Merge branch 'for-davem' of git://gitorious.org/linux-can/linux-can-next

Marc Kleine-Budde says:

====================
this is a pull-request for net-next/master. There is are 9 patches by
Fabio Baltieri and Kurt Van Dijck which add LED infrastructure and
support for CAN devices. Bernd Krumboeck adds a driver for the USB CAN
adapter from 8 devices. Oliver Hartkopp improves the CAN gateway
functionality. There are 4 patches by me, which clean up the CAN's
Kconfig.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/can/Kconfig

 menu "CAN Device Drivers"
-	depends on CAN
 
 config CAN_VCAN
 	tristate "Virtual Local CAN Interface (vcan)"
-	depends on CAN
 	---help---
 	  Similar to the network loopback devices, vcan offers a
 	  virtual local CAN interface.
@@ -13,7 +11,6 @@ config CAN_VCAN
 
 config CAN_SLCAN
 	tristate "Serial / USB serial CAN Adaptors (slcan)"
-	depends on CAN
 	---help---
 	  CAN driver for several 'low cost' CAN interfaces that are attached
 	  via serial lines or via USB-to-serial adapters using the LAWICEL
@@ -33,16 +30,16 @@ config CAN_SLCAN
 
 config CAN_DEV
 	tristate "Platform CAN drivers with Netlink support"
-	depends on CAN
 	default y
 	---help---
 	  Enables the common framework for platform CAN drivers with Netlink
 	  support. This is the standard library for CAN drivers.
 	  If unsure, say Y.
 
+if CAN_DEV
+
 config CAN_CALC_BITTIMING
 	bool "CAN bit-timing calculation"
-	depends on CAN_DEV
 	default y
 	---help---
 	  If enabled, CAN bit-timing parameters will be calculated for the
@@ -54,15 +51,26 @@ config CAN_CALC_BITTIMING
 	  arguments "tq", "prop_seg", "phase_seg1", "phase_seg2" and "sjw".
 	  If unsure, say Y.
 
+config CAN_LEDS
+	bool "Enable LED triggers for Netlink based drivers"
+	depends on LEDS_CLASS
+	select LEDS_TRIGGERS
+	---help---
+	  This option adds two LED triggers for packet receive and transmit
+	  events on each supported CAN device.
+
+	  Say Y here if you are working on a system with led-class supported
+	  LEDs and you want to use them as canbus activity indicators.
+
 config CAN_AT91
 	tristate "Atmel AT91 onchip CAN controller"
-	depends on CAN_DEV && (ARCH_AT91SAM9263 || ARCH_AT91SAM9X5)
+	depends on ARCH_AT91SAM9263 || ARCH_AT91SAM9X5
 	---help---
 	  This is a driver for the SoC CAN controller in Atmel's AT91SAM9263
 	  and AT91SAM9X5 processors.
 
 config CAN_TI_HECC
-	depends on CAN_DEV && ARCH_OMAP3
+	depends on ARCH_OMAP3
 	tristate "TI High End CAN Controller"
 	---help---
 	  Driver for TI HECC (High End CAN Controller) module found on many
@@ -70,12 +78,12 @@ config CAN_TI_HECC
 
 config CAN_MCP251X
 	tristate "Microchip MCP251x SPI CAN controllers"
-	depends on CAN_DEV && SPI && HAS_DMA
+	depends on SPI && HAS_DMA
 	---help---
 	  Driver for the Microchip MCP251x SPI CAN controllers.
 
 config CAN_BFIN
-	depends on CAN_DEV && (BF534 || BF536 || BF537 || BF538 || BF539 || BF54x)
+	depends on BF534 || BF536 || BF537 || BF538 || BF539 || BF54x
 	tristate "Analog Devices Blackfin on-chip CAN"
 	---help---
 	  Driver for the Analog Devices Blackfin on-chip CAN controllers
@@ -85,7 +93,7 @@ config CAN_BFIN
 
 config CAN_JANZ_ICAN3
 	tristate "Janz VMOD-ICAN3 Intelligent CAN controller"
-	depends on CAN_DEV && MFD_JANZ_CMODIO
+	depends on MFD_JANZ_CMODIO
 	---help---
 	  Driver for Janz VMOD-ICAN3 Intelligent CAN controller module, which
 	  connects to a MODULbus carrier board.
@@ -98,13 +106,13 @@ config HAVE_CAN_FLEXCAN
 
 config CAN_FLEXCAN
 	tristate "Support for Freescale FLEXCAN based chips"
-	depends on CAN_DEV && HAVE_CAN_FLEXCAN
+	depends on HAVE_CAN_FLEXCAN
 	---help---
 	  Say Y here if you want to support for Freescale FlexCAN.
 
 config PCH_CAN
 	tristate "Intel EG20T PCH CAN controller"
-	depends on CAN_DEV && PCI
+	depends on PCI
 	---help---
 	  This driver is for PCH CAN of Topcliff (Intel EG20T PCH) which
 	  is an IOH for x86 embedded processor (Intel Atom E6xx series).
@@ -112,7 +120,7 @@ config PCH_CAN
 
 config CAN_GRCAN
 	tristate "Aeroflex Gaisler GRCAN and GRHCAN CAN devices"
-	depends on CAN_DEV && OF
+	depends on OF
 	---help---
 	  Say Y here if you want to use Aeroflex Gaisler GRCAN or GRHCAN.
 	  Note that the driver supports little endian, even though little
@@ -131,9 +139,10 @@ source "drivers/net/can/usb/Kconfig"
 
 source "drivers/net/can/softing/Kconfig"
 
+endif
+
 config CAN_DEBUG_DEVICES
 	bool "CAN devices debugging messages"
-	depends on CAN
 	---help---
 	  Say Y here if you want the CAN device drivers to produce a bunch of
 	  debug messages to the system log.  Select this if you are having

drivers/net/can/Makefile

@@ -8,6 +8,8 @@ obj-$(CONFIG_CAN_SLCAN)		+= slcan.o
 obj-$(CONFIG_CAN_DEV)		+= can-dev.o
 can-dev-y			:= dev.o
 
+can-dev-$(CONFIG_CAN_LEDS)	+= led.o
+
 obj-y				+= usb/
 obj-y				+= softing/
 

drivers/net/can/at91_can.c

@@ -37,6 +37,7 @@
 
 #include <linux/can/dev.h>
 #include <linux/can/error.h>
+#include <linux/can/led.h>
 
 #define AT91_MB_MASK(i)		((1 << (i)) - 1)
 
@@ -641,6 +642,8 @@ static void at91_read_msg(struct net_device *dev, unsigned int mb)
 
 	stats->rx_packets++;
 	stats->rx_bytes += cf->can_dlc;
+
+	can_led_event(dev, CAN_LED_EVENT_RX);
 }
 
 /**
@@ -875,6 +878,7 @@ static void at91_irq_tx(struct net_device *dev, u32 reg_sr)
 			/* _NOTE_: subtract AT91_MB_TX_FIRST offset from mb! */
 			can_get_echo_skb(dev, mb - get_mb_tx_first(priv));
 			dev->stats.tx_packets++;
+			can_led_event(dev, CAN_LED_EVENT_TX);
 		}
 	}
 
@@ -1128,6 +1132,8 @@ static int at91_open(struct net_device *dev)
 		goto out_close;
 	}
 
+	can_led_event(dev, CAN_LED_EVENT_OPEN);
+
 	/* start chip and queuing */
 	at91_chip_start(dev);
 	napi_enable(&priv->napi);
@@ -1159,6 +1165,8 @@ static int at91_close(struct net_device *dev)
 
 	close_candev(dev);
 
+	can_led_event(dev, CAN_LED_EVENT_STOP);
+
 	return 0;
 }
 
@@ -1321,6 +1329,8 @@ static int at91_can_probe(struct platform_device *pdev)
 		goto exit_free;
 	}
 
+	devm_can_led_init(dev);
+
 	dev_info(&pdev->dev, "device registered (reg_base=%p, irq=%d)\n",
 		 priv->reg_base, dev->irq);
 

drivers/net/can/c_can/Kconfig

 menuconfig CAN_C_CAN
 	tristate "Bosch C_CAN/D_CAN devices"
-	depends on CAN_DEV && HAS_IOMEM
+	depends on HAS_IOMEM
 
 if CAN_C_CAN
 

drivers/net/can/c_can/c_can.c

@@ -39,6 +39,7 @@
 #include <linux/can.h>
 #include <linux/can/dev.h>
 #include <linux/can/error.h>
+#include <linux/can/led.h>
 
 #include "c_can.h"
 
@@ -477,6 +478,8 @@ static int c_can_read_msg_object(struct net_device *dev, int iface, int ctrl)
 	stats->rx_packets++;
 	stats->rx_bytes += frame->can_dlc;
 
+	can_led_event(dev, CAN_LED_EVENT_RX);
+
 	return 0;
 }
 
@@ -751,6 +754,7 @@ static void c_can_do_tx(struct net_device *dev)
 					C_CAN_IFACE(MSGCTRL_REG, 0))
 					& IF_MCONT_DLC_MASK;
 			stats->tx_packets++;
+			can_led_event(dev, CAN_LED_EVENT_TX);
 			c_can_inval_msg_object(dev, 0, msg_obj_no);
 		} else {
 			break;
@@ -1115,6 +1119,8 @@ static int c_can_open(struct net_device *dev)
 
 	napi_enable(&priv->napi);
 
+	can_led_event(dev, CAN_LED_EVENT_OPEN);
+
 	/* start the c_can controller */
 	c_can_start(dev);
 
@@ -1143,6 +1149,8 @@ static int c_can_close(struct net_device *dev)
 	c_can_reset_ram(priv, false);
 	c_can_pm_runtime_put_sync(priv);
 
