Add a dedicated flag in uapi/linux/can/error.h to notify the userland
that fields data[6] and data[7] of the CAN error frame were
respectively populated with the tx and rx error counters.
For all driver tree-wide, set up this flags whenever needed.
Link: https://lore.kernel.org/all/20220719143550.3681-12-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
During bus off, the error count is greater than 255 and can not fit in
a u8.
Fixes: 0024d8ad16 ("can: usb_8dev: Add support for USB2CAN interface from 8 devices")
Link: https://lore.kernel.org/all/20220719143550.3681-10-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
During bus off, the error count is greater than 255 and can not fit in
a u8.
Fixes: 7259124eac ("can: kvaser_usb: Split driver into kvaser_usb_core.c and kvaser_usb_leaf.c")
Link: https://lore.kernel.org/all/20220719143550.3681-9-mailhol.vincent@wanadoo.fr
CC: Jimmy Assarsson <extja@kvaser.com>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
During bus off, the error count is greater than 255 and can not fit in
a u8.
Fixes: aec5fb2268 ("can: kvaser_usb: Add support for Kvaser USB hydra family")
Link: https://lore.kernel.org/all/20220719143550.3681-8-mailhol.vincent@wanadoo.fr
CC: Jimmy Assarsson <extja@kvaser.com>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
During bus off, the error count is greater than 255 and can not fit in
a u8.
Fixes: 0738eff14d ("can: Allwinner A10/A20 CAN Controller support - Kernel module")
Link: https://lore.kernel.org/all/20220719143550.3681-7-mailhol.vincent@wanadoo.fr
CC: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
During bus off, the error count is greater than 255 and can not fit in
a u8.
Fixes: 215db1856e ("can: sja1000: Consolidate and unify state change handling")
Link: https://lore.kernel.org/all/20220719143550.3681-4-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
During bus off, the error count is greater than 255 and can not fit in
a u8.
Fixes: 0c78ab76a0 ("pch_can: Add setting TEC/REC statistics processing")
Link: https://lore.kernel.org/all/20220719143550.3681-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The CANFD-USB PCAN-USB FD interface undergoes an internal component
change that requires a slight modification of its drivers, which leads
them to dynamically use endpoint numbers provided by the interface
itself. In addition to a change in the calls to the USB functions
exported by the kernel, the detection of the USB interface dedicated
to CAN must also be modified, as some PEAK-System devices support
other interfaces than CAN.
Link: https://lore.kernel.org/all/20220719120632.26774-3-s.grosjean@peak-system.com
Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
[mkl: add missing cpu_to_le16() conversion]
[mkl: fix networking block comment style]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The data structure returned from the USB device contains a number
flashed by the user and not the serial number of the device.
Link: https://lore.kernel.org/all/20220719120632.26774-2-s.grosjean@peak-system.com
Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Mark the input prompt and data pointer as const.
Link: https://lore.kernel.org/all/20220719120632.26774-1-s.grosjean@peak-system.com
Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
[mkl: mark data pointer as const, too; update commit message]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The update is compatible/pure extension of 2.x IP core version
- new option for 2, 4, or 8 Tx buffers option during synthesis.
The 2.x version has fixed 4 Tx buffers. 3.x version default
is 4 as well
- new REG_TX_COMMAND_TXT_BUFFER_COUNT provides synthesis
choice. When read as 0 assume 2.x core with fixed 4 Tx buffers.
- new REG_ERR_CAPT_TS_BITS field to provide most significant
active/implemented timestamp bit. For 2.x read as zero,
assume value 63 is such case for 64 bit counter.
- new REG_MODE_RXBAM bit which controls automatic advance
to next word after Rx FIFO register read. Bit is set
to 1 by default after the core reset (REG_MODE_RST)
and value 1 has to be preserved for the normal ctucanfd
Linux driver operation. Even preceding driver version
resets core and then modifies only known/required MODE
register bits so backward and forward compatibility is
ensured.
