Merge tag 'linux-can-next-for-5.20-20220703' of...

Merge tag 'linux-can-next-for-5.20-20220703' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next

Marc Kleine-Budde says:

====================
pull-request: can-next 2022-07-03

this is a pull request of 15 patches for net-next/master.

The first 2 patches are by Max Staudt and add the can327 serial CAN
driver along with a new line discipline ID.

The next patch is by me an fixes a typo in the ctucanfd driver.

The last 12 patches are by Dario Binacchi and integrate slcan CAN
serial driver better into the existing CAN driver API.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/device_drivers/can/index.rst

@@ -10,6 +10,7 @@ Contents:
 .. toctree::
    :maxdepth: 2
 
+   can327
    ctu/ctucanfd-driver
    freescale/flexcan
 

MAINTAINERS

@@ -7320,6 +7320,13 @@ L:	netdev@vger.kernel.org
 S:	Maintained
 F:	drivers/net/ethernet/ibm/ehea/
 
+ELM327 CAN NETWORK DRIVER
+M:	Max Staudt <max@enpas.org>
+L:	linux-can@vger.kernel.org
+S:	Maintained
+F:	Documentation/networking/device_drivers/can/can327.rst
+F:	drivers/net/can/can327.c
+
 EM28XX VIDEO4LINUX DRIVER
 M:	Mauro Carvalho Chehab <mchehab@kernel.org>
 L:	linux-media@vger.kernel.org

drivers/net/can/Kconfig

@@ -49,26 +49,6 @@ config CAN_VXCAN
 	  This driver can also be built as a module.  If so, the module
 	  will be called vxcan.
 
-config CAN_SLCAN
-	tristate "Serial / USB serial CAN Adaptors (slcan)"
-	depends on TTY
-	help
-	  CAN driver for several 'low cost' CAN interfaces that are attached
-	  via serial lines or via USB-to-serial adapters using the LAWICEL
-	  ASCII protocol. The driver implements the tty linediscipline N_SLCAN.
-
-	  As only the sending and receiving of CAN frames is implemented, this
-	  driver should work with the (serial/USB) CAN hardware from:
-	  www.canusb.com / www.can232.com / www.mictronics.de / www.canhack.de
-
-	  Userspace tools to attach the SLCAN line discipline (slcan_attach,
-	  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.
-
 config CAN_NETLINK
 	bool "CAN device drivers with Netlink support"
 	default y
@@ -113,6 +93,24 @@ config CAN_AT91
 	  This is a driver for the SoC CAN controller in Atmel's AT91SAM9263
 	  and AT91SAM9X5 processors.
 
+config CAN_CAN327
+	tristate "Serial / USB serial ELM327 based OBD-II Interfaces (can327)"
+	depends on TTY
+	select CAN_RX_OFFLOAD
+	help
+	  CAN driver for several 'low cost' OBD-II interfaces based on the
+	  ELM327 OBD-II interpreter chip.
+
+	  This is a best effort driver - the ELM327 interface was never
+	  designed to be used as a standalone CAN interface. However, it can
+	  still be used for simple request-response protocols (such as OBD II),
+	  and to monitor broadcast messages on a bus (such as in a vehicle).
+
+	  Please refer to the documentation for information on how to use it:
+	  Documentation/networking/device_drivers/can/can327.rst
+
+	  If this driver is built as a module, it will be called can327.
+
 config CAN_FLEXCAN
 	tristate "Support for Freescale FLEXCAN based chips"
 	depends on OF || COLDFIRE || COMPILE_TEST
@@ -154,6 +152,26 @@ config CAN_KVASER_PCIEFD
 	    Kvaser Mini PCI Express HS v2
 	    Kvaser Mini PCI Express 2xHS v2
 
+config CAN_SLCAN
+	tristate "Serial / USB serial CAN Adaptors (slcan)"
+	depends on TTY
+	help
+	  CAN driver for several 'low cost' CAN interfaces that are attached
+	  via serial lines or via USB-to-serial adapters using the LAWICEL
+	  ASCII protocol. The driver implements the tty linediscipline N_SLCAN.
+
+	  As only the sending and receiving of CAN frames is implemented, this
+	  driver should work with the (serial/USB) CAN hardware from:
+	  www.canusb.com / www.can232.com / www.mictronics.de / www.canhack.de
+
+	  Userspace tools to attach the SLCAN line discipline (slcan_attach,
+	  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.
+
 config CAN_SUN4I
 	tristate "Allwinner A10 CAN controller"
 	depends on MACH_SUN4I || MACH_SUN7I || COMPILE_TEST

drivers/net/can/Makefile

@@ -5,7 +5,7 @@
 
 obj-$(CONFIG_CAN_VCAN)		+= vcan.o
 obj-$(CONFIG_CAN_VXCAN)		+= vxcan.o
-obj-$(CONFIG_CAN_SLCAN)		+= slcan.o
+obj-$(CONFIG_CAN_SLCAN)		+= slcan/
 
 obj-y				+= dev/
 obj-y				+= rcar/
@@ -14,6 +14,7 @@ obj-y				+= usb/
 obj-y				+= softing/
 
 obj-$(CONFIG_CAN_AT91)		+= at91_can.o
+obj-$(CONFIG_CAN_CAN327)	+= can327.o
 obj-$(CONFIG_CAN_CC770)		+= cc770/
 obj-$(CONFIG_CAN_C_CAN)		+= c_can/
 obj-$(CONFIG_CAN_CTUCANFD)	+= ctucanfd/

drivers/net/can/ctucanfd/ctucanfd_base.c

@@ -1087,7 +1087,7 @@ static void ctucan_tx_interrupt(struct net_device *ndev)
 /**
  * ctucan_interrupt() - CAN Isr
  * @irq:	irq number
- * @dev_id:	device id poniter
+ * @dev_id:	device id pointer
  *
  * This is the CTU CAN FD ISR. It checks for the type of interrupt
  * and invokes the corresponding ISR.

