Merge tag 'linux-can-next-for-6.11-20240621' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next

Marc Kleine-Budde says:

====================
pull-request: can-next 2024-06-21

The first 2 patches are by Andy Shevchenko, one cleans up the includes
in the mcp251x driver, the other one updates the sja100 plx_pci driver
to make use of predefines PCI subvendor ID.

Mans Rullgard's patch cleans up the Kconfig help text of for the slcan
driver.

Oliver Hartkopp provides a patch to update the documentation, which
removes the ISO 15675-2 specification version where possible.

The next 2 patches are by Harini T and update the documentation of the
xilinx_can driver.

Francesco Valla provides documentation for the ISO 15765-2 protocol.

A patch by Dr. David Alan Gilbert removes an unused struct from the
mscan driver.

12 patches are by Martin Jocic. The first three add support for 3 new
devices to the kvaser_usb driver. The remaining 9 first clean up the
kvaser_pciefd driver, and then add support for MSI.

Krzysztof Kozlowski contributes 3 patches simplifies the CAN SPI
drivers by making use of spi_get_device_match_data().

The last patch is by Martin Hundebøll, which reworks the m_can driver
to not enable the CAN transceiver during probe.

* tag 'linux-can-next-for-6.11-20240621' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next: (24 commits)
can: m_can: don't enable transceiver when probing
can: mcp251xfd: simplify with spi_get_device_match_data()
can: mcp251x: simplify with spi_get_device_match_data()
can: hi311x: simplify with spi_get_device_match_data()
can: kvaser_pciefd: Add MSI interrupts
can: kvaser_pciefd: Move reset of DMA RX buffers to the end of the ISR
can: kvaser_pciefd: Change name of return code variable
can: kvaser_pciefd: Rename board_irq to pci_irq
can: kvaser_pciefd: Add unlikely
can: kvaser_pciefd: Add inline
can: kvaser_pciefd: Remove unnecessary comment
can: kvaser_pciefd: Skip redundant NULL pointer check in ISR
can: kvaser_pciefd: Group #defines together
can: kvaser_usb: Add support for Kvaser Mini PCIe 1xCAN
can: kvaser_usb: Add support for Kvaser USBcan Pro 5xCAN
can: kvaser_usb: Add support for Vining 800
can: mscan: remove unused struct 'mscan_state'
Documentation: networking: document ISO 15765-2
can: xilinx_can: Document driver description to list all supported IPs
can: isotp: remove ISO 15675-2 specification version where possible
...
====================

Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

Documentation/devicetree/bindings/net/can/xilinx,can.yaml

···
 $schema: http://devicetree.org/meta-schemas/core.yaml#
 
 title:
-  Xilinx Axi CAN/Zynq CANPS controller
+  Xilinx CAN and CANFD controller
 
 maintainers:
   - Appana Durga Kedareswara rao <[e-mail]>

Documentation/networking/index.rst

···
    caif/index
    ethtool-netlink
    ieee802154
+   iso15765-2
    j1939
    kapi
    msg_zerocopy

