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path: root/drivers/net/can/mscan/mscan.c
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Diffstat (limited to 'drivers/net/can/mscan/mscan.c')
-rw-r--r--drivers/net/can/mscan/mscan.c699
1 files changed, 699 insertions, 0 deletions
diff --git a/drivers/net/can/mscan/mscan.c b/drivers/net/can/mscan/mscan.c
new file mode 100644
index 00000000000..49542cab9df
--- /dev/null
+++ b/drivers/net/can/mscan/mscan.c
@@ -0,0 +1,699 @@
+/*
+ * CAN bus driver for the alone generic (as possible as) MSCAN controller.
+ *
+ * Copyright (C) 2005-2006 Andrey Volkov <avolkov@varma-el.com>,
+ * Varma Electronics Oy
+ * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
+ * Copytight (C) 2008-2009 Pengutronix <kernel@pengutronix.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the version 2 of the GNU General Public License
+ * as published by the Free Software Foundation
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/if_ether.h>
+#include <linux/list.h>
+#include <linux/can.h>
+#include <linux/can/dev.h>
+#include <linux/can/error.h>
+#include <linux/io.h>
+
+#include "mscan.h"
+
+#define MSCAN_NORMAL_MODE 0
+#define MSCAN_SLEEP_MODE MSCAN_SLPRQ
+#define MSCAN_INIT_MODE (MSCAN_INITRQ | MSCAN_SLPRQ)
+#define MSCAN_POWEROFF_MODE (MSCAN_CSWAI | MSCAN_SLPRQ)
+#define MSCAN_SET_MODE_RETRIES 255
+#define MSCAN_ECHO_SKB_MAX 3
+
+#define BTR0_BRP_MASK 0x3f
+#define BTR0_SJW_SHIFT 6
+#define BTR0_SJW_MASK (0x3 << BTR0_SJW_SHIFT)
+
+#define BTR1_TSEG1_MASK 0xf
+#define BTR1_TSEG2_SHIFT 4
+#define BTR1_TSEG2_MASK (0x7 << BTR1_TSEG2_SHIFT)
+#define BTR1_SAM_SHIFT 7
+
+#define BTR0_SET_BRP(brp) (((brp) - 1) & BTR0_BRP_MASK)
+#define BTR0_SET_SJW(sjw) ((((sjw) - 1) << BTR0_SJW_SHIFT) & \
+ BTR0_SJW_MASK)
+
+#define BTR1_SET_TSEG1(tseg1) (((tseg1) - 1) & BTR1_TSEG1_MASK)
+#define BTR1_SET_TSEG2(tseg2) ((((tseg2) - 1) << BTR1_TSEG2_SHIFT) & \
+ BTR1_TSEG2_MASK)
+#define BTR1_SET_SAM(sam) ((sam) ? 1 << BTR1_SAM_SHIFT : 0)
+
+static struct can_bittiming_const mscan_bittiming_const = {
+ .name = "mscan",
+ .tseg1_min = 4,
+ .tseg1_max = 16,
+ .tseg2_min = 2,
+ .tseg2_max = 8,
+ .sjw_max = 4,
+ .brp_min = 1,
+ .brp_max = 64,
+ .brp_inc = 1,
+};
+
+struct mscan_state {
+ u8 mode;
+ u8 canrier;
+ u8 cantier;
+};
+
+#define F_RX_PROGRESS 0
+#define F_TX_PROGRESS 1
+#define F_TX_WAIT_ALL 2
+
+static enum can_state state_map[] = {
+ CAN_STATE_ERROR_ACTIVE,
+ CAN_STATE_ERROR_WARNING,
+ CAN_STATE_ERROR_PASSIVE,
+ CAN_STATE_BUS_OFF
+};
+
+static int mscan_set_mode(struct net_device *dev, u8 mode)
+{
+ struct mscan_priv *priv = netdev_priv(dev);
+ struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
+ int ret = 0;
+ int i;
+ u8 canctl1;
+
+ if (mode != MSCAN_NORMAL_MODE) {
+
+ if (priv->tx_active) {
+ /* Abort transfers before going to sleep */#
+ out_8(&regs->cantarq, priv->tx_active);
+ /* Suppress TX done interrupts */
+ out_8(&regs->cantier, 0);
+ }
+
+ canctl1 = in_8(&regs->canctl1);
+ if ((mode & MSCAN_SLPRQ) && (canctl1 & MSCAN_SLPAK) == 0) {
+ out_8(&regs->canctl0,
+ in_8(&regs->canctl0) | MSCAN_SLPRQ);
+ for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) {
+ if (in_8(&regs->canctl1) & MSCAN_SLPAK)
+ break;
+ udelay(100);
+ }
+ /*
+ * The mscan controller will fail to enter sleep mode,
+ * while there are irregular activities on bus, like
+ * somebody keeps retransmitting. This behavior is
+ * undocumented and seems to differ between mscan built
+ * in mpc5200b and mpc5200. We proceed in that case,
+ * since otherwise the slprq will be kept set and the
+ * controller will get stuck. NOTE: INITRQ or CSWAI
+ * will abort all active transmit actions, if still
+ * any, at once.