drivers/net/can/dev/netlink.c

@@ -511,7 +511,8 @@ static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
 	if (priv->do_get_state)
 		priv->do_get_state(dev, &state);
 
-	if ((priv->bittiming.bitrate &&
+	if ((priv->bittiming.bitrate != CAN_BITRATE_UNSET &&
+	     priv->bittiming.bitrate != CAN_BITRATE_UNKNOWN &&
 	     nla_put(skb, IFLA_CAN_BITTIMING,
 		     sizeof(priv->bittiming), &priv->bittiming)) ||
 

drivers/net/can/slcan/Makefile

+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_CAN_SLCAN) += slcan.o
+
+slcan-objs :=
+slcan-objs += slcan-core.o
+slcan-objs += slcan-ethtool.o

drivers/net/can/slcan/slcan-ethtool.c

+// SPDX-License-Identifier: GPL-2.0+
+/* Copyright (c) 2022 Amarula Solutions, Dario Binacchi <dario.binacchi@amarulasolutions.com>
+ *
+ */
+
+#include <linux/can/dev.h>
+#include <linux/ethtool.h>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/platform_device.h>
+
+#include "slcan.h"
+
+static const char slcan_priv_flags_strings[][ETH_GSTRING_LEN] = {
+#define SLCAN_PRIV_FLAGS_ERR_RST_ON_OPEN BIT(0)
+	"err-rst-on-open",
+};
+
+static void slcan_get_strings(struct net_device *ndev, u32 stringset, u8 *data)
+{
+	switch (stringset) {
+	case ETH_SS_PRIV_FLAGS:
+		memcpy(data, slcan_priv_flags_strings,
+		       sizeof(slcan_priv_flags_strings));
+	}
+}
+
+static u32 slcan_get_priv_flags(struct net_device *ndev)
+{
+	u32 flags = 0;
+
+	if (slcan_err_rst_on_open(ndev))
+		flags |= SLCAN_PRIV_FLAGS_ERR_RST_ON_OPEN;
+
+	return flags;
+}
+
+static int slcan_set_priv_flags(struct net_device *ndev, u32 flags)
+{
+	bool err_rst_op_open = !!(flags & SLCAN_PRIV_FLAGS_ERR_RST_ON_OPEN);
+
+	return slcan_enable_err_rst_on_open(ndev, err_rst_op_open);
+}
+
+static int slcan_get_sset_count(struct net_device *netdev, int sset)
+{
+	switch (sset) {
+	case ETH_SS_PRIV_FLAGS:
+		return ARRAY_SIZE(slcan_priv_flags_strings);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static const struct ethtool_ops slcan_ethtool_ops = {
+	.get_strings = slcan_get_strings,
+	.get_priv_flags = slcan_get_priv_flags,
+	.set_priv_flags = slcan_set_priv_flags,
+	.get_sset_count = slcan_get_sset_count,
+};
+
+void slcan_set_ethtool_ops(struct net_device *netdev)
+{
+	netdev->ethtool_ops = &slcan_ethtool_ops;
+}

drivers/net/can/slcan/slcan.h

+/* SPDX-License-Identifier: GPL-2.0
+ * slcan.h - serial line CAN interface driver
+ *
+ * Copyright (C) Laurence Culhane <loz@holmes.demon.co.uk>
+ * Copyright (C) Fred N. van Kempen <waltje@uwalt.nl.mugnet.org>
+ * Copyright (C) Oliver Hartkopp <socketcan@hartkopp.net>
+ * Copyright (C) 2022 Amarula Solutions, Dario Binacchi <dario.binacchi@amarulasolutions.com>
+ *
+ */
+
+#ifndef _SLCAN_H
+#define _SLCAN_H
+
+bool slcan_err_rst_on_open(struct net_device *ndev);
+int slcan_enable_err_rst_on_open(struct net_device *ndev, bool on);
+void slcan_set_ethtool_ops(struct net_device *ndev);
+
+#endif /* _SLCAN_H */

include/linux/can/bittiming.h

@@ -11,6 +11,8 @@
 
 #define CAN_SYNC_SEG 1
 
+#define CAN_BITRATE_UNSET 0
+#define CAN_BITRATE_UNKNOWN (-1U)
 
 #define CAN_CTRLMODE_TDC_MASK					\
 	(CAN_CTRLMODE_TDC_AUTO | CAN_CTRLMODE_TDC_MANUAL)

include/uapi/linux/tty.h

@@ -38,8 +38,9 @@
 #define N_NULL		27	/* Null ldisc used for error handling */
 #define N_MCTP		28	/* MCTP-over-serial */
 #define N_DEVELOPMENT	29	/* Manual out-of-tree testing */
+#define N_CAN327	30	/* ELM327 based OBD-II interfaces */
 
 /* Always the newest line discipline + 1 */
-#define NR_LDISCS	30
+#define NR_LDISCS	31
 
 #endif /* _UAPI_LINUX_TTY_H */