Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

10 files changed, 2450 insertions, 50 deletions

diff --git a/drivers/net/can/Kconfig b/drivers/net/can/Kconfig
index 090074372462..772f6d2489ce 100644
--- a/drivers/net/can/Kconfig
+++ b/drivers/net/can/Kconfig
@@ -35,52 +35,15 @@ config CAN_CALC_BITTIMING
 	  arguments "tq", "prop_seg", "phase_seg1", "phase_seg2" and "sjw".
 	  If unsure, say Y.
 
-config CAN_SJA1000
-	depends on CAN_DEV && HAS_IOMEM
-	tristate "Philips SJA1000"
+config CAN_AT91
+	tristate "Atmel AT91 onchip CAN controller"
+	depends on CAN_DEV && ARCH_AT91SAM9263
 	---help---
-	  Driver for the SJA1000 CAN controllers from Philips or NXP
+	  This is a driver for the SoC CAN controller in Atmel's AT91SAM9263.
 
-config CAN_SJA1000_ISA
-	depends on CAN_SJA1000 && ISA
-	tristate "ISA Bus based legacy SJA1000 driver"
-	---help---
-	  This driver adds legacy support for SJA1000 chips connected to
-	  the ISA bus using I/O port, memory mapped or indirect access.
-
-config CAN_SJA1000_PLATFORM
-	depends on CAN_SJA1000
-	tristate "Generic Platform Bus based SJA1000 driver"
-	---help---
-	  This driver adds support for the SJA1000 chips connected to
-	  the "platform bus" (Linux abstraction for directly to the
-	  processor attached devices).  Which can be found on various
-	  boards from Phytec (http://www.phytec.de) like the PCM027,
-	  PCM038.
-
-config CAN_SJA1000_OF_PLATFORM
-	depends on CAN_SJA1000 && PPC_OF
-	tristate "Generic OF Platform Bus based SJA1000 driver"
-	---help---
-	  This driver adds support for the SJA1000 chips connected to
-	  the OpenFirmware "platform bus" found on embedded systems with
-	  OpenFirmware bindings, e.g. if you have a PowerPC based system
-	  you may want to enable this option.
-
-config CAN_EMS_PCI
-	tristate "EMS CPC-PCI, CPC-PCIe and CPC-104P Card"
-	depends on PCI && CAN_SJA1000
-	---help---
-	  This driver is for the one, two or four channel CPC-PCI,
-	  CPC-PCIe and CPC-104P cards from EMS Dr. Thomas Wuensche
-	  (http://www.ems-wuensche.de).
+source "drivers/net/can/sja1000/Kconfig"
 
-config CAN_KVASER_PCI
-	tristate "Kvaser PCIcanx and Kvaser PCIcan PCI Cards"
-	depends on PCI && CAN_SJA1000
-	---help---
-	  This driver is for the the PCIcanx and PCIcan cards (1, 2 or
-	  4 channel) from Kvaser (http://www.kvaser.com).
+source "drivers/net/can/usb/Kconfig"
 
 config CAN_DEBUG_DEVICES
 	bool "CAN devices debugging messages"
diff --git a/drivers/net/can/Makefile b/drivers/net/can/Makefile
index 523a941b358b..0dea62721f2f 100644
--- a/drivers/net/can/Makefile
+++ b/drivers/net/can/Makefile
@@ -7,6 +7,9 @@ obj-$(CONFIG_CAN_VCAN)		+= vcan.o
 obj-$(CONFIG_CAN_DEV)		+= can-dev.o
 can-dev-y			:= dev.o
 
+obj-y				+= usb/
+
 obj-$(CONFIG_CAN_SJA1000)	+= sja1000/
+obj-$(CONFIG_CAN_AT91)		+= at91_can.o
 