Documentation/networking/iso15765-2.rst

···
+.. SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+
+====================
+ISO 15765-2 (ISO-TP)
+====================
+
+Overview
+========
+
+ISO 15765-2, also known as ISO-TP, is a transport protocol specifically defined
+for diagnostic communication on CAN. It is widely used in the automotive
+industry, for example as the transport protocol for UDSonCAN (ISO 14229-3) or
+emission-related diagnostic services (ISO 15031-5).
+
+ISO-TP can be used both on CAN CC (aka Classical CAN) and CAN FD (CAN with
+Flexible Datarate) based networks. It is also designed to be compatible with a
+CAN network using SAE J1939 as data link layer (however, this is not a
+requirement).
+
+Specifications used
+-------------------
+
+* ISO 15765-2:2024 : Road vehicles - Diagnostic communication over Controller
+  Area Network (DoCAN). Part 2: Transport protocol and network layer services.
+
+Addressing
+----------
+
+In its simplest form, ISO-TP is based on two kinds of addressing modes for the
+nodes connected to the same network:
+
+* physical addressing is implemented by two node-specific addresses and is used
+  in 1-to-1 communication.
+
+* functional addressing is implemented by one node-specific address and is used
+  in 1-to-N communication.
+
+Three different addressing formats can be employed:
+
+* "normal" : each address is represented simply by a CAN ID.
+
+* "extended": each address is represented by a CAN ID plus the first byte of
+  the CAN payload; both the CAN ID and the byte inside the payload shall be
+  different between two addresses.
+
+* "mixed": each address is represented by a CAN ID plus the first byte of
+  the CAN payload; the CAN ID is different between two addresses, but the
+  additional byte is the same.
+
+Transport protocol and associated frame types
+---------------------------------------------
+
+When transmitting data using the ISO-TP protocol, the payload can either fit
+inside one single CAN message or not, also considering the overhead the protocol
+is generating and the optional extended addressing. In the first case, the data
+is transmitted at once using a so-called Single Frame (SF). In the second case,
+ISO-TP defines a multi-frame protocol, in which the sender provides (through a
+First Frame - FF) the PDU length which is to be transmitted and also asks for a
+Flow Control (FC) frame, which provides the maximum supported size of a macro
+data block (``blocksize``) and the minimum time between the single CAN messages
+composing such block (``stmin``). Once this information has been received, the
+sender starts to send frames containing fragments of the data payload (called
+Consecutive Frames - CF), stopping after every ``blocksize``-sized block to wait
+confirmation from the receiver which should then send another Flow Control
+frame to inform the sender about its availability to receive more data.
+
+How to Use ISO-TP
+=================
+
+As with others CAN protocols, the ISO-TP stack support is built into the
+Linux network subsystem for the CAN bus, aka. Linux-CAN or SocketCAN, and
+thus follows the same socket API.
+
+Creation and basic usage of an ISO-TP socket
+--------------------------------------------
+
+To use the ISO-TP stack, ``#include <linux/can/isotp.h>`` shall be used. A
+socket can then be created using the ``PF_CAN`` protocol family, the
+``SOCK_DGRAM`` type (as the underlying protocol is datagram-based by design)
+and the ``CAN_ISOTP`` protocol:
+
+.. code-block:: C
+
+    s = socket(PF_CAN, SOCK_DGRAM, CAN_ISOTP);
+
+After the socket has been successfully created, ``bind(2)`` shall be called to
+bind the socket to the desired CAN interface; to do so:
+
+* a TX CAN ID shall be specified as part of the sockaddr supplied to the call
+  itself.
+
+* a RX CAN ID shall also be specified, unless broadcast flags have been set
+  through socket option (explained below).
+
+Once bound to an interface, the socket can be read from and written to using
+the usual ``read(2)`` and ``write(2)`` system calls, as well as ``send(2)``,
+``sendmsg(2)``, ``recv(2)`` and ``recvmsg(2)``.
+Unlike the CAN_RAW socket API, only the ISO-TP data field (the actual payload)
+is sent and received by the userspace application using these calls. The address
+information and the protocol information are automatically filled by the ISO-TP
+stack using the configuration supplied during socket creation. In the same way,
+the stack will use the transport mechanism when required (i.e., when the size
+of the data payload exceeds the MTU of the underlying CAN bus).
+
+The sockaddr structure used for SocketCAN has extensions for use with ISO-TP,
+as specified below:
+
+.. code-block:: C
+
+    struct sockaddr_can {
+        sa_family_t can_family;
+        int         can_ifindex;
+        union {
+            struct { canid_t rx_id, tx_id; } tp;
+        ...
+        } can_addr;
+    }
+
+* ``can_family`` and ``can_ifindex`` serve the same purpose as for other
+  SocketCAN sockets.
+
+* ``can_addr.tp.rx_id`` specifies the receive (RX) CAN ID and will be used as
+  a RX filter.
+
+* ``can_addr.tp.tx_id`` specifies the transmit (TX) CAN ID
+
+ISO-TP socket options
+---------------------
+
+When creating an ISO-TP socket, reasonable defaults are set. Some options can
+be modified with ``setsockopt(2)`` and/or read back with ``getsockopt(2)``.
+
+General options
+~~~~~~~~~~~~~~~
+
+General socket options can be passed using the ``CAN_ISOTP_OPTS`` optname:
+
+.. code-block:: C
+
+    struct can_isotp_options opts;
+    ret = setsockopt(s, SOL_CAN_ISOTP, CAN_ISOTP_OPTS, &opts, sizeof(opts))
+
+where the ``can_isotp_options`` structure has the following contents:
+
+.. code-block:: C
+
+    struct can_isotp_options {
+        u32 flags;
+        u32 frame_txtime;
+        u8  ext_address;
+        u8  txpad_content;
+        u8  rxpad_content;
+        u8  rx_ext_address;
+    };
+
+* ``flags``: modifiers to be applied to the default behaviour of the ISO-TP
+  stack. Following flags are available:
+
+  * ``CAN_ISOTP_LISTEN_MODE``: listen only (do not send FC frames); normally
+    used as a testing feature.
+
+  * ``CAN_ISOTP_EXTEND_ADDR``: use the byte specified in ``ext_address`` as an
+    additional address component. This enables the "mixed" addressing format if
+    used alone, or the "extended" addressing format if used in conjunction with
+    ``CAN_ISOTP_RX_EXT_ADDR``.
+
+  * ``CAN_ISOTP_TX_PADDING``: enable padding for transmitted frames, using
+    ``txpad_content`` as value for the padding bytes.
+
+  * ``CAN_ISOTP_RX_PADDING``: enable padding for the received frames, using
+    ``rxpad_content`` as value for the padding bytes.
+
+  * ``CAN_ISOTP_CHK_PAD_LEN``: check for correct padding length on the received
+    frames.
+
+  * ``CAN_ISOTP_CHK_PAD_DATA``: check padding bytes on the received frames
+    against ``rxpad_content``; if ``CAN_ISOTP_RX_PADDING`` is not specified,
+    this flag is ignored.
+
+  * ``CAN_ISOTP_HALF_DUPLEX``: force ISO-TP socket in half duplex mode
+    (that is, transport mechanism can only be incoming or outgoing at the same
+    time, not both).
+
+  * ``CAN_ISOTP_FORCE_TXSTMIN``: ignore stmin from received FC; normally
+    used as a testing feature.
+
+  * ``CAN_ISOTP_FORCE_RXSTMIN``: ignore CFs depending on rx stmin; normally
+    used as a testing feature.
+
+  * ``CAN_ISOTP_RX_EXT_ADDR``: use ``rx_ext_address`` instead of ``ext_address``
+    as extended addressing byte on the reception path. If used in conjunction
+    with ``CAN_ISOTP_EXTEND_ADDR``, this flag effectively enables the "extended"
+    addressing format.
+
+  * ``CAN_ISOTP_WAIT_TX_DONE``: wait until the frame is sent before returning
+    from ``write(2)`` and ``send(2)`` calls (i.e., blocking write operations).
+
+  * ``CAN_ISOTP_SF_BROADCAST``: use 1-to-N functional addressing (cannot be
+    specified alongside ``CAN_ISOTP_CF_BROADCAST``).
+
+  * ``CAN_ISOTP_CF_BROADCAST``: use 1-to-N transmission without flow control
+    (cannot be specified alongside ``CAN_ISOTP_SF_BROADCAST``).
+    NOTE: this is not covered by the ISO 15765-2 standard.
+
+  * ``CAN_ISOTP_DYN_FC_PARMS``: enable dynamic update of flow control
+    parameters.
+
+* ``frame_txtime``: frame transmission time (defined as N_As/N_Ar inside the
+  ISO standard); if ``0``, the default (or the last set value) is used.
+  To set the transmission time to ``0``, the ``CAN_ISOTP_FRAME_TXTIME_ZERO``
+  macro (equal to 0xFFFFFFFF) shall be used.
+
+* ``ext_address``: extended addressing byte, used if the
+  ``CAN_ISOTP_EXTEND_ADDR`` flag is specified.
+
+* ``txpad_content``: byte used as padding value for transmitted frames.
+
+* ``rxpad_content``: byte used as padding value for received frames.
+
+* ``rx_ext_address``: extended addressing byte for the reception path, used if
+  the ``CAN_ISOTP_RX_EXT_ADDR`` flag is specified.
+
+Flow Control options
+~~~~~~~~~~~~~~~~~~~~
+
+Flow Control (FC) options can be passed using the ``CAN_ISOTP_RECV_FC`` optname
+to provide the communication parameters for receiving ISO-TP PDUs.
+
+.. code-block:: C
+
+    struct can_isotp_fc_options fc_opts;
+    ret = setsockopt(s, SOL_CAN_ISOTP, CAN_ISOTP_RECV_FC, &fc_opts, sizeof(fc_opts));
+
+where the ``can_isotp_fc_options`` structure has the following contents:
+
+.. code-block:: C
+
+    struct can_isotp_options {
+        u8 bs;
+        u8 stmin;
+        u8 wftmax;
+    };
+
+* ``bs``: blocksize provided in flow control frames.
+
+* ``stmin``: minimum separation time provided in flow control frames; can
+  have the following values (others are reserved):
+
+  * 0x00 - 0x7F : 0 - 127 ms
+
+  * 0xF1 - 0xF9 : 100 us - 900 us
+
+* ``wftmax``: maximum number of wait frames provided in flow control frames.
+
+Link Layer options
+~~~~~~~~~~~~~~~~~~
+
+Link Layer (LL) options can be passed using the ``CAN_ISOTP_LL_OPTS`` optname:
+
+.. code-block:: C
+
+    struct can_isotp_ll_options ll_opts;
+    ret = setsockopt(s, SOL_CAN_ISOTP, CAN_ISOTP_LL_OPTS, &ll_opts, sizeof(ll_opts));
+
+where the ``can_isotp_ll_options`` structure has the following contents:
+
+.. code-block:: C
+
+    struct can_isotp_ll_options {
+        u8 mtu;
+        u8 tx_dl;
+        u8 tx_flags;
+    };
+
+* ``mtu``: generated and accepted CAN frame type, can be equal to ``CAN_MTU``
+  for classical CAN frames or ``CANFD_MTU`` for CAN FD frames.
+
+* ``tx_dl``: maximum payload length for transmitted frames, can have one value
+  among: 8, 12, 16, 20, 24, 32, 48, 64. Values above 8 only apply to CAN FD
+  traffic (i.e.: ``mtu = CANFD_MTU``).
+
+* ``tx_flags``: flags set into ``struct canfd_frame.flags`` at frame creation.
+  Only applies to CAN FD traffic (i.e.: ``mtu = CANFD_MTU``).
+
+Transmission stmin
+~~~~~~~~~~~~~~~~~~
+
+The transmission minimum separation time (stmin) can be forced using the
+``CAN_ISOTP_TX_STMIN`` optname and providing an stmin value in microseconds as
+a 32bit unsigned integer; this will overwrite the value sent by the receiver in
+flow control frames:
+
+.. code-block:: C
+
+    uint32_t stmin;
+    ret = setsockopt(s, SOL_CAN_ISOTP, CAN_ISOTP_TX_STMIN, &stmin, sizeof(stmin));
+
+Reception stmin
+~~~~~~~~~~~~~~~
+
+The reception minimum separation time (stmin) can be forced using the
+``CAN_ISOTP_RX_STMIN`` optname and providing an stmin value in microseconds as
+a 32bit unsigned integer; received Consecutive Frames (CF) which timestamps
+differ less than this value will be ignored:
+
+.. code-block:: C
+
+    uint32_t stmin;
+    ret = setsockopt(s, SOL_CAN_ISOTP, CAN_ISOTP_RX_STMIN, &stmin, sizeof(stmin));
+
+Multi-frame transport support
+-----------------------------
+
+The ISO-TP stack contained inside the Linux kernel supports the multi-frame
+transport mechanism defined by the standard, with the following constraints:
+
+* the maximum size of a PDU is defined by a module parameter, with an hard
+  limit imposed at build time.
+
+* when a transmission is in progress, subsequent calls to ``write(2)`` will
+  block, while calls to ``send(2)`` will either block or fail depending on the
+  presence of the ``MSG_DONTWAIT`` flag.
+
+* no support is present for sending "wait frames": whether a PDU can be fully
+  received or not is decided when the First Frame is received.
+
+Errors
+------
+
+Following errors are reported to userspace:
+
+RX path errors
+~~~~~~~~~~~~~~
+
+============ ===============================================================
+-ETIMEDOUT   timeout of data reception
+-EILSEQ      sequence number mismatch during a multi-frame reception
+-EBADMSG     data reception with wrong padding
+============ ===============================================================
+
+TX path errors
+~~~~~~~~~~~~~~
+
+========== =================================================================
+-ECOMM     flow control reception timeout
+-EMSGSIZE  flow control reception overflow
+-EBADMSG   flow control reception with wrong layout/padding
+========== =================================================================
+
+Examples
+========
+
+Basic node example
+------------------
+
+Following example implements a node using "normal" physical addressing, with
+RX ID equal to 0x18DAF142 and a TX ID equal to 0x18DA42F1. All options are left
+to their default.
+
+.. code-block:: C
+
+  int s;
+  struct sockaddr_can addr;
+  int ret;
+
+  s = socket(PF_CAN, SOCK_DGRAM, CAN_ISOTP);
+  if (s < 0)
+      exit(1);
+
+  addr.can_family = AF_CAN;
+  addr.can_ifindex = if_nametoindex("can0");
+  addr.tp.tx_id = 0x18DA42F1 | CAN_EFF_FLAG;
+  addr.tp.rx_id = 0x18DAF142 | CAN_EFF_FLAG;
+
+  ret = bind(s, (struct sockaddr *)&addr, sizeof(addr));
+  if (ret < 0)
+      exit(1);
+
+  /* Data can now be received using read(s, ...) and sent using write(s, ...) */
+
+Additional examples
+-------------------
+
+More complete (and complex) examples can be found inside the ``isotp*`` userland
+tools, distributed as part of the ``can-utils`` utilities at:
+https://github.com/linux-can/can-utils

MAINTAINERS

···
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can.git
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next.git
 F:	Documentation/networking/can.rst
+F:	Documentation/networking/iso15765-2.rst
 F:	include/linux/can/can-ml.h
 F:	include/linux/can/core.h
 F:	include/linux/can/skb.h

drivers/net/can/Kconfig

···
 	  slcand) can be found in the can-utils at the linux-can project, see
 	  https://github.com/linux-can/can-utils for details.
 
-	  The slcan driver supports up to 10 CAN netdevices by default which
-	  can be changed by the 'maxdev=xx' module option. This driver can
-	  also be built as a module. If so, the module will be called slcan.
+	  This driver can also be built as a module. If so, the module
+	  will be called slcan.
 
 config CAN_SUN4I
 	tristate "Allwinner A10 CAN controller"

drivers/net/can/kvaser_pciefd.c

···
 #define KVASER_PCIEFD_CAN_TX_MAX_COUNT 17U
 #define KVASER_PCIEFD_MAX_CAN_CHANNELS 8UL
 #define KVASER_PCIEFD_DMA_COUNT 2U
-
 #define KVASER_PCIEFD_DMA_SIZE (4U * 1024U)
 
 #define KVASER_PCIEFD_VENDOR 0x1a07
+
 /* Altera based devices */
 #define KVASER_PCIEFD_4HS_DEVICE_ID 0x000d
 #define KVASER_PCIEFD_2HS_V2_DEVICE_ID 0x000e
···
 	spin_unlock_irqrestore(&can->lock, irq);
 }
 
-static void kvaser_pciefd_set_tx_irq(struct kvaser_pciefd_can *can)
+static inline void kvaser_pciefd_set_tx_irq(struct kvaser_pciefd_can *can)
 {
 	u32 msk;
 
···
 
 static int kvaser_pciefd_open(struct net_device *netdev)
 {
-	int err;
+	int ret;
 	struct kvaser_pciefd_can *can = netdev_priv(netdev);
 
-	err = open_candev(netdev);
-	if (err)
-		return err;
+	ret = open_candev(netdev);
+	if (ret)
+		return ret;
 
-	err = kvaser_pciefd_bus_on(can);
-	if (err) {
+	ret = kvaser_pciefd_bus_on(can);
+	if (ret) {
 		close_candev(netdev);
-		return err;
+		return ret;
 	}
 
 	return 0;
···
 	int i;
 
 	for (i = 0; i < pcie->nr_channels; i++) {
-		int err = register_candev(pcie->can[i]->can.dev);
+		int ret = register_candev(pcie->can[i]->can.dev);
 
-		if (err) {
+		if (ret) {
 			int j;
 
 			/* Unregister all successfully registered devices. */
 			for (j = 0; j < i; j++)
 				unregister_candev(pcie->can[j]->can.dev);
-			return err;
+			return ret;
 		}
 	}
 
···
 	/* Position does not point to the end of the package,
 	 * corrupted packet size?
 	 */
-	if ((*start_pos + size) != pos)
+	if (unlikely((*start_pos + size) != pos))
 		return -EIO;
 
 	/* Point to the next packet header, if any */
···
 	return res;
 }
 
-static void kvaser_pciefd_receive_irq(struct kvaser_pciefd *pcie)
+static u32 kvaser_pciefd_receive_irq(struct kvaser_pciefd *pcie)
 {
 	u32 irq = ioread32(KVASER_PCIEFD_SRB_ADDR(pcie) + KVASER_PCIEFD_SRB_IRQ_REG);
 
-	if (irq & KVASER_PCIEFD_SRB_IRQ_DPD0) {
+	if (irq & KVASER_PCIEFD_SRB_IRQ_DPD0)
 		kvaser_pciefd_read_buffer(pcie, 0);
-		/* Reset DMA buffer 0 */
-		iowrite32(KVASER_PCIEFD_SRB_CMD_RDB0,
-			  KVASER_PCIEFD_SRB_ADDR(pcie) + KVASER_PCIEFD_SRB_CMD_REG);
-	}
 
-	if (irq & KVASER_PCIEFD_SRB_IRQ_DPD1) {
+	if (irq & KVASER_PCIEFD_SRB_IRQ_DPD1)
 		kvaser_pciefd_read_buffer(pcie, 1);
-		/* Reset DMA buffer 1 */
-		iowrite32(KVASER_PCIEFD_SRB_CMD_RDB1,
-			  KVASER_PCIEFD_SRB_ADDR(pcie) + KVASER_PCIEFD_SRB_CMD_REG);
-	}
 
-	if (irq & KVASER_PCIEFD_SRB_IRQ_DOF0 ||
-	    irq & KVASER_PCIEFD_SRB_IRQ_DOF1 ||
-	    irq & KVASER_PCIEFD_SRB_IRQ_DUF0 ||
-	    irq & KVASER_PCIEFD_SRB_IRQ_DUF1)
+	if (unlikely(irq & KVASER_PCIEFD_SRB_IRQ_DOF0 ||
+		     irq & KVASER_PCIEFD_SRB_IRQ_DOF1 ||
+		     irq & KVASER_PCIEFD_SRB_IRQ_DUF0 ||
+		     irq & KVASER_PCIEFD_SRB_IRQ_DUF1))
 		dev_err(&pcie->pci->dev, "DMA IRQ error 0x%08X\n", irq);
 
 	iowrite32(irq, KVASER_PCIEFD_SRB_ADDR(pcie) + KVASER_PCIEFD_SRB_IRQ_REG);
+	return irq;
 }
 
 static void kvaser_pciefd_transmit_irq(struct kvaser_pciefd_can *can)
···
 {
 	struct kvaser_pciefd *pcie = (struct kvaser_pciefd *)dev;
 	const struct kvaser_pciefd_irq_mask *irq_mask = pcie->driver_data->irq_mask;
-	u32 board_irq = ioread32(KVASER_PCIEFD_PCI_IRQ_ADDR(pcie));
+	u32 pci_irq = ioread32(KVASER_PCIEFD_PCI_IRQ_ADDR(pcie));
+	u32 srb_irq = 0;
 	int i;
 
-	if (!(board_irq & irq_mask->all))
+	if (!(pci_irq & irq_mask->all))
 		return IRQ_NONE;
 
-	if (board_irq & irq_mask->kcan_rx0)
-		kvaser_pciefd_receive_irq(pcie);
+	if (pci_irq & irq_mask->kcan_rx0)
+		srb_irq = kvaser_pciefd_receive_irq(pcie);
 
 	for (i = 0; i < pcie->nr_channels; i++) {
-		if (!pcie->can[i]) {
-			dev_err(&pcie->pci->dev,
-				"IRQ mask points to unallocated controller\n");
-			break;
-		}
-
-		/* Check that mask matches channel (i) IRQ mask */
-		if (board_irq & irq_mask->kcan_tx[i])
+		if (pci_irq & irq_mask->kcan_tx[i])
 			kvaser_pciefd_transmit_irq(pcie->can[i]);
+	}
+
+	if (srb_irq & KVASER_PCIEFD_SRB_IRQ_DPD0) {
+		/* Reset DMA buffer 0, may trigger new interrupt */
+		iowrite32(KVASER_PCIEFD_SRB_CMD_RDB0,
+			  KVASER_PCIEFD_SRB_ADDR(pcie) + KVASER_PCIEFD_SRB_CMD_REG);
+	}
+
+	if (srb_irq & KVASER_PCIEFD_SRB_IRQ_DPD1) {
+		/* Reset DMA buffer 1, may trigger new interrupt */
+		iowrite32(KVASER_PCIEFD_SRB_CMD_RDB1,
+			  KVASER_PCIEFD_SRB_ADDR(pcie) + KVASER_PCIEFD_SRB_CMD_REG);
 	}
 
 	return IRQ_HANDLED;
···
 static int kvaser_pciefd_probe(struct pci_dev *pdev,
 			       const struct pci_device_id *id)
 {
-	int err;
+	int ret;
 	struct kvaser_pciefd *pcie;
 	const struct kvaser_pciefd_irq_mask *irq_mask;
 	void __iomem *irq_en_base;
···
 	pcie->driver_data = (const struct kvaser_pciefd_driver_data *)id->driver_data;
 	irq_mask = pcie->driver_data->irq_mask;
 
-	err = pci_enable_device(pdev);
-	if (err)
-		return err;
+	ret = pci_enable_device(pdev);
+	if (ret)
+		return ret;
 
-	err = pci_request_regions(pdev, KVASER_PCIEFD_DRV_NAME);
-	if (err)
+	ret = pci_request_regions(pdev, KVASER_PCIEFD_DRV_NAME);
+	if (ret)
 		goto err_disable_pci;
 
 	pcie->reg_base = pci_iomap(pdev, 0, 0);
 	if (!pcie->reg_base) {
-		err = -ENOMEM;
+		ret = -ENOMEM;
 		goto err_release_regions;
 	}
 
-	err = kvaser_pciefd_setup_board(pcie);
-	if (err)
+	ret = kvaser_pciefd_setup_board(pcie);
+	if (ret)
 		goto err_pci_iounmap;
 
-	err = kvaser_pciefd_setup_dma(pcie);
-	if (err)
+	ret = kvaser_pciefd_setup_dma(pcie);
+	if (ret)
 		goto err_pci_iounmap;
 
 	pci_set_master(pdev);
 
-	err = kvaser_pciefd_setup_can_ctrls(pcie);
-	if (err)
+	ret = kvaser_pciefd_setup_can_ctrls(pcie);
+	if (ret)
 		goto err_teardown_can_ctrls;
 
-	err = request_irq(pcie->pci->irq, kvaser_pciefd_irq_handler,
+	ret = pci_alloc_irq_vectors(pcie->pci, 1, 1, PCI_IRQ_INTX | PCI_IRQ_MSI);
+	if (ret < 0) {
+		dev_err(&pcie->pci->dev, "Failed to allocate IRQ vectors.\n");
+		goto err_teardown_can_ctrls;
+	}
+
+	ret = pci_irq_vector(pcie->pci, 0);
+	if (ret < 0)
+		goto err_pci_free_irq_vectors;
+
+	pcie->pci->irq = ret;
+
+	ret = request_irq(pcie->pci->irq, kvaser_pciefd_irq_handler,
 			  IRQF_SHARED, KVASER_PCIEFD_DRV_NAME, pcie);
-	if (err)
-		goto err_teardown_can_ctrls;
-
+	if (ret) {
+		dev_err(&pcie->pci->dev, "Failed to request IRQ %d\n", pcie->pci->irq);
+		goto err_pci_free_irq_vectors;
+	}
 	iowrite32(KVASER_PCIEFD_SRB_IRQ_DPD0 | KVASER_PCIEFD_SRB_IRQ_DPD1,
 		  KVASER_PCIEFD_SRB_ADDR(pcie) + KVASER_PCIEFD_SRB_IRQ_REG);
 
···
 	iowrite32(KVASER_PCIEFD_SRB_CMD_RDB1,
 		  KVASER_PCIEFD_SRB_ADDR(pcie) + KVASER_PCIEFD_SRB_CMD_REG);
 
-	err = kvaser_pciefd_reg_candev(pcie);
-	if (err)
+	ret = kvaser_pciefd_reg_candev(pcie);
+	if (ret)
 		goto err_free_irq;
 
 	return 0;
···
 	/* Disable PCI interrupts */
 	iowrite32(0, irq_en_base);
 	free_irq(pcie->pci->irq, pcie);
+
+err_pci_free_irq_vectors:
+	pci_free_irq_vectors(pcie->pci);
 
 err_teardown_can_ctrls:
 	kvaser_pciefd_teardown_can_ctrls(pcie);
···
 err_disable_pci:
 	pci_disable_device(pdev);
 
-	return err;
+	return ret;
 }
 
 static void kvaser_pciefd_remove_all_ctrls(struct kvaser_pciefd *pcie)
···
 	iowrite32(0, KVASER_PCIEFD_PCI_IEN_ADDR(pcie));
 
 	free_irq(pcie->pci->irq, pcie);
-
+	pci_free_irq_vectors(pcie->pci);
 	pci_iounmap(pdev, pcie->reg_base);
 	pci_release_regions(pdev);
 	pci_disable_device(pdev);

drivers/net/can/m_can/m_can.c

···
 	return cdev->ops->read_fifo(cdev, addr_offset, val, 1);
 }
 
-static void m_can_config_endisable(struct m_can_classdev *cdev, bool enable)
+static int m_can_cccr_update_bits(struct m_can_classdev *cdev, u32 mask, u32 val)
 {
-	u32 cccr = m_can_read(cdev, M_CAN_CCCR);
-	u32 timeout = 10;
-	u32 val = 0;
+	u32 val_before = m_can_read(cdev, M_CAN_CCCR);
+	u32 val_after = (val_before & ~mask) | val;
+	size_t tries = 10;
 
-	/* Clear the Clock stop request if it was set */
-	if (cccr & CCCR_CSR)
-		cccr &= ~CCCR_CSR;
-
-	if (enable) {
-		/* enable m_can configuration */
-		m_can_write(cdev, M_CAN_CCCR, cccr | CCCR_INIT);
-		udelay(5);
-		/* CCCR.CCE can only be set/reset while CCCR.INIT = '1' */
-		m_can_write(cdev, M_CAN_CCCR, cccr | CCCR_INIT | CCCR_CCE);
-	} else {
-		m_can_write(cdev, M_CAN_CCCR, cccr & ~(CCCR_INIT | CCCR_CCE));
+	if (!(mask & CCCR_INIT) && !(val_before & CCCR_INIT)) {
+		dev_err(cdev->dev,
+			"refusing to configure device when in normal mode\n");
+		return -EBUSY;
 	}
 
-	/* there's a delay for module initialization */
-	if (enable)
-		val = CCCR_INIT | CCCR_CCE;
+	/* The chip should be in standby mode when changing the CCCR register,
+	 * and some chips set the CSR and CSA bits when in standby. Furthermore,
+	 * the CSR and CSA bits should be written as zeros, even when they read
+	 * ones.
+	 */
+	val_after &= ~(CCCR_CSR | CCCR_CSA);
 
-	while ((m_can_read(cdev, M_CAN_CCCR) & (CCCR_INIT | CCCR_CCE)) != val) {
-		if (timeout == 0) {
-			netdev_warn(cdev->net, "Failed to init module\n");
-			return;
-		}
-		timeout--;
-		udelay(1);
+	while (tries--) {
+		u32 val_read;
+
+		/* Write the desired value in each try, as setting some bits in
+		 * the CCCR register require other bits to be set first. E.g.
+		 * setting the NISO bit requires setting the CCE bit first.
+		 */
+		m_can_write(cdev, M_CAN_CCCR, val_after);
+
+		val_read = m_can_read(cdev, M_CAN_CCCR) & ~(CCCR_CSR | CCCR_CSA);
+
+		if (val_read == val_after)
+			return 0;
+
+		usleep_range(1, 5);
 	}
+
+	return -ETIMEDOUT;
+}
+
+static int m_can_config_enable(struct m_can_classdev *cdev)
+{
+	int err;
+
+	/* CCCR_INIT must be set in order to set CCCR_CCE, but access to
+	 * configuration registers should only be enabled when in standby mode,
+	 * where CCCR_INIT is always set.
+	 */
+	err = m_can_cccr_update_bits(cdev, CCCR_CCE, CCCR_CCE);
+	if (err)
+		netdev_err(cdev->net, "failed to enable configuration mode\n");
+
+	return err;
+}
+
+static int m_can_config_disable(struct m_can_classdev *cdev)
+{
+	int err;
+
+	/* Only clear CCCR_CCE, since CCCR_INIT cannot be cleared while in
+	 * standby mode
+	 */
+	err = m_can_cccr_update_bits(cdev, CCCR_CCE, 0);
+	if (err)
+		netdev_err(cdev->net, "failed to disable configuration registers\n");
+
+	return err;
 }
 
 static void m_can_interrupt_enable(struct m_can_classdev *cdev, u32 interrupts)
···
 	interrupts &= ~(IR_ARA | IR_ELO | IR_DRX | IR_TEFF | IR_TFE | IR_TCF |
 			IR_HPM | IR_RF1F | IR_RF1W | IR_RF1N | IR_RF0F);
 
-	m_can_config_endisable(cdev, true);
+	err = m_can_config_enable(cdev);
+	if (err)
+		return err;
 
 	/* RX Buffer/FIFO Element Size 64 bytes data field */
 	m_can_write(cdev, M_CAN_RXESC,
···
 		    FIELD_PREP(TSCC_TCP_MASK, 0xf) |
 		    FIELD_PREP(TSCC_TSS_MASK, TSCC_TSS_INTERNAL));
 
-	m_can_config_endisable(cdev, false);
+	err = m_can_config_disable(cdev);
+	if (err)
+		return err;
 
 	if (cdev->ops->init)
 		cdev->ops->init(cdev);
···
 		cdev->tx_fifo_putidx = FIELD_GET(TXFQS_TFQPI_MASK,
 						 m_can_read(cdev, M_CAN_TXFQS));
 
-	return 0;
+	ret = m_can_cccr_update_bits(cdev, CCCR_INIT, 0);
+	if (ret)
+		netdev_err(dev, "failed to enter normal mode\n");
+
+	return ret;
 }
 
 static int m_can_set_mode(struct net_device *dev, enum can_mode mode)
···
 }
 
 /* Selectable Non ISO support only in version 3.2.x
- * This function checks if the bit is writable.
+ * Return 1 if the bit is writable, 0 if it is not, or negative on error.
  */
-static bool m_can_niso_supported(struct m_can_classdev *cdev)
+static int m_can_niso_supported(struct m_can_classdev *cdev)
 {
-	u32 cccr_reg, cccr_poll = 0;
-	int niso_timeout = -ETIMEDOUT;
-	int i;
+	int ret, niso;
 
-	m_can_config_endisable(cdev, true);
-	cccr_reg = m_can_read(cdev, M_CAN_CCCR);
-	cccr_reg |= CCCR_NISO;
-	m_can_write(cdev, M_CAN_CCCR, cccr_reg);
+	ret = m_can_config_enable(cdev);
+	if (ret)
+		return ret;
 
-	for (i = 0; i <= 10; i++) {
-		cccr_poll = m_can_read(cdev, M_CAN_CCCR);
-		if (cccr_poll == cccr_reg) {
-			niso_timeout = 0;
-			break;
-		}
+	/* First try to set the NISO bit. */
+	niso = m_can_cccr_update_bits(cdev, CCCR_NISO, CCCR_NISO);
 
-		usleep_range(1, 5);
+	/* Then clear the it again. */
+	ret = m_can_cccr_update_bits(cdev, CCCR_NISO, 0);
+	if (ret) {
+		dev_err(cdev->dev, "failed to revert the NON-ISO bit in CCCR\n");
+		return ret;
 	}
 
-	/* Clear NISO */
-	cccr_reg &= ~(CCCR_NISO);
-	m_can_write(cdev, M_CAN_CCCR, cccr_reg);
+	ret = m_can_config_disable(cdev);
+	if (ret)
+		return ret;
 
-	m_can_config_endisable(cdev, false);
-
-	/* return false if time out (-ETIMEDOUT), else return true */
-	return !niso_timeout;
+	return niso == 0;
 }
 
 static int m_can_dev_setup(struct m_can_classdev *cdev)
 {
 	struct net_device *dev = cdev->net;
-	int m_can_version, err;
+	int m_can_version, err, niso;
 
 	m_can_version = m_can_check_core_release(cdev);
 	/* return if unsupported version */
···
 		cdev->can.bittiming_const = &m_can_bittiming_const_31X;
 		cdev->can.data_bittiming_const = &m_can_data_bittiming_const_31X;
 
