Commit Graph

200 Commits (dfca045cd4d0ea07ff4198ba392be3e718acaddc)

Author SHA1 Message Date
Oliver Hartkopp 166e87329c can: propagate CAN device capabilities via ml_priv
Commit 1a620a7238 ("can: raw: instantly reject unsupported CAN frames")
caused a sequence of dependency and linker fixes.

Instead of accessing CAN device internal data structures which caused the
dependency problems this patch introduces capability information into the
CAN specific ml_priv data which is accessible from both sides.

With this change the CAN network layer can check the required features and
the decoupling of the driver layer and network layer is restored.

Fixes: 1a620a7238 ("can: raw: instantly reject unsupported CAN frames")
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Vincent Mailhol <mailhol@kernel.org>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260109144135.8495-3-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2026-01-15 09:52:04 +01:00
Oliver Hartkopp 4650ff58a1 Revert "can: raw: instantly reject unsupported CAN frames"
This reverts commit 1a620a7238

and its follow-up fixes for the introduced dependency issues.

commit 1a620a7238 ("can: raw: instantly reject unsupported CAN frames")
commit cb2dc6d286 ("can: Kconfig: select CAN driver infrastructure by default")
commit 6abd4577bc ("can: fix build dependency")
commit 5a5aff6338 ("can: fix build dependency")

The entire problem was caused by the requirement that a new network layer
feature needed to know about the protocol capabilities of the CAN devices.
Instead of accessing CAN device internal data structures which caused the
dependency problems a better approach has been developed which makes use of
CAN specific ml_priv data which is accessible from both sides.

Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Vincent Mailhol <mailhol@kernel.org>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260109144135.8495-2-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2026-01-15 09:52:04 +01:00
Oliver Hartkopp cb2dc6d286 can: Kconfig: select CAN driver infrastructure by default
The CAN bus support enabled with CONFIG_CAN provides a socket-based
access to CAN interfaces. With the introduction of the latest CAN protocol
CAN XL additional configuration status information needs to be exposed to
the network layer than formerly provided by standard Linux network drivers.

This requires the CAN driver infrastructure to be selected by default.
As the CAN network layer can only operate on CAN interfaces anyway all
distributions and common default configs enable at least one CAN driver.

So selecting CONFIG_CAN_DEV when CONFIG_CAN is selected by the user has
no effect on established configurations but solves potential build issues
when CONFIG_CAN[_XXX]=y is set together with CANFIG_CAN_DEV=m

Fixes: 1a620a7238 ("can: raw: instantly reject unsupported CAN frames")
Reported-by: Vincent Mailhol <mailhol@kernel.org>
Closes: https://lore.kernel.org/all/CAMZ6RqL_nGszwoLPXn1Li8op-ox4k3Hs6p=Hw6+w0W=DTtobPw@mail.gmail.com/
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202511280531.YnWW2Rxc-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202511280842.djCQ0N0O-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202511282325.uVQFRTkA-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202511291520.guIE1QHj-lkp@intel.com/
Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20251129090500.17484-1-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-11-29 13:37:12 +01:00
Vincent Mailhol 9892339cf0 can: calc_bittiming: add PWM calculation
Perform the PWM calculation according to CiA recommendations.

Note that for databitrates greater than 5 MBPS, tqmin is less than
CAN_PWM_NS_MAX (which is defined to 200 nano seconds), consequently,
the result of the division:

  DIV_ROUND_UP(xl_ns, CAN_PWM_NS_MAX)

is one and thus the for loop automatically stops on the first
iteration giving a single PWM symbol per bit as expected. Because of
that, there is no actual need for a separate conditional branch for
when the databitrate is greater than 5 MBPS.

Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20251126-canxl-v8-10-e7e3eb74f889@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-11-26 11:20:43 +01:00
Vincent Mailhol 8e2a2885a2 can: bittiming: add PWM validation
Add can_validate_pwm() to validate the values pwms, pwml and pwml.
Error messages are added to each of the checks to inform the user on
what went wrong. Refer to those error messages to understand the
validation logic.

The boundary values CAN_PWM_DECODE_NS (the transceiver minimum
decoding margin) and CAN_PWM_NS_MAX (the maximum PWM symbol duration)
are hardcoded for the moment. Note that a transceiver capable of
bitrates higher than 20 Mbps may be able to handle a CAN_PWM_DECODE_NS
below 5 ns. If such transceivers become commercially available, this
code could be revisited to make this parameter configurable. For now,
leave it static.

Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20251126-canxl-v8-9-e7e3eb74f889@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-11-26 11:20:43 +01:00
Vincent Mailhol f6ccc2b293 can: bittiming: add PWM parameters
In CAN XL, higher data bit rates require the CAN transceiver to switch
its operation mode to use Pulse-Width Modulation (PWM) transmission
mode instead of the classic dominant/recessive transmission mode.

The PWM parameters are:

  - PWMS: pulse width modulation short phase
  - PWML: pulse width modulation long phase
  - PWMO: pulse width modulation offset

CiA 612-2 specifies PWMS and PWML to be at least 1 (arguably, PWML
shall be at least 2 to respect the PWMS < PWML rule). PWMO's minimum
is expected to always be zero. It is added more for consistency than
anything else.

