linux.git/include/linux/can, branch v6.18.21

can: dev: add can_get_ctrlmode_str()

2025-09-24T15:09:47+00:00

In an effort to give more human readable messages when errors occur
because of conflicting options, it can be useful to convert the CAN
control mode flags into text.

Add a function which converts the first set CAN control mode into a
human readable string. The reason to only convert the first one is to
simplify edge cases: imagine that there are several invalid control
modes, we would just return the first invalid one to the user, thus
not having to handle complex string concatenation. The user can then
solve the first problem, call the netlink interface again and see the
next issue.

People who wish to enumerate all the control modes can still do so by,
for example, using this new function in a for_each_set_bit() loop.

Signed-off-by: Vincent Mailhol 
Link: https://patch.msgid.link/20250923-canxl-netlink-prep-v4-19-e720d28f66fe@kernel.org
Signed-off-by: Marc Kleine-Budde

can: calc_bittiming: make can_calc_tdco() FD agnostic

2025-09-24T15:09:46+00:00

can_calc_tdco() uses the CAN_CTRLMODE_FD_TDC_MASK and
CAN_CTRLMODE_TDC_AUTO macros making it specific to CAN FD. Add the tdc
mask to the function parameter list. The value of the tdc auto flag
can then be derived from that mask and stored in a local variable.
This way, the function becomes CAN FD agnostic and can be reused later
on for the CAN XL TDC.

Signed-off-by: Vincent Mailhol 
Link: https://patch.msgid.link/20250923-canxl-netlink-prep-v4-18-e720d28f66fe@kernel.org
Signed-off-by: Marc Kleine-Budde

can: netlink: add can_validate_tdc()

2025-09-24T15:09:44+00:00

Factorise the TDC validation out of can_validate() and move it in the
new can_validate_tdc() function. This is a preparation patch for the
introduction of CAN XL because this TDC validation will be reused
later on.

Signed-off-by: Vincent Mailhol 
Link: https://patch.msgid.link/20250923-canxl-netlink-prep-v4-5-e720d28f66fe@kernel.org
Signed-off-by: Marc Kleine-Budde

can: dev: make can_get_relative_tdco() FD agnostic and move it to bittiming.h

2025-09-24T15:09:44+00:00

can_get_relative_tdco() needs to access can_priv->fd making it
specific to CAN FD. Change the function parameter from struct can_priv
to struct data_bittiming_params. This way, the function becomes CAN FD
agnostic and can be reused later on for the CAN XL TDC.

Now that we dropped the dependency on struct can_priv, also move
can_get_relative_tdco() back to bittiming.h where it was meant to
belong to.

Signed-off-by: Vincent Mailhol 
Link: https://patch.msgid.link/20250923-canxl-netlink-prep-v4-2-e720d28f66fe@kernel.org
Signed-off-by: Marc Kleine-Budde

can: dev: move struct data_bittiming_params to linux/can/bittiming.h

2025-09-24T15:09:43+00:00

In commit b803c4a4f788 ("can: dev: add struct data_bittiming_params to
group FD parameters"), struct data_bittiming_params was put into
linux/can/dev.h.

This structure being a collection of bittiming parameters, on second
thought, bittiming.h is actually a better location. This way, users of
struct data_bittiming_params will not have to forcefully include
linux/can/dev.h thus removing some complexity and reducing the risk of
circular dependencies in headers.

Move struct data_bittiming_params from linux/can/dev.h to
linux/can/bittiming.h.

Signed-off-by: Vincent Mailhol 
Link: https://patch.msgid.link/20250923-canxl-netlink-prep-v4-1-e720d28f66fe@kernel.org
Signed-off-by: Marc Kleine-Budde

can: populate the minimum and maximum MTU values

2025-09-24T15:04:22+00:00

By populating:

  net_device->min_mtu

and

  net_device->max_mtu

the net core infrastructure will automatically:

  1. validate that the user's inputs are in range.

  2. report those min and max MTU values through the netlink
     interface.

Add can_set_default_mtu() which sets the default mtu value as well as
the minimum and maximum values. The logic for the default mtu value
remains unchanged:

  - CANFD_MTU if the device has a static CAN_CTRLMODE_FD.

  - CAN_MTU otherwise.

Call can_set_default_mtu() each time the CAN_CTRLMODE_FD is modified.
This will guarantee that the MTU value is always consistent with the
control mode flags.

With this, the checks done in can_change_mtu() become fully redundant
and will be removed in an upcoming change and it is now possible to
confirm the minimum and maximum MTU values on a physical CAN interface
by doing:

  $ ip --details link show can0

The virtual interfaces (vcan and vxcan) are not impacted by this
change.

Signed-off-by: Vincent Mailhol 
Link: https://patch.msgid.link/20250923-can-fix-mtu-v3-3-581bde113f52@kernel.org
[mkl: squashed https://patch.msgid.link/20250924143644.17622-2-mailhol@kernel.org]
Signed-off-by: Marc Kleine-Budde

can: dev: turn can_set_static_ctrlmode() into a non-inline function

2025-09-23T08:04:58+00:00

can_set_static_ctrlmode() is declared as a static inline. But it is
only called in the probe function of the devices and so does not
really benefit from any kind of optimization.

Transform it into a "normal" function by moving it to

  drivers/net/can/dev/dev.c

Signed-off-by: Vincent Mailhol 
Link: https://patch.msgid.link/20250923-can-fix-mtu-v3-2-581bde113f52@kernel.org
Signed-off-by: Marc Kleine-Budde

can: peak: Modification of references to email accounts being deleted

2025-09-13T17:04:57+00:00

With the upcoming deletion of @peak-system.com accounts and following
the acquisition of PEAK-System and its brand by HMS-Networks, this fix
aims to migrate all address references to @hms-networks.com, as well
as to map my personal committer addresses to author addresses, while
taking the opportunity to correct the accent on the first ‘e’ of my
first name.

Signed-off-by: Stéphane Grosjean 
Link: https://patch.msgid.link/20250912081820.86314-1-stephane.grosjean@free.fr
Signed-off-by: Marc Kleine-Budde

can: bittiming: rename can_tdc_is_enabled() into can_fd_tdc_is_enabled()

2025-06-10T07:34:32+00:00

With the introduction of CAN XL, a new can_xl_tdc_is_enabled() helper
function will be introduced later on. Rename can_tdc_is_enabled() into
can_fd_tdc_is_enabled() to make it more explicit that this helper is
meant for CAN FD.

Signed-off-by: Vincent Mailhol 
Link: https://patch.msgid.link/20241112165118.586613-11-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde

can: bittiming: rename CAN_CTRLMODE_TDC_MASK into CAN_CTRLMODE_FD_TDC_MASK

2025-06-10T07:34:32+00:00

With the introduction of CAN XL, a new CAN_CTRLMODE_XL_TDC_MASK will
be introduced later on. Because CAN_CTRLMODE_TDC_MASK is not part of
the uapi, rename it to CAN_CTRLMODE_FD_TDC_MASK to make it more
explicit that this mask is meant for CAN FD.

Signed-off-by: Vincent Mailhol 
Link: https://patch.msgid.link/20241112165118.586613-10-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde