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-rw-r--r--drivers/net/can/at91_can.c1438
1 files changed, 1438 insertions, 0 deletions
diff --git a/drivers/net/can/at91_can.c b/drivers/net/can/at91_can.c
new file mode 100644
index 000000000..f4e40aa4d
--- /dev/null
+++ b/drivers/net/can/at91_can.c
@@ -0,0 +1,1438 @@
+/*
+ * at91_can.c - CAN network driver for AT91 SoC CAN controller
+ *
+ * (C) 2007 by Hans J. Koch <hjk@hansjkoch.de>
+ * (C) 2008, 2009, 2010, 2011 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.
+ *
+ *
+ * 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/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/rtnetlink.h>
+#include <linux/skbuff.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/platform_data/atmel.h>
+
+#include <linux/can/dev.h>
+#include <linux/can/error.h>
+#include <linux/can/led.h>
+
+#define AT91_MB_MASK(i) ((1 << (i)) - 1)
+
+/* 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_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)
+
+enum at91_devtype {
+ AT91_DEVTYPE_SAM9263,
+ AT91_DEVTYPE_SAM9X5,
+};
+
+struct at91_devtype_data {
+ unsigned int rx_first;
+ unsigned int rx_split;
+ unsigned int rx_last;
+ unsigned int tx_shift;
+ enum at91_devtype type;
+};
+
+struct at91_priv {
+ struct can_priv can; /* must be the first member! */
+ struct napi_struct napi;
+
+ void __iomem *reg_base;
+
+ u32 reg_sr;
+ unsigned int tx_next;
+ unsigned int tx_echo;
+ unsigned int rx_next;
+ struct at91_devtype_data devtype_data;
+
+ struct clk *clk;
+ struct at91_can_data *pdata;
+
+ canid_t mb0_id;
+};
+
+static const struct at91_devtype_data at91_at91sam9263_data = {
+ .rx_first = 1,
+ .rx_split = 8,
+ .rx_last = 11,
+ .tx_shift = 2,
+ .type = AT91_DEVTYPE_SAM9263,
+};
+
+static const struct at91_devtype_data at91_at91sam9x5_data = {
+ .rx_first = 0,
+ .rx_split = 4,
+ .rx_last = 5,
+ .tx_shift = 1,
+ .type = AT91_DEVTYPE_SAM9X5,
+};
+
+static const struct can_bittiming_const at91_bittiming_const = {
+ .name = KBUILD_MODNAME,
+ .tseg1_min = 4,
+ .tseg1_max = 16,
+ .tseg2_min = 2,
+ .tseg2_max = 8,
+ .sjw_max = 4,
+ .brp_min = 2,
+ .brp_max = 128,
+ .brp_inc = 1,
+};
+
+#define AT91_IS(_model) \
+static inline int at91_is_sam##_model(const struct at91_priv *priv) \
+{ \
+ return priv->devtype_data.type == AT91_DEVTYPE_SAM##_model; \
+}
+
+AT91_IS(9263);
+AT91_IS(9X5);
+
+static inline unsigned int get_mb_rx_first(const struct at91_priv *priv)
+{
+ return priv->devtype_data.rx_first;
+}
+
+static inline unsigned int get_mb_rx_last(const struct at91_priv *priv)
+{
+ return priv->devtype_data.rx_last;
+}
+
+static inline unsigned int get_mb_rx_split(const struct at91_priv *priv)
+{
+ return priv->devtype_data.rx_split;
+}
+
+static inline unsigned int get_mb_rx_num(const struct at91_priv *priv)
+{
+ return get_mb_rx_last(priv) - get_mb_rx_first(priv) + 1;
+}
+
+static inline unsigned int get_mb_rx_low_last(const struct at91_priv *priv)
+{
+ return get_mb_rx_split(priv) - 1;
+}
+
+static inline unsigned int get_mb_rx_low_mask(const struct at91_priv *priv)
+{
+ return AT91_MB_MASK(get_mb_rx_split(priv)) &
+ ~AT91_MB_MASK(get_mb_rx_first(priv));
+}
+
+static inline unsigned int get_mb_tx_shift(const struct at91_priv *priv)
+{
+ return priv->devtype_data.tx_shift;
+}
+
+static inline unsigned int get_mb_tx_num(const struct at91_priv *priv)
+{
+ return 1 << get_mb_tx_shift(priv);
+}
+
+static inline unsigned int get_mb_tx_first(const struct at91_priv *priv)
+{
+ return get_mb_rx_last(priv) + 1;
+}
+
+static inline unsigned int get_mb_tx_last(const struct at91_priv *priv)
+{
+ return get_mb_tx_first(priv) + get_mb_tx_num(priv) - 1;
+}
+
+static inline unsigned int get_next_prio_shift(const struct at91_priv *priv)
+{
+ return get_mb_tx_shift(priv);
+}
+
+static inline unsigned int get_next_prio_mask(const struct at91_priv *priv)
+{
+ return 0xf << get_mb_tx_shift(priv);
+}
+
+static inline unsigned int get_next_mb_mask(const struct at91_priv *priv)
+{