Add struct can_pwm_const so that the different devices can provide
their minimum and maximum values.

When TMS is on, the runtime PWMS, PWML and PWMO are needed (either
calculated or provided by the user): add struct can_pwm to store
these.

TDC and PWM can not be used at the same time (TDC can only be used
when TMS is off and PWM only when TMS is on). struct can_pwm is thus
put together with struct can_tdc inside a union to save some space.

The netlink logic will be added in an upcoming change.

Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20251126-canxl-v8-8-e7e3eb74f889@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-11-26 11:20:43 +01:00
Oliver Hartkopp 6df01533e5 can: dev: can_dev_dropped_skb: drop CC/FD frames in CANXL-only mode
The error-signalling (ES) is a mandatory functionality for CAN CC and
CAN FD to report CAN frame format violations by sending an error-frame
signal on the bus.

A so-called 'mixed-mode' is intended to have (XL-tolerant) CAN FD nodes
and CAN XL nodes on one CAN segment, where the FD-controllers can talk
CC/FD and the XL-controllers can talk CC/FD/XL. This mixed-mode
utilizes the error-signalling for sending CC/FD/XL frames.

The CANXL-only mode disables the error-signalling in the CAN XL
controller. This mode does not allow CC/FD frames to be sent but
additionally offers a CAN XL transceiver mode switching (TMS).

Configured with CAN_CTRLMODE_FD and CAN_CTRLMODE_XL this leads to:

FD=0 XL=0 CC-only mode         (ES=1)
FD=1 XL=0 FD/CC mixed-mode     (ES=1)
FD=1 XL=1 XL/FD/CC mixed-mode  (ES=1)
FD=0 XL=1 XL-only mode         (ES=0, TMS optional)

The helper function can_dev_in_xl_only_mode() determines the required
value to disable error signalling in the CAN XL controller.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20251126-canxl-v8-7-e7e3eb74f889@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-11-26 11:20:43 +01:00
Vincent Mailhol e632816147 can: netlink: add initial CAN XL support
CAN XL uses bittiming parameters different from Classical CAN and CAN
FD. Thus, all the data bittiming parameters, including TDC, need to be
duplicated for CAN XL.

Add the CAN XL netlink interface for all the features which are common
with CAN FD. Any new CAN XL specific features are added later on.

The first time CAN XL is activated, the MTU is set by default to
CANXL_MAX_MTU. The user may then configure a custom MTU within the
CANXL_MIN_MTU to CANXL_MAX_MTU range, in which case, the custom MTU
value will be kept as long as CAN XL remains active.

Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20251126-canxl-v8-5-e7e3eb74f889@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-11-26 11:20:43 +01:00
Vincent Mailhol 60f511f443 can: netlink: add CAN_CTRLMODE_RESTRICTED
ISO 11898-1:2024 adds a new restricted operation mode. This mode is
added as a mandatory feature for nodes which support CAN XL and is
retrofitted as optional for legacy nodes (i.e. the ones which only
support Classical CAN and CAN FD).

The restricted operation mode is nearly the same as the listen only
mode: the node can not send data frames or remote frames and can not
send dominant bits if an error occurs. The only exception is that the
node shall still send the acknowledgment bit. A second niche exception
is that the node may still send a data frame containing a time
reference message if the node is a primary time provider, but because
the time provider feature is not yet implemented in the kernel, this
second exception is not relevant to us at the moment.

Add the CAN_CTRLMODE_RESTRICTED control mode flag and update the
can_dev_dropped_skb() helper function accordingly.

Finally, bail out if both CAN_CTRLMODE_LISTENONLY and
CAN_CTRLMODE_RESTRICTED are provided.

Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20251126-canxl-v8-4-e7e3eb74f889@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-11-26 11:20:43 +01:00
Vincent Mailhol d037d05c2e can: dev: can_dev_dropped_skb: drop CAN FD skbs if FD is off
Currently, the CAN FD skb validation logic is based on the MTU: the
interface is deemed FD capable if and only if its MTU is greater or
equal to CANFD_MTU.

This logic is showing its limit with the introduction of CAN XL. For
example, consider the two scenarios below:

  1. An interface configured with CAN FD on and CAN XL on

  2. An interface configured with CAN FD off and CAN XL on

In those two scenarios, the interfaces would have the same MTU:

  CANXL_MTU

making it impossible to differentiate which one has CAN FD turned on
and which one has it off.

Because of the limitation, the only non-UAPI-breaking workaround is to
do the check at the device level using the can_priv->ctrlmode flags.
Unfortunately, the virtual interfaces (vcan, vxcan), which do not have
a can_priv, are left behind.

Add a check on the CAN_CTRLMODE_FD flag in can_dev_dropped_skb() and
drop FD frames whenever the feature is turned off.

Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20251126-canxl-v8-3-e7e3eb74f889@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-11-26 11:20:43 +01:00
Vincent Mailhol 585a4f22c4 can: bittiming: apply NL_SET_ERR_MSG() to can_calc_bittiming()
When CONFIG_CAN_CALC_BITTIMING is disabled, the can_calc_bittiming()
functions can not be used and the user needs to provide all the
bittiming parameters.