+	can_led_event(dev, CAN_LED_EVENT_STOP);
+
 	return 0;
 }
 
@@ -1268,6 +1276,8 @@ int register_c_can_dev(struct net_device *dev)
 	err = register_candev(dev);
 	if (err)
 		c_can_pm_runtime_disable(priv);
+	else
+		devm_can_led_init(dev);
 
 	return err;
 }

drivers/net/can/cc770/Kconfig

 menuconfig CAN_CC770
 	tristate "Bosch CC770 and Intel AN82527 devices"
-	depends on CAN_DEV && HAS_IOMEM
+	depends on HAS_IOMEM
 
 if CAN_CC770
 

drivers/net/can/dev.c

@@ -24,7 +24,9 @@
 #include <linux/if_arp.h>
 #include <linux/can.h>
 #include <linux/can/dev.h>
+#include <linux/can/skb.h>
 #include <linux/can/netlink.h>
+#include <linux/can/led.h>
 #include <net/rtnetlink.h>
 
 #define MOD_DESC "CAN device driver interface"
@@ -501,13 +503,18 @@ struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
 {
 	struct sk_buff *skb;
 
-	skb = netdev_alloc_skb(dev, sizeof(struct can_frame));
+	skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +
+			       sizeof(struct can_frame));
 	if (unlikely(!skb))
 		return NULL;
 
 	skb->protocol = htons(ETH_P_CAN);
 	skb->pkt_type = PACKET_BROADCAST;
 	skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+	skb_reserve(skb, sizeof(struct can_skb_priv));
+	((struct can_skb_priv *)(skb->head))->ifindex = dev->ifindex;
+
 	*cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
 	memset(*cf, 0, sizeof(struct can_frame));
 
@@ -794,10 +801,25 @@ void unregister_candev(struct net_device *dev)
 }
 EXPORT_SYMBOL_GPL(unregister_candev);
 
+/*
+ * Test if a network device is a candev based device
+ * and return the can_priv* if so.
+ */
+struct can_priv *safe_candev_priv(struct net_device *dev)
+{
+	if ((dev->type != ARPHRD_CAN) || (dev->rtnl_link_ops != &can_link_ops))
+		return NULL;
+
+	return netdev_priv(dev);
+}
+EXPORT_SYMBOL_GPL(safe_candev_priv);
+
 static __init int can_dev_init(void)
 {
 	int err;
 
+	can_led_notifier_init();
+
 	err = rtnl_link_register(&can_link_ops);
 	if (!err)
 		printk(KERN_INFO MOD_DESC "\n");
@@ -809,6 +831,8 @@ module_init(can_dev_init);
 static __exit void can_dev_exit(void)
 {
 	rtnl_link_unregister(&can_link_ops);
+
+	can_led_notifier_exit();
 }
 module_exit(can_dev_exit);
 

drivers/net/can/flexcan.c

@@ -23,6 +23,7 @@
 #include <linux/can.h>
 #include <linux/can/dev.h>
 #include <linux/can/error.h>
+#include <linux/can/led.h>
 #include <linux/can/platform/flexcan.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
@@ -564,6 +565,8 @@ static int flexcan_read_frame(struct net_device *dev)
 	stats->rx_packets++;
 	stats->rx_bytes += cf->can_dlc;
 
+	can_led_event(dev, CAN_LED_EVENT_RX);
+
 	return 1;
 }
 
@@ -652,6 +655,7 @@ static irqreturn_t flexcan_irq(int irq, void *dev_id)
 	if (reg_iflag1 & (1 << FLEXCAN_TX_BUF_ID)) {
 		stats->tx_bytes += can_get_echo_skb(dev, 0);
 		stats->tx_packets++;
+		can_led_event(dev, CAN_LED_EVENT_TX);
 		flexcan_write((1 << FLEXCAN_TX_BUF_ID), &regs->iflag1);
 		netif_wake_queue(dev);
 	}
@@ -865,6 +869,9 @@ static int flexcan_open(struct net_device *dev)
 	err = flexcan_chip_start(dev);
 	if (err)
 		goto out_close;
+
+	can_led_event(dev, CAN_LED_EVENT_OPEN);
+
 	napi_enable(&priv->napi);
 	netif_start_queue(dev);
 
@@ -893,6 +900,8 @@ static int flexcan_close(struct net_device *dev)
 
 	close_candev(dev);
 
+	can_led_event(dev, CAN_LED_EVENT_STOP);
+
 	return 0;
 }
 
@@ -1092,6 +1101,8 @@ static int flexcan_probe(struct platform_device *pdev)
 		goto failed_register;
 	}
 
+	devm_can_led_init(dev);
+
 	dev_info(&pdev->dev, "device registered (reg_base=%p, irq=%d)\n",
 		 priv->base, dev->irq);
 

drivers/net/can/led.c

+/*
+ * Copyright 2012, Fabio Baltieri <fabio.baltieri@gmail.com>
+ * Copyright 2012, Kurt Van Dijck <kurt.van.dijck@eia.be>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/netdevice.h>
+#include <linux/can/dev.h>
+
+#include <linux/can/led.h>
+
+static unsigned long led_delay = 50;
+module_param(led_delay, ulong, 0644);
+MODULE_PARM_DESC(led_delay,
+		"blink delay time for activity leds (msecs, default: 50).");
+
+/* Trigger a LED event in response to a CAN device event */
+void can_led_event(struct net_device *netdev, enum can_led_event event)
+{
+	struct can_priv *priv = netdev_priv(netdev);
+
+	switch (event) {
+	case CAN_LED_EVENT_OPEN:
+		led_trigger_event(priv->tx_led_trig, LED_FULL);
+		led_trigger_event(priv->rx_led_trig, LED_FULL);
+		break;
+	case CAN_LED_EVENT_STOP:
+		led_trigger_event(priv->tx_led_trig, LED_OFF);
+		led_trigger_event(priv->rx_led_trig, LED_OFF);
+		break;
+	case CAN_LED_EVENT_TX:
+		if (led_delay)
+			led_trigger_blink_oneshot(priv->tx_led_trig,
+						  &led_delay, &led_delay, 1);
+		break;
+	case CAN_LED_EVENT_RX:
+		if (led_delay)
+			led_trigger_blink_oneshot(priv->rx_led_trig,
+						  &led_delay, &led_delay, 1);
+		break;
+	}
+}
+EXPORT_SYMBOL_GPL(can_led_event);
+
+static void can_led_release(struct device *gendev, void *res)
+{
+	struct can_priv *priv = netdev_priv(to_net_dev(gendev));
+
+	led_trigger_unregister_simple(priv->tx_led_trig);
+	led_trigger_unregister_simple(priv->rx_led_trig);
+}
+
+/* Register CAN LED triggers for a CAN device
+ *
+ * This is normally called from a driver's probe function
+ */
+void devm_can_led_init(struct net_device *netdev)
+{
+	struct can_priv *priv = netdev_priv(netdev);
+	void *res;
+
+	res = devres_alloc(can_led_release, 0, GFP_KERNEL);
+	if (!res) {
+		netdev_err(netdev, "cannot register LED triggers\n");
+		return;
+	}
+
+	snprintf(priv->tx_led_trig_name, sizeof(priv->tx_led_trig_name),
+		 "%s-tx", netdev->name);
+	snprintf(priv->rx_led_trig_name, sizeof(priv->rx_led_trig_name),
+		 "%s-rx", netdev->name);
+
+	led_trigger_register_simple(priv->tx_led_trig_name,
+				    &priv->tx_led_trig);
+	led_trigger_register_simple(priv->rx_led_trig_name,
+				    &priv->rx_led_trig);
+
+	devres_add(&netdev->dev, res);
+}
+EXPORT_SYMBOL_GPL(devm_can_led_init);
+
+/* NETDEV rename notifier to rename the associated led triggers too */
+static int can_led_notifier(struct notifier_block *nb, unsigned long msg,
+			void *data)
+{
+	struct net_device *netdev = data;
+	struct can_priv *priv = safe_candev_priv(netdev);
+	char name[CAN_LED_NAME_SZ];
+
+	if (!priv)
+		return NOTIFY_DONE;
+
+	if (msg == NETDEV_CHANGENAME) {
+		snprintf(name, sizeof(name), "%s-tx", netdev->name);
+		led_trigger_rename_static(name, priv->tx_led_trig);
+
+		snprintf(name, sizeof(name), "%s-rx", netdev->name);
+		led_trigger_rename_static(name, priv->rx_led_trig);
+	}
+
+	return NOTIFY_DONE;
+}
+
+/* notifier block for netdevice event */
+static struct notifier_block can_netdev_notifier __read_mostly = {
+	.notifier_call = can_led_notifier,
+};
+
+int __init can_led_notifier_init(void)
+{
+	return register_netdevice_notifier(&can_netdev_notifier);
+}
+
+void __exit can_led_notifier_exit(void)
+{
+	unregister_netdevice_notifier(&can_netdev_notifier);
+}

drivers/net/can/mcp251x.c

@@ -60,6 +60,7 @@
 
 #include <linux/can/core.h>
 #include <linux/can/dev.h>
+#include <linux/can/led.h>
 #include <linux/can/platform/mcp251x.h>
 #include <linux/completion.h>
 #include <linux/delay.h>
@@ -494,6 +495,9 @@ static void mcp251x_hw_rx(struct spi_device *spi, int buf_idx)
 
 	priv->net->stats.rx_packets++;
 	priv->net->stats.rx_bytes += frame->can_dlc;
+
+	can_led_event(priv->net, CAN_LED_EVENT_RX);
+
 	netif_rx_ni(skb);
 }
 
@@ -707,6 +711,8 @@ static int mcp251x_stop(struct net_device *net)
 
 	mutex_unlock(&priv->mcp_lock);
 