See complete datasheet for time-triggered and other
updated capabilities
http://canbus.pages.fel.cvut.cz/ctucanfd_ip_core/doc/Datasheet.pdf
The fields related to ongoing Ondrej Ille's work
on fault tolerant version with parity protected buffers
and FIFOs are not included for now. Their inclusion will
be considered when design is settled and tested.
Link: https://lore.kernel.org/all/14a98ed1829121f0f3bde784f1aa533bc3cc7fe0.1658139843.git.pisa@cmp.felk.cvut.cz
Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
As per Chapter 6.5.16 of the RZ/N1 Peripheral Manual, The SJA1000
CAN controller does not support Clock Divider Register compared to
the reference Philips SJA1000 device.
This patch adds a device quirk to handle this difference.
Link: https://lore.kernel.org/all/20220710115248.190280-4-biju.das.jz@bp.renesas.com
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The snprintf() function returns the number of bytes which *would* have
been copied if there were no space. So, since this code does not check
the return value, there if the buffer was not large enough then there
would be a buffer overflow two lines later when it does:
actual = sl->tty->ops->write(sl->tty, sl->xbuff, n);
Use scnprintf() instead because that returns the number of bytes which
were actually copied.
Fixes: 52f9ac85b8 ("can: slcan: allow to send commands to the adapter")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/all/YsVA9KoY/ZSvNGYk@kili
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In mcp251xfd_register_get_dev_id() the device ID register is read with
handcrafted SPI transfers. As all registers, this register is in
little endian. Further it is not naturally aligned in struct
mcp251xfd_map_buf_nocrc::data. However after the transfer the register
content is converted from big endian to CPU endianness not taking care
of being unaligned.
Fix the conversion by converting from little endian to CPU endianness
taking the unaligned source into account.
Side note: So far the register content is 0x0 on all mcp251xfd
compatible chips, and is only used for an informative printk.
Link: https://lore.kernel.org/all/20220627092859.809042-1-mkl@pengutronix.de
Fixes: 55e5b97f00 ("can: mcp25xxfd: add driver for Microchip MCP25xxFD SPI CAN")
Reviewed-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The device ID register is 32 bits wide. The driver uses incorrectly
the size of a pointer to a u32 to calculate the length of the SPI
transfer. This results in a read of 2 registers on 64 bit platforms.
This is no problem on the Linux side, as the RX buffer of the SPI
transfer is large enough. In the mpc251xfd chip this results in the
read of an undocumented register. So far no problems were observed.
Fix the length of the SPI transfer to read the device ID register
only.
Link: https://lore.kernel.org/all/20220616094914.244440-1-mkl@pengutronix.de
Fixes: 55e5b97f00 ("can: mcp25xxfd: add driver for Microchip MCP25xxFD SPI CAN")
Reported-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In commit 169d00a256 ("can: mcp251xfd: add TX IRQ coalescing
support") software based TX coalescing was added to the driver. The
key idea is to keep the TX complete IRQ disabled for some time after
processing it and re-enable later by a hrtimer. When bringing the
interface down, this timer has to be stopped.
Add the missing hrtimer_cancel() of the tx_irq_time hrtimer to
mcp251xfd_stop().
Link: https://lore.kernel.org/all/20220620143942.891811-1-mkl@pengutronix.de
Fixes: 169d00a256 ("can: mcp251xfd: add TX IRQ coalescing support")
Cc: stable@vger.kernel.org # v5.18
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The mcp251xfd compatible chips have an erratum ([1], [2]), where the
received CRC doesn't match the calculated CRC. In commit
c7eb923c3c ("can: mcp251xfd: mcp251xfd_regmap_crc_read(): work
around broken CRC on TBC register") the following workaround was
implementierend.
- If a CRC read error on the TBC register is detected and the first
byte is 0x00 or 0x80, the most significant bit of the first byte is
flipped and the CRC is calculated again.
- If the CRC now matches, the _original_ data is passed to the reader.
