can: Driver for the SJA1000 CAN controller
This patch adds the generic Socket-CAN driver for the Philips SJA1000
full CAN controller.
Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/can/sja1000/sja1000.c b/drivers/net/can/sja1000/sja1000.c
new file mode 100644
index 0000000..05b38dd
--- /dev/null
+++ b/drivers/net/can/sja1000/sja1000.c
@@ -0,0 +1,637 @@
+/*
+ * sja1000.c - Philips SJA1000 network device driver
+ *
+ * Copyright (c) 2003 Matthias Brukner, Trajet Gmbh, Rebenring 33,
+ * 38106 Braunschweig, GERMANY
+ *
+ * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Volkswagen nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * Alternatively, provided that this notice is retained in full, this
+ * software may be distributed under the terms of the GNU General
+ * Public License ("GPL") version 2, in which case the provisions of the
+ * GPL apply INSTEAD OF those given above.
+ *
+ * The provided data structures and external interfaces from this code
+ * are not restricted to be used by modules with a GPL compatible license.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * Send feedback to <socketcan-users@lists.berlios.de>
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/interrupt.h>
+#include <linux/ptrace.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/if_ether.h>
+#include <linux/skbuff.h>
+#include <linux/delay.h>
+
+#include <linux/can.h>
+#include <linux/can/dev.h>
+#include <linux/can/error.h>
+#include <linux/can/dev.h>
+
+#include "sja1000.h"
+
+#define DRV_NAME "sja1000"
+
+MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_DESCRIPTION(DRV_NAME "CAN netdevice driver");
+
+static struct can_bittiming_const sja1000_bittiming_const = {
+ .name = DRV_NAME,
+ .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 sja1000_probe_chip(struct net_device *dev)
+{
+ struct sja1000_priv *priv = netdev_priv(dev);
+
+ if (dev->base_addr && (priv->read_reg(dev, 0) == 0xFF)) {
+ printk(KERN_INFO "%s: probing @0x%lX failed\n",
+ DRV_NAME, dev->base_addr);
+ return 0;
+ }
+ return -1;
+}
+
+static void set_reset_mode(struct net_device *dev)
+{
+ struct sja1000_priv *priv = netdev_priv(dev);
+ unsigned char status = priv->read_reg(dev, REG_MOD);
+ int i;
+
+ /* disable interrupts */
+ priv->write_reg(dev, REG_IER, IRQ_OFF);
+
+ for (i = 0; i < 100; i++) {
+ /* check reset bit */
+ if (status & MOD_RM) {
+ priv->can.state = CAN_STATE_STOPPED;
+ return;
+ }
+
+ priv->write_reg(dev, REG_MOD, MOD_RM); /* reset chip */
+ udelay(10);
+ status = priv->read_reg(dev, REG_MOD);
+ }
+
+ dev_err(dev->dev.parent, "setting SJA1000 into reset mode failed!\n");
+}
+
+static void set_normal_mode(struct net_device *dev)
+{
+ struct sja1000_priv *priv = netdev_priv(dev);
+ unsigned char status = priv->read_reg(dev, REG_MOD);
+ int i;
+
+ for (i = 0; i < 100; i++) {
+ /* check reset bit */
+ if ((status & MOD_RM) == 0) {
+ priv->can.state = CAN_STATE_ERROR_ACTIVE;
+ /* enable all interrupts */