 ccflags-$(CONFIG_CAN_DEBUG_DEVICES) := -DDEBUG
diff --git a/drivers/net/can/at91_can.c b/drivers/net/can/at91_can.c
new file mode 100644
index 000000000000..f67ae285a35a
--- /dev/null
+++ b/drivers/net/can/at91_can.c
@@ -0,0 +1,1186 @@
+/*
+ * at91_can.c - CAN network driver for AT91 SoC CAN controller
+ *
+ * (C) 2007 by Hans J. Koch <hjk@linutronix.de>
+ * (C) 2008, 2009 by Marc Kleine-Budde <kernel@pengutronix.de>
+ *
+ * This software may be distributed under the terms of the GNU General
+ * Public License ("GPL") version 2 as distributed in the 'COPYING'
+ * file from the main directory of the linux kernel source.
+ *
+ * Send feedback to <socketcan-users@lists.berlios.de>
+ *
+ *
+ * Your platform definition file should specify something like:
+ *
+ * static struct at91_can_data ek_can_data = {
+ *	transceiver_switch = sam9263ek_transceiver_switch,
+ * };
+ *
+ * at91_add_device_can(&ek_can_data);
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/errno.h>
+#include <linux/if_arp.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/platform_device.h>
+#include <linux/skbuff.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include <linux/can.h>
+#include <linux/can/dev.h>
+#include <linux/can/error.h>
+
+#include <mach/board.h>
+
+#define DRV_NAME		"at91_can"
+#define AT91_NAPI_WEIGHT	12
+
+/*
+ * RX/TX Mailbox split
+ * don't dare to touch
+ */
+#define AT91_MB_RX_NUM		12
+#define AT91_MB_TX_SHIFT	2
+
+#define AT91_MB_RX_FIRST	0
+#define AT91_MB_RX_LAST		(AT91_MB_RX_FIRST + AT91_MB_RX_NUM - 1)
+
+#define AT91_MB_RX_MASK(i)	((1 << (i)) - 1)
+#define AT91_MB_RX_SPLIT	8
+#define AT91_MB_RX_LOW_LAST	(AT91_MB_RX_SPLIT - 1)
+#define AT91_MB_RX_LOW_MASK	(AT91_MB_RX_MASK(AT91_MB_RX_SPLIT))
+
+#define AT91_MB_TX_NUM		(1 << AT91_MB_TX_SHIFT)
+#define AT91_MB_TX_FIRST	(AT91_MB_RX_LAST + 1)
+#define AT91_MB_TX_LAST		(AT91_MB_TX_FIRST + AT91_MB_TX_NUM - 1)
+
+#define AT91_NEXT_PRIO_SHIFT	(AT91_MB_TX_SHIFT)
+#define AT91_NEXT_PRIO_MASK	(0xf << AT91_MB_TX_SHIFT)
+#define AT91_NEXT_MB_MASK	(AT91_MB_TX_NUM - 1)
+#define AT91_NEXT_MASK		((AT91_MB_TX_NUM - 1) | AT91_NEXT_PRIO_MASK)
+
+/* Common registers */
+enum at91_reg {
+	AT91_MR		= 0x000,
+	AT91_IER	= 0x004,
+	AT91_IDR	= 0x008,
+	AT91_IMR	= 0x00C,
+	AT91_SR		= 0x010,
+	AT91_BR		= 0x014,
+	AT91_TIM	= 0x018,
+	AT91_TIMESTP	= 0x01C,
+	AT91_ECR	= 0x020,
+	AT91_TCR	= 0x024,
+	AT91_ACR	= 0x028,
+};
+
+/* Mailbox registers (0 <= i <= 15) */
+#define AT91_MMR(i)		(enum at91_reg)(0x200 + ((i) * 0x20))
+#define AT91_MAM(i)		(enum at91_reg)(0x204 + ((i) * 0x20))
+#define AT91_MID(i)		(enum at91_reg)(0x208 + ((i) * 0x20))
+#define AT91_MFID(i)		(enum at91_reg)(0x20C + ((i) * 0x20))
+#define AT91_MSR(i)		(enum at91_reg)(0x210 + ((i) * 0x20))
+#define AT91_MDL(i)		(enum at91_reg)(0x214 + ((i) * 0x20))
+#define AT91_MDH(i)		(enum at91_reg)(0x218 + ((i) * 0x20))
+#define AT91_MCR(i)		(enum at91_reg)(0x21C + ((i) * 0x20))
+
+/* Register bits */
+#define AT91_MR_CANEN		BIT(0)
+#define AT91_MR_LPM		BIT(1)
+#define AT91_MR_ABM		BIT(2)
+#define AT91_MR_OVL		BIT(3)
+#define AT91_MR_TEOF		BIT(4)
+#define AT91_MR_TTM		BIT(5)
+#define AT91_MR_TIMFRZ		BIT(6)
+#define AT91_MR_DRPT		BIT(7)
+
+#define AT91_SR_RBSY		BIT(29)
+
+#define AT91_MMR_PRIO_SHIFT	(16)
+
+#define AT91_MID_MIDE		BIT(29)
+
+#define AT91_MSR_MRTR		BIT(20)
+#define AT91_MSR_MABT		BIT(22)
+#define AT91_MSR_MRDY		BIT(23)
+#define AT91_MSR_MMI		BIT(24)
+
+#define AT91_MCR_MRTR		BIT(20)
+#define AT91_MCR_MTCR		BIT(23)
+
+/* Mailbox Modes */
+enum at91_mb_mode {
+	AT91_MB_MODE_DISABLED	= 0,
+	AT91_MB_MODE_RX		= 1,
+	AT91_MB_MODE_RX_OVRWR	= 2,
+	AT91_MB_MODE_TX		= 3,
+	AT91_MB_MODE_CONSUMER	= 4,
+	AT91_MB_MODE_PRODUCER	= 5,
+};
+
+/* Interrupt mask bits */
+#define AT91_IRQ_MB_RX		((1 << (AT91_MB_RX_LAST + 1)) \
+				 - (1 << AT91_MB_RX_FIRST))
+#define AT91_IRQ_MB_TX		((1 << (AT91_MB_TX_LAST + 1)) \
+				 - (1 << AT91_MB_TX_FIRST))
+#define AT91_IRQ_MB_ALL		(AT91_IRQ_MB_RX | AT91_IRQ_MB_TX)
+
+#define AT91_IRQ_ERRA		(1 << 16)
+#define AT91_IRQ_WARN		(1 << 17)
+#define AT91_IRQ_ERRP		(1 << 18)
+#define AT91_IRQ_BOFF		(1 << 19)
+#define AT91_IRQ_SLEEP		(1 << 20)
+#define AT91_IRQ_WAKEUP		(1 << 21)
+#define AT91_IRQ_TOVF		(1 << 22)
+#define AT91_IRQ_TSTP		(1 << 23)
+#define AT91_IRQ_CERR		(1 << 24)
+#define AT91_IRQ_SERR		(1 << 25)
+#define AT91_IRQ_AERR		(1 << 26)
+#define AT91_IRQ_FERR		(1 << 27)
+#define AT91_IRQ_BERR		(1 << 28)
+
+#define AT91_IRQ_ERR_ALL	(0x1fff0000)
+#define AT91_IRQ_ERR_FRAME	(AT91_IRQ_CERR | AT91_IRQ_SERR | \
+				 AT91_IRQ_AERR | AT91_IRQ_FERR | AT91_IRQ_BERR)
+#define AT91_IRQ_ERR_LINE	(AT91_IRQ_ERRA | AT91_IRQ_WARN | \
+				 AT91_IRQ_ERRP | AT91_IRQ_BOFF)
+
+#define AT91_IRQ_ALL		(0x1fffffff)
+
+struct at91_priv {
+	struct can_priv		can;	   /* must be the first member! */
+	struct net_device	*dev;
+	struct napi_struct	napi;
+
+	void __iomem		*reg_base;
+
+	u32			reg_sr;
+	unsigned int		tx_next;
+	unsigned int		tx_echo;
+	unsigned int		rx_next;
+
+	struct clk		*clk;
+	struct at91_can_data	*pdata;
+};
+
+static struct can_bittiming_const at91_bittiming_const = {
+	.tseg1_min	= 4,
+	.tseg1_max	= 16,
+	.tseg2_min	= 2,
+	.tseg2_max	= 8,
+	.sjw_max	= 4,
+	.brp_min 	= 2,
+	.brp_max	= 128,
+	.brp_inc	= 1,
+};
+
+static inline int get_tx_next_mb(const struct at91_priv *priv)
+{
+	return (priv->tx_next & AT91_NEXT_MB_MASK) + AT91_MB_TX_FIRST;
+}
+
+static inline int get_tx_next_prio(const struct at91_priv *priv)
+{
+	return (priv->tx_next >> AT91_NEXT_PRIO_SHIFT) & 0xf;
+}
+
+static inline int get_tx_echo_mb(const struct at91_priv *priv)
+{
+	return (priv->tx_echo & AT91_NEXT_MB_MASK) + AT91_MB_TX_FIRST;
+}
+
+static inline u32 at91_read(const struct at91_priv *priv, enum at91_reg reg)
+{
+	return readl(priv->reg_base + reg);
+}
+
+static inline void at91_write(const struct at91_priv *priv, enum at91_reg reg,
+		u32 value)
+{
+	writel(value, priv->reg_base + reg);
+}
+
+static inline void set_mb_mode_prio(const struct at91_priv *priv,
+		unsigned int mb, enum at91_mb_mode mode, int prio)
+{
+	at91_write(priv, AT91_MMR(mb), (mode << 24) | (prio << 16));
+}
+
+static inline void set_mb_mode(const struct at91_priv *priv, unsigned int mb,
+		enum at91_mb_mode mode)
+{
+	set_mb_mode_prio(priv, mb, mode, 0);
+}
+
+static 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));
+	if (unlikely(!skb))
+		return NULL;
+
+	skb->protocol = htons(ETH_P_CAN);
+	skb->ip_summed = CHECKSUM_UNNECESSARY;
+	*cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
+
+	return skb;
+}
+
+static struct sk_buff *alloc_can_err_skb(struct net_device *dev,
+		struct can_frame **cf)
+{
+	struct sk_buff *skb;
+
+	skb = alloc_can_skb(dev, cf);
+	if (unlikely(!skb))
+		return NULL;
+
+	memset(*cf, 0, sizeof(struct can_frame));
+	(*cf)->can_id = CAN_ERR_FLAG;
+	(*cf)->can_dlc = CAN_ERR_DLC;
+
+	return skb;
+}
+
+/*
+ * Swtich transceiver on or off
+ */
+static void at91_transceiver_switch(const struct at91_priv *priv, int on)
+{
+	if (priv->pdata && priv->pdata->transceiver_switch)
+		priv->pdata->transceiver_switch(on);
+}
+
+static void at91_setup_mailboxes(struct net_device *dev)
+{
+	struct at91_priv *priv = netdev_priv(dev);
+	unsigned int i;
+
+	/*
+	 * The first 12 mailboxes are used as a reception FIFO. The
+	 * last mailbox is configured with overwrite option. The
+	 * overwrite flag indicates a FIFO overflow.
+	 */
+	for (i = AT91_MB_RX_FIRST; i < AT91_MB_RX_LAST; i++)
+		set_mb_mode(priv, i, AT91_MB_MODE_RX);
+	set_mb_mode(priv, AT91_MB_RX_LAST, AT91_MB_MODE_RX_OVRWR);
+
+	/* The last 4 mailboxes are used for transmitting. */
+	for (i = AT91_MB_TX_FIRST; i <= AT91_MB_TX_LAST; i++)
+		set_mb_mode_prio(priv, i, AT91_MB_MODE_TX, 0);
+
+	/* Reset tx and rx helper pointers */
+	priv->tx_next = priv->tx_echo = priv->rx_next = 0;
+}
+
+static int at91_set_bittiming(struct net_device *dev)
+{
+	const struct at91_priv *priv = netdev_priv(dev);
+	const struct can_bittiming *bt = &priv->can.bittiming;
+	u32 reg_br;
+
+	reg_br = ((priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) << 24) |
+		((bt->brp - 1) << 16) |	((bt->sjw - 1) << 12) |
+		((bt->prop_seg - 1) << 8) | ((bt->phase_seg1 - 1) << 4) |
+		((bt->phase_seg2 - 1) << 0);
+
+	dev_info(dev->dev.parent, "writing AT91_BR: 0x%08x\n", reg_br);
+
+	at91_write(priv, AT91_BR, reg_br);
+
+	return 0;
+}
+
+static void at91_chip_start(struct net_device *dev)
+{
+	struct at91_priv *priv = netdev_priv(dev);
+	u32 reg_mr, reg_ier;
+
+	/* disable interrupts */
+	at91_write(priv, AT91_IDR, AT91_IRQ_ALL);
+
+	/* disable chip */
+	reg_mr = at91_read(priv, AT91_MR);
+	at91_write(priv, AT91_MR, reg_mr & ~AT91_MR_CANEN);
+
+	at91_setup_mailboxes(dev);
+	at91_transceiver_switch(priv, 1);
+
+	/* enable chip */
+	at91_write(priv, AT91_MR, AT91_MR_CANEN);
+
+	priv->can.state = CAN_STATE_ERROR_ACTIVE;
+
+	/* Enable interrupts */
+	reg_ier = AT91_IRQ_MB_RX | AT91_IRQ_ERRP | AT91_IRQ_ERR_FRAME;
+	at91_write(priv, AT91_IDR, AT91_IRQ_ALL);
+	at91_write(priv, AT91_IER, reg_ier);
+}
+
+static void at91_chip_stop(struct net_device *dev, enum can_state state)
+{
+	struct at91_priv *priv = netdev_priv(dev);
+	u32 reg_mr;
+
+	/* disable interrupts */
+	at91_write(priv, AT91_IDR, AT91_IRQ_ALL);
+
+	reg_mr = at91_read(priv, AT91_MR);
+	at91_write(priv, AT91_MR, reg_mr & ~AT91_MR_CANEN);
+
+	at91_transceiver_switch(priv, 0);
+	priv->can.state = state;
+}
+
+/*
+ * theory of operation:
+ *
+ * According to the datasheet priority 0 is the highest priority, 15
+ * is the lowest. If two mailboxes have the same priority level the
+ * message of the mailbox with the lowest number is sent first.
+ *
+ * We use the first TX mailbox (AT91_MB_TX_FIRST) with prio 0, then
+ * the next mailbox with prio 0, and so on, until all mailboxes are
+ * used. Then we start from the beginning with mailbox
+ * AT91_MB_TX_FIRST, but with prio 1, mailbox AT91_MB_TX_FIRST + 1
+ * prio 1. When we reach the last mailbox with prio 15, we have to
+ * stop sending, waiting for all messages to be delivered, then start
+ * again with mailbox AT91_MB_TX_FIRST prio 0.
+ *
+ * We use the priv->tx_next as counter for the next transmission
+ * mailbox, but without the offset AT91_MB_TX_FIRST. The lower bits
+ * encode the mailbox number, the upper 4 bits the mailbox priority:
+ *
+ * priv->tx_next = (prio << AT91_NEXT_PRIO_SHIFT) ||
+ *                 (mb - AT91_MB_TX_FIRST);
+ *
+ */
+static netdev_tx_t at91_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct at91_priv *priv = netdev_priv(dev);
+	struct net_device_stats *stats = &dev->stats;
+	struct can_frame *cf = (struct can_frame *)skb->data;