+ */
+ if (i >= MSCAN_SET_MODE_RETRIES)
+ dev_dbg(dev->dev.parent,
+ "device failed to enter sleep mode. "
+ "We proceed anyhow.\n");
+ else
+ priv->can.state = CAN_STATE_SLEEPING;
+ }
+
+ if ((mode & MSCAN_INITRQ) && (canctl1 & MSCAN_INITAK) == 0) {
+ out_8(&regs->canctl0,
+ in_8(&regs->canctl0) | MSCAN_INITRQ);
+ for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) {
+ if (in_8(&regs->canctl1) & MSCAN_INITAK)
+ break;
+ }
+ if (i >= MSCAN_SET_MODE_RETRIES)
+ ret = -ENODEV;
+ }
+ if (!ret)
+ priv->can.state = CAN_STATE_STOPPED;
+
+ if (mode & MSCAN_CSWAI)
+ out_8(&regs->canctl0,
+ in_8(&regs->canctl0) | MSCAN_CSWAI);
+
+ } else {
+ canctl1 = in_8(&regs->canctl1);
+ if (canctl1 & (MSCAN_SLPAK | MSCAN_INITAK)) {
+ out_8(&regs->canctl0, in_8(&regs->canctl0) &
+ ~(MSCAN_SLPRQ | MSCAN_INITRQ));
+ for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) {
+ canctl1 = in_8(&regs->canctl1);
+ if (!(canctl1 & (MSCAN_INITAK | MSCAN_SLPAK)))
+ break;
+ }
+ if (i >= MSCAN_SET_MODE_RETRIES)
+ ret = -ENODEV;
+ else
+ priv->can.state = CAN_STATE_ERROR_ACTIVE;
+ }
+ }
+ return ret;
+}
+
+static int mscan_start(struct net_device *dev)
+{
+ struct mscan_priv *priv = netdev_priv(dev);
+ struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
+ u8 canrflg;
+ int err;
+
+ out_8(&regs->canrier, 0);
+
+ INIT_LIST_HEAD(&priv->tx_head);
+ priv->prev_buf_id = 0;
+ priv->cur_pri = 0;
+ priv->tx_active = 0;
+ priv->shadow_canrier = 0;
+ priv->flags = 0;
+
+ err = mscan_set_mode(dev, MSCAN_NORMAL_MODE);
+ if (err)
+ return err;
+
+ canrflg = in_8(&regs->canrflg);
+ priv->shadow_statflg = canrflg & MSCAN_STAT_MSK;
+ priv->can.state = state_map[max(MSCAN_STATE_RX(canrflg),
+ MSCAN_STATE_TX(canrflg))];
+ out_8(&regs->cantier, 0);
+
+ /* Enable receive interrupts. */
+ out_8(&regs->canrier, MSCAN_OVRIE | MSCAN_RXFIE | MSCAN_CSCIE |
+ MSCAN_RSTATE1 | MSCAN_RSTATE0 | MSCAN_TSTATE1 | MSCAN_TSTATE0);
+
+ return 0;
+}
+
+static netdev_tx_t mscan_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct can_frame *frame = (struct can_frame *)skb->data;
+ struct mscan_priv *priv = netdev_priv(dev);
+ struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
+ int i, rtr, buf_id;
+ u32 can_id;
+
+ if (frame->can_dlc > 8)
+ return -EINVAL;
+
+ out_8(&regs->cantier, 0);
+
+ i = ~priv->tx_active & MSCAN_TXE;
+ buf_id = ffs(i) - 1;
+ switch (hweight8(i)) {
+ case 0:
+ netif_stop_queue(dev);
+ dev_err(dev->dev.parent, "Tx Ring full when queue awake!\n");
+ return NETDEV_TX_BUSY;
+ case 1:
+ /*
+ * if buf_id < 3, then current frame will be send out of order,
+ * since buffer with lower id have higher priority (hell..)