+	can_led_event(net, CAN_LED_EVENT_STOP);
+
 	return 0;
 }
 
@@ -905,6 +911,7 @@ static irqreturn_t mcp251x_can_ist(int irq, void *dev_id)
 		if (intf & CANINTF_TX) {
 			net->stats.tx_packets++;
 			net->stats.tx_bytes += priv->tx_len - 1;
+			can_led_event(net, CAN_LED_EVENT_TX);
 			if (priv->tx_len) {
 				can_get_echo_skb(net, 0);
 				priv->tx_len = 0;
@@ -968,6 +975,9 @@ static int mcp251x_open(struct net_device *net)
 		mcp251x_open_clean(net);
 		goto open_unlock;
 	}
+
+	can_led_event(net, CAN_LED_EVENT_OPEN);
+
 	netif_wake_queue(net);
 
 open_unlock:
@@ -1077,10 +1087,15 @@ static int mcp251x_can_probe(struct spi_device *spi)
 		pdata->transceiver_enable(0);
 
 	ret = register_candev(net);
-	if (!ret) {
+	if (ret)
+		goto error_probe;
+
+	devm_can_led_init(net);
+
 	dev_info(&spi->dev, "probed\n");
+
 	return ret;
-	}
+
 error_probe:
 	if (!mcp251x_enable_dma)
 		kfree(priv->spi_rx_buf);

drivers/net/can/mscan/Kconfig

 config CAN_MSCAN
-	depends on CAN_DEV && (PPC || M68K)
+	depends on PPC || M68K
 	tristate "Support for Freescale MSCAN based chips"
 	---help---
 	  The Motorola Scalable Controller Area Network (MSCAN) definition

drivers/net/can/sja1000/Kconfig

 menuconfig CAN_SJA1000
 	tristate "Philips/NXP SJA1000 devices"
-	depends on CAN_DEV && HAS_IOMEM
+	depends on HAS_IOMEM
 
 if CAN_SJA1000
 

drivers/net/can/sja1000/sja1000.c

@@ -60,6 +60,7 @@
 
 #include <linux/can/dev.h>
 #include <linux/can/error.h>
+#include <linux/can/led.h>
 
 #include "sja1000.h"
 
@@ -368,6 +369,8 @@ static void sja1000_rx(struct net_device *dev)
 
 	stats->rx_packets++;
 	stats->rx_bytes += cf->can_dlc;
+
+	can_led_event(dev, CAN_LED_EVENT_RX);
 }
 
 static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status)
@@ -521,6 +524,7 @@ irqreturn_t sja1000_interrupt(int irq, void *dev_id)
 				can_get_echo_skb(dev, 0);
 			}
 			netif_wake_queue(dev);
+			can_led_event(dev, CAN_LED_EVENT_TX);
 		}
 		if (isrc & IRQ_RI) {
 			/* receive interrupt */
@@ -575,6 +579,8 @@ static int sja1000_open(struct net_device *dev)
 	/* init and start chi */
 	sja1000_start(dev);
 
+	can_led_event(dev, CAN_LED_EVENT_OPEN);
+
 	netif_start_queue(dev);
 
 	return 0;
@@ -592,6 +598,8 @@ static int sja1000_close(struct net_device *dev)
 
 	close_candev(dev);
 
+	can_led_event(dev, CAN_LED_EVENT_STOP);
+
 	return 0;
 }
 
@@ -639,6 +647,8 @@ static const struct net_device_ops sja1000_netdev_ops = {
 
 int register_sja1000dev(struct net_device *dev)
 {
+	int ret;
+
 	if (!sja1000_probe_chip(dev))
 		return -ENODEV;
 
@@ -648,7 +658,12 @@ int register_sja1000dev(struct net_device *dev)
 	set_reset_mode(dev);
 	chipset_init(dev);
 
-	return register_candev(dev);
+	ret =  register_candev(dev);
+
+	if (!ret)
+		devm_can_led_init(dev);
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(register_sja1000dev);
 

drivers/net/can/slcan.c

@@ -55,6 +55,7 @@
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/can.h>
+#include <linux/can/skb.h>
 
 static __initconst const char banner[] =
 	KERN_INFO "slcan: serial line CAN interface driver\n";
@@ -184,7 +185,8 @@ static void slc_bump(struct slcan *sl)
 		cf.data[i] |= tmp;
 	}
 
-	skb = dev_alloc_skb(sizeof(struct can_frame));
+	skb = dev_alloc_skb(sizeof(struct can_frame) +
+			    sizeof(struct can_skb_priv));
 	if (!skb)
 		return;
 
@@ -192,6 +194,10 @@ static void slc_bump(struct slcan *sl)
 	skb->protocol = htons(ETH_P_CAN);
 	skb->pkt_type = PACKET_BROADCAST;
 	skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+	skb_reserve(skb, sizeof(struct can_skb_priv));
+	((struct can_skb_priv *)(skb->head))->ifindex = sl->dev->ifindex;
+
 	memcpy(skb_put(skb, sizeof(struct can_frame)),
 	       &cf, sizeof(struct can_frame));
 	netif_rx_ni(skb);

drivers/net/can/softing/Kconfig

 config CAN_SOFTING
 	tristate "Softing Gmbh CAN generic support"
-	depends on CAN_DEV && HAS_IOMEM
+	depends on HAS_IOMEM
 	---help---
 	  Support for CAN cards from Softing Gmbh & some cards
 	  from Vector Gmbh.

drivers/net/can/ti_hecc.c

@@ -50,6 +50,7 @@
 
 #include <linux/can/dev.h>
 #include <linux/can/error.h>
+#include <linux/can/led.h>
 #include <linux/can/platform/ti_hecc.h>
 
 #define DRV_NAME "ti_hecc"
@@ -593,6 +594,7 @@ static int ti_hecc_rx_pkt(struct ti_hecc_priv *priv, int mbxno)
 	spin_unlock_irqrestore(&priv->mbx_lock, flags);
 
 	stats->rx_bytes += cf->can_dlc;
+	can_led_event(priv->ndev, CAN_LED_EVENT_RX);
 	netif_receive_skb(skb);
 	stats->rx_packets++;
 
@@ -796,6 +798,7 @@ static irqreturn_t ti_hecc_interrupt(int irq, void *dev_id)
 			stats->tx_bytes += hecc_read_mbx(priv, mbxno,
 						HECC_CANMCF) & 0xF;
 			stats->tx_packets++;
+			can_led_event(ndev, CAN_LED_EVENT_TX);
 			can_get_echo_skb(ndev, mbxno);
 			--priv->tx_tail;
 		}
@@ -851,6 +854,8 @@ static int ti_hecc_open(struct net_device *ndev)
 		return err;
 	}
 
+	can_led_event(ndev, CAN_LED_EVENT_OPEN);
+
 	ti_hecc_start(ndev);
 	napi_enable(&priv->napi);
 	netif_start_queue(ndev);
@@ -869,6 +874,8 @@ static int ti_hecc_close(struct net_device *ndev)
 	close_candev(ndev);
 	ti_hecc_transceiver_switch(priv, 0);
 
+	can_led_event(ndev, CAN_LED_EVENT_STOP);
+
 	return 0;
 }
 
@@ -961,6 +968,9 @@ static int ti_hecc_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "register_candev() failed\n");
 		goto probe_exit_clk;
 	}
+
+	devm_can_led_init(ndev);
+
 	dev_info(&pdev->dev, "device registered (reg_base=%p, irq=%u)\n",
 		priv->base, (u32) ndev->irq);
 

drivers/net/can/usb/Kconfig

 menu "CAN USB interfaces"
-	depends on USB && CAN_DEV
+	depends on USB
 
 config CAN_EMS_USB
 	tristate "EMS CPC-USB/ARM7 CAN/USB interface"
@@ -48,4 +48,10 @@ config CAN_PEAK_USB
 	  This driver supports the PCAN-USB and PCAN-USB Pro adapters
 	  from PEAK-System Technik (http://www.peak-system.com).
 
+config CAN_8DEV_USB
+	tristate "8 devices USB2CAN interface"
+	---help---
+	  This driver supports the USB2CAN interface
+	  from 8 devices (http://www.8devices.com).
+
 endmenu

drivers/net/can/usb/Makefile

@@ -6,5 +6,6 @@ obj-$(CONFIG_CAN_EMS_USB) += ems_usb.o
 obj-$(CONFIG_CAN_ESD_USB2) += esd_usb2.o
 obj-$(CONFIG_CAN_KVASER_USB) += kvaser_usb.o
 obj-$(CONFIG_CAN_PEAK_USB) += peak_usb/
+obj-$(CONFIG_CAN_8DEV_USB) += usb_8dev.o
 
