CAN and CAN FD because their MTU range is composed of only
one value, respectively CAN_MTU and CANFD_MTU. For the upcoming CAN XL, the
MTU will be configurable within the CANXL_MIN_MTU to CANXL_MAX_MTU range at
any time, even if the interface is up. This is consistent with the other
net protocols and does not contradict ISO 11898-1:2024 as having a
modifiable MTU is a kernel extension.

Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
Link: https://patch.msgid.link/20251003-remove-can_change_mtu-v1-1-337f8bc21181@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Register each CAN channel of the device as an devlink physical port.
This makes it easier to get device information for a given network
interface (i.e. can2).

Example output:
  $ devlink dev
  pci/0000:07:00.0
  pci/0000:08:00.0
  pci/0000:09:00.0

  $ devlink port
  pci/0000:07:00.0/0: type eth netdev can0 flavour physical port 0 splittable false
  pci/0000:07:00.0/1: type eth netdev can1 flavour physical port 1 splittable false
  pci/0000:07:00.0/2: type eth netdev can2 flavour physical port 2 splittable false
  pci/0000:07:00.0/3: type eth netdev can3 flavour physical port 3 splittable false
  pci/0000:08:00.0/0: type eth netdev can4 flavour physical port 0 splittable false
  pci/0000:08:00.0/1: type eth netdev can5 flavour physical port 1 splittable false
  pci/0000:09:00.0/0: type eth netdev can6 flavour physical port 0 splittable false
  pci/0000:09:00.0/1: type eth netdev can7 flavour physical port 1 splittable false
  pci/0000:09:00.0/2: type eth netdev can8 flavour physical port 2 splittable false
  pci/0000:09:00.0/3: type eth netdev can9 flavour physical port 3 splittable false

  $ devlink port show can2
  pci/0000:07:00.0/2: type eth netdev can2 flavour physical port 2 splittable false

  $ devlink dev info
  pci/0000:07:00.0:
    driver kvaser_pciefd
    versions:
        running:
          fw 1.3.75
  pci/0000:08:00.0:
    driver kvaser_pciefd
    versions:
        running:
          fw 2.4.29
  pci/0000:09:00.0:
    driver kvaser_pciefd
    versions:
        running:
          fw 1.3.72

  $  sudo ethtool -i can2
  driver: kvaser_pciefd
  version: 6.8.0-40-generic
  firmware-version: 1.3.75
  expansion-rom-version:
  bus-info: 0000:07:00.0
  supports-statistics: no
  supports-test: no
  supports-eeprom-access: no
  supports-register-dump: no
  supports-priv-flags: no

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Jimmy Assarsson <extja@kvaser.com>
Link: https://patch.msgid.link/20250725123230.8-10-extja@kvaser.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Expose device firmware version via devlink info_get().

Example output:
  $ devlink dev
  pci/0000:07:00.0
  pci/0000:08:00.0
  pci/0000:09:00.0

  $ devlink dev info
  pci/0000:07:00.0:
    driver kvaser_pciefd
    versions:
        running:
          fw 1.3.75
  pci/0000:08:00.0:
    driver kvaser_pciefd
    versions:
        running:
          fw 2.4.29
  pci/0000:09:00.0:
    driver kvaser_pciefd
    versions:
        running:
          fw 1.3.72

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Jimmy Assarsson <extja@kvaser.com>
Link: https://patch.msgid.link/20250725123230.8-9-extja@kvaser.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Add devlink support at device level.

Example output:
  $ devlink dev
  pci/0000:07:00.0
  pci/0000:08:00.0
  pci/0000:09:00.0

  $ devlink dev info
  pci/0000:07:00.0:
    driver kvaser_pciefd
  pci/0000:08:00.0:
    driver kvaser_pciefd
  pci/0000:09:00.0:
    driver kvaser_pciefd

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Jimmy Assarsson <extja@kvaser.com>
Link: https://patch.msgid.link/20250725123230.8-8-extja@kvaser.com
[mkl: kvaser_pciefd_remove(): fix use-after-free]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Split driver into C-file and header-file, to simplify future patches.
Move common definitions and declarations to a header file.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Jimmy Assarsson <extja@kvaser.com>
Link: https://patch.msgid.link/20250725123230.8-7-extja@kvaser.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>