For now we assume transferred data was OK.
New investigations and simulations indicate that the CRC send by the
device is calculated on correct data, and the data is incorrectly
received by the SPI host controller.
Use flipped instead of original data and update workaround description
in mcp251xfd_regmap_crc_read().
[1] mcp2517fd: DS80000792C: "Incorrect CRC for certain READ_CRC commands"
[2] mcp2518fd: DS80000789C: "Incorrect CRC for certain READ_CRC commands"
Link: https://lore.kernel.org/all/DM4PR11MB53901D49578FE265B239E55AFB7C9@DM4PR11MB5390.namprd11.prod.outlook.com
Fixes: c7eb923c3c ("can: mcp251xfd: mcp251xfd_regmap_crc_read(): work around broken CRC on TBC register")
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Kopp <thomas.kopp@microchip.com>
[mkl: split into 2 patches, update patch description and documentation]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The mcp251xfd compatible chips have an erratum ([1], [2]), where the
received CRC doesn't match the calculated CRC. In commit
c7eb923c3c ("can: mcp251xfd: mcp251xfd_regmap_crc_read(): work
around broken CRC on TBC register") the following workaround was
implementierend.
- If a CRC read error on the TBC register is detected and the first
byte is 0x00 or 0x80, the most significant bit of the first byte is
flipped and the CRC is calculated again.
- If the CRC now matches, the _original_ data is passed to the reader.
For now we assume transferred data was OK.
Measurements on the mcp2517fd show that the workaround is applicable
not only of the lowest byte is 0x00 or 0x80, but also if 3 least
significant bits are set.
Update check on 1st data byte and workaround description accordingly.
[1] mcp2517fd: DS80000792C: "Incorrect CRC for certain READ_CRC commands"
[2] mcp2518fd: DS80000789C: "Incorrect CRC for certain READ_CRC commands"
Link: https://lore.kernel.org/all/DM4PR11MB53901D49578FE265B239E55AFB7C9@DM4PR11MB5390.namprd11.prod.outlook.com
Fixes: c7eb923c3c ("can: mcp251xfd: mcp251xfd_regmap_crc_read(): work around broken CRC on TBC register")
Cc: stable@vger.kernel.org
Reported-by: Pavel Modilaynen <pavel.modilaynen@volvocars.com>
Signed-off-by: Thomas Kopp <thomas.kopp@microchip.com>
[mkl: split into 2 patches, update patch description and documentation]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Use correct bittiming limits depending on device. For devices based on
USBcanII, Leaf M32C or Leaf i.MX28.
Fixes: 080f40a6fa ("can: kvaser_usb: Add support for Kvaser CAN/USB devices")
Fixes: b4f20130af ("can: kvaser_usb: add support for Kvaser Leaf v2 and usb mini PCIe")
Fixes: f5d4abea3c ("can: kvaser_usb: Add support for the USBcan-II family")
Link: https://lore.kernel.org/all/20220603083820.800246-4-extja@kvaser.com
Cc: stable@vger.kernel.org
Signed-off-by: Jimmy Assarsson <extja@kvaser.com>
[mkl: remove stray netlink.h include]
[mkl: keep struct can_bittiming_const kvaser_usb_flexc_bittiming_const in kvaser_usb_hydra.c]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The firmware of M32C based Leaf devices expects bittiming parameters
calculated for 16MHz clock. Since we use the actual clock frequency of
the device, the device may end up with wrong bittiming parameters,
depending on user requested parameters.
This regression affects M32C based Leaf devices with non-16MHz clock.
Fixes: fb12797ab1 ("can: kvaser_usb: get CAN clock frequency from device")
Link: https://lore.kernel.org/all/20220603083820.800246-3-extja@kvaser.com
Cc: stable@vger.kernel.org
Signed-off-by: Jimmy Assarsson <extja@kvaser.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Unify and move compile-time known information into new struct
kvaser_usb_driver_info, in favor of run-time checks.
