The helper functions can_len2dlc and can_dlc2len are only relevant for
CAN FD data length code (DLC) conversion.
To fit the introduced can_cc_dlc2len for Classical CAN we rename:
can_dlc2len -> can_fd_dlc2len to get the payload length from the DLC
can_len2dlc -> can_fd_len2dlc to get the DLC from the payload length
Suggested-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201110101852.1973-6-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The naming of can_dlc as element of struct can_frame and also as variable
name is misleading as it claims to be a 'data length CODE' but in reality
it always was a plain data length.
With the indroduction of a new 'len' element in struct can_frame we can now
remove can_dlc as name and make clear which of the former uses was a plain
length (-> 'len') or a data length code (-> 'dlc') value.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201120100444.3199-1-socketcan@hartkopp.net
[mkl: gs_usb: keep struct gs_host_frame::can_dlc as is]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
netif_rx() is meant to be called from interrupt contexts. can_restart() may be
called by can_restart_work(), which is called from a worqueue, so it may run in
process context. Use netif_rx_ni() instead.
Fixes: 39549eef35 ("can: CAN Network device driver and Netlink interface")
Co-developed-by: Loris Fauster <loris.fauster@ttcontrol.com>
Signed-off-by: Loris Fauster <loris.fauster@ttcontrol.com>
Signed-off-by: Alejandro Concepcion Rodriguez <alejandro@acoro.eu>
Link: https://lore.kernel.org/r/4e84162b-fb31-3a73-fa9a-9438b4bd5234@acoro.eu
[mkl: use netif_rx_ni() instead of netif_rx_any_context()]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The can_get_echo_skb() function returns the number of received bytes to
be used for netdev statistics. In the case of RTR frames we get a valid
(potential non-zero) data length value which has to be passed for further
operations. But on the wire RTR frames have no payload length. Therefore
the value to be used in the statistics has to be zero for RTR frames.
Reported-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201020064443.80164-1-socketcan@hartkopp.net
Fixes: cf5046b309 ("can: dev: let can_get_echo_skb() return dlc of CAN frame")
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
If a driver calls can_get_echo_skb() during a hardware IRQ (which is often, but
not always, the case), the 'WARN_ON(in_irq)' in
net/core/skbuff.c#skb_release_head_state() might be triggered, under network
congestion circumstances, together with the potential risk of a NULL pointer
dereference.
The root cause of this issue is the call to kfree_skb() instead of
dev_kfree_skb_irq() in net/core/dev.c#enqueue_to_backlog().
This patch prevents the skb to be freed within the call to netif_rx() by
incrementing its reference count with skb_get(). The skb is finally freed by
one of the in-irq-context safe functions: dev_consume_skb_any() or
dev_kfree_skb_any(). The "any" version is used because some drivers might call
can_get_echo_skb() in a normal context.
The reason for this issue to occur is that initially, in the core network
stack, loopback skb were not supposed to be received in hardware IRQ context.
The CAN stack is an exeption.
This bug was previously reported back in 2017 in [1] but the proposed patch
never got accepted.
While [1] directly modifies net/core/dev.c, we try to propose here a
smoother modification local to CAN network stack (the assumption
behind is that only CAN devices are affected by this issue).
[1] http://lore.kernel.org/r/57a3ffb6-3309-3ad5-5a34-e93c3fe3614d@cetitec.com
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20201002154219.4887-2-mailhol.vincent@wanadoo.fr
Fixes: 39549eef35 ("can: CAN Network device driver and Netlink interface")
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Rename macro CAN_CALC_SYNC_SEG to CAN_SYNC_SEG and make it available
through include/linux/can/dev.h
Add an helper function can_bit_time() which returns the duration (in
time quanta) of one CAN bit.
Rationale for this patch: the sync segment and the bit time are two
concepts which are defined in the CAN ISO standard. Device drivers for
CAN might need those.