+ return AT91_MB_MASK(get_mb_tx_shift(priv));
+}
+
+static inline unsigned int get_next_mask(const struct at91_priv *priv)
+{
+ return get_next_mb_mask(priv) | get_next_prio_mask(priv);
+}
+
+static inline unsigned int get_irq_mb_rx(const struct at91_priv *priv)
+{
+ return AT91_MB_MASK(get_mb_rx_last(priv) + 1) &
+ ~AT91_MB_MASK(get_mb_rx_first(priv));
+}
+
+static inline unsigned int get_irq_mb_tx(const struct at91_priv *priv)
+{
+ return AT91_MB_MASK(get_mb_tx_last(priv) + 1) &
+ ~AT91_MB_MASK(get_mb_tx_first(priv));
+}
+
+static inline unsigned int get_tx_next_mb(const struct at91_priv *priv)
+{
+ return (priv->tx_next & get_next_mb_mask(priv)) + get_mb_tx_first(priv);
+}
+
+static inline unsigned int get_tx_next_prio(const struct at91_priv *priv)
+{
+ return (priv->tx_next >> get_next_prio_shift(priv)) & 0xf;
+}
+
+static inline unsigned int get_tx_echo_mb(const struct at91_priv *priv)
+{
+ return (priv->tx_echo & get_next_mb_mask(priv)) + get_mb_tx_first(priv);
+}
+
+static inline u32 at91_read(const struct at91_priv *priv, enum at91_reg reg)
+{
+ return readl_relaxed(priv->reg_base + reg);
+}
+
+static inline void at91_write(const struct at91_priv *priv, enum at91_reg reg,
+ u32 value)
+{
+ writel_relaxed(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 inline u32 at91_can_id_to_reg_mid(canid_t can_id)
+{
+ u32 reg_mid;
+
+ if (can_id & CAN_EFF_FLAG)
+ reg_mid = (can_id & CAN_EFF_MASK) | AT91_MID_MIDE;
+ else
+ reg_mid = (can_id & CAN_SFF_MASK) << 18;
+
+ return reg_mid;
+}
+
+/*
+ * 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;
+ u32 reg_mid;
+
+ /*
+ * Due to a chip bug (errata 50.2.6.3 & 50.3.5.3) the first
+ * mailbox is disabled. The next 11 mailboxes are used as a
+ * reception FIFO. The last mailbox is configured with
+ * overwrite option. The overwrite flag indicates a FIFO
+ * overflow.
+ */
+ reg_mid = at91_can_id_to_reg_mid(priv->mb0_id);
+ for (i = 0; i < get_mb_rx_first(priv); i++) {
+ set_mb_mode(priv, i, AT91_MB_MODE_DISABLED);
+ at91_write(priv, AT91_MID(i), reg_mid);
+ at91_write(priv, AT91_MCR(i), 0x0); /* clear dlc */
+ }
+
+ for (i = get_mb_rx_first(priv); i < get_mb_rx_last(priv); i++)
+ set_mb_mode(priv, i, AT91_MB_MODE_RX);
+ set_mb_mode(priv, get_mb_rx_last(priv), AT91_MB_MODE_RX_OVRWR);
+
+ /* reset acceptance mask and id register */
+ for (i = get_mb_rx_first(priv); i <= get_mb_rx_last(priv); i++) {
+ at91_write(priv, AT91_MAM(i), 0x0);
+ at91_write(priv, AT91_MID(i), AT91_MID_MIDE);
+ }
+
+ /* The last 4 mailboxes are used for transmitting. */
+ for (i = get_mb_tx_first(priv); i <= get_mb_tx_last(priv); i++)
+ set_mb_mode_prio(priv, i, AT91_MB_MODE_TX, 0);
+
+ /* Reset tx and rx helper pointers */
+ priv->tx_next = priv->tx_echo = 0;
+ priv->rx_next = get_mb_rx_first(priv);
+}
+
+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) ? 1 << 24 : 0) |
+ ((bt->brp - 1) << 16) | ((bt->sjw - 1) << 12) |
+ ((bt->prop_seg - 1) << 8) | ((bt->phase_seg1 - 1) << 4) |
+ ((bt->phase_seg2 - 1) << 0);
+
+ netdev_info(dev, "writing AT91_BR: 0x%08x\n", reg_br);
+
+ at91_write(priv, AT91_BR, reg_br);
+
+ return 0;
+}
+
+static int at91_get_berr_counter(const struct net_device *dev,
+ struct can_berr_counter *bec)
+{
+ const struct at91_priv *priv = netdev_priv(dev);
+ u32 reg_ecr = at91_read(priv, AT91_ECR);
+
+ bec->rxerr = reg_ecr & 0xff;
+ bec->txerr = reg_ecr >> 16;
+
+ 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_set_bittiming(dev);
+ at91_setup_mailboxes(dev);
+ at91_transceiver_switch(priv, 1);
+
+ /* enable chip */
+ if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
+ reg_mr = AT91_MR_CANEN | AT91_MR_ABM;
+ else
+ reg_mr = AT91_MR_CANEN;
+ at91_write(priv, AT91_MR, reg_mr);
+
+ priv->can.state = CAN_STATE_ERROR_ACTIVE;
+
+ /* Enable interrupts */
+ reg_ier = get_irq_mb_rx(priv) | 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 << get_next_prio_shift(priv)) |
+ * (mb - get_mb_tx_first(priv));
+ *
+ */
+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;
+