All Kvaser USBcanII supports listen-only mode and error counter
reporting.
Link: https://lore.kernel.org/all/20220603083820.800246-2-extja@kvaser.com
Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jimmy Assarsson <extja@kvaser.com>
[mkl: move struct kvaser_usb_driver_info into kvaser_usb_core.c]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In commit 1be37d3b04 ("can: m_can: fix periph RX path: use
rx-offload to ensure skbs are sent from softirq context") the RX path
for peripheral devices was switched to RX-offload.
Received CAN frames are pushed to RX-offload together with a
timestamp. RX-offload is designed to handle overflows of the timestamp
correctly, if 32 bit timestamps are provided.
The timestamps of m_can core are only 16 bits wide. So this patch
shifts them to full 32 bit before passing them to RX-offload.
Link: https://lore.kernel.org/all/20220612211410.4081390-1-mkl@pengutronix.de
Fixes: 1be37d3b04 ("can: m_can: fix periph RX path: use rx-offload to ensure skbs are sent from softirq context")
Cc: <stable@vger.kernel.org> # 5.13
Cc: Torin Cooper-Bennun <torin@maxiluxsystems.com>
Reviewed-by: Chandrasekar Ramakrishnan <rcsekar@samsung.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In commit df06fd6782 ("can: m_can: m_can_chip_config(): enable and
configure internal timestamps") the timestamping in the m_can core
should be enabled. In peripheral mode, the RX'ed CAN frames, TX
compete frames and error events are sorted by the timestamp.
The above mentioned commit however forgot to enable the timestamping.
Add the missing bits to enable the timestamp counter to the write of
the Timestamp Counter Configuration register.
Link: https://lore.kernel.org/all/20220612212708.4081756-1-mkl@pengutronix.de
Fixes: df06fd6782 ("can: m_can: m_can_chip_config(): enable and configure internal timestamps")
Cc: <stable@vger.kernel.org> # 5.13
Cc: Torin Cooper-Bennun <torin@maxiluxsystems.com>
Reviewed-by: Chandrasekar Ramakrishnan <rcsekar@samsung.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In grcan_probe(), of_find_node_by_path() has already increased the
refcount. There is no need to call of_node_get() again, so remove it.
Link: https://lore.kernel.org/all/20220619070257.4067022-1-windhl@126.com
Fixes: 1e93ed26ac ("can: grcan: grcan_probe(): fix broken system id check for errata workaround needs")
Cc: stable@vger.kernel.org # v5.18
Cc: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Liang He <windhl@126.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The gs_usb driver appears to suffer from a malady common to many USB
CAN adapter drivers in that it performs usb_alloc_coherent() to
allocate a number of USB request blocks (URBs) for RX, and then later
relies on usb_kill_anchored_urbs() to free them, but this doesn't
actually free them. As a result, this may be leaking DMA memory that's
been used by the driver.
This commit is an adaptation of the techniques found in the esd_usb2
driver where a similar design pattern led to a memory leak. It
explicitly frees the RX URBs and their DMA memory via a call to
usb_free_coherent(). Since the RX URBs were allocated in the
gs_can_open(), we remove them in gs_can_close() rather than in the
disconnect function as was done in esd_usb2.
For more information, see the 928150fad4 ("can: esd_usb2: fix memory
leak").
Link: https://lore.kernel.org/all/alpine.DEB.2.22.394.2206031547001.1630869@thelappy
Fixes: d08e973a77 ("can: gs_usb: Added support for the GS_USB CAN devices")
Cc: stable@vger.kernel.org
Signed-off-by: Rhett Aultman <rhett.aultman@samsara.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
On R-Car V3U, this driver should use suitable register offset instead of
other SoCs' one. Otherwise, data transmission failed on R-Car V3U.
Fixes: 45721c406d ("can: rcar_canfd: Add support for r8a779a0 SoC")
Link: https://lore.kernel.org/all/20220704074611.957191-1-yoshihiro.shimoda.uh@renesas.com
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Duy Nguyen <duy.nguyen.rh@renesas.com>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This reverts commit 05ca14fdb6.