Please refer to ISO 11898-1:2015, section 11.3.1.1 "Bit time" for
additional information.
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20201002154219.4887-6-mailhol.vincent@wanadoo.fr
[mkl: Let can_bit_time() return an unsinged int, make argument const]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The function can_put_echo_skb() can fail for several reasons. It may
fail due to OOM, but when it fails it's usually due to locking problems
in the driver.
In order to help developing and debugging of new drivers propagate error
value in case of errors.
Link: https://lore.kernel.org/r/20200915223527.1417033-12-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Add missing attribute validation for IFLA_CAN_TERMINATION
to the netlink policy.
Fixes: 12a6075cab ("can: dev: add CAN interface termination API")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Value assigned to variable err is overwritten at line
562: err = priv->do_set_mode(dev, CAN_MODE_START); before
it can be used.
Also, notice that this code has been there since 2014.
Addresses-Coverity-ID: 1227031
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
of_node_put() needs to be called when the device node which is got
from of_get_child_by_name() finished using.
Fixes: 2290aefa2e ("can: dev: Add support for limiting configured bitrate")
Cc: Franklin S Cooper Jr <fcooper@ti.com>
Signed-off-by: Wen Yang <wenyang@linux.alibaba.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Merge tag 'linux-can-next-for-5.4-20190904' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next
Marc Kleine-Budde says:
====================
pull-request: can-next 2019-09-04 j1939
this is a pull request for net-next/master consisting of 21 patches.
the first 12 patches are by me and target the CAN core infrastructure.
They clean up the names of variables , structs and struct members,
convert can_rx_register() to use max() instead of open coding it and
remove unneeded code from the can_pernet_exit() callback.
The next three patches are also by me and they introduce and make use of
the CAN midlayer private structure. It is used to hold protocol specific
per device data structures.
The next patch is by Oleksij Rempel, switches the
&net->can.rcvlists_lock from a spin_lock() to a spin_lock_bh(), so that
it can be used from NAPI (soft IRQ) context.
The next 4 patches are by Kurt Van Dijck, he first updates his email
address via mailmap and then extends sockaddr_can to include j1939
members.
The final patch is the collective effort of many entities (The j1939
authors: Oliver Hartkopp, Bastian Stender, Elenita Hinds, kbuild test
robot, Kurt Van Dijck, Maxime Jayat, Robin van der Gracht, Oleksij
Rempel, Marc Kleine-Budde). It adds support of SAE J1939 protocol to the
CAN networking stack.
SAE J1939 is the vehicle bus recommended practice used for communication
and diagnostics among vehicle components. Originating in the car and
heavy-duty truck industry in the United States, it is now widely used in
other parts of the world.
P.S.: This pull request doesn't invalidate my last pull request:
"pull-request: can-next 2019-09-03".
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes the old method of allocating the per device protocol
specific memory via a netdevice_notifier. This had the drawback, that
the allocation can fail, leading to a lot of null pointer checks in the
code. This also makes the live cycle management of this memory quite
complicated.
This patch switches from the allocating the struct can_dev_rcv_lists in
a NETDEV_REGISTER call to using the dev->ml_priv, which is allocated by
the driver since the previous patch.
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch introduces the CAN midlayer private structure ("struct
can_ml_priv") which should be used to hold protocol specific per device
data structures. For now it's only member is "struct can_dev_rcv_lists".
The CAN midlayer private is allocated via alloc_netdev()'s private and
assigned to "struct net_device::ml_priv" during device creation. This is
done transparently for CAN drivers using alloc_candev(). The slcan, vcan
and vxcan drivers which are not using alloc_candev() have been adopted
manually. The memory layout of the netdev_priv allocated via
alloc_candev() will looke like this:
+-------------------------+
| driver's priv |
+-------------------------+
| struct can_ml_priv |
+-------------------------+
| array of struct sk_buff |
+-------------------------+
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
CONFIG_CAN_LEDS is deprecated. When trying to use the generic netdev
trigger as suggested, there's a small inconsistency with the link
property: The LED is on initially, stays on when the device is brought
up, and then turns off (as expected) when the device is brought down.