+	unsigned int mb, prio;
+	u32 reg_mid, reg_mcr;
+
+	mb = get_tx_next_mb(priv);
+	prio = get_tx_next_prio(priv);
+
+	if (unlikely(!(at91_read(priv, AT91_MSR(mb)) & AT91_MSR_MRDY))) {
+		netif_stop_queue(dev);
+
+		dev_err(dev->dev.parent,
+			"BUG! TX buffer full when queue awake!\n");
+		return NETDEV_TX_BUSY;
+	}
+
+	if (cf->can_id & CAN_EFF_FLAG)
+		reg_mid = (cf->can_id & CAN_EFF_MASK) | AT91_MID_MIDE;
+	else
+		reg_mid = (cf->can_id & CAN_SFF_MASK) << 18;
+
+	reg_mcr = ((cf->can_id & CAN_RTR_FLAG) ? AT91_MCR_MRTR : 0) |
+		(cf->can_dlc << 16) | AT91_MCR_MTCR;
+
+	/* disable MB while writing ID (see datasheet) */
+	set_mb_mode(priv, mb, AT91_MB_MODE_DISABLED);
+	at91_write(priv, AT91_MID(mb), reg_mid);
+	set_mb_mode_prio(priv, mb, AT91_MB_MODE_TX, prio);
+
+	at91_write(priv, AT91_MDL(mb), *(u32 *)(cf->data + 0));
+	at91_write(priv, AT91_MDH(mb), *(u32 *)(cf->data + 4));
+
+	/* This triggers transmission */
+	at91_write(priv, AT91_MCR(mb), reg_mcr);
+
+	stats->tx_bytes += cf->can_dlc;
+	dev->trans_start = jiffies;
+
+	/* _NOTE_: substract AT91_MB_TX_FIRST offset from mb! */
+	can_put_echo_skb(skb, dev, mb - AT91_MB_TX_FIRST);
+
+	/*
+	 * we have to stop the queue and deliver all messages in case
+	 * of a prio+mb counter wrap around. This is the case if
+	 * tx_next buffer prio and mailbox equals 0.
+	 *
+	 * also stop the queue if next buffer is still in use
+	 * (== not ready)
+	 */
+	priv->tx_next++;
+	if (!(at91_read(priv, AT91_MSR(get_tx_next_mb(priv))) &
+	      AT91_MSR_MRDY) ||
+	    (priv->tx_next & AT91_NEXT_MASK) == 0)
+		netif_stop_queue(dev);
+
+	/* Enable interrupt for this mailbox */
+	at91_write(priv, AT91_IER, 1 << mb);
+
+	return NETDEV_TX_OK;
+}
+
+/**
+ * at91_activate_rx_low - activate lower rx mailboxes
+ * @priv: a91 context
+ *
+ * Reenables the lower mailboxes for reception of new CAN messages
+ */
+static inline void at91_activate_rx_low(const struct at91_priv *priv)
+{
+	u32 mask = AT91_MB_RX_LOW_MASK;
+	at91_write(priv, AT91_TCR, mask);
+}
+
+/**
+ * at91_activate_rx_mb - reactive single rx mailbox
+ * @priv: a91 context
+ * @mb: mailbox to reactivate
+ *
+ * Reenables given mailbox for reception of new CAN messages
+ */
+static inline void at91_activate_rx_mb(const struct at91_priv *priv,
+		unsigned int mb)
+{
+	u32 mask = 1 << mb;
+	at91_write(priv, AT91_TCR, mask);
+}
+
+/**
+ * at91_rx_overflow_err - send error frame due to rx overflow
+ * @dev: net device
+ */
+static void at91_rx_overflow_err(struct net_device *dev)
+{
+	struct net_device_stats *stats = &dev->stats;
+	struct sk_buff *skb;
+	struct can_frame *cf;
+
+	dev_dbg(dev->dev.parent, "RX buffer overflow\n");
+	stats->rx_over_errors++;
+	stats->rx_errors++;
+
+	skb = alloc_can_err_skb(dev, &cf);
+	if (unlikely(!skb))
+		return;
+
+	cf->can_id |= CAN_ERR_CRTL;
+	cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
+	netif_receive_skb(skb);
+
+	stats->rx_packets++;
+	stats->rx_bytes += cf->can_dlc;
+}
+
+/**
+ * at91_read_mb - read CAN msg from mailbox (lowlevel impl)
+ * @dev: net device
+ * @mb: mailbox number to read from
+ * @cf: can frame where to store message
+ *
+ * Reads a CAN message from the given mailbox and stores data into
+ * given can frame. "mb" and "cf" must be valid.
+ */
+static void at91_read_mb(struct net_device *dev, unsigned int mb,
+		struct can_frame *cf)
+{
+	const struct at91_priv *priv = netdev_priv(dev);
+	u32 reg_msr, reg_mid;
+
+	reg_mid = at91_read(priv, AT91_MID(mb));
+	if (reg_mid & AT91_MID_MIDE)
+		cf->can_id = ((reg_mid >> 0) & CAN_EFF_MASK) | CAN_EFF_FLAG;
+	else
+		cf->can_id = (reg_mid >> 18) & CAN_SFF_MASK;
+
+	reg_msr = at91_read(priv, AT91_MSR(mb));
+	if (reg_msr & AT91_MSR_MRTR)
+		cf->can_id |= CAN_RTR_FLAG;
+	cf->can_dlc = min_t(__u8, (reg_msr >> 16) & 0xf, 8);
+
+	*(u32 *)(cf->data + 0) = at91_read(priv, AT91_MDL(mb));
+	*(u32 *)(cf->data + 4) = at91_read(priv, AT91_MDH(mb));
+
+	if (unlikely(mb == AT91_MB_RX_LAST && reg_msr & AT91_MSR_MMI))
+		at91_rx_overflow_err(dev);
+}
+
+/**
+ * at91_read_msg - read CAN message from mailbox
+ * @dev: net device
+ * @mb: mail box to read from
+ *
+ * Reads a CAN message from given mailbox, and put into linux network
+ * RX queue, does all housekeeping chores (stats, ...)
+ */
+static void at91_read_msg(struct net_device *dev, unsigned int mb)
+{
+	struct net_device_stats *stats = &dev->stats;
+	struct can_frame *cf;
+	struct sk_buff *skb;
+
+	skb = alloc_can_skb(dev, &cf);
+	if (unlikely(!skb)) {
+		stats->rx_dropped++;
+		return;
+	}
+
+	at91_read_mb(dev, mb, cf);
+	netif_receive_skb(skb);
+
+	stats->rx_packets++;
+	stats->rx_bytes += cf->can_dlc;
+}
+
+/**
+ * at91_poll_rx - read multiple CAN messages from mailboxes
+ * @dev: net device
+ * @quota: max number of pkgs we're allowed to receive
+ *
+ * Theory of Operation:
+ *
+ * 12 of the 16 mailboxes on the chip are reserved for RX. we split
+ * them into 2 groups. The lower group holds 8 and upper 4 mailboxes.
+ *
+ * Like it or not, but the chip always saves a received CAN message
+ * into the first free mailbox it finds (starting with the
+ * lowest). This makes it very difficult to read the messages in the
+ * right order from the chip. This is how we work around that problem:
+ *
+ * The first message goes into mb nr. 0 and issues an interrupt. All
+ * rx ints are disabled in the interrupt handler and a napi poll is
+ * scheduled. We read the mailbox, but do _not_ reenable the mb (to
+ * receive another message).
+ *
+ *    lower mbxs      upper
+ *   ______^______    __^__
+ *  /             \  /     \
+ * +-+-+-+-+-+-+-+-++-+-+-+-+
+ * |x|x|x|x|x|x|x|x|| | | | |
+ * +-+-+-+-+-+-+-+-++-+-+-+-+
+ *  0 0 0 0 0 0  0 0 0 0 1 1  \ mail
+ *  0 1 2 3 4 5  6 7 8 9 0 1  / box
+ *
+ * The variable priv->rx_next points to the next mailbox to read a
+ * message from. As long we're in the lower mailboxes we just read the
+ * mailbox but not reenable it.
+ *
+ * With completion of the last of the lower mailboxes, we reenable the
+ * whole first group, but continue to look for filled mailboxes in the
+ * upper mailboxes. Imagine the second group like overflow mailboxes,
+ * which takes CAN messages if the lower goup is full. While in the
+ * upper group we reenable the mailbox right after reading it. Giving
+ * the chip more room to store messages.
+ *
+ * After finishing we look again in the lower group if we've still
+ * quota.
+ *
+ */
+static int at91_poll_rx(struct net_device *dev, int quota)
+{
+	struct at91_priv *priv = netdev_priv(dev);
+	u32 reg_sr = at91_read(priv, AT91_SR);
+	const unsigned long *addr = (unsigned long *)&reg_sr;
+	unsigned int mb;
+	int received = 0;
+
+	if (priv->rx_next > AT91_MB_RX_LOW_LAST &&
+	    reg_sr & AT91_MB_RX_LOW_MASK)
+		dev_info(dev->dev.parent,
+			 "order of incoming frames cannot be guaranteed\n");
+
+ again:
+	for (mb = find_next_bit(addr, AT91_MB_RX_NUM, priv->rx_next);
+	     mb < AT91_MB_RX_NUM && quota > 0;
+	     reg_sr = at91_read(priv, AT91_SR),
+	     mb = find_next_bit(addr, AT91_MB_RX_NUM, ++priv->rx_next)) {
+		at91_read_msg(dev, mb);
+
+		/* reactivate mailboxes */
+		if (mb == AT91_MB_RX_LOW_LAST)
+			/* all lower mailboxed, if just finished it */
+			at91_activate_rx_low(priv);
+		else if (mb > AT91_MB_RX_LOW_LAST)
+			/* only the mailbox we read */
+			at91_activate_rx_mb(priv, mb);
+
+		received++;
+		quota--;
+	}
+
+	/* upper group completed, look again in lower */
+	if (priv->rx_next > AT91_MB_RX_LOW_LAST &&
+	    quota > 0 && mb >= AT91_MB_RX_NUM) {
+		priv->rx_next = 0;
+		goto again;
+	}
+
+	return received;
+}
+
+static void at91_poll_err_frame(struct net_device *dev,
+		struct can_frame *cf, u32 reg_sr)
+{
+	struct at91_priv *priv = netdev_priv(dev);
+
+	/* CRC error */
+	if (reg_sr & AT91_IRQ_CERR) {
+		dev_dbg(dev->dev.parent, "CERR irq\n");
+		dev->stats.rx_errors++;
+		priv->can.can_stats.bus_error++;
+		cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+	}
+
+	/* Stuffing Error */
+	if (reg_sr & AT91_IRQ_SERR) {
+		dev_dbg(dev->dev.parent, "SERR irq\n");
+		dev->stats.rx_errors++;
+		priv->can.can_stats.bus_error++;
+		cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+		cf->data[2] |= CAN_ERR_PROT_STUFF;
+	}
+
+	/* Acknowledgement Error */
+	if (reg_sr & AT91_IRQ_AERR) {
+		dev_dbg(dev->dev.parent, "AERR irq\n");
+		dev->stats.tx_errors++;
+		cf->can_id |= CAN_ERR_ACK;
+	}
+
+	/* Form error */
+	if (reg_sr & AT91_IRQ_FERR) {
+		dev_dbg(dev->dev.parent, "FERR irq\n");
+		dev->stats.rx_errors++;
+		priv->can.can_stats.bus_error++;
+		cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+		cf->data[2] |= CAN_ERR_PROT_FORM;
+	}
+
+	/* Bit Error */
+	if (reg_sr & AT91_IRQ_BERR) {
+		dev_dbg(dev->dev.parent, "BERR irq\n");
+		dev->stats.tx_errors++;
+		priv->can.can_stats.bus_error++;
+		cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+		cf->data[2] |= CAN_ERR_PROT_BIT;
+	}
+}
+
+static int at91_poll_err(struct net_device *dev, int quota, u32 reg_sr)
+{
+	struct sk_buff *skb;
+	struct can_frame *cf;
+
+	if (quota == 0)
+		return 0;
+
+	skb = alloc_can_err_skb(dev, &cf);
+	if (unlikely(!skb))
+		return 0;
+
+	at91_poll_err_frame(dev, cf, reg_sr);
+	netif_receive_skb(skb);
+
+	dev->last_rx = jiffies;
+	dev->stats.rx_packets++;
+	dev->stats.rx_bytes += cf->can_dlc;
+
+	return 1;
+}
+
+static int at91_poll(struct napi_struct *napi, int quota)
+{
+	struct net_device *dev = napi->dev;
+	const struct at91_priv *priv = netdev_priv(dev);
+	u32 reg_sr = at91_read(priv, AT91_SR);
+	int work_done = 0;
+
+	if (reg_sr & AT91_IRQ_MB_RX)
+		work_done += at91_poll_rx(dev, quota - work_done);
+
+	/*
+	 * The error bits are clear on read,
+	 * so use saved value from irq handler.
+	 */
+	reg_sr |= priv->reg_sr;
+	if (reg_sr & AT91_IRQ_ERR_FRAME)
+		work_done += at91_poll_err(dev, quota - work_done, reg_sr);
+
+	if (work_done < quota) {
+		/* enable IRQs for frame errors and all mailboxes >= rx_next */
+		u32 reg_ier = AT91_IRQ_ERR_FRAME;
+		reg_ier |= AT91_IRQ_MB_RX & ~AT91_MB_RX_MASK(priv->rx_next);
+
+		napi_complete(napi);
+		at91_write(priv, AT91_IER, reg_ier);
+	}
+
+	return work_done;
+}
+
+/*
+ * theory of operation:
+ *
+ * priv->tx_echo holds the number of the oldest can_frame put for
+ * transmission into the hardware, but not yet ACKed by the CAN tx
+ * complete IRQ.
+ *
+ * We iterate from priv->tx_echo to priv->tx_next and check if the
+ * packet has been transmitted, echo it back to the CAN framework. If
+ * we discover a not yet transmitted package, stop looking for more.
+ *
+ */
+static void at91_irq_tx(struct net_device *dev, u32 reg_sr)