 ccflags-$(CONFIG_CAN_DEBUG_DEVICES) := -DDEBUG

drivers/net/can/usb/usb_8dev.c

+/*
+ * CAN driver for "8 devices" USB2CAN converter
+ *
+ * Copyright (C) 2012 Bernd Krumboeck (krumboeck@universalnet.at)
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; version 2 of the License.
+ *
+ * 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.
+ *
+ * This driver is inspired by the 3.2.0 version of drivers/net/can/usb/ems_usb.c
+ * and drivers/net/can/usb/esd_usb2.c
+ *
+ * Many thanks to Gerhard Bertelsmann (info@gerhard-bertelsmann.de)
+ * for testing and fixing this driver. Also many thanks to "8 devices",
+ * who were very cooperative and answered my questions.
+ */
+
+#include <linux/init.h>
+#include <linux/signal.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/usb.h>
+
+#include <linux/can.h>
+#include <linux/can/dev.h>
+#include <linux/can/error.h>
+#include <linux/can/led.h>
+
+/* driver constants */
+#define MAX_RX_URBS			20
+#define MAX_TX_URBS			20
+#define RX_BUFFER_SIZE			64
+
+/* vendor and product id */
+#define USB_8DEV_VENDOR_ID		0x0483
+#define USB_8DEV_PRODUCT_ID		0x1234
+
+/* endpoints */
+enum usb_8dev_endpoint {
+	USB_8DEV_ENDP_DATA_RX = 1,
+	USB_8DEV_ENDP_DATA_TX,
+	USB_8DEV_ENDP_CMD_RX,
+	USB_8DEV_ENDP_CMD_TX
+};
+
+/* device CAN clock */
+#define USB_8DEV_ABP_CLOCK		32000000
+
+/* setup flags */
+#define USB_8DEV_SILENT			0x01
+#define USB_8DEV_LOOPBACK		0x02
+#define USB_8DEV_DISABLE_AUTO_RESTRANS	0x04
+#define USB_8DEV_STATUS_FRAME		0x08
+
+/* commands */
+enum usb_8dev_cmd {
+	USB_8DEV_RESET = 1,
+	USB_8DEV_OPEN,
+	USB_8DEV_CLOSE,
+	USB_8DEV_SET_SPEED,
+	USB_8DEV_SET_MASK_FILTER,
+	USB_8DEV_GET_STATUS,
+	USB_8DEV_GET_STATISTICS,
+	USB_8DEV_GET_SERIAL,
+	USB_8DEV_GET_SOFTW_VER,
+	USB_8DEV_GET_HARDW_VER,
+	USB_8DEV_RESET_TIMESTAMP,
+	USB_8DEV_GET_SOFTW_HARDW_VER
+};
+
+/* command options */
+#define USB_8DEV_BAUD_MANUAL		0x09
+#define USB_8DEV_CMD_START		0x11
+#define USB_8DEV_CMD_END		0x22
+
+#define USB_8DEV_CMD_SUCCESS		0
+#define USB_8DEV_CMD_ERROR		255
+
+#define USB_8DEV_CMD_TIMEOUT		1000
+
+/* frames */
+#define USB_8DEV_DATA_START		0x55
+#define USB_8DEV_DATA_END		0xAA
+
+#define USB_8DEV_TYPE_CAN_FRAME		0
+#define USB_8DEV_TYPE_ERROR_FRAME	3
+
+#define USB_8DEV_EXTID			0x01
+#define USB_8DEV_RTR			0x02
+#define USB_8DEV_ERR_FLAG		0x04
+
+/* status */
+#define USB_8DEV_STATUSMSG_OK		0x00  /* Normal condition. */
+#define USB_8DEV_STATUSMSG_OVERRUN	0x01  /* Overrun occured when sending */
+#define USB_8DEV_STATUSMSG_BUSLIGHT	0x02  /* Error counter has reached 96 */
+#define USB_8DEV_STATUSMSG_BUSHEAVY	0x03  /* Error count. has reached 128 */
+#define USB_8DEV_STATUSMSG_BUSOFF	0x04  /* Device is in BUSOFF */
+#define USB_8DEV_STATUSMSG_STUFF	0x20  /* Stuff Error */
+#define USB_8DEV_STATUSMSG_FORM		0x21  /* Form Error */
+#define USB_8DEV_STATUSMSG_ACK		0x23  /* Ack Error */
+#define USB_8DEV_STATUSMSG_BIT0		0x24  /* Bit1 Error */
+#define USB_8DEV_STATUSMSG_BIT1		0x25  /* Bit0 Error */
+#define USB_8DEV_STATUSMSG_CRC		0x27  /* CRC Error */
+
+#define USB_8DEV_RP_MASK		0x7F  /* Mask for Receive Error Bit */
+
+
+/* table of devices that work with this driver */
+static const struct usb_device_id usb_8dev_table[] = {
+	{ USB_DEVICE(USB_8DEV_VENDOR_ID, USB_8DEV_PRODUCT_ID) },
+	{ }					/* Terminating entry */
+};
+
+MODULE_DEVICE_TABLE(usb, usb_8dev_table);
+
+struct usb_8dev_tx_urb_context {
+	struct usb_8dev_priv *priv;
+
+	u32 echo_index;
+	u8 dlc;
+};
+
+/* Structure to hold all of our device specific stuff */
+struct usb_8dev_priv {
+	struct can_priv can; /* must be the first member */
+
+	struct sk_buff *echo_skb[MAX_TX_URBS];
+
+	struct usb_device *udev;
+	struct net_device *netdev;
+
+	atomic_t active_tx_urbs;
+	struct usb_anchor tx_submitted;
+	struct usb_8dev_tx_urb_context tx_contexts[MAX_TX_URBS];
+
+	struct usb_anchor rx_submitted;
+
+	struct can_berr_counter bec;
+
+	u8 *cmd_msg_buffer;
+
+	struct mutex usb_8dev_cmd_lock;
+
+};
+
+/* tx frame */
+struct __packed usb_8dev_tx_msg {
+	u8 begin;
+	u8 flags;	/* RTR and EXT_ID flag */
+	__be32 id;	/* upper 3 bits not used */
+	u8 dlc;		/* data length code 0-8 bytes */
+	u8 data[8];	/* 64-bit data */
+	u8 end;
+};
+
+/* rx frame */
+struct __packed usb_8dev_rx_msg {
+	u8 begin;
+	u8 type;		/* frame type */
+	u8 flags;		/* RTR and EXT_ID flag */
+	__be32 id;		/* upper 3 bits not used */
+	u8 dlc;			/* data length code 0-8 bytes */
+	u8 data[8];		/* 64-bit data */
+	__be32 timestamp;	/* 32-bit timestamp */
+	u8 end;
+};
+
+/* command frame */
+struct __packed usb_8dev_cmd_msg {
+	u8 begin;
+	u8 channel;	/* unkown - always 0 */
+	u8 command;	/* command to execute */
+	u8 opt1;	/* optional parameter / return value */
+	u8 opt2;	/* optional parameter 2 */
+	u8 data[10];	/* optional parameter and data */
+	u8 end;
+};
+
+static int usb_8dev_send_cmd_msg(struct usb_8dev_priv *priv, u8 *msg, int size)
+{
+	int actual_length;
+
+	return usb_bulk_msg(priv->udev,
+			    usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_CMD_TX),
+			    msg, size, &actual_length, USB_8DEV_CMD_TIMEOUT);
+}
+
+static int usb_8dev_wait_cmd_msg(struct usb_8dev_priv *priv, u8 *msg, int size,
+				int *actual_length)
+{
+	return usb_bulk_msg(priv->udev,
+			    usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_CMD_RX),
+			    msg, size, actual_length, USB_8DEV_CMD_TIMEOUT);
+}
+
+/* Send command to device and receive result.
+ * Command was successful when opt1 = 0.
+ */
+static int usb_8dev_send_cmd(struct usb_8dev_priv *priv,
+			     struct usb_8dev_cmd_msg *out,
+			     struct usb_8dev_cmd_msg *in)
+{
+	int err;
+	int num_bytes_read;
+	struct net_device *netdev;
+
+	netdev = priv->netdev;
+
+	out->begin = USB_8DEV_CMD_START;
+	out->end = USB_8DEV_CMD_END;
+
+	mutex_lock(&priv->usb_8dev_cmd_lock);
+
+	memcpy(priv->cmd_msg_buffer, out,
+		sizeof(struct usb_8dev_cmd_msg));
+
+	err = usb_8dev_send_cmd_msg(priv, priv->cmd_msg_buffer,
+				    sizeof(struct usb_8dev_cmd_msg));
+	if (err < 0) {
+		netdev_err(netdev, "sending command message failed\n");
+		goto failed;
+	}
+
+	err = usb_8dev_wait_cmd_msg(priv, priv->cmd_msg_buffer,
+				    sizeof(struct usb_8dev_cmd_msg),
+				    &num_bytes_read);
+	if (err < 0) {
+		netdev_err(netdev, "no command message answer\n");
+		goto failed;
+	}
+
+	memcpy(in, priv->cmd_msg_buffer, sizeof(struct usb_8dev_cmd_msg));
+
+	if (in->begin != USB_8DEV_CMD_START || in->end != USB_8DEV_CMD_END ||
+			num_bytes_read != 16 || in->opt1 != 0)
+		err = -EPROTO;
+
+failed:
+	mutex_unlock(&priv->usb_8dev_cmd_lock);
+	return err;
+}
+
+/* Send open command to device */
+static int usb_8dev_cmd_open(struct usb_8dev_priv *priv)
+{
+	struct can_bittiming *bt = &priv->can.bittiming;
+	struct usb_8dev_cmd_msg outmsg;
+	struct usb_8dev_cmd_msg inmsg;
+	u32 ctrlmode = priv->can.ctrlmode;
+	u32 flags = USB_8DEV_STATUS_FRAME;
+	__be32 beflags;
+	__be16 bebrp;
+
+	memset(&outmsg, 0, sizeof(outmsg));
+	outmsg.command = USB_8DEV_OPEN;
+	outmsg.opt1 = USB_8DEV_BAUD_MANUAL;
+	outmsg.data[0] = bt->prop_seg + bt->phase_seg1;
+	outmsg.data[1] = bt->phase_seg2;
+	outmsg.data[2] = bt->sjw;
+
+	/* BRP */
+	bebrp = cpu_to_be16((u16)bt->brp);
+	memcpy(&outmsg.data[3], &bebrp, sizeof(bebrp));
+
+	/* flags */
+	if (ctrlmode & CAN_CTRLMODE_LOOPBACK)
+		flags |= USB_8DEV_LOOPBACK;
+	if (ctrlmode & CAN_CTRLMODE_LISTENONLY)
+		flags |= USB_8DEV_SILENT;
+	if (ctrlmode & CAN_CTRLMODE_ONE_SHOT)
+		flags |= USB_8DEV_DISABLE_AUTO_RESTRANS;
+
+	beflags = cpu_to_be32(flags);
+	memcpy(&outmsg.data[5], &beflags, sizeof(beflags));
+
+	return usb_8dev_send_cmd(priv, &outmsg, &inmsg);
+}
+
+/* Send close command to device */
+static int usb_8dev_cmd_close(struct usb_8dev_priv *priv)
+{
+	struct usb_8dev_cmd_msg inmsg;
+	struct usb_8dev_cmd_msg outmsg = {
+		.channel = 0,
+		.command = USB_8DEV_CLOSE,
+		.opt1 = 0,
+		.opt2 = 0
+	};
+
+	return usb_8dev_send_cmd(priv, &outmsg, &inmsg);
+}
+
+/* Get firmware and hardware version */
+static int usb_8dev_cmd_version(struct usb_8dev_priv *priv, u32 *res)
+{
+	struct usb_8dev_cmd_msg	inmsg;
+	struct usb_8dev_cmd_msg	outmsg = {
+		.channel = 0,
+		.command = USB_8DEV_GET_SOFTW_HARDW_VER,
+		.opt1 = 0,
+		.opt2 = 0
+	};
+
+	int err = usb_8dev_send_cmd(priv, &outmsg, &inmsg);
+	if (err)
+		return err;
+
+	*res = be32_to_cpup((__be32 *)inmsg.data);
+
+	return err;
+}
+
+/* Set network device mode
+ *
+ * Maybe we should leave this function empty, because the device
+ * set mode variable with open command.