Currently, can_calc_bittiming() prints an error message to the kernel
log. Instead use NL_SET_ERR_MSG() to make it return the error message
through the netlink interface so that the user can directly see it.

Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20251126-canxl-v8-2-e7e3eb74f889@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-11-26 11:20:43 +01:00
Vadim Fedorenko 4f6b0435c6 can: convert generic HW timestamp ioctl to ndo_hwtstamp callbacks
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>
2025-10-31 13:12:18 +01:00
Vincent Mailhol f968a24cad can: treewide: remove can_change_mtu()
can_change_mtu() became obsolete by commit 2304993860 ("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>
2025-10-17 09:57:13 +02:00
Vincent Mailhol 7de54546ff can: dev: add can_get_ctrlmode_str()
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 <mailhol@kernel.org>
Link: https://patch.msgid.link/20250923-canxl-netlink-prep-v4-19-e720d28f66fe@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-09-24 17:09:47 +02:00
Vincent Mailhol 6ffc1230d3 can: calc_bittiming: make can_calc_tdco() FD agnostic
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 <mailhol@kernel.org>
Link: https://patch.msgid.link/20250923-canxl-netlink-prep-v4-18-e720d28f66fe@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-09-24 17:09:46 +02:00
Vincent Mailhol b23a8425cb can: netlink: add can_validate_tdc()
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 <mailhol@kernel.org>
Link: https://patch.msgid.link/20250923-canxl-netlink-prep-v4-5-e720d28f66fe@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-09-24 17:09:44 +02:00
Vincent Mailhol 7208385df7 can: dev: make can_get_relative_tdco() FD agnostic and move it to bittiming.h
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 <mailhol@kernel.org>
Link: https://patch.msgid.link/20250923-canxl-netlink-prep-v4-2-e720d28f66fe@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-09-24 17:09:44 +02:00
Vincent Mailhol cc470fcf1d can: dev: move struct data_bittiming_params to linux/can/bittiming.h
In commit b803c4a4f7 ("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 <mailhol@kernel.org>
Link: https://patch.msgid.link/20250923-canxl-netlink-prep-v4-1-e720d28f66fe@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-09-24 17:09:43 +02:00
Vincent Mailhol 2304993860 can: populate the minimum and maximum MTU values
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 <mailhol@kernel.org>
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 <mkl@pengutronix.de>
2025-09-24 17:04:22 +02:00
Vincent Mailhol 7c7da8aa3f can: dev: turn can_set_static_ctrlmode() into a non-inline function
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 <mailhol@kernel.org>
Link: https://patch.msgid.link/20250923-can-fix-mtu-v3-2-581bde113f52@kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-09-23 10:04:58 +02:00
Stéphane Grosjean f1880f9cc1 can: peak: Modification of references to email accounts being deleted
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 <stephane.grosjean@hms-networks.com>
Link: https://patch.msgid.link/20250912081820.86314-1-stephane.grosjean@free.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-09-13 19:04:57 +02:00
Vincent Mailhol 23c0dc95bf can: bittiming: rename can_tdc_is_enabled() into can_fd_tdc_is_enabled()
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 <mailhol.vincent@wanadoo.fr>
Link: https://patch.msgid.link/20241112165118.586613-11-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-06-10 09:34:32 +02:00
Vincent Mailhol bee7e3322a can: bittiming: rename CAN_CTRLMODE_TDC_MASK into CAN_CTRLMODE_FD_TDC_MASK
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 <mailhol.vincent@wanadoo.fr>
Link: https://patch.msgid.link/20241112165118.586613-10-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-06-10 09:34:32 +02:00
Vincent Mailhol b803c4a4f7 can: dev: add struct data_bittiming_params to group FD parameters
This is a preparation patch for the introduction of CAN XL.

CAN FD and CAN XL uses similar bittiming parameters. Add one level of
nesting for all the CAN FD parameters. Typically:

  priv->can.data_bittiming;

becomes:

  priv->can.fd.data_bittiming;

This way, the CAN XL equivalent (to be introduced later) would be:

  priv->can.xl.data_bittiming;

Add the new struct data_bittiming_params which contains all the data
bittiming parameters, including the TDC and the callback functions.

This done, update all the CAN FD drivers to make use of the new
layout.

Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://patch.msgid.link/20250501171213.2161572-2-mailhol.vincent@wanadoo.fr
[mkl: fix rcar_canfd]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-05-21 14:33:28 +02:00
Kory Maincent 2111375b85 net: Add struct kernel_ethtool_ts_info
In prevision to add new UAPI for hwtstamp we will be limited to the struct
ethtool_ts_info that is currently passed in fixed binary format through the
ETHTOOL_GET_TS_INFO ethtool ioctl. It would be good if new kernel code
already started operating on an extensible kernel variant of that
structure, similar in concept to struct kernel_hwtstamp_config vs struct
hwtstamp_config.