+{
+	struct at91_priv *priv = netdev_priv(dev);
+	u32 reg_msr;
+	unsigned int mb;
+
+	/* masking of reg_sr not needed, already done by at91_irq */
+
+	for (/* nix */; (priv->tx_next - priv->tx_echo) > 0; priv->tx_echo++) {
+		mb = get_tx_echo_mb(priv);
+
+		/* no event in mailbox? */
+		if (!(reg_sr & (1 << mb)))
+			break;
+
+		/* Disable irq for this TX mailbox */
+		at91_write(priv, AT91_IDR, 1 << mb);
+
+		/*
+		 * only echo if mailbox signals us a transfer
+		 * complete (MSR_MRDY). Otherwise it's a tansfer
+		 * abort. "can_bus_off()" takes care about the skbs
+		 * parked in the echo queue.
+		 */
+		reg_msr = at91_read(priv, AT91_MSR(mb));
+		if (likely(reg_msr & AT91_MSR_MRDY &&
+			   ~reg_msr & AT91_MSR_MABT)) {
+			/* _NOTE_: substract AT91_MB_TX_FIRST offset from mb! */
+			can_get_echo_skb(dev, mb - AT91_MB_TX_FIRST);
+			dev->stats.tx_packets++;
+		}
+	}
+
+	/*
+	 * restart queue if we don't have a wrap around but restart if
+	 * we get a TX int for the last can frame directly before a
+	 * wrap around.
+	 */
+	if ((priv->tx_next & AT91_NEXT_MASK) != 0 ||
+	    (priv->tx_echo & AT91_NEXT_MASK) == 0)
+		netif_wake_queue(dev);
+}
+
+static void at91_irq_err_state(struct net_device *dev,
+		struct can_frame *cf, enum can_state new_state)
+{
+	struct at91_priv *priv = netdev_priv(dev);
+	u32 reg_idr, reg_ier, reg_ecr;
+	u8 tec, rec;
+
+	reg_ecr = at91_read(priv, AT91_ECR);
+	rec = reg_ecr & 0xff;
+	tec = reg_ecr >> 16;
+
+	switch (priv->can.state) {
+	case CAN_STATE_ERROR_ACTIVE:
+		/*
+		 * from: ERROR_ACTIVE
+		 * to  : ERROR_WARNING, ERROR_PASSIVE, BUS_OFF
+		 * =>  : there was a warning int
+		 */
+		if (new_state >= CAN_STATE_ERROR_WARNING &&
+		    new_state <= CAN_STATE_BUS_OFF) {
+			dev_dbg(dev->dev.parent, "Error Warning IRQ\n");
+			priv->can.can_stats.error_warning++;
+
+			cf->can_id |= CAN_ERR_CRTL;
+			cf->data[1] = (tec > rec) ?
+				CAN_ERR_CRTL_TX_WARNING :
+				CAN_ERR_CRTL_RX_WARNING;
+		}
+	case CAN_STATE_ERROR_WARNING:	/* fallthrough */
+		/*
+		 * from: ERROR_ACTIVE, ERROR_WARNING
+		 * to  : ERROR_PASSIVE, BUS_OFF
+		 * =>  : error passive int
+		 */
+		if (new_state >= CAN_STATE_ERROR_PASSIVE &&
+		    new_state <= CAN_STATE_BUS_OFF) {
+			dev_dbg(dev->dev.parent, "Error Passive IRQ\n");
+			priv->can.can_stats.error_passive++;
+
+			cf->can_id |= CAN_ERR_CRTL;
+			cf->data[1] = (tec > rec) ?
+				CAN_ERR_CRTL_TX_PASSIVE :
+				CAN_ERR_CRTL_RX_PASSIVE;
+		}
+		break;
+	case CAN_STATE_BUS_OFF:
+		/*
+		 * from: BUS_OFF
+		 * to  : ERROR_ACTIVE, ERROR_WARNING, ERROR_PASSIVE
+		 */
+		if (new_state <= CAN_STATE_ERROR_PASSIVE) {
+			cf->can_id |= CAN_ERR_RESTARTED;
+
+			dev_dbg(dev->dev.parent, "restarted\n");
+			priv->can.can_stats.restarts++;
+
+			netif_carrier_on(dev);
+			netif_wake_queue(dev);
+		}
+		break;
+	default:
+		break;
+	}
+
+
+	/* process state changes depending on the new state */
+	switch (new_state) {
+	case CAN_STATE_ERROR_ACTIVE:
+		/*
+		 * actually we want to enable AT91_IRQ_WARN here, but
+		 * it screws up the system under certain
+		 * circumstances. so just enable AT91_IRQ_ERRP, thus
+		 * the "fallthrough"
+		 */
+		dev_dbg(dev->dev.parent, "Error Active\n");
+		cf->can_id |= CAN_ERR_PROT;
+		cf->data[2] = CAN_ERR_PROT_ACTIVE;
+	case CAN_STATE_ERROR_WARNING:	/* fallthrough */
+		reg_idr = AT91_IRQ_ERRA | AT91_IRQ_WARN | AT91_IRQ_BOFF;
+		reg_ier = AT91_IRQ_ERRP;
+		break;
+	case CAN_STATE_ERROR_PASSIVE:
+		reg_idr = AT91_IRQ_ERRA | AT91_IRQ_WARN | AT91_IRQ_ERRP;
+		reg_ier = AT91_IRQ_BOFF;
+		break;
+	case CAN_STATE_BUS_OFF:
+		reg_idr = AT91_IRQ_ERRA | AT91_IRQ_ERRP |
+			AT91_IRQ_WARN | AT91_IRQ_BOFF;
+		reg_ier = 0;
+
+		cf->can_id |= CAN_ERR_BUSOFF;
+
+		dev_dbg(dev->dev.parent, "bus-off\n");
+		netif_carrier_off(dev);
+		priv->can.can_stats.bus_off++;
+
+		/* turn off chip, if restart is disabled */
+		if (!priv->can.restart_ms) {
+			at91_chip_stop(dev, CAN_STATE_BUS_OFF);
+			return;
+		}
+		break;
+	default:
+		break;
+	}
+
+	at91_write(priv, AT91_IDR, reg_idr);
+	at91_write(priv, AT91_IER, reg_ier);
+}
+
+static void at91_irq_err(struct net_device *dev)
+{
+	struct at91_priv *priv = netdev_priv(dev);
+	struct sk_buff *skb;
+	struct can_frame *cf;
+	enum can_state new_state;
+	u32 reg_sr;
+
+	reg_sr = at91_read(priv, AT91_SR);
+
+	/* we need to look at the unmasked reg_sr */
+	if (unlikely(reg_sr & AT91_IRQ_BOFF))
+		new_state = CAN_STATE_BUS_OFF;
+	else if (unlikely(reg_sr & AT91_IRQ_ERRP))
+		new_state = CAN_STATE_ERROR_PASSIVE;
+	else if (unlikely(reg_sr & AT91_IRQ_WARN))
+		new_state = CAN_STATE_ERROR_WARNING;
+	else if (likely(reg_sr & AT91_IRQ_ERRA))
+		new_state = CAN_STATE_ERROR_ACTIVE;
+	else {
+		dev_err(dev->dev.parent, "BUG! hardware in undefined state\n");
+		return;
+	}
+
+	/* state hasn't changed */
+	if (likely(new_state == priv->can.state))
+		return;
+
+	skb = alloc_can_err_skb(dev, &cf);
+	if (unlikely(!skb))
+		return;
+
+	at91_irq_err_state(dev, cf, new_state);
+	netif_rx(skb);
+
+	dev->last_rx = jiffies;
+	dev->stats.rx_packets++;
+	dev->stats.rx_bytes += cf->can_dlc;
+
+	priv->can.state = new_state;
+}
+
+/*
+ * interrupt handler
+ */
+static irqreturn_t at91_irq(int irq, void *dev_id)
+{
+	struct net_device *dev = dev_id;
+	struct at91_priv *priv = netdev_priv(dev);
+	irqreturn_t handled = IRQ_NONE;
+	u32 reg_sr, reg_imr;
+
+	reg_sr = at91_read(priv, AT91_SR);
+	reg_imr = at91_read(priv, AT91_IMR);
+
+	/* Ignore masked interrupts */
+	reg_sr &= reg_imr;
+	if (!reg_sr)
+		goto exit;
+
+	handled = IRQ_HANDLED;
+
+	/* Receive or error interrupt? -> napi */
+	if (reg_sr & (AT91_IRQ_MB_RX | AT91_IRQ_ERR_FRAME)) {
+		/*
+		 * The error bits are clear on read,
+		 * save for later use.
+		 */
+		priv->reg_sr = reg_sr;
+		at91_write(priv, AT91_IDR,
+			   AT91_IRQ_MB_RX | AT91_IRQ_ERR_FRAME);
+		napi_schedule(&priv->napi);
+	}
+
+	/* Transmission complete interrupt */
+	if (reg_sr & AT91_IRQ_MB_TX)
+		at91_irq_tx(dev, reg_sr);
+
+	at91_irq_err(dev);
+
+ exit:
+	return handled;
+}
+
+static int at91_open(struct net_device *dev)
+{
+	struct at91_priv *priv = netdev_priv(dev);
+	int err;
+
+	clk_enable(priv->clk);
+
+	/* check or determine and set bittime */
+	err = open_candev(dev);
+	if (err)
+		goto out;
+
+	/* register interrupt handler */
+	if (request_irq(dev->irq, at91_irq, IRQF_SHARED,
+			dev->name, dev)) {
+		err = -EAGAIN;
+		goto out_close;
+	}
+
+	/* start chip and queuing */
+	at91_chip_start(dev);
+	napi_enable(&priv->napi);
+	netif_start_queue(dev);
+
+	return 0;
+
+ out_close:
+	close_candev(dev);
+ out:
+	clk_disable(priv->clk);
+
+	return err;
+}
+
+/*
+ * stop CAN bus activity
+ */
+static int at91_close(struct net_device *dev)
+{
+	struct at91_priv *priv = netdev_priv(dev);
+
+	netif_stop_queue(dev);
+	napi_disable(&priv->napi);
+	at91_chip_stop(dev, CAN_STATE_STOPPED);
+
+	free_irq(dev->irq, dev);
+	clk_disable(priv->clk);
+
+	close_candev(dev);
+
+	return 0;
+}
+
+static int at91_set_mode(struct net_device *dev, enum can_mode mode)
+{
+	switch (mode) {
+	case CAN_MODE_START:
+		at91_chip_start(dev);
+		netif_wake_queue(dev);
+		break;
+
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+static const struct net_device_ops at91_netdev_ops = {
+	.ndo_open	= at91_open,
+	.ndo_stop	= at91_close,
+	.ndo_start_xmit	= at91_start_xmit,
+};
+
+static int __init at91_can_probe(struct platform_device *pdev)
+{
+	struct net_device *dev;
+	struct at91_priv *priv;
+	struct resource *res;
+	struct clk *clk;
+	void __iomem *addr;
+	int err, irq;
+
+	clk = clk_get(&pdev->dev, "can_clk");
+	if (IS_ERR(clk)) {
+		dev_err(&pdev->dev, "no clock defined\n");
+		err = -ENODEV;
+		goto exit;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	irq = platform_get_irq(pdev, 0);
+	if (!res || !irq) {
+		err = -ENODEV;
+		goto exit_put;
+	}
+
+	if (!request_mem_region(res->start,
+				resource_size(res),
+				pdev->name)) {
+		err = -EBUSY;
+		goto exit_put;
+	}
+
+	addr = ioremap_nocache(res->start, resource_size(res));
+	if (!addr) {
+		err = -ENOMEM;
+		goto exit_release;
+	}
+
+	dev = alloc_candev(sizeof(struct at91_priv));
+	if (!dev) {
+		err = -ENOMEM;
+		goto exit_iounmap;
+	}
+
+	dev->netdev_ops	= &at91_netdev_ops;
+	dev->irq = irq;
+	dev->flags |= IFF_ECHO;
+
+	priv = netdev_priv(dev);
+	priv->can.clock.freq = clk_get_rate(clk);
+	priv->can.bittiming_const = &at91_bittiming_const;
+	priv->can.do_set_bittiming = at91_set_bittiming;
+	priv->can.do_set_mode = at91_set_mode;
+	priv->reg_base = addr;
+	priv->dev = dev;
+	priv->clk = clk;
+	priv->pdata = pdev->dev.platform_data;
+
+	netif_napi_add(dev, &priv->napi, at91_poll, AT91_NAPI_WEIGHT);
+
+	dev_set_drvdata(&pdev->dev, dev);
+	SET_NETDEV_DEV(dev, &pdev->dev);
+
+	err = register_candev(dev);
+	if (err) {
+		dev_err(&pdev->dev, "registering netdev failed\n");
+		goto exit_free;
+	}
+
+	dev_info(&pdev->dev, "device registered (reg_base=%p, irq=%d)\n",
+		 priv->reg_base, dev->irq);
+
+	return 0;
+
+ exit_free:
+	free_netdev(dev);
+ exit_iounmap:
+	iounmap(addr);
+ exit_release:
+	release_mem_region(res->start, resource_size(res));
+ exit_put:
+	clk_put(clk);
+ exit:
+	return err;
+}
+
+static int __devexit at91_can_remove(struct platform_device *pdev)
+{
+	struct net_device *dev = platform_get_drvdata(pdev);
+	struct at91_priv *priv = netdev_priv(dev);
+	struct resource *res;
+
+	unregister_netdev(dev);
+
+	platform_set_drvdata(pdev, NULL);
+
+	free_netdev(dev);
+
+	iounmap(priv->reg_base);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	release_mem_region(res->start, resource_size(res));
+
+	clk_put(priv->clk);
+
+	return 0;
+}
+
+static struct platform_driver at91_can_driver = {
+	.probe		= at91_can_probe,
+	.remove		= __devexit_p(at91_can_remove),
+	.driver		= {
+		.name	= DRV_NAME,
+		.owner	= THIS_MODULE,
+	},
+};
+
+static int __init at91_can_module_init(void)
+{
+	printk(KERN_INFO "%s netdevice driver\n", DRV_NAME);
+	return platform_driver_register(&at91_can_driver);
+}
+
+static void __exit at91_can_module_exit(void)
+{
+	platform_driver_unregister(&at91_can_driver);
+	printk(KERN_INFO "%s: driver removed\n", DRV_NAME);
+}
+
+module_init(at91_can_module_init);
+module_exit(at91_can_module_exit);
+
+MODULE_AUTHOR("Marc Kleine-Budde <mkl@pengutronix.de>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION(DRV_NAME " CAN netdevice driver");
diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
index f0b9a1e1db46..2868fe842a41 100644
--- a/drivers/net/can/dev.c
+++ b/drivers/net/can/dev.c
@@ -589,6 +589,22 @@ static int can_changelink(struct net_device *dev,
 	return 0;
 }
 