+ */
+static int usb_8dev_set_mode(struct net_device *netdev, enum can_mode mode)
+{
+	struct usb_8dev_priv *priv = netdev_priv(netdev);
+	int err = 0;
+
+	switch (mode) {
+	case CAN_MODE_START:
+		err = usb_8dev_cmd_open(priv);
+		if (err)
+			netdev_warn(netdev, "couldn't start device");
+		break;
+
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return err;
+}
+
+/* Read error/status frames */
+static void usb_8dev_rx_err_msg(struct usb_8dev_priv *priv,
+				struct usb_8dev_rx_msg *msg)
+{
+	struct can_frame *cf;
+	struct sk_buff *skb;
+	struct net_device_stats *stats = &priv->netdev->stats;
+
+	/* Error message:
+	 * byte 0: Status
+	 * byte 1: bit   7: Receive Passive
+	 * byte 1: bit 0-6: Receive Error Counter
+	 * byte 2: Transmit Error Counter
+	 * byte 3: Always 0 (maybe reserved for future use)
+	 */
+
+	u8 state = msg->data[0];
+	u8 rxerr = msg->data[1] & USB_8DEV_RP_MASK;
+	u8 txerr = msg->data[2];
+	int rx_errors = 0;
+	int tx_errors = 0;
+
+	skb = alloc_can_err_skb(priv->netdev, &cf);
+	if (!skb)
+		return;
+
+	switch (state) {
+	case USB_8DEV_STATUSMSG_OK:
+		priv->can.state = CAN_STATE_ERROR_ACTIVE;
+		cf->can_id |= CAN_ERR_PROT;
+		cf->data[2] = CAN_ERR_PROT_ACTIVE;
+		break;
+	case USB_8DEV_STATUSMSG_BUSOFF:
+		priv->can.state = CAN_STATE_BUS_OFF;
+		cf->can_id |= CAN_ERR_BUSOFF;
+		can_bus_off(priv->netdev);
+		break;
+	case USB_8DEV_STATUSMSG_OVERRUN:
+	case USB_8DEV_STATUSMSG_BUSLIGHT:
+	case USB_8DEV_STATUSMSG_BUSHEAVY:
+		cf->can_id |= CAN_ERR_CRTL;
+		break;
+	default:
+		priv->can.state = CAN_STATE_ERROR_WARNING;
+		cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+		priv->can.can_stats.bus_error++;
+		break;
+	}
+
+	switch (state) {
+	case USB_8DEV_STATUSMSG_OK:
+	case USB_8DEV_STATUSMSG_BUSOFF:
+		break;
+	case USB_8DEV_STATUSMSG_ACK:
+		cf->can_id |= CAN_ERR_ACK;
+		tx_errors = 1;
+		break;
+	case USB_8DEV_STATUSMSG_CRC:
+		cf->data[2] |= CAN_ERR_PROT_UNSPEC;
+		cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ |
+			       CAN_ERR_PROT_LOC_CRC_DEL;
+		rx_errors = 1;
+		break;
+	case USB_8DEV_STATUSMSG_BIT0:
+		cf->data[2] |= CAN_ERR_PROT_BIT0;
+		tx_errors = 1;
+		break;
+	case USB_8DEV_STATUSMSG_BIT1:
+		cf->data[2] |= CAN_ERR_PROT_BIT1;
+		tx_errors = 1;
+		break;
+	case USB_8DEV_STATUSMSG_FORM:
+		cf->data[2] |= CAN_ERR_PROT_FORM;
+		rx_errors = 1;
+		break;
+	case USB_8DEV_STATUSMSG_STUFF:
+		cf->data[2] |= CAN_ERR_PROT_STUFF;
+		rx_errors = 1;
+		break;
+	case USB_8DEV_STATUSMSG_OVERRUN:
+		cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
+		stats->rx_over_errors++;
+		rx_errors = 1;
+		break;
+	case USB_8DEV_STATUSMSG_BUSLIGHT:
+		priv->can.state = CAN_STATE_ERROR_WARNING;
+		cf->data[1] = (txerr > rxerr) ?
+			CAN_ERR_CRTL_TX_WARNING :
+			CAN_ERR_CRTL_RX_WARNING;
+		priv->can.can_stats.error_warning++;
+		break;
+	case USB_8DEV_STATUSMSG_BUSHEAVY:
+		priv->can.state = CAN_STATE_ERROR_PASSIVE;
+		cf->data[1] = (txerr > rxerr) ?
+			CAN_ERR_CRTL_TX_PASSIVE :
+			CAN_ERR_CRTL_RX_PASSIVE;
+		priv->can.can_stats.error_passive++;
+		break;
+	default:
+		netdev_warn(priv->netdev,
+			    "Unknown status/error message (%d)\n", state);
+		break;
+	}
+
+	if (tx_errors) {
+		cf->data[2] |= CAN_ERR_PROT_TX;
+		stats->tx_errors++;
+	}
+
+	if (rx_errors)
+		stats->rx_errors++;
+
+	cf->data[6] = txerr;
+	cf->data[7] = rxerr;
+
+	priv->bec.txerr = txerr;
+	priv->bec.rxerr = rxerr;
+
+	netif_rx(skb);
+
+	stats->rx_packets++;
+	stats->rx_bytes += cf->can_dlc;
+}
+
+/* Read data and status frames */
+static void usb_8dev_rx_can_msg(struct usb_8dev_priv *priv,
+				struct usb_8dev_rx_msg *msg)
+{
+	struct can_frame *cf;
+	struct sk_buff *skb;
+	struct net_device_stats *stats = &priv->netdev->stats;
+
+	if (msg->type == USB_8DEV_TYPE_ERROR_FRAME &&
+		   msg->flags == USB_8DEV_ERR_FLAG) {
+		usb_8dev_rx_err_msg(priv, msg);
+	} else if (msg->type == USB_8DEV_TYPE_CAN_FRAME) {
+		skb = alloc_can_skb(priv->netdev, &cf);
+		if (!skb)
+			return;
+
+		cf->can_id = be32_to_cpu(msg->id);
+		cf->can_dlc = get_can_dlc(msg->dlc & 0xF);
+
+		if (msg->flags & USB_8DEV_EXTID)
+			cf->can_id |= CAN_EFF_FLAG;
+
+		if (msg->flags & USB_8DEV_RTR)
+			cf->can_id |= CAN_RTR_FLAG;
+		else
+			memcpy(cf->data, msg->data, cf->can_dlc);
+
+		netif_rx(skb);
+
+		stats->rx_packets++;
+		stats->rx_bytes += cf->can_dlc;
+
+		can_led_event(priv->netdev, CAN_LED_EVENT_RX);
+	} else {
+		netdev_warn(priv->netdev, "frame type %d unknown",
+			 msg->type);
+	}
+
+}
+
+/* Callback for reading data from device
+ *
+ * Check urb status, call read function and resubmit urb read operation.
+ */
+static void usb_8dev_read_bulk_callback(struct urb *urb)
+{
+	struct usb_8dev_priv *priv = urb->context;
+	struct net_device *netdev;
+	int retval;
+	int pos = 0;
+
+	netdev = priv->netdev;
+
+	if (!netif_device_present(netdev))
+		return;
+
+	switch (urb->status) {
+	case 0: /* success */
+		break;
+
+	case -ENOENT:
+	case -ESHUTDOWN:
+		return;
+
+	default:
+		netdev_info(netdev, "Rx URB aborted (%d)\n",
+			 urb->status);
+		goto resubmit_urb;
+	}
+
+	while (pos < urb->actual_length) {
+		struct usb_8dev_rx_msg *msg;
+
+		if (pos + sizeof(struct usb_8dev_rx_msg) > urb->actual_length) {
+			netdev_err(priv->netdev, "format error\n");
+			break;
+		}
+
+		msg = (struct usb_8dev_rx_msg *)(urb->transfer_buffer + pos);
+		usb_8dev_rx_can_msg(priv, msg);
+
+		pos += sizeof(struct usb_8dev_rx_msg);
+	}
+
+resubmit_urb:
+	usb_fill_bulk_urb(urb, priv->udev,
+			  usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_RX),
+			  urb->transfer_buffer, RX_BUFFER_SIZE,
+			  usb_8dev_read_bulk_callback, priv);
+
+	retval = usb_submit_urb(urb, GFP_ATOMIC);
+
+	if (retval == -ENODEV)
+		netif_device_detach(netdev);
+	else if (retval)
+		netdev_err(netdev,
+			"failed resubmitting read bulk urb: %d\n", retval);
+}
+
+/* Callback handler for write operations
+ *
+ * Free allocated buffers, check transmit status and
+ * calculate statistic.
+ */
+static void usb_8dev_write_bulk_callback(struct urb *urb)
+{
+	struct usb_8dev_tx_urb_context *context = urb->context;
+	struct usb_8dev_priv *priv;
+	struct net_device *netdev;
+
+	BUG_ON(!context);
+
+	priv = context->priv;
+	netdev = priv->netdev;
+
+	/* free up our allocated buffer */
+	usb_free_coherent(urb->dev, urb->transfer_buffer_length,
+			  urb->transfer_buffer, urb->transfer_dma);
+
+	atomic_dec(&priv->active_tx_urbs);
+
+	if (!netif_device_present(netdev))
+		return;
+
+	if (urb->status)
+		netdev_info(netdev, "Tx URB aborted (%d)\n",
+			 urb->status);
+
+	netdev->stats.tx_packets++;
+	netdev->stats.tx_bytes += context->dlc;
+
+	can_get_echo_skb(netdev, context->echo_index);
+
+	can_led_event(netdev, CAN_LED_EVENT_TX);
+
+	/* Release context */
+	context->echo_index = MAX_TX_URBS;
+
+	netif_wake_queue(netdev);
+}
+
+/* Send data to device */
+static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb,
+				      struct net_device *netdev)
+{
+	struct usb_8dev_priv *priv = netdev_priv(netdev);
+	struct net_device_stats *stats = &netdev->stats;
+	struct can_frame *cf = (struct can_frame *) skb->data;
+	struct usb_8dev_tx_msg *msg;
+	struct urb *urb;
+	struct usb_8dev_tx_urb_context *context = NULL;
+	u8 *buf;
+	int i, err;
+	size_t size = sizeof(struct usb_8dev_tx_msg);
+
+	if (can_dropped_invalid_skb(netdev, skb))
+		return NETDEV_TX_OK;
+
+	/* create a URB, and a buffer for it, and copy the data to the URB */
+	urb = usb_alloc_urb(0, GFP_ATOMIC);
+	if (!urb) {
+		netdev_err(netdev, "No memory left for URBs\n");
+		goto nomem;
+	}
+
+	buf = usb_alloc_coherent(priv->udev, size, GFP_ATOMIC,
+				 &urb->transfer_dma);
+	if (!buf) {
+		netdev_err(netdev, "No memory left for USB buffer\n");
+		goto nomembuf;
+	}
+
+	memset(buf, 0, size);
+
+	msg = (struct usb_8dev_tx_msg *)buf;
+	msg->begin = USB_8DEV_DATA_START;
+	msg->flags = 0x00;
+
+	if (cf->can_id & CAN_RTR_FLAG)
+		msg->flags |= USB_8DEV_RTR;
+
+	if (cf->can_id & CAN_EFF_FLAG)
+		msg->flags |= USB_8DEV_EXTID;
+
+	msg->id = cpu_to_be32(cf->can_id & CAN_ERR_MASK);
+	msg->dlc = cf->can_dlc;
+	memcpy(msg->data, cf->data, cf->can_dlc);
+	msg->end = USB_8DEV_DATA_END;
+
+	for (i = 0; i < MAX_TX_URBS; i++) {
+		if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
+			context = &priv->tx_contexts[i];
+			break;
+		}
+	}
+
+	/* May never happen! When this happens we'd more URBs in flight as
+	 * allowed (MAX_TX_URBS).
+	 */
+	if (!context)
+		goto nofreecontext;
+
+	context->priv = priv;
+	context->echo_index = i;