+ if (can_dropped_invalid_skb(dev, skb))
+ return NETDEV_TX_OK;
+
+ 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);
+
+ netdev_err(dev, "BUG! TX buffer full when queue awake!\n");
+ return NETDEV_TX_BUSY;
+ }
+ reg_mid = at91_can_id_to_reg_mid(cf->can_id);
+ 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;
+
+ /* _NOTE_: subtract AT91_MB_TX_FIRST offset from mb! */
+ can_put_echo_skb(skb, dev, mb - get_mb_tx_first(priv));
+
+ /*
+ * 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 & get_next_mask(priv)) == 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 = get_mb_rx_low_mask(priv);
+ 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;
+
+ netdev_dbg(dev, "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));
+ cf->can_dlc = get_can_dlc((reg_msr >> 16) & 0xf);
+
+ if (reg_msr & AT91_MSR_MRTR)
+ cf->can_id |= CAN_RTR_FLAG;
+ else {
+ *(u32 *)(cf->data + 0) = at91_read(priv, AT91_MDL(mb));
+ *(u32 *)(cf->data + 4) = at91_read(priv, AT91_MDH(mb));
+ }
+
+ /* allow RX of extended frames */
+ at91_write(priv, AT91_MID(mb), AT91_MID_MIDE);
+
+ if (unlikely(mb == get_mb_rx_last(priv) && 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;
+
+ can_led_event(dev, CAN_LED_EVENT_RX);
+}
+
+/**
+ * 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:
+ *
+ * About 3/4 of the mailboxes (get_mb_rx_first()...get_mb_rx_last())
+ * on the chip are reserved for RX. We split them into 2 groups. The
+ * lower group ranges from get_mb_rx_first() to get_mb_rx_low_last().
+ *
+ * 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. 1 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|| | | | |
+ * +-+-+-+-+-+-+-+-++-+-+-+-+
+ * 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
+ * ^
+ * |
+ * \
+ * unused, due to chip bug
+ *
+ * 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 > get_mb_rx_low_last(priv) &&
+ reg_sr & get_mb_rx_low_mask(priv))
+ netdev_info(dev,
+ "order of incoming frames cannot be guaranteed\n");
+
+ again:
+ for (mb = find_next_bit(addr, get_mb_tx_first(priv), priv->rx_next);
+ mb < get_mb_tx_first(priv) && quota > 0;
+ reg_sr = at91_read(priv, AT91_SR),
+ mb = find_next_bit(addr, get_mb_tx_first(priv), ++priv->rx_next)) {
+ at91_read_msg(dev, mb);
+
+ /* reactivate mailboxes */
+ if (mb == get_mb_rx_low_last(priv))
+ /* all lower mailboxed, if just finished it */
+ at91_activate_rx_low(priv);
+ else if (mb > get_mb_rx_low_last(priv))
+ /* only the mailbox we read */
+ at91_activate_rx_mb(priv, mb);
+
+ received++;
+ quota--;
+ }
+
+ /* upper group completed, look again in lower */
+ if (priv->rx_next > get_mb_rx_low_last(priv) &&
+ quota > 0 && mb > get_mb_rx_last(priv)) {
+ priv->rx_next = get_mb_rx_first(priv);
+ 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) {
+ netdev_dbg(dev, "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) {
+ netdev_dbg(dev, "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) {
+ netdev_dbg(dev, "AERR irq\n");
+ dev->stats.tx_errors++;
+ cf->can_id |= CAN_ERR_ACK;
+ }
+
+ /* Form error */
+ if (reg_sr & AT91_IRQ_FERR) {
+ netdev_dbg(dev, "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) {
+ netdev_dbg(dev, "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->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 & get_irq_mb_rx(priv))
+ 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 |= get_irq_mb_rx(priv) & ~AT91_MB_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_: 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);
+ }
+ }
+
+ /*
+ * 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 & get_next_mask(priv)) != 0 ||
+ (priv->tx_echo & get_next_mask(priv)) == 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 = 0, reg_ier = 0;
+ struct can_berr_counter bec;
+
+ at91_get_berr_counter(dev, &bec);
+
+ 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) {
+ netdev_dbg(dev, "Error Warning IRQ\n");
+ priv->can.can_stats.error_warning++;
+
+ cf->can_id |= CAN_ERR_CRTL;
+ cf->data[1] = (bec.txerr > bec.rxerr) ?