+static size_t can_get_size(const struct net_device *dev)
+{
+	struct can_priv *priv = netdev_priv(dev);
+	size_t size;
+
+	size = nla_total_size(sizeof(u32));   /* IFLA_CAN_STATE */
+	size += sizeof(struct can_ctrlmode);  /* IFLA_CAN_CTRLMODE */
+	size += nla_total_size(sizeof(u32));  /* IFLA_CAN_RESTART_MS */
+	size += sizeof(struct can_bittiming); /* IFLA_CAN_BITTIMING */
+	size += sizeof(struct can_clock);     /* IFLA_CAN_CLOCK */
+	if (priv->bittiming_const)	      /* IFLA_CAN_BITTIMING_CONST */
+		size += sizeof(struct can_bittiming_const);
+
+	return size;
+}
+
 static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
 {
 	struct can_priv *priv = netdev_priv(dev);
@@ -613,6 +629,11 @@ nla_put_failure:
 	return -EMSGSIZE;
 }
 
+static size_t can_get_xstats_size(const struct net_device *dev)
+{
+	return sizeof(struct can_device_stats);
+}
+
 static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev)
 {
 	struct can_priv *priv = netdev_priv(dev);
@@ -639,7 +660,9 @@ static struct rtnl_link_ops can_link_ops __read_mostly = {
 	.setup		= can_setup,
 	.newlink	= can_newlink,
 	.changelink	= can_changelink,
+	.get_size	= can_get_size,
 	.fill_info	= can_fill_info,
+	.get_xstats_size = can_get_xstats_size,
 	.fill_xstats	= can_fill_xstats,
 };
 