+	context->dlc = cf->can_dlc;
+
+	usb_fill_bulk_urb(urb, priv->udev,
+			  usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_TX),
+			  buf, size, usb_8dev_write_bulk_callback, context);
+	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+	usb_anchor_urb(urb, &priv->tx_submitted);
+
+	can_put_echo_skb(skb, netdev, context->echo_index);
+
+	atomic_inc(&priv->active_tx_urbs);
+
+	err = usb_submit_urb(urb, GFP_ATOMIC);
+	if (unlikely(err))
+		goto failed;
+	else if (atomic_read(&priv->active_tx_urbs) >= MAX_TX_URBS)
+		/* Slow down tx path */
+		netif_stop_queue(netdev);
+
+	/* Release our reference to this URB, the USB core will eventually free
+	 * it entirely.
+	 */
+	usb_free_urb(urb);
+
+	return NETDEV_TX_OK;
+
+nofreecontext:
+	usb_unanchor_urb(urb);
+	usb_free_coherent(priv->udev, size, buf, urb->transfer_dma);
+
+	netdev_warn(netdev, "couldn't find free context");
+
+	return NETDEV_TX_BUSY;
+
+failed:
+	can_free_echo_skb(netdev, context->echo_index);
+
+	usb_unanchor_urb(urb);
+	usb_free_coherent(priv->udev, size, buf, urb->transfer_dma);
+
+	atomic_dec(&priv->active_tx_urbs);
+
+	if (err == -ENODEV)
+		netif_device_detach(netdev);
+	else
+		netdev_warn(netdev, "failed tx_urb %d\n", err);
+
+nomembuf:
+	usb_free_urb(urb);
+
+nomem:
+	dev_kfree_skb(skb);
+	stats->tx_dropped++;
+
+	return NETDEV_TX_OK;
+}
+
+static int usb_8dev_get_berr_counter(const struct net_device *netdev,
+				     struct can_berr_counter *bec)
+{
+	struct usb_8dev_priv *priv = netdev_priv(netdev);
+
+	bec->txerr = priv->bec.txerr;
+	bec->rxerr = priv->bec.rxerr;
+
+	return 0;
+}
+
+/* Start USB device */
+static int usb_8dev_start(struct usb_8dev_priv *priv)
+{
+	struct net_device *netdev = priv->netdev;
+	int err, i;
+
+	for (i = 0; i < MAX_RX_URBS; i++) {
+		struct urb *urb = NULL;
+		u8 *buf;
+
+		/* create a URB, and a buffer for it */
+		urb = usb_alloc_urb(0, GFP_KERNEL);
+		if (!urb) {
+			netdev_err(netdev, "No memory left for URBs\n");
+			err = -ENOMEM;
+			break;
+		}
+
+		buf = usb_alloc_coherent(priv->udev, RX_BUFFER_SIZE, GFP_KERNEL,
+					 &urb->transfer_dma);
+		if (!buf) {
+			netdev_err(netdev, "No memory left for USB buffer\n");
+			usb_free_urb(urb);
+			err = -ENOMEM;
+			break;
+		}
+
+		usb_fill_bulk_urb(urb, priv->udev,
+				  usb_rcvbulkpipe(priv->udev,
+						  USB_8DEV_ENDP_DATA_RX),
+				  buf, RX_BUFFER_SIZE,
+				  usb_8dev_read_bulk_callback, priv);
+		urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+		usb_anchor_urb(urb, &priv->rx_submitted);
+
+		err = usb_submit_urb(urb, GFP_KERNEL);
+		if (err) {
+			usb_unanchor_urb(urb);
+			usb_free_coherent(priv->udev, RX_BUFFER_SIZE, buf,
+					  urb->transfer_dma);
+			break;
+		}
+
+		/* Drop reference, USB core will take care of freeing it */
+		usb_free_urb(urb);
+	}
+
+	/* Did we submit any URBs */
+	if (i == 0) {
+		netdev_warn(netdev, "couldn't setup read URBs\n");
+		return err;
+	}
+
+	/* Warn if we've couldn't transmit all the URBs */
+	if (i < MAX_RX_URBS)
+		netdev_warn(netdev, "rx performance may be slow\n");
+
+	err = usb_8dev_cmd_open(priv);
+	if (err)
+		goto failed;
+
+	priv->can.state = CAN_STATE_ERROR_ACTIVE;
+
+	return 0;
+
+failed:
+	if (err == -ENODEV)
+		netif_device_detach(priv->netdev);
+
+	netdev_warn(netdev, "couldn't submit control: %d\n", err);
+
+	return err;
+}
+
+/* Open USB device */
+static int usb_8dev_open(struct net_device *netdev)
+{
+	struct usb_8dev_priv *priv = netdev_priv(netdev);
+	int err;
+
+	/* common open */
+	err = open_candev(netdev);
+	if (err)
+		return err;
+
+	can_led_event(netdev, CAN_LED_EVENT_OPEN);
+
+	/* finally start device */
+	err = usb_8dev_start(priv);
+	if (err) {
+		if (err == -ENODEV)
+			netif_device_detach(priv->netdev);
+
+		netdev_warn(netdev, "couldn't start device: %d\n",
+			 err);
+
+		close_candev(netdev);
+
+		return err;
+	}
+
+	netif_start_queue(netdev);
+
+	return 0;
+}
+
+static void unlink_all_urbs(struct usb_8dev_priv *priv)
+{
+	int i;
+
+	usb_kill_anchored_urbs(&priv->rx_submitted);
+
+	usb_kill_anchored_urbs(&priv->tx_submitted);
+	atomic_set(&priv->active_tx_urbs, 0);
+
+	for (i = 0; i < MAX_TX_URBS; i++)
+		priv->tx_contexts[i].echo_index = MAX_TX_URBS;
+}
+
+/* Close USB device */
+static int usb_8dev_close(struct net_device *netdev)
+{
+	struct usb_8dev_priv *priv = netdev_priv(netdev);
+	int err = 0;
+
+	/* Send CLOSE command to CAN controller */
+	err = usb_8dev_cmd_close(priv);
+	if (err)
+		netdev_warn(netdev, "couldn't stop device");
+
+	priv->can.state = CAN_STATE_STOPPED;
+
+	netif_stop_queue(netdev);
+
+	/* Stop polling */
+	unlink_all_urbs(priv);
+
+	close_candev(netdev);
+
+	can_led_event(netdev, CAN_LED_EVENT_STOP);
+
+	return err;
+}
+
+static const struct net_device_ops usb_8dev_netdev_ops = {
+	.ndo_open = usb_8dev_open,
+	.ndo_stop = usb_8dev_close,
+	.ndo_start_xmit = usb_8dev_start_xmit,
+};
+
+static const struct can_bittiming_const usb_8dev_bittiming_const = {
+	.name = "usb_8dev",
+	.tseg1_min = 1,
+	.tseg1_max = 16,
+	.tseg2_min = 1,
+	.tseg2_max = 8,
+	.sjw_max = 4,
+	.brp_min = 1,
+	.brp_max = 1024,
+	.brp_inc = 1,
+};
+
+/* Probe USB device
+ *
+ * Check device and firmware.
+ * Set supported modes and bittiming constants.
+ * Allocate some memory.
+ */
+static int usb_8dev_probe(struct usb_interface *intf,
+			 const struct usb_device_id *id)
+{
+	struct net_device *netdev;
+	struct usb_8dev_priv *priv;
+	int i, err = -ENOMEM;
+	u32 version;
+	char buf[18];
+	struct usb_device *usbdev = interface_to_usbdev(intf);
+
+	/* product id looks strange, better we also check iProduct string */
+	if (usb_string(usbdev, usbdev->descriptor.iProduct, buf,
+		       sizeof(buf)) > 0 && strcmp(buf, "USB2CAN converter")) {
+		dev_info(&usbdev->dev, "ignoring: not an USB2CAN converter\n");
+		return -ENODEV;
+	}
+
+	netdev = alloc_candev(sizeof(struct usb_8dev_priv), MAX_TX_URBS);
+	if (!netdev) {
+		dev_err(&intf->dev, "Couldn't alloc candev\n");
+		return -ENOMEM;
+	}
+
+	priv = netdev_priv(netdev);
+
+	priv->udev = usbdev;
+	priv->netdev = netdev;
+
+	priv->can.state = CAN_STATE_STOPPED;
+	priv->can.clock.freq = USB_8DEV_ABP_CLOCK;
+	priv->can.bittiming_const = &usb_8dev_bittiming_const;
+	priv->can.do_set_mode = usb_8dev_set_mode;
+	priv->can.do_get_berr_counter = usb_8dev_get_berr_counter;
+	priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
+				      CAN_CTRLMODE_LISTENONLY |
+				      CAN_CTRLMODE_ONE_SHOT;
+
+	netdev->netdev_ops = &usb_8dev_netdev_ops;
+
+	netdev->flags |= IFF_ECHO; /* we support local echo */
+
+	init_usb_anchor(&priv->rx_submitted);
+
+	init_usb_anchor(&priv->tx_submitted);
+	atomic_set(&priv->active_tx_urbs, 0);
+
+	for (i = 0; i < MAX_TX_URBS; i++)
+		priv->tx_contexts[i].echo_index = MAX_TX_URBS;
+
+	priv->cmd_msg_buffer = kzalloc(sizeof(struct usb_8dev_cmd_msg),
+				      GFP_KERNEL);
+	if (!priv->cmd_msg_buffer) {
+		netdev_err(netdev, "Couldn't alloc Tx buffer\n");
+		goto cleanup_candev;
+	}
+
+	usb_set_intfdata(intf, priv);
+
+	SET_NETDEV_DEV(netdev, &intf->dev);
+
+	mutex_init(&priv->usb_8dev_cmd_lock);
+
+	err = register_candev(netdev);
+	if (err) {
+		netdev_err(netdev,
+			"couldn't register CAN device: %d\n", err);
+		goto cleanup_cmd_msg_buffer;
+	}
+
+	err = usb_8dev_cmd_version(priv, &version);
+	if (err) {
+		netdev_err(netdev, "can't get firmware version\n");
+		goto cleanup_cmd_msg_buffer;
+	} else {
+		netdev_info(netdev,
+			 "firmware: %d.%d, hardware: %d.%d\n",
+			 (version>>24) & 0xff, (version>>16) & 0xff,
+			 (version>>8) & 0xff, version & 0xff);
+	}
+
+	devm_can_led_init(netdev);
+
+	return 0;
+
+cleanup_cmd_msg_buffer:
+	kfree(priv->cmd_msg_buffer);
+
+cleanup_candev:
+	free_candev(netdev);
+
+	return err;
+
+}
+
+/* Called by the usb core when driver is unloaded or device is removed */
+static void usb_8dev_disconnect(struct usb_interface *intf)
+{
+	struct usb_8dev_priv *priv = usb_get_intfdata(intf);
+
+	usb_set_intfdata(intf, NULL);
+
+	if (priv) {
+		netdev_info(priv->netdev, "device disconnected\n");
+
+		unregister_netdev(priv->netdev);
+		free_candev(priv->netdev);
+
+		unlink_all_urbs(priv);
+	}
+
+}
+
+static struct usb_driver usb_8dev_driver = {
+	.name =		"usb_8dev",
+	.probe =	usb_8dev_probe,
+	.disconnect =	usb_8dev_disconnect,
+	.id_table =	usb_8dev_table,
+};
+
+module_usb_driver(usb_8dev_driver);
+
+MODULE_AUTHOR("Bernd Krumboeck <krumboeck@universalnet.at>");
+MODULE_DESCRIPTION("CAN driver for 8 devices USB2CAN interfaces");
+MODULE_LICENSE("GPL v2");