+ priv->write_reg(dev, REG_IER, IRQ_ALL);
+ return;
+ }
+
+ /* set chip to normal mode */
+ priv->write_reg(dev, REG_MOD, 0x00);
+ udelay(10);
+ status = priv->read_reg(dev, REG_MOD);
+ }
+
+ dev_err(dev->dev.parent, "setting SJA1000 into normal mode failed!\n");
+}
+
+static void sja1000_start(struct net_device *dev)
+{
+ struct sja1000_priv *priv = netdev_priv(dev);
+
+ /* leave reset mode */
+ if (priv->can.state != CAN_STATE_STOPPED)
+ set_reset_mode(dev);
+
+ /* Clear error counters and error code capture */
+ priv->write_reg(dev, REG_TXERR, 0x0);
+ priv->write_reg(dev, REG_RXERR, 0x0);
+ priv->read_reg(dev, REG_ECC);
+
+ /* leave reset mode */
+ set_normal_mode(dev);
+}
+
+static int sja1000_set_mode(struct net_device *dev, enum can_mode mode)
+{
+ struct sja1000_priv *priv = netdev_priv(dev);
+
+ if (!priv->open_time)
+ return -EINVAL;
+
+ switch (mode) {
+ case CAN_MODE_START:
+ sja1000_start(dev);
+ if (netif_queue_stopped(dev))
+ netif_wake_queue(dev);
+ break;
+
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ return 0;
+}
+
+static int sja1000_set_bittiming(struct net_device *dev)
+{
+ struct sja1000_priv *priv = netdev_priv(dev);
+ struct can_bittiming *bt = &priv->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 (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
+ btr1 |= 0x80;
+
+ dev_info(dev->dev.parent,
+ "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
+
+ priv->write_reg(dev, REG_BTR0, btr0);
+ priv->write_reg(dev, REG_BTR1, btr1);
+
+ return 0;
+}
+
+/*
+ * initialize SJA1000 chip:
+ * - reset chip
+ * - set output mode
+ * - set baudrate
+ * - enable interrupts
+ * - start operating mode
+ */
+static void chipset_init(struct net_device *dev)
+{
+ struct sja1000_priv *priv = netdev_priv(dev);
+
+ /* set clock divider and output control register */
+ priv->write_reg(dev, REG_CDR, priv->cdr | CDR_PELICAN);
+
+ /* set acceptance filter (accept all) */
+ priv->write_reg(dev, REG_ACCC0, 0x00);
+ priv->write_reg(dev, REG_ACCC1, 0x00);
+ priv->write_reg(dev, REG_ACCC2, 0x00);
+ priv->write_reg(dev, REG_ACCC3, 0x00);
+
+ priv->write_reg(dev, REG_ACCM0, 0xFF);
+ priv->write_reg(dev, REG_ACCM1, 0xFF);
+ priv->write_reg(dev, REG_ACCM2, 0xFF);
+ priv->write_reg(dev, REG_ACCM3, 0xFF);
+
+ priv->write_reg(dev, REG_OCR, priv->ocr | OCR_MODE_NORMAL);
+}
+
+/*
+ * transmit a CAN message
+ * message layout in the sk_buff should be like this:
+ * xx xx xx xx ff ll 00 11 22 33 44 55 66 77
+ * [ can-id ] [flags] [len] [can data (up to 8 bytes]
+ */
+static int sja1000_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct sja1000_priv *priv = netdev_priv(dev);
+ struct net_device_stats *stats = &dev->stats;
+ struct can_frame *cf = (struct can_frame *)skb->data;
+ uint8_t fi;
+ uint8_t dlc;
+ canid_t id;
+ uint8_t dreg;
+ int i;
+
+ netif_stop_queue(dev);
+
+ fi = dlc = cf->can_dlc;
+ id = cf->can_id;
+
+ if (id & CAN_RTR_FLAG)
+ fi |= FI_RTR;
+
+ if (id & CAN_EFF_FLAG) {
+ fi |= FI_FF;
+ dreg = EFF_BUF;