diff --git a/drivers/net/can/sja1000/Kconfig b/drivers/net/can/sja1000/Kconfig
new file mode 100644
index 000000000000..4c674927f247
--- /dev/null
+++ b/drivers/net/can/sja1000/Kconfig
@@ -0,0 +1,47 @@
+menuconfig CAN_SJA1000
+	tristate "Philips/NXP SJA1000 devices"
+	depends on CAN_DEV && HAS_IOMEM
+
+if CAN_SJA1000
+
+config CAN_SJA1000_ISA
+	tristate "ISA Bus based legacy SJA1000 driver"
+	depends on ISA
+	---help---
+	  This driver adds legacy support for SJA1000 chips connected to
+	  the ISA bus using I/O port, memory mapped or indirect access.
+
+config CAN_SJA1000_PLATFORM
+	tristate "Generic Platform Bus based SJA1000 driver"
+	---help---
+	  This driver adds support for the SJA1000 chips connected to
+	  the "platform bus" (Linux abstraction for directly to the
+	  processor attached devices).  Which can be found on various
+	  boards from Phytec (http://www.phytec.de) like the PCM027,
+	  PCM038.
+
+config CAN_SJA1000_OF_PLATFORM
+	tristate "Generic OF Platform Bus based SJA1000 driver"
+	depends on PPC_OF
+	---help---
+	  This driver adds support for the SJA1000 chips connected to
+	  the OpenFirmware "platform bus" found on embedded systems with
+	  OpenFirmware bindings, e.g. if you have a PowerPC based system
+	  you may want to enable this option.
+
+config CAN_EMS_PCI
+	tristate "EMS CPC-PCI, CPC-PCIe and CPC-104P Card"
+	depends on PCI
+	---help---
+	  This driver is for the one, two or four channel CPC-PCI,
+	  CPC-PCIe and CPC-104P cards from EMS Dr. Thomas Wuensche
+	  (http://www.ems-wuensche.de).
+
+config CAN_KVASER_PCI
+	tristate "Kvaser PCIcanx and Kvaser PCIcan PCI Cards"
+	depends on PCI
+	---help---
+	  This driver is for the the PCIcanx and PCIcan cards (1, 2 or
+	  4 channel) from Kvaser (http://www.kvaser.com).
+
+endif
diff --git a/drivers/net/can/sja1000/ems_pci.c b/drivers/net/can/sja1000/ems_pci.c
index 7d84b8ac9c1c..fd04789d3370 100644
--- a/drivers/net/can/sja1000/ems_pci.c
+++ b/drivers/net/can/sja1000/ems_pci.c
@@ -94,12 +94,14 @@ struct ems_pci_card {
 #define EMS_PCI_CDR             (CDR_CBP | CDR_CLKOUT_MASK)
 
 #define EMS_PCI_V1_BASE_BAR     1
-#define EMS_PCI_V1_MEM_SIZE     4096
+#define EMS_PCI_V1_CONF_SIZE    4096 /* size of PITA control area */
 #define EMS_PCI_V2_BASE_BAR     2
-#define EMS_PCI_V2_MEM_SIZE     128
+#define EMS_PCI_V2_CONF_SIZE    128 /* size of PLX control area */
 #define EMS_PCI_CAN_BASE_OFFSET 0x400 /* offset where the controllers starts */
 #define EMS_PCI_CAN_CTRL_SIZE   0x200 /* memory size for each controller */
 
+#define EMS_PCI_BASE_SIZE  4096 /* size of controller area */
+
 static struct pci_device_id ems_pci_tbl[] = {
 	/* CPC-PCI v1 */
 	{PCI_VENDOR_ID_SIEMENS, 0x2104, PCI_ANY_ID, PCI_ANY_ID,},
@@ -224,7 +226,7 @@ static int __devinit ems_pci_add_card(struct pci_dev *pdev,
 	struct sja1000_priv *priv;
 	struct net_device *dev;
 	struct ems_pci_card *card;
-	int max_chan, mem_size, base_bar;
+	int max_chan, conf_size, base_bar;
 	int err, i;
 
 	/* Enabling PCI device */
@@ -251,22 +253,22 @@ static int __devinit ems_pci_add_card(struct pci_dev *pdev,
 		card->version = 2; /* CPC-PCI v2 */
 		max_chan = EMS_PCI_V2_MAX_CHAN;
 		base_bar = EMS_PCI_V2_BASE_BAR;
-		mem_size = EMS_PCI_V2_MEM_SIZE;
+		conf_size = EMS_PCI_V2_CONF_SIZE;
 	} else {
 		card->version = 1; /* CPC-PCI v1 */
 		max_chan = EMS_PCI_V1_MAX_CHAN;
 		base_bar = EMS_PCI_V1_BASE_BAR;
-		mem_size = EMS_PCI_V1_MEM_SIZE;
+		conf_size = EMS_PCI_V1_CONF_SIZE;
 	}
 
 	/* Remap configuration space and controller memory area */
-	card->conf_addr = pci_iomap(pdev, 0, mem_size);
+	card->conf_addr = pci_iomap(pdev, 0, conf_size);
 	if (card->conf_addr == NULL) {
 		err = -ENOMEM;
 		goto failure_cleanup;
 	}
 
-	card->base_addr = pci_iomap(pdev, base_bar, mem_size);
+	card->base_addr = pci_iomap(pdev, base_bar, EMS_PCI_BASE_SIZE);
 	if (card->base_addr == NULL) {
 		err = -ENOMEM;
 		goto failure_cleanup;
diff --git a/drivers/net/can/sja1000/sja1000_of_platform.c b/drivers/net/can/sja1000/sja1000_of_platform.c
index 3373560405ba..9dd076a626a5 100644
--- a/drivers/net/can/sja1000/sja1000_of_platform.c
+++ b/drivers/net/can/sja1000/sja1000_of_platform.c
@@ -213,6 +213,7 @@ static struct of_device_id __devinitdata sja1000_ofp_table[] = {
 	{.compatible = "nxp,sja1000"},
 	{},
 };
+MODULE_DEVICE_TABLE(of, sja1000_ofp_table);
 