+ */
+ netif_stop_queue(dev);
+ case 2:
+ if (buf_id < priv->prev_buf_id) {
+ priv->cur_pri++;
+ if (priv->cur_pri == 0xff) {
+ set_bit(F_TX_WAIT_ALL, &priv->flags);
+ netif_stop_queue(dev);
+ }
+ }
+ set_bit(F_TX_PROGRESS, &priv->flags);
+ break;
+ }
+ priv->prev_buf_id = buf_id;
+ out_8(&regs->cantbsel, i);
+
+ rtr = frame->can_id & CAN_RTR_FLAG;
+
+ if (frame->can_id & CAN_EFF_FLAG) {
+ can_id = (frame->can_id & CAN_EFF_MASK) << 1;
+ if (rtr)
+ can_id |= 1;
+ out_be16(&regs->tx.idr3_2, can_id);
+
+ can_id >>= 16;
+ can_id = (can_id & 0x7) | ((can_id << 2) & 0xffe0) | (3 << 3);
+ } else {
+ can_id = (frame->can_id & CAN_SFF_MASK) << 5;
+ if (rtr)
+ can_id |= 1 << 4;
+ }
+ out_be16(&regs->tx.idr1_0, can_id);
+
+ if (!rtr) {
+ void __iomem *data = &regs->tx.dsr1_0;
+ u16 *payload = (u16 *) frame->data;
+ /* It is safe to write into dsr[dlc+1] */
+ for (i = 0; i < (frame->can_dlc + 1) / 2; i++) {
+ out_be16(data, *payload++);
+ data += 2 + _MSCAN_RESERVED_DSR_SIZE;
+ }
+ }
+
+ out_8(&regs->tx.dlr, frame->can_dlc);
+ out_8(&regs->tx.tbpr, priv->cur_pri);
+
+ /* Start transmission. */
+ out_8(&regs->cantflg, 1 << buf_id);
+
+ if (!test_bit(F_TX_PROGRESS, &priv->flags))
+ dev->trans_start = jiffies;
+
+ list_add_tail(&priv->tx_queue[buf_id].list, &priv->tx_head);
+
+ can_put_echo_skb(skb, dev, buf_id);
+
+ /* Enable interrupt. */
+ priv->tx_active |= 1 << buf_id;
+ out_8(&regs->cantier, priv->tx_active);
+
+ return NETDEV_TX_OK;
+}
+
+/* This function returns the old state to see where we came from */
+static enum can_state check_set_state(struct net_device *dev, u8 canrflg)
+{
+ struct mscan_priv *priv = netdev_priv(dev);
+ enum can_state state, old_state = priv->can.state;
+
+ if (canrflg & MSCAN_CSCIF && old_state <= CAN_STATE_BUS_OFF) {
+ state = state_map[max(MSCAN_STATE_RX(canrflg),
+ MSCAN_STATE_TX(canrflg))];
+ priv->can.state = state;
+ }
+ return old_state;
+}
+
+static void mscan_get_rx_frame(struct net_device *dev, struct can_frame *frame)
+{
+ struct mscan_priv *priv = netdev_priv(dev);
+ struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
+ u32 can_id;
+ int i;
+
+ can_id = in_be16(&regs->rx.idr1_0);
+ if (can_id & (1 << 3)) {
+ frame->can_id = CAN_EFF_FLAG;
+ can_id = ((can_id << 16) | in_be16(&regs->rx.idr3_2));
+ can_id = ((can_id & 0xffe00000) |
+ ((can_id & 0x7ffff) << 2)) >> 2;
+ } else {
+ can_id >>= 4;
+ frame->can_id = 0;
+ }
+
+ frame->can_id |= can_id >> 1;
+ if (can_id & 1)
+ frame->can_id |= CAN_RTR_FLAG;
+ frame->can_dlc = in_8(&regs->rx.dlr) & 0xf;
+
+ if (!(frame->can_id & CAN_RTR_FLAG)) {
+ void __iomem *data = &regs->rx.dsr1_0;
+ u16 *payload = (u16 *) frame->data;
+ for (i = 0; i < (frame->can_dlc + 1) / 2; i++) {
+ *payload++ = in_be16(data);
+ data += 2 + _MSCAN_RESERVED_DSR_SIZE;
+ }
+ }
+
+ out_8(&regs->canrflg, MSCAN_RXF);
+}
+
+static void mscan_get_err_frame(struct net_device *dev, struct can_frame *frame,
+ u8 canrflg)
+{
+ struct mscan_priv *priv = netdev_priv(dev);
+ struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