-		cdev->can.ctrlmode_supported |=
-			(m_can_niso_supported(cdev) ?
-			 CAN_CTRLMODE_FD_NON_ISO : 0);
+		niso = m_can_niso_supported(cdev);
+		if (niso < 0)
+			return niso;
+		if (niso)
+			cdev->can.ctrlmode_supported |= CAN_CTRLMODE_FD_NON_ISO;
 		break;
 	default:
 		dev_err(cdev->dev, "Unsupported version number: %2d",
···
 		return -EINVAL;
 	}
 
-	if (cdev->ops->init)
-		cdev->ops->init(cdev);
-
-	return 0;
+	/* Forcing standby mode should be redundant, as the chip should be in
+	 * standby after a reset. Write the INIT bit anyways, should the chip
+	 * be configured by previous stage.
+	 */
+	return m_can_cccr_update_bits(cdev, CCCR_INIT, CCCR_INIT);
 }
 
 static void m_can_stop(struct net_device *dev)
 {
 	struct m_can_classdev *cdev = netdev_priv(dev);
+	int ret;
 
 	/* disable all interrupts */
 	m_can_disable_all_interrupts(cdev);
 
 	/* Set init mode to disengage from the network */
-	m_can_config_endisable(cdev, true);
+	ret = m_can_cccr_update_bits(cdev, CCCR_INIT, CCCR_INIT);
+	if (ret)
+		netdev_err(dev, "failed to enter standby mode: %pe\n",
+			   ERR_PTR(ret));
 
 	/* set the state as STOPPED */
 	cdev->can.state = CAN_STATE_STOPPED;

drivers/net/can/m_can/tcan4x5x-core.c

···
 		goto out_power;
 	}
 
-	ret = tcan4x5x_init(mcan_class);
+	tcan4x5x_check_wake(priv);
+
+	ret = tcan4x5x_write_tcan_reg(mcan_class, TCAN4X5X_INT_EN, 0);
 	if (ret) {
-		dev_err(&spi->dev, "tcan initialization failed %pe\n",
-			ERR_PTR(ret));
+		dev_err(&spi->dev, "Disabling interrupts failed %pe\n", ERR_PTR(ret));
+		goto out_power;
+	}
+
+	ret = tcan4x5x_clear_interrupts(mcan_class);
+	if (ret) {
+		dev_err(&spi->dev, "Clearing interrupts failed %pe\n", ERR_PTR(ret));
 		goto out_power;
 	}
 

drivers/net/can/mscan/mscan.c

···
 	.brp_inc = 1,
 };
 
-struct mscan_state {
-	u8 mode;
-	u8 canrier;
-	u8 cantier;
-};
-
 static enum can_state state_map[] = {
 	CAN_STATE_ERROR_ACTIVE,
 	CAN_STATE_ERROR_WARNING,

drivers/net/can/sja1000/plx_pci.c

···
 #define TEWS_PCI_VENDOR_ID		0x1498
 #define TEWS_PCI_DEVICE_ID_TMPC810	0x032A
 
-#define CTI_PCI_VENDOR_ID		0x12c4
 #define CTI_PCI_DEVICE_ID_CRG001	0x0900
 
 #define MOXA_PCI_VENDOR_ID		0x1393
···
 	{
 		/* Connect Tech Inc. CANpro/104-Plus Opto (CRG001) card */
 		PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9030,
-		CTI_PCI_VENDOR_ID, CTI_PCI_DEVICE_ID_CRG001,
+		PCI_SUBVENDOR_ID_CONNECT_TECH, CTI_PCI_DEVICE_ID_CRG001,
 		0, 0,
 		(kernel_ulong_t)&plx_pci_card_info_cti
 	},

drivers/net/can/spi/hi311x.c

···
 	struct device *dev = &spi->dev;
 	struct net_device *net;
 	struct hi3110_priv *priv;
-	const void *match;
 	struct clk *clk;
 	u32 freq;
 	int ret;
···
 		CAN_CTRLMODE_LISTENONLY |
 		CAN_CTRLMODE_BERR_REPORTING;
 
-	match = device_get_match_data(dev);
-	if (match)
-		priv->model = (enum hi3110_model)(uintptr_t)match;
-	else
-		priv->model = spi_get_device_id(spi)->driver_data;
+	priv->model = (enum hi3110_model)(uintptr_t)spi_get_device_match_data(spi);
 	priv->net = net;
 	priv->clk = clk;
 

drivers/net/can/spi/mcp251x.c

···
 #include <linux/device.h>
 #include <linux/ethtool.h>
 #include <linux/freezer.h>
-#include <linux/gpio.h>
 #include <linux/gpio/driver.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
···
 				      unsigned int offset)
 {
 	if (mcp251x_gpio_is_input(offset))
-		return GPIOF_DIR_IN;
+		return GPIO_LINE_DIRECTION_IN;
 
-	return GPIOF_DIR_OUT;
+	return GPIO_LINE_DIRECTION_OUT;
 }
 
 static int mcp251x_gpio_get(struct gpio_chip *chip, unsigned int offset)
···
 
 static int mcp251x_can_probe(struct spi_device *spi)
 {
-	const void *match = device_get_match_data(&spi->dev);
 	struct net_device *net;
 	struct mcp251x_priv *priv;
 	struct clk *clk;
···
 	priv->can.clock.freq = freq / 2;
 	priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES |
 		CAN_CTRLMODE_LOOPBACK | CAN_CTRLMODE_LISTENONLY;
-	if (match)
-		priv->model = (enum mcp251x_model)(uintptr_t)match;
-	else
-		priv->model = spi_get_device_id(spi)->driver_data;
+	priv->model = (enum mcp251x_model)(uintptr_t)spi_get_device_match_data(spi);
 	priv->net = net;
 	priv->clk = clk;
 

drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c

···
 
 static int mcp251xfd_probe(struct spi_device *spi)
 {
-	const void *match;
 	struct net_device *ndev;
 	struct mcp251xfd_priv *priv;
 	struct gpio_desc *rx_int;
···
 	priv->pll_enable = pll_enable;
 	priv->reg_vdd = reg_vdd;
 	priv->reg_xceiver = reg_xceiver;
-
-	match = device_get_match_data(&spi->dev);
-	if (match)
-		priv->devtype_data = *(struct mcp251xfd_devtype_data *)match;
-	else
-		priv->devtype_data = *(struct mcp251xfd_devtype_data *)
-			spi_get_device_id(spi)->driver_data;
+	priv->devtype_data = *(struct mcp251xfd_devtype_data *)spi_get_device_match_data(spi);
 