 static struct of_platform_driver sja1000_ofp_driver = {
 	.owner = THIS_MODULE,
diff --git a/drivers/net/can/usb/Kconfig b/drivers/net/can/usb/Kconfig
new file mode 100644
index 000000000000..bbc78e0b8a15
--- /dev/null
+++ b/drivers/net/can/usb/Kconfig
@@ -0,0 +1,10 @@
+menu "CAN USB interfaces"
+	depends on USB && CAN_DEV
+
+config CAN_EMS_USB
+	tristate "EMS CPC-USB/ARM7 CAN/USB interface"
+	---help---
+	  This driver is for the one channel CPC-USB/ARM7 CAN/USB interface
+	  from from EMS Dr. Thomas Wuensche (http://www.ems-wuensche.de).
+
+endmenu
diff --git a/drivers/net/can/usb/Makefile b/drivers/net/can/usb/Makefile
new file mode 100644
index 000000000000..0afd51d4c7a5
--- /dev/null
+++ b/drivers/net/can/usb/Makefile
@@ -0,0 +1,7 @@
+#
+#  Makefile for the Linux Controller Area Network USB drivers.
+#
+
+obj-$(CONFIG_CAN_EMS_USB) += ems_usb.o
+
+ccflags-$(CONFIG_CAN_DEBUG_DEVICES) := -DDEBUG
diff --git a/drivers/net/can/usb/ems_usb.c b/drivers/net/can/usb/ems_usb.c
new file mode 100644
index 000000000000..abdbd9c2b788
--- /dev/null
+++ b/drivers/net/can/usb/ems_usb.c
@@ -0,0 +1,1158 @@
+/*
+ * CAN driver for EMS Dr. Thomas Wuensche CPC-USB/ARM7
+ *
+ * Copyright (C) 2004-2009 EMS Dr. Thomas Wuensche
+ *
+ * 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; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+#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>
+
+MODULE_AUTHOR("Sebastian Haas <haas@ems-wuensche.com>");
+MODULE_DESCRIPTION("CAN driver for EMS Dr. Thomas Wuensche CAN/USB interfaces");
+MODULE_LICENSE("GPL v2");
+
+/* Control-Values for CPC_Control() Command Subject Selection */
+#define CONTR_CAN_MESSAGE 0x04
+#define CONTR_CAN_STATE   0x0C
+#define CONTR_BUS_ERROR   0x1C
+
+/* Control Command Actions */
+#define CONTR_CONT_OFF 0
+#define CONTR_CONT_ON  1
+#define CONTR_ONCE     2
+
+/* Messages from CPC to PC */
+#define CPC_MSG_TYPE_CAN_FRAME       1  /* CAN data frame */
+#define CPC_MSG_TYPE_RTR_FRAME       8  /* CAN remote frame */
+#define CPC_MSG_TYPE_CAN_PARAMS      12 /* Actual CAN parameters */
+#define CPC_MSG_TYPE_CAN_STATE       14 /* CAN state message */
+#define CPC_MSG_TYPE_EXT_CAN_FRAME   16 /* Extended CAN data frame */
+#define CPC_MSG_TYPE_EXT_RTR_FRAME   17 /* Extended remote frame */
+#define CPC_MSG_TYPE_CONTROL         19 /* change interface behavior */
+#define CPC_MSG_TYPE_CONFIRM         20 /* command processed confirmation */
+#define CPC_MSG_TYPE_OVERRUN         21 /* overrun events */
+#define CPC_MSG_TYPE_CAN_FRAME_ERROR 23 /* detected bus errors */
+#define CPC_MSG_TYPE_ERR_COUNTER     25 /* RX/TX error counter */
+
+/* Messages from the PC to the CPC interface  */
+#define CPC_CMD_TYPE_CAN_FRAME     1   /* CAN data frame */
+#define CPC_CMD_TYPE_CONTROL       3   /* control of interface behavior */
+#define CPC_CMD_TYPE_CAN_PARAMS    6   /* set CAN parameters */
+#define CPC_CMD_TYPE_RTR_FRAME     13  /* CAN remote frame */
+#define CPC_CMD_TYPE_CAN_STATE     14  /* CAN state message */
+#define CPC_CMD_TYPE_EXT_CAN_FRAME 15  /* Extended CAN data frame */
+#define CPC_CMD_TYPE_EXT_RTR_FRAME 16  /* Extended CAN remote frame */
+#define CPC_CMD_TYPE_CAN_EXIT      200 /* exit the CAN */
+
+#define CPC_CMD_TYPE_INQ_ERR_COUNTER 25 /* request the CAN error counters */
+#define CPC_CMD_TYPE_CLEAR_MSG_QUEUE 8  /* clear CPC_MSG queue */
+#define CPC_CMD_TYPE_CLEAR_CMD_QUEUE 28 /* clear CPC_CMD queue */
+
+#define CPC_CC_TYPE_SJA1000 2 /* Philips basic CAN controller */
+
+#define CPC_CAN_ECODE_ERRFRAME 0x01 /* Ecode type */
+
+/* Overrun types */
+#define CPC_OVR_EVENT_CAN       0x01
+#define CPC_OVR_EVENT_CANSTATE  0x02
+#define CPC_OVR_EVENT_BUSERROR  0x04
+
+/*
+ * If the CAN controller lost a message we indicate it with the highest bit
+ * set in the count field.
+ */
+#define CPC_OVR_HW 0x80
+
+/* Size of the "struct ems_cpc_msg" without the union */
+#define CPC_MSG_HEADER_LEN   11
+#define CPC_CAN_MSG_MIN_SIZE 5
+
+/* Define these values to match your devices */
+#define USB_CPCUSB_VENDOR_ID 0x12D6
+
+#define USB_CPCUSB_ARM7_PRODUCT_ID 0x0444
+
+/* Mode register NXP LPC2119/SJA1000 CAN Controller */
+#define SJA1000_MOD_NORMAL 0x00
+#define SJA1000_MOD_RM     0x01
+
+/* ECC register NXP LPC2119/SJA1000 CAN Controller */
+#define SJA1000_ECC_SEG   0x1F
+#define SJA1000_ECC_DIR   0x20
+#define SJA1000_ECC_ERR   0x06
+#define SJA1000_ECC_BIT   0x00
+#define SJA1000_ECC_FORM  0x40
+#define SJA1000_ECC_STUFF 0x80
+#define SJA1000_ECC_MASK  0xc0
+
+/* Status register content */
+#define SJA1000_SR_BS 0x80
+#define SJA1000_SR_ES 0x40
+
+#define SJA1000_DEFAULT_OUTPUT_CONTROL 0xDA
+
+/*
+ * The device actually uses a 16MHz clock to generate the CAN clock
+ * but it expects SJA1000 bit settings based on 8MHz (is internally
+ * converted).
+ */
+#define EMS_USB_ARM7_CLOCK 8000000
+
+/*
+ * CAN-Message representation in a CPC_MSG. Message object type is
+ * CPC_MSG_TYPE_CAN_FRAME or CPC_MSG_TYPE_RTR_FRAME or
+ * CPC_MSG_TYPE_EXT_CAN_FRAME or CPC_MSG_TYPE_EXT_RTR_FRAME.
+ */
+struct cpc_can_msg {
+	u32 id;
+	u8 length;
+	u8 msg[8];
+};
+
+/* Representation of the CAN parameters for the SJA1000 controller */
+struct cpc_sja1000_params {
+	u8 mode;
+	u8 acc_code0;
+	u8 acc_code1;
+	u8 acc_code2;
+	u8 acc_code3;
+	u8 acc_mask0;
+	u8 acc_mask1;
+	u8 acc_mask2;
+	u8 acc_mask3;
+	u8 btr0;
+	u8 btr1;
+	u8 outp_contr;
+};
+
+/* CAN params message representation */
+struct cpc_can_params {
+	u8 cc_type;
+
+	/* Will support M16C CAN controller in the future */
+	union {
+		struct cpc_sja1000_params sja1000;
+	} cc_params;
+};
+
+/* Structure for confirmed message handling */
+struct cpc_confirm {
+	u8 error; /* error code */
+};
+
+/* Structure for overrun conditions */
+struct cpc_overrun {
+	u8 event;
+	u8 count;
+};
+
+/* SJA1000 CAN errors (compatible to NXP LPC2119) */
+struct cpc_sja1000_can_error {
+	u8 ecc;
+	u8 rxerr;
+	u8 txerr;
+};
+
+/* structure for CAN error conditions */
+struct cpc_can_error {
+	u8 ecode;
+
+	struct {
+		u8 cc_type;
+
+		/* Other controllers may also provide error code capture regs */
+		union {
+			struct cpc_sja1000_can_error sja1000;
+		} regs;
+	} cc;
+};
+
+/*
+ * Structure containing RX/TX error counter. This structure is used to request
+ * the values of the CAN controllers TX and RX error counter.
+ */
+struct cpc_can_err_counter {
+	u8 rx;
+	u8 tx;
+};
+
+/* Main message type used between library and application */
+struct __attribute__ ((packed)) ems_cpc_msg {
+	u8 type;	/* type of message */
+	u8 length;	/* length of data within union 'msg' */
+	u8 msgid;	/* confirmation handle */
+	u32 ts_sec;	/* timestamp in seconds */
+	u32 ts_nsec;	/* timestamp in nano seconds */
+
+	union {
+		u8 generic[64];
+		struct cpc_can_msg can_msg;
+		struct cpc_can_params can_params;
+		struct cpc_confirm confirmation;
+		struct cpc_overrun overrun;
+		struct cpc_can_error error;
+		struct cpc_can_err_counter err_counter;
+		u8 can_state;
+	} msg;
+};
+
+/*
+ * Table of devices that work with this driver
+ * NOTE: This driver supports only CPC-USB/ARM7 (LPC2119) yet.
+ */
+static struct usb_device_id ems_usb_table[] = {
+	{USB_DEVICE(USB_CPCUSB_VENDOR_ID, USB_CPCUSB_ARM7_PRODUCT_ID)},
+	{} /* Terminating entry */
+};
+
+MODULE_DEVICE_TABLE(usb, ems_usb_table);
+
+#define RX_BUFFER_SIZE      64
+#define CPC_HEADER_SIZE     4
+#define INTR_IN_BUFFER_SIZE 4
+
+#define MAX_RX_URBS 10
+#define MAX_TX_URBS CAN_ECHO_SKB_MAX
+
+struct ems_usb;
+
+struct ems_tx_urb_context {
+	struct ems_usb *dev;
+
+	u32 echo_index;
+	u8 dlc;
+};
+
+struct ems_usb {
+	struct can_priv can; /* must be the first member */
+	int open_time;
+
+	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 ems_tx_urb_context tx_contexts[MAX_TX_URBS];
+
+	struct usb_anchor rx_submitted;
+
+	struct urb *intr_urb;
+
+	u8 *tx_msg_buffer;
+
+	u8 *intr_in_buffer;
+	unsigned int free_slots; /* remember number of available slots */
+
+	struct ems_cpc_msg active_params; /* active controller parameters */
+};
+
+static void ems_usb_read_interrupt_callback(struct urb *urb)
+{
+	struct ems_usb *dev = urb->context;
+	struct net_device *netdev = dev->netdev;
+	int err;
+
+	if (!netif_device_present(netdev))
+		return;
+
+	switch (urb->status) {
+	case 0:
+		dev->free_slots = dev->intr_in_buffer[1];
+		break;
+
+	case -ECONNRESET: /* unlink */
+	case -ENOENT:
+	case -ESHUTDOWN:
+		return;
+
+	default:
+		dev_info(netdev->dev.parent, "Rx interrupt aborted %d\n",
+			 urb->status);
+		break;
+	}
+
+	err = usb_submit_urb(urb, GFP_ATOMIC);
+
+	if (err == -ENODEV)
+		netif_device_detach(netdev);
+	else if (err)
+		dev_err(netdev->dev.parent,
+			"failed resubmitting intr urb: %d\n", err);
+
+	return;
+}
+
+static void ems_usb_rx_can_msg(struct ems_usb *dev, struct ems_cpc_msg *msg)
+{
+	struct can_frame *cf;
+	struct sk_buff *skb;
+	int i;
+	struct net_device_stats *stats = &dev->netdev->stats;
+
+	skb = netdev_alloc_skb(dev->netdev, sizeof(struct can_frame));
+	if (skb == NULL)
+		return;
+
+	skb->protocol = htons(ETH_P_CAN);
+
+	cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
+
+	cf->can_id = le32_to_cpu(msg->msg.can_msg.id);
+	cf->can_dlc = min_t(u8, msg->msg.can_msg.length, 8);
+
+	if (msg->type == CPC_MSG_TYPE_EXT_CAN_FRAME
+	    || msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME)
+		cf->can_id |= CAN_EFF_FLAG;
+
+	if (msg->type == CPC_MSG_TYPE_RTR_FRAME
+	    || msg->type == CPC_MSG_TYPE_EXT_RTR_FRAME) {
+		cf->can_id |= CAN_RTR_FLAG;
+	} else {
+		for (i = 0; i < cf->can_dlc; i++)
+			cf->data[i] = msg->msg.can_msg.msg[i];
+	}
+
+	netif_rx(skb);
+
+	stats->rx_packets++;
+	stats->rx_bytes += cf->can_dlc;
+}
+
+static void ems_usb_rx_err(struct ems_usb *dev, struct ems_cpc_msg *msg)
+{
+	struct can_frame *cf;
+	struct sk_buff *skb;
+	struct net_device_stats *stats = &dev->netdev->stats;
+
+	skb = netdev_alloc_skb(dev->netdev, sizeof(struct can_frame));
+	if (skb == NULL)
+		return;
+
+	skb->protocol = htons(ETH_P_CAN);
+
+	cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
+	memset(cf, 0, sizeof(struct can_frame));
+
+	cf->can_id = CAN_ERR_FLAG;
+	cf->can_dlc = CAN_ERR_DLC;
+
+	if (msg->type == CPC_MSG_TYPE_CAN_STATE) {
+		u8 state = msg->msg.can_state;
+
+		if (state & SJA1000_SR_BS) {
+			dev->can.state = CAN_STATE_BUS_OFF;
+			cf->can_id |= CAN_ERR_BUSOFF;
+
+			can_bus_off(dev->netdev);
+		} else if (state & SJA1000_SR_ES) {
+			dev->can.state = CAN_STATE_ERROR_WARNING;
+			dev->can.can_stats.error_warning++;
+		} else {
+			dev->can.state = CAN_STATE_ERROR_ACTIVE;
+			dev->can.can_stats.error_passive++;
+		}
+	} else if (msg->type == CPC_MSG_TYPE_CAN_FRAME_ERROR) {
+		u8 ecc = msg->msg.error.cc.regs.sja1000.ecc;
+		u8 txerr = msg->msg.error.cc.regs.sja1000.txerr;
+		u8 rxerr = msg->msg.error.cc.regs.sja1000.rxerr;
+
+		/* bus error interrupt */
+		dev->can.can_stats.bus_error++;
+		stats->rx_errors++;
+
+		cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+
+		switch (ecc & SJA1000_ECC_MASK) {
+		case SJA1000_ECC_BIT:
+			cf->data[2] |= CAN_ERR_PROT_BIT;
+			break;
+		case SJA1000_ECC_FORM:
+			cf->data[2] |= CAN_ERR_PROT_FORM;
+			break;
+		case SJA1000_ECC_STUFF:
+			cf->data[2] |= CAN_ERR_PROT_STUFF;
+			break;
+		default:
+			cf->data[2] |= CAN_ERR_PROT_UNSPEC;
+			cf->data[3] = ecc & SJA1000_ECC_SEG;
+			break;
+		}
+
+		/* Error occured during transmission? */
+		if ((ecc & SJA1000_ECC_DIR) == 0)
+			cf->data[2] |= CAN_ERR_PROT_TX;
+
+		if (dev->can.state == CAN_STATE_ERROR_WARNING ||
+		    dev->can.state == CAN_STATE_ERROR_PASSIVE) {
+			cf->data[1] = (txerr > rxerr) ?
+			    CAN_ERR_CRTL_TX_PASSIVE : CAN_ERR_CRTL_RX_PASSIVE;
+		}
+	} else if (msg->type == CPC_MSG_TYPE_OVERRUN) {
+		cf->can_id |= CAN_ERR_CRTL;
+		cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
+
+		stats->rx_over_errors++;
+		stats->rx_errors++;
+	}
+
+	netif_rx(skb);
+
+	stats->rx_packets++;
+	stats->rx_bytes += cf->can_dlc;
+}
+
+/*
+ * callback for bulk IN urb
+ */
+static void ems_usb_read_bulk_callback(struct urb *urb)
+{
+	struct ems_usb *dev = urb->context;
+	struct net_device *netdev;
+	int retval;
+
+	netdev = dev->netdev;
+
+	if (!netif_device_present(netdev))
+		return;
+
+	switch (urb->status) {
+	case 0: /* success */
+		break;
+
+	case -ENOENT:
+		return;
+
+	default:
+		dev_info(netdev->dev.parent, "Rx URB aborted (%d)\n",
+			 urb->status);
+		goto resubmit_urb;
+	}
+
+	if (urb->actual_length > CPC_HEADER_SIZE) {
+		struct ems_cpc_msg *msg;
+		u8 *ibuf = urb->transfer_buffer;
+		u8 msg_count, again, start;
+
+		msg_count = ibuf[0] & ~0x80;
+		again = ibuf[0] & 0x80;
+
+		start = CPC_HEADER_SIZE;
+
+		while (msg_count) {
+			msg = (struct ems_cpc_msg *)&ibuf[start];
+
+			switch (msg->type) {
+			case CPC_MSG_TYPE_CAN_STATE:
+				/* Process CAN state changes */
+				ems_usb_rx_err(dev, msg);
+				break;
+
+			case CPC_MSG_TYPE_CAN_FRAME:
+			case CPC_MSG_TYPE_EXT_CAN_FRAME:
+			case CPC_MSG_TYPE_RTR_FRAME:
+			case CPC_MSG_TYPE_EXT_RTR_FRAME:
+				ems_usb_rx_can_msg(dev, msg);
+				break;
+
+			case CPC_MSG_TYPE_CAN_FRAME_ERROR:
+				/* Process errorframe */
+				ems_usb_rx_err(dev, msg);
+				break;
+
+			case CPC_MSG_TYPE_OVERRUN:
+				/* Message lost while receiving */
+				ems_usb_rx_err(dev, msg);
+				break;
+			}
+
+			start += CPC_MSG_HEADER_LEN + msg->length;
+			msg_count--;
+
+			if (start > urb->transfer_buffer_length) {
+				dev_err(netdev->dev.parent, "format error\n");
+				break;
+			}
+		}
+	}
+
+resubmit_urb:
+	usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2),
+			  urb->transfer_buffer, RX_BUFFER_SIZE,
+			  ems_usb_read_bulk_callback, dev);
+
+	retval = usb_submit_urb(urb, GFP_ATOMIC);
+
+	if (retval == -ENODEV)
+		netif_device_detach(netdev);
+	else if (retval)
+		dev_err(netdev->dev.parent,
+			"failed resubmitting read bulk urb: %d\n", retval);
+
+	return;
+}
+
+/*
+ * callback for bulk IN urb
+ */
+static void ems_usb_write_bulk_callback(struct urb *urb)
+{
+	struct ems_tx_urb_context *context = urb->context;
+	struct ems_usb *dev;
+	struct net_device *netdev;
+
+	BUG_ON(!context);
+
+	dev = context->dev;
+	netdev = dev->netdev;
+
+	/* free up our allocated buffer */
+	usb_buffer_free(urb->dev, urb->transfer_buffer_length,
+			urb->transfer_buffer, urb->transfer_dma);
+
+	atomic_dec(&dev->active_tx_urbs);
+
+	if (!netif_device_present(netdev))
+		return;
+
+	if (urb->status)
+		dev_info(netdev->dev.parent, "Tx URB aborted (%d)\n",
+			 urb->status);
+