+ struct net_device_stats *stats = &dev->stats;
+ enum can_state old_state;
+
+ dev_dbg(dev->dev.parent, "error interrupt (canrflg=%#x)\n", canrflg);
+ frame->can_id = CAN_ERR_FLAG;
+
+ if (canrflg & MSCAN_OVRIF) {
+ frame->can_id |= CAN_ERR_CRTL;
+ frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
+ stats->rx_over_errors++;
+ stats->rx_errors++;
+ } else
+ frame->data[1] = 0;
+
+ old_state = check_set_state(dev, canrflg);
+ /* State changed */
+ if (old_state != priv->can.state) {
+ switch (priv->can.state) {
+ case CAN_STATE_ERROR_WARNING:
+ frame->can_id |= CAN_ERR_CRTL;
+ priv->can.can_stats.error_warning++;
+ if ((priv->shadow_statflg & MSCAN_RSTAT_MSK) <
+ (canrflg & MSCAN_RSTAT_MSK))
+ frame->data[1] |= CAN_ERR_CRTL_RX_WARNING;
+
+ if ((priv->shadow_statflg & MSCAN_TSTAT_MSK) <
+ (canrflg & MSCAN_TSTAT_MSK))
+ frame->data[1] |= CAN_ERR_CRTL_TX_WARNING;
+ break;
+ case CAN_STATE_ERROR_PASSIVE:
+ frame->can_id |= CAN_ERR_CRTL;
+ priv->can.can_stats.error_passive++;
+ frame->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
+ break;
+ case CAN_STATE_BUS_OFF:
+ frame->can_id |= CAN_ERR_BUSOFF;
+ /*
+ * The MSCAN on the MPC5200 does recover from bus-off
+ * automatically. To avoid that we stop the chip doing
+ * a light-weight stop (we are in irq-context).
+ */
+ out_8(&regs->cantier, 0);
+ out_8(&regs->canrier, 0);
+ out_8(&regs->canctl0, in_8(&regs->canctl0) |
+ MSCAN_SLPRQ | MSCAN_INITRQ);
+ can_bus_off(dev);
+ break;
+ default:
+ break;
+ }
+ }
+ priv->shadow_statflg = canrflg & MSCAN_STAT_MSK;
+ frame->can_dlc = CAN_ERR_DLC;
+ out_8(&regs->canrflg, MSCAN_ERR_IF);
+}
+
+static int mscan_rx_poll(struct napi_struct *napi, int quota)
+{
+ struct mscan_priv *priv = container_of(napi, struct mscan_priv, napi);
+ struct net_device *dev = napi->dev;
+ struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
+ struct net_device_stats *stats = &dev->stats;
+ int npackets = 0;
+ int ret = 1;
+ struct sk_buff *skb;
+ struct can_frame *frame;
+ u8 canrflg;
+
+ while (npackets < quota && ((canrflg = in_8(&regs->canrflg)) &
+ (MSCAN_RXF | MSCAN_ERR_IF))) {
+
+ skb = alloc_can_skb(dev, &frame);
+ if (!skb) {
+ if (printk_ratelimit())
+ dev_notice(dev->dev.parent, "packet dropped\n");
+ stats->rx_dropped++;
+ out_8(&regs->canrflg, canrflg);
+ continue;
+ }
+
+ if (canrflg & MSCAN_RXF)
+ mscan_get_rx_frame(dev, frame);
+ else if (canrflg & MSCAN_ERR_IF)
+ mscan_get_err_frame(dev, frame, canrflg);
+
+ stats->rx_packets++;
+ stats->rx_bytes += frame->can_dlc;
+ npackets++;
+ netif_receive_skb(skb);
+ }
+
+ if (!(in_8(&regs->canrflg) & (MSCAN_RXF | MSCAN_ERR_IF))) {
+ napi_complete(&priv->napi);
+ clear_bit(F_RX_PROGRESS, &priv->flags);
+ if (priv->can.state < CAN_STATE_BUS_OFF)
+ out_8(&regs->canrier, priv->shadow_canrier);
+ ret = 0;
+ }
+ return ret;
+}
+
+static irqreturn_t mscan_isr(int irq, void *dev_id)
+{
+ struct net_device *dev = (struct net_device *)dev_id;
+ struct mscan_priv *priv = netdev_priv(dev);
+ struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
+ struct net_device_stats *stats = &dev->stats;
+ u8 cantier, cantflg, canrflg;
+ irqreturn_t ret = IRQ_NONE;
+
+ cantier = in_8(&regs->cantier) & MSCAN_TXE;
+ cantflg = in_8(&regs->cantflg) & cantier;
+
+ if (cantier && cantflg) {
+
+ struct list_head *tmp, *pos;
+
+ list_for_each_safe(pos, tmp, &priv->tx_head) {
+ struct tx_queue_entry *entry =
+ list_entry(pos, struct tx_queue_entry, list);
+ u8 mask = entry->mask;
+
+ if (!(cantflg & mask))
+ continue;
+
+ out_8(&regs->cantbsel, mask);
+ stats->tx_bytes += in_8(&regs->tx.dlr);
+ stats->tx_packets++;
+ can_get_echo_skb(dev, entry->id);
+ priv->tx_active &= ~mask;
+ list_del(pos);
+ }
+
+ if (list_empty(&priv->tx_head)) {
+ clear_bit(F_TX_WAIT_ALL, &priv->flags);
+ clear_bit(F_TX_PROGRESS, &priv->flags);
+ priv->cur_pri = 0;
+ } else
+ dev->trans_start = jiffies;
+
+ if (!test_bit(F_TX_WAIT_ALL, &priv->flags))
+ netif_wake_queue(dev);
+
+ out_8(&regs->cantier, priv->tx_active);
+ ret = IRQ_HANDLED;
+ }
+
+ canrflg = in_8(&regs->canrflg);
+ if ((canrflg & ~MSCAN_STAT_MSK) &&
+ !test_and_set_bit(F_RX_PROGRESS, &priv->flags)) {
+ if (canrflg & ~MSCAN_STAT_MSK) {
+ priv->shadow_canrier = in_8(&regs->canrier);
+ out_8(&regs->canrier, 0);
+ napi_schedule(&priv->napi);
+ ret = IRQ_HANDLED;
+ } else
+ clear_bit(F_RX_PROGRESS, &priv->flags);
+ }
+ return ret;
+}
+
+static int mscan_do_set_mode(struct net_device *dev, enum can_mode mode)
+{
+
+ struct mscan_priv *priv = netdev_priv(dev);
+ int ret = 0;
+
+ if (!priv->open_time)
+ return -EINVAL;
+
+ switch (mode) {
+ case CAN_MODE_SLEEP:
+ case CAN_MODE_STOP:
+ netif_stop_queue(dev);
+ mscan_set_mode(dev,
+ (mode ==
+ CAN_MODE_STOP) ? MSCAN_INIT_MODE :
+ MSCAN_SLEEP_MODE);
+ break;
+ case CAN_MODE_START:
+ if (priv->can.state <= CAN_STATE_BUS_OFF)
+ mscan_set_mode(dev, MSCAN_INIT_MODE);
+ ret = mscan_start(dev);
+ if (ret)
+ break;
+ if (netif_queue_stopped(dev))
+ netif_wake_queue(dev);
+ break;
+
+ default:
+ ret = -EOPNOTSUPP;
+ break;
+ }
+ return ret;
+}
+
+static int mscan_do_set_bittiming(struct net_device *dev)
+{
+ struct mscan_priv *priv = netdev_priv(dev);
+ struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
+ struct can_bittiming *bt = &priv->can.bittiming;
+ u8 btr0, btr1;
+
+ btr0 = BTR0_SET_BRP(bt->brp) | BTR0_SET_SJW(bt->sjw);
+ btr1 = (BTR1_SET_TSEG1(bt->prop_seg + bt->phase_seg1) |
+ BTR1_SET_TSEG2(bt->phase_seg2) |
+ BTR1_SET_SAM(priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES));
+
+ dev_info(dev->dev.parent, "setting BTR0=0x%02x BTR1=0x%02x\n",
+ btr0, btr1);
+
+ out_8(&regs->canbtr0, btr0);
+ out_8(&regs->canbtr1, btr1);
+
+ return 0;
+}
+
+static int mscan_open(struct net_device *dev)
+{
+ int ret;
+ struct mscan_priv *priv = netdev_priv(dev);
+ struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
+
+ /* common open */
+ ret = open_candev(dev);
+ if (ret)
+ return ret;
+
+ napi_enable(&priv->napi);
+
+ ret = request_irq(dev->irq, mscan_isr, 0, dev->name, dev);