+ 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) {
+ netdev_dbg(dev, "Error Passive IRQ\n");
+ priv->can.can_stats.error_passive++;
+
+ cf->can_id |= CAN_ERR_CRTL;
+ cf->data[1] = (bec.txerr > bec.rxerr) ?
+ 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;
+
+ netdev_dbg(dev, "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"
+ */
+ netdev_dbg(dev, "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;
+
+ netdev_dbg(dev, "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 int at91_get_state_by_bec(const struct net_device *dev,
+ enum can_state *state)
+{
+ struct can_berr_counter bec;
+ int err;
+
+ err = at91_get_berr_counter(dev, &bec);
+ if (err)
+ return err;
+
+ if (bec.txerr < 96 && bec.rxerr < 96)
+ *state = CAN_STATE_ERROR_ACTIVE;
+ else if (bec.txerr < 128 && bec.rxerr < 128)
+ *state = CAN_STATE_ERROR_WARNING;
+ else if (bec.txerr < 256 && bec.rxerr < 256)
+ *state = CAN_STATE_ERROR_PASSIVE;
+ else
+ *state = CAN_STATE_BUS_OFF;
+
+ return 0;
+}
+
+
+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;
+ int err;
+
+ if (at91_is_sam9263(priv)) {
+ 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 {
+ netdev_err(dev, "BUG! hardware in undefined state\n");
+ return;
+ }
+ } else {
+ err = at91_get_state_by_bec(dev, &new_state);
+ if (err)
+ 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->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 & (get_irq_mb_rx(priv) | 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,
+ get_irq_mb_rx(priv) | AT91_IRQ_ERR_FRAME);
+ napi_schedule(&priv->napi);
+ }
+
+ /* Transmission complete interrupt */
+ if (reg_sr & get_irq_mb_tx(priv))
+ 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;
+
+ err = clk_prepare_enable(priv->clk);
+ if (err)
+ return err;
+
+ /* 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;
+ }
+
+ can_led_event(dev, CAN_LED_EVENT_OPEN);
+
+ /* 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_unprepare(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_unprepare(priv->clk);
+
+ close_candev(dev);
+
+ can_led_event(dev, CAN_LED_EVENT_STOP);
+
+ 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,
+ .ndo_change_mtu = can_change_mtu,
+};
+
+static ssize_t at91_sysfs_show_mb0_id(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct at91_priv *priv = netdev_priv(to_net_dev(dev));
+
+ if (priv->mb0_id & CAN_EFF_FLAG)
+ return snprintf(buf, PAGE_SIZE, "0x%08x\n", priv->mb0_id);
+ else
+ return snprintf(buf, PAGE_SIZE, "0x%03x\n", priv->mb0_id);
+}
+
+static ssize_t at91_sysfs_set_mb0_id(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct net_device *ndev = to_net_dev(dev);
+ struct at91_priv *priv = netdev_priv(ndev);
+ unsigned long can_id;
+ ssize_t ret;
+ int err;
+
+ rtnl_lock();
+
+ if (ndev->flags & IFF_UP) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ err = kstrtoul(buf, 0, &can_id);
+ if (err) {
+ ret = err;
+ goto out;
+ }
+
+ if (can_id & CAN_EFF_FLAG)
+ can_id &= CAN_EFF_MASK | CAN_EFF_FLAG;
+ else
+ can_id &= CAN_SFF_MASK;
+
+ priv->mb0_id = can_id;
+ ret = count;
+
+ out:
+ rtnl_unlock();
+ return ret;
+}
+
+static DEVICE_ATTR(mb0_id, S_IWUSR | S_IRUGO,
+ at91_sysfs_show_mb0_id, at91_sysfs_set_mb0_id);
+
+static struct attribute *at91_sysfs_attrs[] = {
+ &dev_attr_mb0_id.attr,
+ NULL,
+};
+