+	netdev->trans_start = jiffies;
+
+	/* transmission complete interrupt */
+	netdev->stats.tx_packets++;
+	netdev->stats.tx_bytes += context->dlc;
+
+	can_get_echo_skb(netdev, context->echo_index);
+
+	/* Release context */
+	context->echo_index = MAX_TX_URBS;
+
+	if (netif_queue_stopped(netdev))
+		netif_wake_queue(netdev);
+}
+
+/*
+ * Send the given CPC command synchronously
+ */
+static int ems_usb_command_msg(struct ems_usb *dev, struct ems_cpc_msg *msg)
+{
+	int actual_length;
+
+	/* Copy payload */
+	memcpy(&dev->tx_msg_buffer[CPC_HEADER_SIZE], msg,
+	       msg->length + CPC_MSG_HEADER_LEN);
+
+	/* Clear header */
+	memset(&dev->tx_msg_buffer[0], 0, CPC_HEADER_SIZE);
+
+	return usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, 2),
+			    &dev->tx_msg_buffer[0],
+			    msg->length + CPC_MSG_HEADER_LEN + CPC_HEADER_SIZE,
+			    &actual_length, 1000);
+}
+
+/*
+ * Change CAN controllers' mode register
+ */
+static int ems_usb_write_mode(struct ems_usb *dev, u8 mode)
+{
+	dev->active_params.msg.can_params.cc_params.sja1000.mode = mode;
+
+	return ems_usb_command_msg(dev, &dev->active_params);
+}
+
+/*
+ * Send a CPC_Control command to change behaviour when interface receives a CAN
+ * message, bus error or CAN state changed notifications.
+ */
+static int ems_usb_control_cmd(struct ems_usb *dev, u8 val)
+{
+	struct ems_cpc_msg cmd;
+
+	cmd.type = CPC_CMD_TYPE_CONTROL;
+	cmd.length = CPC_MSG_HEADER_LEN + 1;
+
+	cmd.msgid = 0;
+
+	cmd.msg.generic[0] = val;
+
+	return ems_usb_command_msg(dev, &cmd);
+}
+
+/*
+ * Start interface
+ */
+static int ems_usb_start(struct ems_usb *dev)
+{
+	struct net_device *netdev = dev->netdev;
+	int err, i;
+
+	dev->intr_in_buffer[0] = 0;
+	dev->free_slots = 15; /* initial size */
+
+	for (i = 0; i < MAX_RX_URBS; i++) {
+		struct urb *urb = NULL;
+		u8 *buf = NULL;
+
+		/* create a URB, and a buffer for it */
+		urb = usb_alloc_urb(0, GFP_KERNEL);
+		if (!urb) {
+			dev_err(netdev->dev.parent,
+				"No memory left for URBs\n");
+			return -ENOMEM;
+		}
+
+		buf = usb_buffer_alloc(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
+				       &urb->transfer_dma);
+		if (!buf) {
+			dev_err(netdev->dev.parent,
+				"No memory left for USB buffer\n");
+			usb_free_urb(urb);
+			return -ENOMEM;
+		}
+
+		usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 2),
+				  buf, RX_BUFFER_SIZE,
+				  ems_usb_read_bulk_callback, dev);
+		urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+		usb_anchor_urb(urb, &dev->rx_submitted);
+
+		err = usb_submit_urb(urb, GFP_KERNEL);
+		if (err) {
+			if (err == -ENODEV)
+				netif_device_detach(dev->netdev);
+
+			usb_unanchor_urb(urb);
+			usb_buffer_free(dev->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) {
+		dev_warn(netdev->dev.parent, "couldn't setup read URBs\n");
+		return err;
+	}
+
+	/* Warn if we've couldn't transmit all the URBs */
+	if (i < MAX_RX_URBS)
+		dev_warn(netdev->dev.parent, "rx performance may be slow\n");
+
+	/* Setup and start interrupt URB */
+	usb_fill_int_urb(dev->intr_urb, dev->udev,
+			 usb_rcvintpipe(dev->udev, 1),
+			 dev->intr_in_buffer,
+			 INTR_IN_BUFFER_SIZE,
+			 ems_usb_read_interrupt_callback, dev, 1);
+
+	err = usb_submit_urb(dev->intr_urb, GFP_KERNEL);
+	if (err) {
+		if (err == -ENODEV)
+			netif_device_detach(dev->netdev);
+
+		dev_warn(netdev->dev.parent, "intr URB submit failed: %d\n",
+			 err);
+
+		return err;
+	}
+
+	/* CPC-USB will transfer received message to host */
+	err = ems_usb_control_cmd(dev, CONTR_CAN_MESSAGE | CONTR_CONT_ON);
+	if (err)
+		goto failed;
+
+	/* CPC-USB will transfer CAN state changes to host */
+	err = ems_usb_control_cmd(dev, CONTR_CAN_STATE | CONTR_CONT_ON);
+	if (err)
+		goto failed;
+
+	/* CPC-USB will transfer bus errors to host */
+	err = ems_usb_control_cmd(dev, CONTR_BUS_ERROR | CONTR_CONT_ON);
+	if (err)
+		goto failed;
+
+	err = ems_usb_write_mode(dev, SJA1000_MOD_NORMAL);
+	if (err)
+		goto failed;
+
+	dev->can.state = CAN_STATE_ERROR_ACTIVE;
+
+	return 0;
+
+failed:
+	if (err == -ENODEV)
+		netif_device_detach(dev->netdev);
+
+	dev_warn(netdev->dev.parent, "couldn't submit control: %d\n", err);
+
+	return err;
+}
+
+static void unlink_all_urbs(struct ems_usb *dev)
+{
+	int i;
+
+	usb_unlink_urb(dev->intr_urb);
+
+	usb_kill_anchored_urbs(&dev->rx_submitted);
+
+	usb_kill_anchored_urbs(&dev->tx_submitted);
+	atomic_set(&dev->active_tx_urbs, 0);
+
+	for (i = 0; i < MAX_TX_URBS; i++)
+		dev->tx_contexts[i].echo_index = MAX_TX_URBS;
+}
+
+static int ems_usb_open(struct net_device *netdev)
+{
+	struct ems_usb *dev = netdev_priv(netdev);
+	int err;
+
+	err = ems_usb_write_mode(dev, SJA1000_MOD_RM);
+	if (err)
+		return err;
+
+	/* common open */
+	err = open_candev(netdev);
+	if (err)
+		return err;
+
+	/* finally start device */
+	err = ems_usb_start(dev);
+	if (err) {
+		if (err == -ENODEV)
+			netif_device_detach(dev->netdev);
+
+		dev_warn(netdev->dev.parent, "couldn't start device: %d\n",
+			 err);
+
+		close_candev(netdev);
+
+		return err;
+	}
+
+	dev->open_time = jiffies;
+
+	netif_start_queue(netdev);
+
+	return 0;
+}
+
+static netdev_tx_t ems_usb_start_xmit(struct sk_buff *skb, struct net_device *netdev)
+{
+	struct ems_usb *dev = netdev_priv(netdev);
+	struct ems_tx_urb_context *context = NULL;
+	struct net_device_stats *stats = &netdev->stats;
+	struct can_frame *cf = (struct can_frame *)skb->data;
+	struct ems_cpc_msg *msg;
+	struct urb *urb;
+	u8 *buf;
+	int i, err;
+	size_t size = CPC_HEADER_SIZE + CPC_MSG_HEADER_LEN
+			+ sizeof(struct cpc_can_msg);
+
+	/* create a URB, and a buffer for it, and copy the data to the URB */
+	urb = usb_alloc_urb(0, GFP_ATOMIC);
+	if (!urb) {
+		dev_err(netdev->dev.parent, "No memory left for URBs\n");
+		goto nomem;
+	}
+
+	buf = usb_buffer_alloc(dev->udev, size, GFP_ATOMIC, &urb->transfer_dma);
+	if (!buf) {
+		dev_err(netdev->dev.parent, "No memory left for USB buffer\n");
+		usb_free_urb(urb);
+		goto nomem;
+	}
+
+	msg = (struct ems_cpc_msg *)&buf[CPC_HEADER_SIZE];
+
+	msg->msg.can_msg.id = cf->can_id & CAN_ERR_MASK;
+	msg->msg.can_msg.length = cf->can_dlc;
+
+	if (cf->can_id & CAN_RTR_FLAG) {
+		msg->type = cf->can_id & CAN_EFF_FLAG ?
+			CPC_CMD_TYPE_EXT_RTR_FRAME : CPC_CMD_TYPE_RTR_FRAME;
+
+		msg->length = CPC_CAN_MSG_MIN_SIZE;
+	} else {
+		msg->type = cf->can_id & CAN_EFF_FLAG ?
+			CPC_CMD_TYPE_EXT_CAN_FRAME : CPC_CMD_TYPE_CAN_FRAME;
+
+		for (i = 0; i < cf->can_dlc; i++)
+			msg->msg.can_msg.msg[i] = cf->data[i];
+
+		msg->length = CPC_CAN_MSG_MIN_SIZE + cf->can_dlc;
+	}
+
+	/* Respect byte order */
+	msg->msg.can_msg.id = cpu_to_le32(msg->msg.can_msg.id);
+
+	for (i = 0; i < MAX_TX_URBS; i++) {
+		if (dev->tx_contexts[i].echo_index == MAX_TX_URBS) {
+			context = &dev->tx_contexts[i];
+			break;
+		}
+	}
+
+	/*
+	 * May never happen! When this happens we'd more URBs in flight as
+	 * allowed (MAX_TX_URBS).
+	 */
+	if (!context) {
+		usb_unanchor_urb(urb);
+		usb_buffer_free(dev->udev, size, buf, urb->transfer_dma);
+
+		dev_warn(netdev->dev.parent, "couldn't find free context\n");
+
+		return NETDEV_TX_BUSY;
+	}
+
+	context->dev = dev;
+	context->echo_index = i;
+	context->dlc = cf->can_dlc;
+
+	usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
+			  size, ems_usb_write_bulk_callback, context);
+	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+	usb_anchor_urb(urb, &dev->tx_submitted);
+
+	can_put_echo_skb(skb, netdev, context->echo_index);
+
+	atomic_inc(&dev->active_tx_urbs);
+
+	err = usb_submit_urb(urb, GFP_ATOMIC);
+	if (unlikely(err)) {
+		can_free_echo_skb(netdev, context->echo_index);
+
+		usb_unanchor_urb(urb);
+		usb_buffer_free(dev->udev, size, buf, urb->transfer_dma);
+		dev_kfree_skb(skb);
+
+		atomic_dec(&dev->active_tx_urbs);
+
+		if (err == -ENODEV) {
+			netif_device_detach(netdev);
+		} else {
+			dev_warn(netdev->dev.parent, "failed tx_urb %d\n", err);
+
+			stats->tx_dropped++;
+		}
+	} else {
+		netdev->trans_start = jiffies;
+
+		/* Slow down tx path */
+		if (atomic_read(&dev->active_tx_urbs) >= MAX_TX_URBS ||
+		    dev->free_slots < 5) {
+			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;
+
+nomem:
+	if (skb)
+		dev_kfree_skb(skb);
+
+	stats->tx_dropped++;
+
+	return NETDEV_TX_OK;
+}
+
+static int ems_usb_close(struct net_device *netdev)
+{
+	struct ems_usb *dev = netdev_priv(netdev);
+
+	/* Stop polling */
+	unlink_all_urbs(dev);
+
+	netif_stop_queue(netdev);
+
+	/* Set CAN controller to reset mode */
+	if (ems_usb_write_mode(dev, SJA1000_MOD_RM))
+		dev_warn(netdev->dev.parent, "couldn't stop device");
+
+	close_candev(netdev);
+
+	dev->open_time = 0;
+
+	return 0;
+}
+
+static const struct net_device_ops ems_usb_netdev_ops = {
+	.ndo_open = ems_usb_open,
+	.ndo_stop = ems_usb_close,
+	.ndo_start_xmit = ems_usb_start_xmit,
+};
+
+static struct can_bittiming_const ems_usb_bittiming_const = {
+	.name = "ems_usb",
+	.tseg1_min = 1,
+	.tseg1_max = 16,
+	.tseg2_min = 1,
+	.tseg2_max = 8,
+	.sjw_max = 4,
+	.brp_min = 1,
+	.brp_max = 64,
+	.brp_inc = 1,
+};
+
+static int ems_usb_set_mode(struct net_device *netdev, enum can_mode mode)
+{
+	struct ems_usb *dev = netdev_priv(netdev);
+
+	if (!dev->open_time)
+		return -EINVAL;
+
+	switch (mode) {
+	case CAN_MODE_START:
+		if (ems_usb_write_mode(dev, SJA1000_MOD_NORMAL))
+			dev_warn(netdev->dev.parent, "couldn't start device");
+
+		if (netif_queue_stopped(netdev))
+			netif_wake_queue(netdev);
+		break;
+
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+static int ems_usb_set_bittiming(struct net_device *netdev)
+{
+	struct ems_usb *dev = netdev_priv(netdev);
+	struct can_bittiming *bt = &dev->can.bittiming;
+	u8 btr0, btr1;
+
+	btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
+	btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
+		(((bt->phase_seg2 - 1) & 0x7) << 4);
+	if (dev->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
+		btr1 |= 0x80;
+
+	dev_info(netdev->dev.parent, "setting BTR0=0x%02x BTR1=0x%02x\n",
+		 btr0, btr1);
+
+	dev->active_params.msg.can_params.cc_params.sja1000.btr0 = btr0;
+	dev->active_params.msg.can_params.cc_params.sja1000.btr1 = btr1;
+
+	return ems_usb_command_msg(dev, &dev->active_params);
+}
+
+static void init_params_sja1000(struct ems_cpc_msg *msg)
+{
+	struct cpc_sja1000_params *sja1000 =
+		&msg->msg.can_params.cc_params.sja1000;
+
+	msg->type = CPC_CMD_TYPE_CAN_PARAMS;
+	msg->length = sizeof(struct cpc_can_params);
+	msg->msgid = 0;
+
+	msg->msg.can_params.cc_type = CPC_CC_TYPE_SJA1000;
+
+	/* Acceptance filter open */
+	sja1000->acc_code0 = 0x00;
+	sja1000->acc_code1 = 0x00;
+	sja1000->acc_code2 = 0x00;
+	sja1000->acc_code3 = 0x00;
+
+	/* Acceptance filter open */
+	sja1000->acc_mask0 = 0xFF;
+	sja1000->acc_mask1 = 0xFF;
+	sja1000->acc_mask2 = 0xFF;
+	sja1000->acc_mask3 = 0xFF;
+
+	sja1000->btr0 = 0;
+	sja1000->btr1 = 0;
+
+	sja1000->outp_contr = SJA1000_DEFAULT_OUTPUT_CONTROL;
+	sja1000->mode = SJA1000_MOD_RM;
+}
+
+/*
+ * probe function for new CPC-USB devices
+ */
+static int ems_usb_probe(struct usb_interface *intf,
+			 const struct usb_device_id *id)
+{
+	struct net_device *netdev;
+	struct ems_usb *dev;
+	int i, err = -ENOMEM;
+
+	netdev = alloc_candev(sizeof(struct ems_usb));
+	if (!netdev) {
+		dev_err(netdev->dev.parent, "Couldn't alloc candev\n");
+		return -ENOMEM;
+	}
+
+	dev = netdev_priv(netdev);
+
+	dev->udev = interface_to_usbdev(intf);
+	dev->netdev = netdev;
+
+	dev->can.state = CAN_STATE_STOPPED;
+	dev->can.clock.freq = EMS_USB_ARM7_CLOCK;
+	dev->can.bittiming_const = &ems_usb_bittiming_const;
+	dev->can.do_set_bittiming = ems_usb_set_bittiming;
+	dev->can.do_set_mode = ems_usb_set_mode;
+
+	netdev->flags |= IFF_ECHO; /* we support local echo */
+
+	netdev->netdev_ops = &ems_usb_netdev_ops;
+
+	netdev->flags |= IFF_ECHO; /* we support local echo */
+
+	init_usb_anchor(&dev->rx_submitted);
+
+	init_usb_anchor(&dev->tx_submitted);
+	atomic_set(&dev->active_tx_urbs, 0);
+
+	for (i = 0; i < MAX_TX_URBS; i++)
+		dev->tx_contexts[i].echo_index = MAX_TX_URBS;
+
+	dev->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!dev->intr_urb) {
+		dev_err(netdev->dev.parent, "Couldn't alloc intr URB\n");
+		goto cleanup_candev;
+	}
+
+	dev->intr_in_buffer = kzalloc(INTR_IN_BUFFER_SIZE, GFP_KERNEL);
+	if (!dev->intr_in_buffer) {
+		dev_err(netdev->dev.parent, "Couldn't alloc Intr buffer\n");
+		goto cleanup_intr_urb;
+	}
+
+	dev->tx_msg_buffer = kzalloc(CPC_HEADER_SIZE +
+				     sizeof(struct ems_cpc_msg), GFP_KERNEL);
+	if (!dev->tx_msg_buffer) {
+		dev_err(netdev->dev.parent, "Couldn't alloc Tx buffer\n");
+		goto cleanup_intr_in_buffer;
+	}
+
+	usb_set_intfdata(intf, dev);
+
+	SET_NETDEV_DEV(netdev, &intf->dev);
+
+	init_params_sja1000(&dev->active_params);
+
+	err = ems_usb_command_msg(dev, &dev->active_params);
+	if (err) {
+		dev_err(netdev->dev.parent,
+			"couldn't initialize controller: %d\n", err);
+		goto cleanup_tx_msg_buffer;
+	}
+
+	err = register_candev(netdev);
+	if (err) {
+		dev_err(netdev->dev.parent,
+			"couldn't register CAN device: %d\n", err);
+		goto cleanup_tx_msg_buffer;
+	}
+
+	return 0;
+
+cleanup_tx_msg_buffer:
+	kfree(dev->tx_msg_buffer);
+
+cleanup_intr_in_buffer:
+	kfree(dev->intr_in_buffer);
+
+cleanup_intr_urb:
+	usb_free_urb(dev->intr_urb);
+
+cleanup_candev:
+	free_candev(netdev);
+
+	return err;
+}
+
+/*
+ * called by the usb core when the device is removed from the system
+ */
+static void ems_usb_disconnect(struct usb_interface *intf)
+{
+	struct ems_usb *dev = usb_get_intfdata(intf);
+
+	usb_set_intfdata(intf, NULL);
+
+	if (dev) {
+		unregister_netdev(dev->netdev);
+		free_candev(dev->netdev);
+
+		unlink_all_urbs(dev);
+
+		usb_free_urb(dev->intr_urb);
+
+		kfree(dev->intr_in_buffer);
+	}
+}
+
+/* usb specific object needed to register this driver with the usb subsystem */
+static struct usb_driver ems_usb_driver = {
+	.name = "ems_usb",
+	.probe = ems_usb_probe,
+	.disconnect = ems_usb_disconnect,
+	.id_table = ems_usb_table,
+};
+
+static int __init ems_usb_init(void)
+{
+	int err;
+
+	printk(KERN_INFO "CPC-USB kernel driver loaded\n");
+
+	/* register this driver with the USB subsystem */
+	err = usb_register(&ems_usb_driver);
+
+	if (err) {
+		err("usb_register failed. Error number %d\n", err);
+		return err;
+	}
+
+	return 0;
+}
+
+static void __exit ems_usb_exit(void)
+{
+	/* deregister this driver with the USB subsystem */
+	usb_deregister(&ems_usb_driver);
+}
+
+module_init(ems_usb_init);
+module_exit(ems_usb_exit);