Since struct ethtool_ts_info is in include/uapi/linux/ethtool.h, here
we introduce the kernel-only structure in include/linux/ethtool.h.
The manual copy is then made in the function called by ETHTOOL_GET_TS_INFO.

Acked-by: Shannon Nelson <shannon.nelson@amd.com>
Acked-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Link: https://patch.msgid.link/20240709-feature_ptp_netnext-v17-6-b5317f50df2a@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-07-15 08:02:26 -07:00
Marc Kleine-Budde 9beebc2b5d can: dev: add can_state_get_by_berr_counter() to return the CAN state based on the current error counters
Some CAN controllers do not have a register that contains the current
CAN state, but only a register that contains the error counters.

Introduce a new function can_state_get_by_berr_counter() that returns
the current TX and RX state depending on the provided CAN bit error
counters.

Link: https://lore.kernel.org/all/20231005-at91_can-rx_offload-v2-1-9987d53600e0@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-10-05 21:44:48 +02:00
Marc Kleine-Budde 8e0e2950c9 can: rx-offload: add can_rx_offload_get_echo_skb_queue_tail()
Add can_rx_offload_get_echo_skb_queue_tail(). This function addds the
echo skb at the end of rx-offload the queue. This is intended for
devices without timestamp support.

Link: https://lore.kernel.org/all/20230718-gs_usb-rx-offload-v2-2-716e542d14d5@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-07-28 09:45:25 +02:00
Marc Kleine-Budde 2e3df4a3b3 can: rx-offload: rename rx_offload_get_echo_skb() -> can_rx_offload_get_echo_skb_queue_timestamp()
Rename the rx_offload_get_echo_skb() function to
can_rx_offload_get_echo_skb_queue_timestamp(), since it inserts the
echo skb into the rx-offload queue sorted by timestamp.

This is a preparation for adding
can_rx_offload_get_echo_skb_queue_tail(), which adds the echo skb to
the end of the queue. This is intended for devices that do not support
timestamps.

Link: https://lore.kernel.org/all/20230718-gs_usb-rx-offload-v2-1-716e542d14d5@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-07-28 09:45:24 +02:00
Vincent Mailhol 80a2fbce45 can: length: refactor frame lengths definition to add size in bits
Introduce a method to calculate the exact size in bits of a CAN(-FD)
frame with or without dynamic bitstuffing.

These are all the possible combinations taken into account:

  - Classical CAN or CAN-FD
  - Standard or Extended frame format
  - CAN-FD CRC17 or CRC21
  - Include or not intermission

Instead of doing several individual macro definitions, declare the
can_frame_bits() function-like macro. To this extent, do a full
refactoring of the length definitions.

In addition add the can_frame_bytes(). This function-like macro
replaces the existing macro:

  - CAN_FRAME_OVERHEAD_SFF: can_frame_bytes(false, false, 0)
  - CAN_FRAME_OVERHEAD_EFF: can_frame_bytes(false, true, 0)
  - CANFD_FRAME_OVERHEAD_SFF: can_frame_bytes(true, false, 0)
  - CANFD_FRAME_OVERHEAD_EFF: can_frame_bytes(true, true, 0)

Function-like macros were chosen over inline functions because they
can be used to initialize const struct fields.

The different maximum frame lengths (maximum data length, including
intermission) are as follow:

   Frame type				bits	bytes
  -------------------------------------------------------
   Classic CAN SFF no bitstuffing	111	14
   Classic CAN EFF no bitstuffing	131	17
   Classic CAN SFF bitstuffing		135	17
   Classic CAN EFF bitstuffing		160	20
   CAN-FD SFF no bitstuffing		579	73
   CAN-FD EFF no bitstuffing		598	75
   CAN-FD SFF bitstuffing		712	89
   CAN-FD EFF bitstuffing		736	92

The macro CAN_FRAME_LEN_MAX and CANFD_FRAME_LEN_MAX are kept as an
alias to, respectively, can_frame_bytes(false, true, CAN_MAX_DLEN) and
can_frame_bytes(true, true, CANFD_MAX_DLEN).

In addition to the above:

 - Use ISO 11898-1:2015 definitions for the names of the CAN frame
   fields.
 - Include linux/bits.h for use of BITS_PER_BYTE.
 - Include linux/math.h for use of mult_frac() and
   DIV_ROUND_UP(). N.B: the use of DIV_ROUND_UP() is not new to this
   patch, but the include was previously omitted.
 - Add copyright 2023 for myself.

Suggested-by: Thomas Kopp <Thomas.Kopp@microchip.com>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Reviewed-by: Thomas Kopp <Thomas.Kopp@microchip.com>
Link: https://lore.kernel.org/all/20230611025728.450837-4-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-06-22 09:43:40 +02:00
Vincent Mailhol 10711b1110 can: length: fix description of the RRS field
The CAN-FD frames only have one reserved bit. The bit corresponding to
Classical CAN frame's RTR bit is called the "Remote Request
Substitution (RRS)" [1].

N.B. The RRS is not to be confused with the Substitute Remote Request
(SRR).

Fix the description in the CANFD_FRAME_OVERHEAD_SFF/EFF macros.

The total remains unchanged, so this is just a documentation fix.