Make sure the LED always reflects the state of the CAN device.
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the version 2 of the gnu general public
license as published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not see http www gnu org
licenses
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 15 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000437.427740574@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch revert commit 7da11ba5c5
("can: dev: __can_get_echo_skb(): print error message, if trying to echo non existing skb")
After introduction of this change we encountered following new error
message on various i.MX plattforms (flexcan):
| flexcan 53fc8000.can can0: __can_get_echo_skb: BUG! Trying to echo non
| existing skb: can_priv::echo_skb[0]
The introduction of the message was a mistake because
priv->echo_skb[idx] = NULL is a perfectly valid in following case: If
CAN_RAW_LOOPBACK is disabled (setsockopt) in applications, the pkt_type
of the tx skb's given to can_put_echo_skb is set to PACKET_LOOPBACK. In
this case can_put_echo_skb will not set priv->echo_skb[idx]. It is
therefore kept NULL.
As additional argument for revert: The order of check and usage of idx
was changed. idx is used to access an array element before checking it's
boundaries.
Signed-off-by: Manfred Schlaegl <manfred.schlaegl@ginzinger.com>
Fixes: 7da11ba5c5 ("can: dev: __can_get_echo_skb(): print error message, if trying to echo non existing skb")
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Prior to echoing a successfully transmitted CAN frame (by calling
can_get_echo_skb()), CAN drivers have to put the CAN frame (by calling
can_put_echo_skb() in the transmit function). These put and get function
take an index as parameter, which is used to identify the CAN frame.
A driver calling can_get_echo_skb() with a index not pointing to a skb
is a BUG, so add an appropriate error message.
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
If the "struct can_priv::echo_skb" is accessed out of bounds would lead
to a kernel crash. Better print a sensible warning message instead and
try to recover.
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch replaces the use of "struct can_frame::can_dlc" by "struct
canfd_frame::len" to access the frame's length. As it is ensured that
both structures have a compatible memory layout for this member this is
no functional change. Futher, this compatibility is documented in a
comment.
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch factors out all non sending parts of can_get_echo_skb() into
a seperate function __can_get_echo_skb(), so that it can be re-used in
an upcoming patch.
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The existing SocketCAN implementation provides alloc_candev() to
allocate a CAN device using a single Tx and Rx queue. This can lead to
priority inversion in case the single Tx queue is already full with low
priority messages and a high priority message needs to be sent while the
bus is fully loaded with medium priority messages.
This problem can be solved by using the existing multi-queue support of
the network subsytem. The commit makes it possible to use multi-queue in
the CAN subsystem in the same way it is used in the Ethernet subsystem
by adding an alloc_candev_mqs() call and accompanying macros. With this
support a CAN device can use multi-queue qdisc (e.g. mqprio) to avoid
the aforementioned priority inversion.
The exisiting functionality of alloc_candev() is the same as before.
CAN devices need to have prioritized multiple hardware queues or are
able to abort waiting for arbitration to make sensible use of
multi-queues.
Signed-off-by: Zhu Yi <yi.zhu5@cn.bosch.com>
Signed-off-by: Mark Jonas <mark.jonas@de.bosch.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
use helper skb_put_zero to replace the pattern of skb_put() && memset()
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
bus-off is usually caused by hardware malfunction or configuration error
(baud rate mismatch) and causes a complete loss of communication.
Increase the "bus-off" message's severity from netdev_dbg() to
netdev_info() to make it visible to the user.
A can interface going into bus-off is similar in severity to ethernet's
"Link is Down" message, which is also printed at info level.
It is debatable whether the the "restarted" message should also be
changed to netdev_info() to make the interface state changes
comprehensible from the kernel log. I have chosen to keep the
"restarted" message at dbg for now as the "bus-off" message should be
enough for the user to notice and investigate the problem.