+static struct attribute_group at91_sysfs_attr_group = {
+ .attrs = at91_sysfs_attrs,
+};
+
+#if defined(CONFIG_OF)
+static const struct of_device_id at91_can_dt_ids[] = {
+ {
+ .compatible = "atmel,at91sam9x5-can",
+ .data = &at91_at91sam9x5_data,
+ }, {
+ .compatible = "atmel,at91sam9263-can",
+ .data = &at91_at91sam9263_data,
+ }, {
+ /* sentinel */
+ }
+};
+MODULE_DEVICE_TABLE(of, at91_can_dt_ids);
+#endif
+
+static const struct at91_devtype_data *at91_can_get_driver_data(struct platform_device *pdev)
+{
+ if (pdev->dev.of_node) {
+ const struct of_device_id *match;
+
+ match = of_match_node(at91_can_dt_ids, pdev->dev.of_node);
+ if (!match) {
+ dev_err(&pdev->dev, "no matching node found in dtb\n");
+ return NULL;
+ }
+ return (const struct at91_devtype_data *)match->data;
+ }
+ return (const struct at91_devtype_data *)
+ platform_get_device_id(pdev)->driver_data;
+}
+
+static int at91_can_probe(struct platform_device *pdev)
+{
+ const struct at91_devtype_data *devtype_data;
+ struct net_device *dev;
+ struct at91_priv *priv;
+ struct resource *res;
+ struct clk *clk;
+ void __iomem *addr;
+ int err, irq;
+
+ devtype_data = at91_can_get_driver_data(pdev);
+ if (!devtype_data) {
+ dev_err(&pdev->dev, "no driver data\n");
+ err = -ENODEV;
+ goto exit;
+ }
+
+ 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 <= 0) {
+ 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),
+ 1 << devtype_data->tx_shift);
+ 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_mode = at91_set_mode;
+ priv->can.do_get_berr_counter = at91_get_berr_counter;
+ priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES |
+ CAN_CTRLMODE_LISTENONLY;
+ priv->reg_base = addr;
+ priv->devtype_data = *devtype_data;
+ priv->clk = clk;
+ priv->pdata = dev_get_platdata(&pdev->dev);
+ priv->mb0_id = 0x7ff;
+
+ netif_napi_add(dev, &priv->napi, at91_poll, get_mb_rx_num(priv));
+
+ if (at91_is_sam9263(priv))
+ dev->sysfs_groups[0] = &at91_sysfs_attr_group;
+
+ platform_set_drvdata(pdev, dev);
+ SET_NETDEV_DEV(dev, &pdev->dev);
+
+ err = register_candev(dev);
+ if (err) {
+ dev_err(&pdev->dev, "registering netdev failed\n");
+ 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);
+
+ return 0;
+
+ exit_free:
+ free_candev(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 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);
+
+ iounmap(priv->reg_base);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ release_mem_region(res->start, resource_size(res));
+
+ clk_put(priv->clk);
+
+ free_candev(dev);
+
+ return 0;
+}
+
+static const struct platform_device_id at91_can_id_table[] = {
+ {
+ .name = "at91sam9x5_can",
+ .driver_data = (kernel_ulong_t)&at91_at91sam9x5_data,
+ }, {
+ .name = "at91_can",
+ .driver_data = (kernel_ulong_t)&at91_at91sam9263_data,
+ }, {
+ /* sentinel */
+ }
+};
+MODULE_DEVICE_TABLE(platform, at91_can_id_table);
+
+static struct platform_driver at91_can_driver = {
+ .probe = at91_can_probe,
+ .remove = at91_can_remove,
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .of_match_table = of_match_ptr(at91_can_dt_ids),
+ },
+ .id_table = at91_can_id_table,
+};
+
+module_platform_driver(at91_can_driver);
+
+MODULE_AUTHOR("Marc Kleine-Budde <mkl@pengutronix.de>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION(KBUILD_MODNAME " CAN netdevice driver");