In addition to the above add myself as copyright owner for 2020 (as
coauthor of the initial version, c.f. Fixes tag).

[1] ISO 11898-1:2015 paragraph 10.4.2.3 "Arbitration field":

  RSS bit [only in FD Frames]

    The RRS bit shall be transmitted in FD Frames at the position of
    the RTR bit in Classical Frames. The RRS bit shall be transmitted
    dominant, but receivers shall accept recessive and dominant RRS
    bits.

Fixes: 85d99c3e2a ("can: length: can_skb_get_frame_len(): introduce function to get data length of frame in data link layer")
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Reviewed-by: Thomas Kopp <Thomas.Kopp@microchip.com>
Link: https://lore.kernel.org/all/20230611025728.450837-3-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-06-22 09:43:39 +02:00
Vincent Mailhol 9fde4c557f can: length: fix bitstuffing count
The Stuff Bit Count is always coded on 4 bits [1]. Update the Stuff
Bit Count size accordingly.

In addition, the CRC fields of CAN FD Frames contain stuff bits at
fixed positions called fixed stuff bits [2]. The CRC field starts with
a fixed stuff bit and then has another fixed stuff bit after each
fourth bit [2], which allows us to derive this formula:

  FSB count = 1 + round_down(len(CRC field)/4)

The length of the CRC field is [1]:

  len(CRC field) = len(Stuff Bit Count) + len(CRC)
                 = 4 + len(CRC)

with len(CRC) either 17 or 21 bits depending of the payload length.

In conclusion, for CRC17:

  FSB count = 1 + round_down((4 + 17)/4)
            = 6

and for CRC 21:

  FSB count = 1 + round_down((4 + 21)/4)
            = 7

Add a Fixed Stuff bits (FSB) field with above values and update
CANFD_FRAME_OVERHEAD_SFF and CANFD_FRAME_OVERHEAD_EFF accordingly.

[1] ISO 11898-1:2015 section 10.4.2.6 "CRC field":

  The CRC field shall contain the CRC sequence followed by a recessive
  CRC delimiter. For FD Frames, the CRC field shall also contain the
  stuff count.

  Stuff count

  If FD Frames, the stuff count shall be at the beginning of the CRC
  field. It shall consist of the stuff bit count modulo 8 in a 3-bit
  gray code followed by a parity bit [...]

[2] ISO 11898-1:2015 paragraph 10.5 "Frame coding":

  In the CRC field of FD Frames, the stuff bits shall be inserted at
  fixed positions; they are called fixed stuff bits. There shall be a
  fixed stuff bit before the first bit of the stuff count, even if the
  last bits of the preceding field are a sequence of five consecutive
  bits of identical value, there shall be only the fixed stuff bit,
  there shall not be two consecutive stuff bits. A further fixed stuff
  bit shall be inserted after each fourth bit of the CRC field [...]

Fixes: 85d99c3e2a ("can: length: can_skb_get_frame_len(): introduce function to get data length of frame in data link layer")
Suggested-by: Thomas Kopp <Thomas.Kopp@microchip.com>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Reviewed-by: Thomas Kopp <Thomas.Kopp@microchip.com>
Link: https://lore.kernel.org/all/20230611025728.450837-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-06-22 09:43:39 +02:00
Marc Kleine-Budde 6882011e88 can: length: make header self contained
Include the headers that "can/length.h" depends on.

Fixes: bdd2e41319 ("can: dev: move length related code into seperate file")
Link: https://lore.kernel.org/all/20230509122854.350426-1-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-05-15 22:53:49 +02:00
Marc Kleine-Budde 65db3d8b52 can: bittiming: can_calc_bittiming(): add missing parameter to no-op function
In commit 286c0e09e8 ("can: bittiming: can_changelink() pass extack
down callstack") a new parameter was added to can_calc_bittiming(),
however the static inline no-op (which is used if
CONFIG_CAN_CALC_BITTIMING is disabled) wasn't converted.

Add the new parameter to the static inline no-op of
can_calc_bittiming().

Fixes: 286c0e09e8 ("can: bittiming: can_changelink() pass extack down callstack")
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/20230207201734.2905618-1-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-02-08 21:53:24 +01:00
Marc Kleine-Budde 5988bf737d can: bittiming: factor out can_sjw_set_default() and can_sjw_check()
Factor out the functionality of assigning a SJW default value into
can_sjw_set_default() and the checking the SJW limits into
can_sjw_check().

This functions will be improved and called from a different function
in the following patches.

Link: https://lore.kernel.org/all/20230202110854.2318594-11-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-02-06 13:57:26 +01:00
Marc Kleine-Budde 286c0e09e8 can: bittiming: can_changelink() pass extack down callstack
This is a preparation patch.

In order to pass warning/error messages during netlink calls back to
user space, pass the extack struct down the callstack of
can_changelink(), the actual error messages will be added in the
following ptaches.

Link: https://lore.kernel.org/all/20230202110854.2318594-10-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2023-02-06 13:57:26 +01:00
Heiko Schocher 26e8f6a752 can: sja1000: fix size of OCR_MODE_MASK define
bitfield mode in ocr register has only 2 bits not 3, so correct
the OCR_MODE_MASK define.