On early silicon engineering samples observed bit shrinking issue when
we use brp as 1. Hence updated brp_min as 2. As in production silicon
this issue is fixed, so reverting the patch.
Link: https://lore.kernel.org/all/20220609082433.1191060-2-srinivas.neeli@xilinx.com
Signed-off-by: Srinivas Neeli <srinivas.neeli@xilinx.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch adds a private flag to the slcan driver to switch the
"err-rst-on-open" setting on and off.
"err-rst-on-open" on - Reset error states on opening command
"err-rst-on-open" off - Don't reset error states on opening command
(default)
The setting can only be changed if the interface is down:
ip link set dev can0 down
ethtool --set-priv-flags can0 err-rst-on-open {off|on}
ip link set dev can0 up
Link: https://lore.kernel.org/all/20220628163137.413025-11-dario.binacchi@amarulasolutions.com
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In case the bitrate has been set via ip tool, this patch changes the
driver to send the open ("O\r") and close ("C\r) commands to the
adapter.
Link: https://lore.kernel.org/all/20220628163137.413025-9-dario.binacchi@amarulasolutions.com
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>
It allows to set the bitrate via ip tool, as it happens for the other
CAN device drivers. It still remains possible to set the bitrate via
slcand or slcan_attach utilities. In case the ip tool is used, the
driver will send the serial command to the adapter.
Link: https://lore.kernel.org/all/20220628163137.413025-8-dario.binacchi@amarulasolutions.com
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>
This is a preparation patch for the upcoming support to change the
bitrate via ip tool, reset the adapter error states via the ethtool API
and, more generally, send commands to the adapter.
Since the close command (i. e. "C\r") will be sent in the ndo_stop()
where netif_running() returns false, a new flag bit (i. e. SLF_XCMD) for
serial transmission has to be added.
Link: https://lore.kernel.org/all/20220628163137.413025-7-dario.binacchi@amarulasolutions.com
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>
As suggested by commit [1], now the driver uses the functions and the
data structures provided by the CAN network device driver interface.
Currently the driver doesn't implement a way to set bitrate for SLCAN
based devices via ip tool, so you'll have to do this by slcand or
slcan_attach invocation through the -sX parameter:
- slcan_attach -f -s6 -o /dev/ttyACM0
- slcand -f -s8 -o /dev/ttyUSB0
where -s6 in will set adapter's bitrate to 500 Kbit/s and -s8 to
1Mbit/s.
See the table below for further CAN bitrates:
- s0 -> 10 Kbit/s
- s1 -> 20 Kbit/s
- s2 -> 50 Kbit/s
- s3 -> 100 Kbit/s
- s4 -> 125 Kbit/s
- s5 -> 250 Kbit/s
- s6 -> 500 Kbit/s
- s7 -> 800 Kbit/s
- s8 -> 1000 Kbit/s
In doing so, the struct can_priv::bittiming.bitrate of the driver is not
set and since the open_candev() checks that the bitrate has been set, it
must be a non-zero value, the bitrate is set to a fake value (-1U)
before it is called.
Using the rtnl_lock()/rtnl_unlock() functions has become a bit more
tricky as the register_candev() function indirectly calls rtnl_lock()
via register_netdev(). To avoid a deadlock it is therefore necessary to
call rtnl_unlock() before calling register_candev(). The same goes for
the unregister_candev() function.
[1] commit 39549eef35 ("can: CAN Network device driver and Netlink interface")
Link: https://lore.kernel.org/all/20220628163137.413025-6-dario.binacchi@amarulasolutions.com
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>
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>
It is used successfully by most (if not all) CAN device drivers. It
allows to remove replicated code.
Link: https://lore.kernel.org/all/20220628163137.413025-4-dario.binacchi@amarulasolutions.com
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>