include/linux/can/dev.h

@@ -16,6 +16,7 @@
 #include <linux/can.h>
 #include <linux/can/netlink.h>
 #include <linux/can/error.h>
+#include <linux/can/led.h>
 
 /*
  * CAN mode
@@ -52,6 +53,13 @@ struct can_priv {
 
 	unsigned int echo_skb_max;
 	struct sk_buff **echo_skb;
+
+#ifdef CONFIG_CAN_LEDS
+	struct led_trigger *tx_led_trig;
+	char tx_led_trig_name[CAN_LED_NAME_SZ];
+	struct led_trigger *rx_led_trig;
+	char rx_led_trig_name[CAN_LED_NAME_SZ];
+#endif
 };
 
 /*
@@ -98,6 +106,9 @@ u8 can_len2dlc(u8 len);
 struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max);
 void free_candev(struct net_device *dev);
 
+/* a candev safe wrapper around netdev_priv */
+struct can_priv *safe_candev_priv(struct net_device *dev);
+
 int open_candev(struct net_device *dev);
 void close_candev(struct net_device *dev);
 

include/linux/can/led.h

+/*
+ * Copyright 2012, Fabio Baltieri <fabio.baltieri@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef CAN_LED_H
+#define CAN_LED_H
+
+#include <linux/if.h>
+#include <linux/leds.h>
+
+enum can_led_event {
+	CAN_LED_EVENT_OPEN,
+	CAN_LED_EVENT_STOP,
+	CAN_LED_EVENT_TX,
+	CAN_LED_EVENT_RX,
+};
+
+#ifdef CONFIG_CAN_LEDS
+
+/* keep space for interface name + "-tx"/"-rx" suffix and null terminator */
+#define CAN_LED_NAME_SZ (IFNAMSIZ + 4)
+
+void can_led_event(struct net_device *netdev, enum can_led_event event);
+void devm_can_led_init(struct net_device *netdev);
+int __init can_led_notifier_init(void);
+void __exit can_led_notifier_exit(void);
+
+#else
+
+static inline void can_led_event(struct net_device *netdev,
+				 enum can_led_event event)
+{
+}
+static inline void devm_can_led_init(struct net_device *netdev)
+{
+}
+static inline int can_led_notifier_init(void)
+{
+	return 0;
+}
+static inline void can_led_notifier_exit(void)
+{
+}
+
+#endif
+
+#endif

include/linux/can/skb.h

+/*
+ * linux/can/skb.h
+ *
+ * Definitions for the CAN network socket buffer
+ *
+ * Copyright (C) 2012 Oliver Hartkopp <socketcan@hartkopp.net>
+ *
+ */
+
+#ifndef CAN_SKB_H
+#define CAN_SKB_H
+
+#include <linux/types.h>
+#include <linux/can.h>
+
+/*
+ * The struct can_skb_priv is used to transport additional information along
+ * with the stored struct can(fd)_frame that can not be contained in existing
+ * struct sk_buff elements.
+ * N.B. that this information must not be modified in cloned CAN sk_buffs.
+ * To modify the CAN frame content or the struct can_skb_priv content
+ * skb_copy() needs to be used instead of skb_clone().
+ */
+
+/**
+ * struct can_skb_priv - private additional data inside CAN sk_buffs
+ * @ifindex:	ifindex of the first interface the CAN frame appeared on
+ * @cf:		align to the following CAN frame at skb->data
+ */
+struct can_skb_priv {
+	int ifindex;
+	struct can_frame cf[0];
+};
+
+#endif /* CAN_SKB_H */

include/uapi/linux/can/gw.h

@@ -44,6 +44,7 @@ enum {
 	CGW_SRC_IF,	/* ifindex of source network interface */
 	CGW_DST_IF,	/* ifindex of destination network interface */
 	CGW_FILTER,	/* specify struct can_filter on source CAN device */
+	CGW_DELETED,	/* number of deleted CAN frames (see max_hops param) */
 	__CGW_MAX
 };
 
@@ -51,6 +52,7 @@ enum {
 
 #define CGW_FLAGS_CAN_ECHO 0x01
 #define CGW_FLAGS_CAN_SRC_TSTAMP 0x02
+#define CGW_FLAGS_CAN_IIF_TX_OK 0x04
 
 #define CGW_MOD_FUNCS 4 /* AND OR XOR SET */
 

net/can/Kconfig

@@ -16,10 +16,11 @@ menuconfig CAN
 	  If you want CAN support you should say Y here and also to the
 	  specific driver for your controller(s) below.
 