Signed-off-by: Heiko Schocher <hs@denx.de>
Link: https://lore.kernel.org/all/20221123071636.2407823-1-hs@denx.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-11-24 16:01:04 +01:00
Oliver Hartkopp ae64438be1 can: dev: fix skb drop check
In commit a6d190f8c7 ("can: skb: drop tx skb if in listen only
mode") the priv->ctrlmode element is read even on virtual CAN
interfaces that do not create the struct can_priv at startup. This
out-of-bounds read may lead to CAN frame drops for virtual CAN
interfaces like vcan and vxcan.

This patch mainly reverts the original commit and adds a new helper
for CAN interface drivers that provide the required information in
struct can_priv.

Fixes: a6d190f8c7 ("can: skb: drop tx skb if in listen only mode")
Reported-by: Dariusz Stojaczyk <Dariusz.Stojaczyk@opensynergy.com>
Cc: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Cc: Max Staudt <max@enpas.org>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/all/20221102095431.36831-1-socketcan@hartkopp.net
Cc: stable@vger.kernel.org # 6.0.x
[mkl: patch pch_can, too]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-11-07 14:00:27 +01:00
Oliver Hartkopp ebf87fc728 can: dev: add CAN XL support to virtual CAN
Make use of new can_skb_get_data_len() helper.
Add support for variable CANXL MTU using the new can_is_canxl_dev_mtu().

Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/all/20220912170725.120748-7-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-09-15 09:08:09 +02:00
Oliver Hartkopp fb08cba12b can: canxl: update CAN infrastructure for CAN XL frames
- add new ETH_P_CANXL ethernet protocol type
- update skb checks for CAN XL
- add alloc_canxl_skb() which now needs a data length parameter
- introduce init_can_skb_reserve() to reduce code duplication

Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/all/20220912170725.120748-6-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-09-15 09:08:09 +02:00
Oliver Hartkopp 467ef4c7b9 can: skb: add skb CAN frame data length helpers
Add two helpers to retrieve the data length from CAN sk_buffs and prepare
the length information to be a uint16 value for the CAN XL support.

Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/all/20220912170725.120748-3-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-09-15 09:08:08 +02:00
Oliver Hartkopp 96a7457a14 can: skb: unify skb CAN frame identification helpers
Replace open coded checks for sk_buffs containing Classical CAN and
CAN FD frame structures as a preparation for CAN XL support.

With the added length check the unintended processing of CAN XL frames
having the CANXL_XLF bit set can be suppressed even when the skb->len
fits to non CAN XL frames.

The CAN_RAW socket needs a rework to use these helpers. Therefore the
use of these helpers is postponed to the CAN_RAW CAN XL integration.

The J1939 protocol gets a check for Classical CAN frames too.

Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/all/20220912170725.120748-2-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-09-15 09:08:08 +02:00
Vincent Mailhol 90f942c5a6 can: dev: add generic function can_eth_ioctl_hwts()
Tools based on libpcap (such as tcpdump) expect the SIOCSHWTSTAMP
ioctl call to be supported. This is also specified in the kernel doc
[1]. The purpose of this ioctl is to toggle the hardware timestamps.

Currently, CAN devices which support hardware timestamping have those
always activated. can_eth_ioctl_hwts() is a dumb function that will
always succeed when requested to set tx_type to HWTSTAMP_TX_ON or
rx_filter to HWTSTAMP_FILTER_ALL.

[1] Kernel doc: Timestamping, section 3.1 "Hardware Timestamping
Implementation: Device Drivers"
Link: https://docs.kernel.org/networking/timestamping.html#hardware-timestamping-implementation-device-drivers

Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/all/20220727101641.198847-9-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-28 11:44:30 +02:00
Vincent Mailhol 7fb48d25b5 can: dev: add generic function can_ethtool_op_get_ts_info_hwts()
Add function can_ethtool_op_get_ts_info_hwts(). This function will be
used by CAN devices with hardware TX/RX timestamping support to
implement ethtool_ops::get_ts_info. This function does not offer
support to activate/deactivate hardware timestamps at device level nor
support the filter options (which is currently the case for all CAN
devices with hardware timestamping support).

The fact that hardware timestamp can not be deactivated at hardware
level does not impact the userland. As long as the user do not set
SO_TIMESTAMPING using a setsockopt() or ioctl(), the kernel will not
emit TX timestamps (RX timestamps will still be reproted as it is the
case currently).

Drivers which need more fine grained control remains free to implement
their own function, but we foresee that the generic function
introduced here will be sufficient for the majority.

Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/all/20220727101641.198847-8-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-28 11:44:30 +02:00
Dario Binacchi 036bff2800 can: netlink: dump bitrate 0 if can_priv::bittiming.bitrate is -1U
Upcoming changes on slcan driver will require you to specify a bitrate
of value -1 to prevent the open_candev() from failing but at the same
time highlighting that it is a fake value. In this case the command
`ip --details -s -s link show' would print 4294967295 as the bitrate
value. The patch change this value in 0.