Signed-off-by: Jakob Unterwurzacher <jakob.unterwurzacher@theobroma-systems.com>
Cc: linux-can@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The kernel documentation is now restructured text. Convert the SocketCAN
documentation and include it in the toplevel kernel documentation.
This patch doesn't do any content change.
All references to can.txt in the code are converted to can.rst.
Signed-off-by: Robert Schwebel <r.schwebel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Various CAN or CAN-FD IP may be able to run at a faster rate than
what the transceiver the CAN node is connected to. This can lead to
unexpected errors. However, CAN transceivers typically have fixed
limitations and provide no means to discover these limitations at
runtime. Therefore, add support for a can-transceiver node that
can be reused by other CAN peripheral drivers to determine for both
CAN and CAN-FD what the max bitrate that can be used. If the user
tries to configure CAN to pass these maximum bitrates it will throw
an error.
Also add support for reading bitrate_max via the netlink interface.
Reviewed-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com>
[nsekhar@ti.com: fix build error with !CONFIG_OF]
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Add support for extended error reporting.
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for extended error reporting.
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for extended error reporting.
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.
Make these functions (skb_put, __skb_put and pskb_put) return void *
and remove all the casts across the tree, adding a (u8 *) cast only
where the unsigned char pointer was used directly, all done with the
following spatch:
@@
expression SKB, LEN;
typedef u8;
identifier fn = { skb_put, __skb_put };
@@
- *(fn(SKB, LEN))
+ *(u8 *)fn(SKB, LEN)
@@
expression E, SKB, LEN;
identifier fn = { skb_put, __skb_put };
type T;
@@
- E = ((T *)(fn(SKB, LEN)))
+ E = fn(SKB, LEN)
which actually doesn't cover pskb_put since there are only three
users overall.
A handful of stragglers were converted manually, notably a macro in
drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many
instances in net/bluetooth/hci_sock.c. In the former file, I also
had to fix one whitespace problem spatch introduced.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In OOM situations where no skb can be allocated, can_change_state() may
be called with cf == NULL. As this function updates the state and error
statistics it's not an option to skip the call to can_change_state() in
OOM situations.
This patch makes can_change_state() robust, so that it can be called
with cf == NULL.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Some CAN interfaces only support fixed fixed bitrates. This patch adds a
netlink interface to get the list of the CAN interface's fixed bitrates and
data bitrates.
Inside the driver arrays of supported data- bitrate values are defined.
const u32 drvname_bitrate[] = { 20000, 50000, 100000 };
const u32 drvname_data_bitrate[] = { 200000, 500000, 1000000 };
struct drvname_priv *priv;
priv = netdev_priv(dev);
priv->bitrate_const = drvname_bitrate;
priv->bitrate_const_cnt = ARRAY_SIZE(drvname_bitrate);
priv->data_bitrate_const = drvname_data_bitrate;
priv->data_bitrate_const_cnt = ARRAY_SIZE(drvname_data_bitrate);
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Until commit
08da7da41e can: provide a separate bittiming_const parameter to
bittiming functions
it was possible to have devices not providing bittiming_const. This can
be used for hardware that only support pre-defined fixed bitrates.
Although no mainline driver is using this feature so far.
This patch re-introduces this feature for the bitrate and the data
bitrate (of CANFD controllers). The driver can specify the
{data_,}bittiming_const (if the bittiming parameters should be
calculated from the bittiming_const) as before or no
{data_,}bittiming_const but implement the do_set_{data,}bittiming
callback.
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch adds a netlink interface to configure the CAN bus termination of
CAN interfaces.