+if CAN
+
 config CAN_RAW
 	tristate "Raw CAN Protocol (raw access with CAN-ID filtering)"
-	depends on CAN
-	default N
+	default y
 	---help---
 	  The raw CAN protocol option offers access to the CAN bus via
 	  the BSD socket API. You probably want to use the raw socket in
@@ -29,8 +30,7 @@ config CAN_RAW
 
 config CAN_BCM
 	tristate "Broadcast Manager CAN Protocol (with content filtering)"
-	depends on CAN
-	default N
+	default y
 	---help---
 	  The Broadcast Manager offers content filtering, timeout monitoring,
 	  sending of RTR frames, and cyclic CAN messages without permanent user
@@ -42,8 +42,7 @@ config CAN_BCM
 
 config CAN_GW
 	tristate "CAN Gateway/Router (with netlink configuration)"
-	depends on CAN
-	default N
+	default y
 	---help---
 	  The CAN Gateway/Router is used to route (and modify) CAN frames.
 	  It is based on the PF_CAN core infrastructure for msg filtering and
@@ -53,3 +52,5 @@ config CAN_GW
 	  by the netlink configuration interface known e.g. from iptables.
 
 source "drivers/net/can/Kconfig"
+
+endif

net/can/bcm.c

@@ -54,6 +54,7 @@
 #include <linux/skbuff.h>
 #include <linux/can.h>
 #include <linux/can/core.h>
+#include <linux/can/skb.h>
 #include <linux/can/bcm.h>
 #include <linux/slab.h>
 #include <net/sock.h>
@@ -256,10 +257,13 @@ static void bcm_can_tx(struct bcm_op *op)
 		return;
 	}
 
-	skb = alloc_skb(CFSIZ, gfp_any());
+	skb = alloc_skb(CFSIZ + sizeof(struct can_skb_priv), gfp_any());
 	if (!skb)
 		goto out;
 
+	skb_reserve(skb, sizeof(struct can_skb_priv));
+	((struct can_skb_priv *)(skb->head))->ifindex = dev->ifindex;
+
 	memcpy(skb_put(skb, CFSIZ), cf, CFSIZ);
 
 	/* send with loopback */
@@ -1199,11 +1203,12 @@ static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk)
 	if (!ifindex)
 		return -ENODEV;
 
-	skb = alloc_skb(CFSIZ, GFP_KERNEL);
-
+	skb = alloc_skb(CFSIZ + sizeof(struct can_skb_priv), GFP_KERNEL);
 	if (!skb)
 		return -ENOMEM;
 
+	skb_reserve(skb, sizeof(struct can_skb_priv));
+
 	err = memcpy_fromiovec(skb_put(skb, CFSIZ), msg->msg_iov, CFSIZ);
 	if (err < 0) {
 		kfree_skb(skb);
@@ -1216,6 +1221,7 @@ static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk)
 		return -ENODEV;
 	}
 
+	((struct can_skb_priv *)(skb->head))->ifindex = dev->ifindex;
 	skb->dev = dev;
 	skb->sk  = sk;
 	err = can_send(skb, 1); /* send with loopback */

net/can/gw.c

@@ -42,6 +42,7 @@
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/types.h>
+#include <linux/kernel.h>
 #include <linux/list.h>
 #include <linux/spinlock.h>
 #include <linux/rcupdate.h>
@@ -52,19 +53,31 @@
 #include <linux/skbuff.h>
 #include <linux/can.h>
 #include <linux/can/core.h>
+#include <linux/can/skb.h>
 #include <linux/can/gw.h>
 #include <net/rtnetlink.h>
 #include <net/net_namespace.h>
 #include <net/sock.h>
 
-#define CAN_GW_VERSION "20101209"
-static __initconst const char banner[] =
-	KERN_INFO "can: netlink gateway (rev " CAN_GW_VERSION ")\n";
+#define CAN_GW_VERSION "20130117"
+#define CAN_GW_NAME "can-gw"
 
 MODULE_DESCRIPTION("PF_CAN netlink gateway");
 MODULE_LICENSE("Dual BSD/GPL");
 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
-MODULE_ALIAS("can-gw");
+MODULE_ALIAS(CAN_GW_NAME);
+
+#define CGW_MIN_HOPS 1
+#define CGW_MAX_HOPS 6
+#define CGW_DEFAULT_HOPS 1
+
+static unsigned int max_hops __read_mostly = CGW_DEFAULT_HOPS;
+module_param(max_hops, uint, S_IRUGO);
+MODULE_PARM_DESC(max_hops,
+		 "maximum " CAN_GW_NAME " routing hops for CAN frames "
+		 "(valid values: " __stringify(CGW_MIN_HOPS) "-"
+		 __stringify(CGW_MAX_HOPS) " hops, "
+		 "default: " __stringify(CGW_DEFAULT_HOPS) ")");
 
 static HLIST_HEAD(cgw_list);
 static struct notifier_block notifier;
@@ -118,6 +131,7 @@ struct cgw_job {
 	struct rcu_head rcu;
 	u32 handled_frames;
 	u32 dropped_frames;
+	u32 deleted_frames;
 	struct cf_mod mod;
 	union {
 		/* CAN frame data source */
@@ -338,15 +352,40 @@ static void can_can_gw_rcv(struct sk_buff *skb, void *data)
 	struct sk_buff *nskb;
 	int modidx = 0;
 
-	/* do not handle already routed frames - see comment below */
-	if (skb_mac_header_was_set(skb))
+	/*
+	 * Do not handle CAN frames routed more than 'max_hops' times.
+	 * In general we should never catch this delimiter which is intended
+	 * to cover a misconfiguration protection (e.g. circular CAN routes).
+	 *
+	 * The Controller Area Network controllers only accept CAN frames with
+	 * correct CRCs - which are not visible in the controller registers.
+	 * According to skbuff.h documentation the csum_start element for IP
+	 * checksums is undefined/unsued when ip_summed == CHECKSUM_UNNECESSARY.
+	 * Only CAN skbs can be processed here which already have this property.
+	 */
+
+#define cgw_hops(skb) ((skb)->csum_start)
+
+	BUG_ON(skb->ip_summed != CHECKSUM_UNNECESSARY);
+
+	if (cgw_hops(skb) >= max_hops) {
+		/* indicate deleted frames due to misconfiguration */
+		gwj->deleted_frames++;
 		return;
+	}
 
 	if (!(gwj->dst.dev->flags & IFF_UP)) {
 		gwj->dropped_frames++;
 		return;
 	}
 
+	/* is sending the skb back to the incoming interface not allowed? */
+	if (!(gwj->flags & CGW_FLAGS_CAN_IIF_TX_OK) &&
+	    skb_headroom(skb) == sizeof(struct can_skb_priv) &&
+	    (((struct can_skb_priv *)(skb->head))->ifindex ==
+	     gwj->dst.dev->ifindex))
+		return;
+
 	/*
 	 * clone the given skb, which has not been done in can_rcv()
 	 *
@@ -363,15 +402,8 @@ static void can_can_gw_rcv(struct sk_buff *skb, void *data)
 		return;
 	}
 
-	/*
-	 * Mark routed frames by setting some mac header length which is
-	 * not relevant for the CAN frames located in the skb->data section.
-	 *
-	 * As dev->header_ops is not set in CAN netdevices no one is ever
-	 * accessing the various header offsets in the CAN skbuffs anyway.
-	 * E.g. using the packet socket to read CAN frames is still working.
-	 */
-	skb_set_mac_header(nskb, 8);
+	/* put the incremented hop counter in the cloned skb */
+	cgw_hops(nskb) = cgw_hops(skb) + 1;
 	nskb->dev = gwj->dst.dev;
 
 	/* pointer to modifiable CAN frame */
@@ -472,6 +504,11 @@ static int cgw_put_job(struct sk_buff *skb, struct cgw_job *gwj, int type,
 			goto cancel;
 	}
 
+	if (gwj->deleted_frames) {
+		if (nla_put_u32(skb, CGW_DELETED, gwj->deleted_frames) < 0)
+			goto cancel;
+	}
+
 	/* check non default settings of attributes */
 
 	if (gwj->mod.modtype.and) {
@@ -771,6 +808,7 @@ static int cgw_create_job(struct sk_buff *skb,  struct nlmsghdr *nlh,
 
 	gwj->handled_frames = 0;
 	gwj->dropped_frames = 0;
+	gwj->deleted_frames = 0;
 	gwj->flags = r->flags;
 	gwj->gwtype = r->gwtype;
 
@@ -895,7 +933,11 @@ static int cgw_remove_job(struct sk_buff *skb,  struct nlmsghdr *nlh, void *arg)
 
 static __init int cgw_module_init(void)
 {
-	printk(banner);
+	/* sanitize given module parameter */
+	max_hops = clamp_t(unsigned int, max_hops, CGW_MIN_HOPS, CGW_MAX_HOPS);
+
+	pr_info("can: netlink gateway (rev " CAN_GW_VERSION ") max_hops=%d\n",
+		max_hops);
 
 	cgw_cache = kmem_cache_create("can_gw", sizeof(struct cgw_job),
 				      0, 0, NULL);

net/can/raw.c

@@ -50,6 +50,7 @@
 #include <linux/skbuff.h>
 #include <linux/can.h>
 #include <linux/can/core.h>
+#include <linux/can/skb.h>
 #include <linux/can/raw.h>
 #include <net/sock.h>
 #include <net/net_namespace.h>
@@ -699,11 +700,14 @@ static int raw_sendmsg(struct kiocb *iocb, struct socket *sock,
 	if (!dev)
 		return -ENXIO;
 
-	skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT,
-				  &err);
+	skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
+				  msg->msg_flags & MSG_DONTWAIT, &err);
 	if (!skb)
 		goto put_dev;
 
+	skb_reserve(skb, sizeof(struct can_skb_priv));
+	((struct can_skb_priv *)(skb->head))->ifindex = dev->ifindex;
+
 	err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
 	if (err < 0)
 		goto free_skb;