Link: https://lore.kernel.org/all/20220628163137.413025-5-dario.binacchi@amarulasolutions.com
Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Tested-by: Jeroen Hofstee <jhofstee@victronenergy.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-07-03 11:34:24 +02:00
Vincent Mailhol ccd8a9351f can: skb: move can_dropped_invalid_skb() and can_skb_headroom_valid() to skb.c
The functions can_dropped_invalid_skb() and can_skb_headroom_valid()
grew a lot over the years to a point which it does not make much sense
to have them defined as static inline in header files. Move those two
functions to the .c counterpart of skb.h.

can_skb_headroom_valid()'s only caller being
can_dropped_invalid_skb(), the declaration is removed from the
header. Only can_dropped_invalid_skb() gets its symbol exported.

While doing so, do a small cleanup: add brackets around the else block
in can_dropped_invalid_skb().

Link: https://lore.kernel.org/all/20220610143009.323579-7-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Reported-by: kernel test robot <lkp@intel.com>
Acked-by: Max Staudt <max@enpas.org>
Tested-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-06-11 17:11:02 +02:00
Oliver Hartkopp 6c1e423a3c can: can-dev: remove obsolete CAN LED support
Since commit 30f3b42147 ("can: mark led trigger as broken") the
CAN specific LED support was disabled and marked as BROKEN. As the
common LED support with CONFIG_LEDS_TRIGGER_NETDEV should do this work
now the code can be removed as preparation for a CAN netdevice Kconfig
rework.

Link: https://lore.kernel.org/all/20220518154527.29046-1-socketcan@hartkopp.net
Suggested-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
[mkl: remove led.h from MAINTAINERS]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-05-19 22:15:51 +02:00
Marc Kleine-Budde eb38c2053b can: rx-offload: rename can_rx_offload_queue_sorted() -> can_rx_offload_queue_timestamp()
This patch renames the function can_rx_offload_queue_sorted() to
can_rx_offload_queue_timestamp(). This better describes what the
function does, it adds a newly RX'ed skb to the sorted queue by its
timestamp.

Link: https://lore.kernel.org/all/20220417194327.2699059-1-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-04-19 16:58:04 +02:00
Marc Kleine-Budde 5597f082fc can: bittiming: mark function arguments and local variables as const
This patch marks the arguments of some functions as well as some local
variables as constant.

Link: https://lore.kernel.org/all/20220124215642.3474154-7-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-02-24 08:26:03 +01:00
Vincent Mailhol 5fe1be81ef can: dev: reorder struct can_priv members for better packing
Save eight bytes of holes on x86-64 architectures by reordering the
members of struct can_priv.

Before:

| $ pahole -C can_priv drivers/net/can/dev/dev.o
| struct can_priv {
| 	struct net_device *        dev;                  /*     0     8 */
| 	struct can_device_stats    can_stats;            /*     8    24 */
| 	const struct can_bittiming_const  * bittiming_const; /*    32     8 */
| 	const struct can_bittiming_const  * data_bittiming_const; /*    40     8 */
| 	struct can_bittiming       bittiming;            /*    48    32 */
| 	/* --- cacheline 1 boundary (64 bytes) was 16 bytes ago --- */
| 	struct can_bittiming       data_bittiming;       /*    80    32 */
| 	const struct can_tdc_const  * tdc_const;         /*   112     8 */
| 	struct can_tdc             tdc;                  /*   120    12 */
| 	/* --- cacheline 2 boundary (128 bytes) was 4 bytes ago --- */
| 	unsigned int               bitrate_const_cnt;    /*   132     4 */
| 	const u32  *               bitrate_const;        /*   136     8 */
| 	const u32  *               data_bitrate_const;   /*   144     8 */
| 	unsigned int               data_bitrate_const_cnt; /*   152     4 */
| 	u32                        bitrate_max;          /*   156     4 */
| 	struct can_clock           clock;                /*   160     4 */
| 	unsigned int               termination_const_cnt; /*   164     4 */
| 	const u16  *               termination_const;    /*   168     8 */
| 	u16                        termination;          /*   176     2 */
|
| 	/* XXX 6 bytes hole, try to pack */
|
| 	struct gpio_desc *         termination_gpio;     /*   184     8 */
| 	/* --- cacheline 3 boundary (192 bytes) --- */
| 	u16                        termination_gpio_ohms[2]; /*   192     4 */
| 	enum can_state             state;                /*   196     4 */
| 	u32                        ctrlmode;             /*   200     4 */
| 	u32                        ctrlmode_supported;   /*   204     4 */
| 	int                        restart_ms;           /*   208     4 */
|
| 	/* XXX 4 bytes hole, try to pack */
|
| 	struct delayed_work        restart_work;         /*   216    88 */
|
| 	/* XXX last struct has 4 bytes of padding */
|
| 	/* --- cacheline 4 boundary (256 bytes) was 48 bytes ago --- */
| 	int                        (*do_set_bittiming)(struct net_device *); /*   304     8 */
| 	int                        (*do_set_data_bittiming)(struct net_device *); /*   312     8 */
| 	/* --- cacheline 5 boundary (320 bytes) --- */
| 	int                        (*do_set_mode)(struct net_device *, enum can_mode); /*   320     8 */
| 	int                        (*do_set_termination)(struct net_device *, u16); /*   328     8 */
| 	int                        (*do_get_state)(const struct net_device  *, enum can_state *); /*   336     8 */
| 	int                        (*do_get_berr_counter)(const struct net_device  *, struct can_berr_counter *); /*   344     8 */
| 	unsigned int               echo_skb_max;         /*   352     4 */
|
| 	/* XXX 4 bytes hole, try to pack */
|
| 	struct sk_buff * *         echo_skb;             /*   360     8 */
|
| 	/* size: 368, cachelines: 6, members: 32 */
| 	/* sum members: 354, holes: 3, sum holes: 14 */
| 	/* paddings: 1, sum paddings: 4 */
| 	/* last cacheline: 48 bytes */
| };