 	/* Errata Reference:
 	 * mcp2517fd: DS80000792C 5., mcp2518fd: DS80000789C 4.

drivers/net/can/usb/Kconfig

···
 	    - Kvaser Leaf Light R v2
 	    - Kvaser Mini PCI Express HS
 	    - Kvaser Mini PCI Express 2xHS
+	    - Kvaser Mini PCIe 1xCAN
 	    - Kvaser USBcan Light 2xHS
 	    - Kvaser USBcan II HS/HS
 	    - Kvaser USBcan II HS/LS
···
 	    - Kvaser USBcan Light 4xHS
 	    - Kvaser USBcan Pro 2xHS v2
 	    - Kvaser USBcan Pro 4xHS
+	    - Kvaser USBcan Pro 5xCAN
 	    - Kvaser USBcan Pro 5xHS
 	    - Kvaser U100
 	    - Kvaser U100P
 	    - Kvaser U100S
 	    - ATI Memorator Pro 2xHS v2
 	    - ATI USBcan Pro 2xHS v2
+	    - Vining 800
 
 	  If unsure, say N.
 

drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c

···
 #define USB_HYBRID_CANLIN_PRODUCT_ID 0x0115
 #define USB_HYBRID_PRO_CANLIN_PRODUCT_ID 0x0116
 #define USB_LEAF_V3_PRODUCT_ID 0x0117
+#define USB_VINING_800_PRODUCT_ID 0x0119
+#define USB_USBCAN_PRO_5XCAN_PRODUCT_ID 0x011A
+#define USB_MINI_PCIE_1XCAN_PRODUCT_ID 0x011B
 
 static const struct kvaser_usb_driver_info kvaser_usb_driver_info_hydra = {
 	.quirks = KVASER_USB_QUIRK_HAS_HARDWARE_TIMESTAMP,
···
 	{ USB_DEVICE(KVASER_VENDOR_ID, USB_HYBRID_PRO_CANLIN_PRODUCT_ID),
 		.driver_info = (kernel_ulong_t)&kvaser_usb_driver_info_hydra },
 	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_V3_PRODUCT_ID),
+		.driver_info = (kernel_ulong_t)&kvaser_usb_driver_info_hydra },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_VINING_800_PRODUCT_ID),
+		.driver_info = (kernel_ulong_t)&kvaser_usb_driver_info_hydra },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_USBCAN_PRO_5XCAN_PRODUCT_ID),
+		.driver_info = (kernel_ulong_t)&kvaser_usb_driver_info_hydra },
+	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MINI_PCIE_1XCAN_PRODUCT_ID),
 		.driver_info = (kernel_ulong_t)&kvaser_usb_driver_info_hydra },
 	{ }
 };

drivers/net/can/xilinx_can.c

···
  * Copyright (C) 2017 - 2018 Sandvik Mining and Construction Oy
  *
  * Description:
- * This driver is developed for Axi CAN IP and for Zynq CANPS Controller.
+ * This driver is developed for AXI CAN IP, AXI CANFD IP, CANPS and CANFD PS Controller.
  */
 
 #include <linux/bitfield.h>

include/uapi/linux/can/isotp.h

···
 /*
  * linux/can/isotp.h
  *
- * Definitions for isotp CAN sockets (ISO 15765-2:2016)
+ * Definitions for ISO 15765-2 CAN transport protocol sockets
  *
  * Copyright (c) 2020 Volkswagen Group Electronic Research
  * All rights reserved.

net/can/Kconfig

···
 source "net/can/j1939/Kconfig"
 
 config CAN_ISOTP
-	tristate "ISO 15765-2:2016 CAN transport protocol"
+	tristate "ISO 15765-2 CAN transport protocol"
 	help
 	  CAN Transport Protocols offer support for segmented Point-to-Point
 	  communication between CAN nodes via two defined CAN Identifiers.
+	  This protocol driver implements segmented data transfers for CAN CC
+	  (aka Classical CAN, CAN 2.0B) and CAN FD frame types which were
+	  introduced with ISO 15765-2:2016.
 	  As CAN frames can only transport a small amount of data bytes
-	  (max. 8 bytes for 'classic' CAN and max. 64 bytes for CAN FD) this
+	  (max. 8 bytes for CAN CC and max. 64 bytes for CAN FD) this
 	  segmentation is needed to transport longer Protocol Data Units (PDU)
 	  as needed e.g. for vehicle diagnosis (UDS, ISO 14229) or IP-over-CAN
 	  traffic.
-	  This protocol driver implements data transfers according to
-	  ISO 15765-2:2016 for 'classic' CAN and CAN FD frame types.
-	  If you want to perform automotive vehicle diagnostic services (UDS),
-	  say 'y'.
 
 endif

net/can/isotp.c

···
 #include <net/sock.h>
 #include <net/net_namespace.h>
 
-MODULE_DESCRIPTION("PF_CAN isotp 15765-2:2016 protocol");
+MODULE_DESCRIPTION("PF_CAN ISO 15765-2 transport protocol");
 MODULE_LICENSE("Dual BSD/GPL");
 MODULE_AUTHOR("Oliver Hartkopp <[e-mail]>");
 MODULE_ALIAS("can-proto-6");
···
 			 (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \
 			 (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG))
 
-/* ISO 15765-2:2016 supports more than 4095 byte per ISO PDU as the FF_DL can
- * take full 32 bit values (4 Gbyte). We would need some good concept to handle
- * this between user space and kernel space. For now set the static buffer to
- * something about 8 kbyte to be able to test this new functionality.
+/* Since ISO 15765-2:2016 the CAN isotp protocol supports more than 4095
+ * byte per ISO PDU as the FF_DL can take full 32 bit values (4 Gbyte).
+ * We would need some good concept to handle this between user space and
+ * kernel space. For now set the static buffer to something about 8 kbyte
+ * to be able to test this new functionality.
  */
 #define DEFAULT_MAX_PDU_SIZE 8300