Inside the driver an array of supported termination values is defined:
const u16 drvname_termination[] = { 60, 120, CAN_TERMINATION_DISABLED };
struct drvname_priv *priv;
priv = netdev_priv(dev);
priv->termination_const = drvname_termination;
priv->termination_const_cnt = ARRAY_SIZE(drvname_termination);
priv->termination = CAN_TERMINATION_DISABLED;
And the funtion to set the value has to be defined:
priv->do_set_termination = drvname_set_termination;
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Reviewed-by: Ramesh Shanmugasundaram <Ramesh.shanmugasundaram@bp.renesas.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
A timer was used to restart after the bus-off state, leading to a
relatively large can_restart() executed in an interrupt context,
which in turn sets up pinctrl. When this happens during system boot,
there is a high probability of grabbing the pinctrl_list_mutex,
which is locked already by the probe() of other device, making the
kernel suspect a deadlock condition [1].
To resolve this issue, the restart_timer is replaced by a delayed
work.
[1] https://github.com/victronenergy/venus/issues/24
Signed-off-by: Sergei Miroshnichenko <sergeimir@emcraft.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Several cases of overlapping changes, except the packet scheduler
conflicts which deal with the addition of the free list parameter
to qdisc_enqueue().
Signed-off-by: David S. Miller <davem@davemloft.net>
For 'real' hardware CAN devices the netlink interface is used to set CAN
specific communication parameters. Real CAN hardware can not be created nor
removed with the ip tool ...
This patch adds a private dellink function for the CAN device driver interface
that does just nothing.
It's a follow up to commit 993e6f2fd ("can: fix oops caused by wrong rtnl
newlink usage") but for dellink.
Reported-by: ajneu <ajneu1@gmail.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
With upstream commit bb208f144c (can: fix handling of unmodifiable
configuration options) a new can_validate() function was introduced.
When invoking 'ip link set can0 type can' without any configuration data
can_validate() tries to validate the content without taking into account that
there's totally no content. This patch adds a check for missing content.
Reported-by: ajneu <ajneu1@gmail.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch optimizes the calculation of the sample point. To understand what it
does have a look at the original implementation.
If there is a combination of timing parameters where both the bitrate and
sample point error are 0 the current implementation will find it.
However if the reference clock doesn't allow an optimal bitrate (this means the
bitrate error is always != 0) there might be several timing parameter
combinations having the same bitrate error. The original implementation will
allways choose the one with the highest brp. The actual sample point error
isn't taken into account.
This patch changes the algorithm to minimize the sample point error, too. Now a
brp/tseg combination is accepted as better if one of these condition are
fulfilled:
1) the bit rate error must be smaller, or
2) the bit rate error must be equal and
the sample point error must be equal or smaller
If a smaller bit rate error is found the sample point error is reset. This
ensures that we first optimize for small bit rate error and then for small
sample point errors.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
As described in 'can: m_can: tag current CAN FD controllers as non-ISO'
(6cfda7fbeb) it is possible to define fixed configuration options by
setting the according bit in 'ctrlmode' and clear it in 'ctrlmode_supported'.
This leads to the incovenience that the fixed configuration bits can not be
passed by netlink even when they have the correct values (e.g. non-ISO, FD).
This patch fixes that issue and not only allows fixed set bit values to be set
again but now requires(!) to provide these fixed values at configuration time.
A valid CAN FD configuration consists of a nominal/arbitration bittiming, a
data bittiming and a control mode with CAN_CTRLMODE_FD set - which is now
enforced by a new can_validate() function. This fix additionally removed the
inconsistency that was prohibiting the support of 'CANFD-only' controller
drivers, like the RCar CAN FD.
For this reason a new helper can_set_static_ctrlmode() has been introduced to
provide a proper interface to handle static enabled CAN controller options.
Reported-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Reviewed-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Cc: <stable@vger.kernel.org> # >= 3.18
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The sizeof() is invoked on an incorrect variable, likely due to some
copy-paste error, and this might result in memory corruption. Fix this.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: netdev@vger.kernel.org
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Oliver Hartkopp