After:

| $ pahole -C can_priv drivers/net/can/dev/dev.o
| struct can_priv {
| 	struct net_device *        dev;                  /*     0     8 */
| 	struct can_device_stats    can_stats;            /*     8    24 */
| 	const struct can_bittiming_const  * bittiming_const; /*    32     8 */
| 	const struct can_bittiming_const  * data_bittiming_const; /*    40     8 */
| 	struct can_bittiming       bittiming;            /*    48    32 */
| 	/* --- cacheline 1 boundary (64 bytes) was 16 bytes ago --- */
| 	struct can_bittiming       data_bittiming;       /*    80    32 */
| 	const struct can_tdc_const  * tdc_const;         /*   112     8 */
| 	struct can_tdc             tdc;                  /*   120    12 */
| 	/* --- cacheline 2 boundary (128 bytes) was 4 bytes ago --- */
| 	unsigned int               bitrate_const_cnt;    /*   132     4 */
| 	const u32  *               bitrate_const;        /*   136     8 */
| 	const u32  *               data_bitrate_const;   /*   144     8 */
| 	unsigned int               data_bitrate_const_cnt; /*   152     4 */
| 	u32                        bitrate_max;          /*   156     4 */
| 	struct can_clock           clock;                /*   160     4 */
| 	unsigned int               termination_const_cnt; /*   164     4 */
| 	const u16  *               termination_const;    /*   168     8 */
| 	u16                        termination;          /*   176     2 */
|
| 	/* XXX 6 bytes hole, try to pack */
|
| 	struct gpio_desc *         termination_gpio;     /*   184     8 */
| 	/* --- cacheline 3 boundary (192 bytes) --- */
| 	u16                        termination_gpio_ohms[2]; /*   192     4 */
| 	unsigned int               echo_skb_max;         /*   196     4 */
| 	struct sk_buff * *         echo_skb;             /*   200     8 */
| 	enum can_state             state;                /*   208     4 */
| 	u32                        ctrlmode;             /*   212     4 */
| 	u32                        ctrlmode_supported;   /*   216     4 */
| 	int                        restart_ms;           /*   220     4 */
| 	struct delayed_work        restart_work;         /*   224    88 */
|
| 	/* XXX last struct has 4 bytes of padding */
|
| 	/* --- cacheline 4 boundary (256 bytes) was 56 bytes ago --- */
| 	int                        (*do_set_bittiming)(struct net_device *); /*   312     8 */
| 	/* --- cacheline 5 boundary (320 bytes) --- */
| 	int                        (*do_set_data_bittiming)(struct net_device *); /*   320     8 */
| 	int                        (*do_set_mode)(struct net_device *, enum can_mode); /*   328     8 */
| 	int                        (*do_set_termination)(struct net_device *, u16); /*   336     8 */
| 	int                        (*do_get_state)(const struct net_device  *, enum can_state *); /*   344     8 */
| 	int                        (*do_get_berr_counter)(const struct net_device  *, struct can_berr_counter *); /*   352     8 */
|
| 	/* size: 360, cachelines: 6, members: 32 */
| 	/* sum members: 354, holes: 1, sum holes: 6 */
| 	/* paddings: 1, sum paddings: 4 */
| 	/* last cacheline: 40 bytes */
| };

Link: https://lore.kernel.org/all/20211213160226.56219-4-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-01-05 12:09:06 +01:00
Vincent Mailhol 7d4a101c0b can: dev: add sanity check in can_set_static_ctrlmode()
Previous patch removed can_priv::ctrlmode_static to replace it with
can_get_static_ctrlmode().

A condition sine qua non for this to work is that the controller
static modes should never be set in can_priv::ctrlmode_supported
(c.f. the comment on can_priv::ctrlmode_supported which states that it
is for "options that can be *modified* by netlink"). Also, this
condition is already correctly fulfilled by all existing drivers
which rely on the ctrlmode_static feature.

Nonetheless, we added an extra safeguard in can_set_static_ctrlmode()
to return an error value and to warn the developer who would be
adventurous enough to set to static a given feature that is already
set to supported.

The drivers which rely on the static controller mode are then updated
to check the return value of can_set_static_ctrlmode().

Link: https://lore.kernel.org/all/20211213160226.56219-3-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-01-05 12:09:05 +01:00