+ if (ret < 0) {
+ napi_disable(&priv->napi);
+ printk(KERN_ERR "%s - failed to attach interrupt\n",
+ dev->name);
+ return ret;
+ }
+
+ priv->open_time = jiffies;
+
+ out_8(&regs->canctl1, in_8(&regs->canctl1) & ~MSCAN_LISTEN);
+
+ ret = mscan_start(dev);
+ if (ret)
+ return ret;
+
+ netif_start_queue(dev);
+
+ return 0;
+}
+
+static int mscan_close(struct net_device *dev)
+{
+ struct mscan_priv *priv = netdev_priv(dev);
+ struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
+
+ netif_stop_queue(dev);
+ napi_disable(&priv->napi);
+
+ out_8(&regs->cantier, 0);
+ out_8(&regs->canrier, 0);
+ mscan_set_mode(dev, MSCAN_INIT_MODE);
+ close_candev(dev);
+ free_irq(dev->irq, dev);
+ priv->open_time = 0;
+
+ return 0;
+}
+
+static const struct net_device_ops mscan_netdev_ops = {
+ .ndo_open = mscan_open,
+ .ndo_stop = mscan_close,
+ .ndo_start_xmit = mscan_start_xmit,
+};
+
+int register_mscandev(struct net_device *dev, int clock_src)
+{
+ struct mscan_priv *priv = netdev_priv(dev);
+ struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
+ u8 ctl1;
+
+ ctl1 = in_8(&regs->canctl1);
+ if (clock_src)
+ ctl1 |= MSCAN_CLKSRC;
+ else
+ ctl1 &= ~MSCAN_CLKSRC;
+
+ ctl1 |= MSCAN_CANE;
+ out_8(&regs->canctl1, ctl1);
+ udelay(100);
+
+ /* acceptance mask/acceptance code (accept everything) */
+ out_be16(&regs->canidar1_0, 0);
+ out_be16(&regs->canidar3_2, 0);
+ out_be16(&regs->canidar5_4, 0);
+ out_be16(&regs->canidar7_6, 0);
+
+ out_be16(&regs->canidmr1_0, 0xffff);
+ out_be16(&regs->canidmr3_2, 0xffff);
+ out_be16(&regs->canidmr5_4, 0xffff);
+ out_be16(&regs->canidmr7_6, 0xffff);
+ /* Two 32 bit Acceptance Filters */
+ out_8(&regs->canidac, MSCAN_AF_32BIT);
+
+ mscan_set_mode(dev, MSCAN_INIT_MODE);
+
+ return register_candev(dev);
+}
+EXPORT_SYMBOL_GPL(register_mscandev);
+
+void unregister_mscandev(struct net_device *dev)
+{
+ struct mscan_priv *priv = netdev_priv(dev);
+ struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base;
+ mscan_set_mode(dev, MSCAN_INIT_MODE);
+ out_8(&regs->canctl1, in_8(&regs->canctl1) & ~MSCAN_CANE);
+ unregister_candev(dev);
+}
+EXPORT_SYMBOL_GPL(unregister_mscandev);
+
+struct net_device *alloc_mscandev(void)
+{
+ struct net_device *dev;
+ struct mscan_priv *priv;
+ int i;
+
+ dev = alloc_candev(sizeof(struct mscan_priv), MSCAN_ECHO_SKB_MAX);
+ if (!dev)
+ return NULL;
+ priv = netdev_priv(dev);
+
+ dev->netdev_ops = &mscan_netdev_ops;
+
+ dev->flags |= IFF_ECHO; /* we support local echo */
+
+ netif_napi_add(dev, &priv->napi, mscan_rx_poll, 8);
+
+ priv->can.bittiming_const = &mscan_bittiming_const;
+ priv->can.do_set_bittiming = mscan_do_set_bittiming;
+ priv->can.do_set_mode = mscan_do_set_mode;
+
+ for (i = 0; i < TX_QUEUE_SIZE; i++) {
+ priv->tx_queue[i].id = i;
+ priv->tx_queue[i].mask = 1 << i;
+ }
+
+ return dev;
+}
+EXPORT_SYMBOL_GPL(alloc_mscandev);
+
+MODULE_AUTHOR("Andrey Volkov <avolkov@varma-el.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("CAN port driver for a MSCAN based chips");