+ priv->write_reg(dev, REG_FI, fi);
+ priv->write_reg(dev, REG_ID1, (id & 0x1fe00000) >> (5 + 16));
+ priv->write_reg(dev, REG_ID2, (id & 0x001fe000) >> (5 + 8));
+ priv->write_reg(dev, REG_ID3, (id & 0x00001fe0) >> 5);
+ priv->write_reg(dev, REG_ID4, (id & 0x0000001f) << 3);
+ } else {
+ dreg = SFF_BUF;
+ priv->write_reg(dev, REG_FI, fi);
+ priv->write_reg(dev, REG_ID1, (id & 0x000007f8) >> 3);
+ priv->write_reg(dev, REG_ID2, (id & 0x00000007) << 5);
+ }
+
+ for (i = 0; i < dlc; i++)
+ priv->write_reg(dev, dreg++, cf->data[i]);
+
+ stats->tx_bytes += dlc;
+ dev->trans_start = jiffies;
+
+ can_put_echo_skb(skb, dev, 0);
+
+ priv->write_reg(dev, REG_CMR, CMD_TR);
+
+ return 0;
+}
+
+static void sja1000_rx(struct net_device *dev)
+{
+ struct sja1000_priv *priv = netdev_priv(dev);
+ struct net_device_stats *stats = &dev->stats;
+ struct can_frame *cf;
+ struct sk_buff *skb;
+ uint8_t fi;
+ uint8_t dreg;
+ canid_t id;
+ uint8_t dlc;
+ int i;
+
+ skb = dev_alloc_skb(sizeof(struct can_frame));
+ if (skb == NULL)
+ return;
+ skb->dev = dev;
+ skb->protocol = htons(ETH_P_CAN);
+
+ fi = priv->read_reg(dev, REG_FI);
+ dlc = fi & 0x0F;
+
+ if (fi & FI_FF) {
+ /* extended frame format (EFF) */
+ dreg = EFF_BUF;
+ id = (priv->read_reg(dev, REG_ID1) << (5 + 16))
+ | (priv->read_reg(dev, REG_ID2) << (5 + 8))
+ | (priv->read_reg(dev, REG_ID3) << 5)
+ | (priv->read_reg(dev, REG_ID4) >> 3);
+ id |= CAN_EFF_FLAG;
+ } else {
+ /* standard frame format (SFF) */
+ dreg = SFF_BUF;
+ id = (priv->read_reg(dev, REG_ID1) << 3)
+ | (priv->read_reg(dev, REG_ID2) >> 5);
+ }
+
+ if (fi & FI_RTR)
+ id |= CAN_RTR_FLAG;
+
+ cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
+ memset(cf, 0, sizeof(struct can_frame));
+ cf->can_id = id;
+ cf->can_dlc = dlc;
+ for (i = 0; i < dlc; i++)
+ cf->data[i] = priv->read_reg(dev, dreg++);
+
+ while (i < 8)
+ cf->data[i++] = 0;
+
+ /* release receive buffer */
+ priv->write_reg(dev, REG_CMR, CMD_RRB);
+
+ netif_rx(skb);
+
+ dev->last_rx = jiffies;
+ stats->rx_packets++;
+ stats->rx_bytes += dlc;
+}
+
+static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status)
+{
+ struct sja1000_priv *priv = netdev_priv(dev);
+ struct net_device_stats *stats = &dev->stats;
+ struct can_frame *cf;
+ struct sk_buff *skb;
+ enum can_state state = priv->can.state;
+ uint8_t ecc, alc;
+
+ skb = dev_alloc_skb(sizeof(struct can_frame));
+ if (skb == NULL)
+ return -ENOMEM;
+ skb->dev = dev;
+ 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 (isrc & IRQ_DOI) {
+ /* data overrun interrupt */
+ dev_dbg(dev->dev.parent, "data overrun interrupt\n");
+ cf->can_id |= CAN_ERR_CRTL;
+ cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
+ stats->rx_over_errors++;
+ stats->rx_errors++;
+ priv->write_reg(dev, REG_CMR, CMD_CDO); /* clear bit */
+ }
+
+ if (isrc & IRQ_EI) {
+ /* error warning interrupt */
+ dev_dbg(dev->dev.parent, "error warning interrupt\n");
+
+ if (status & SR_BS) {
+ state = CAN_STATE_BUS_OFF;
+ cf->can_id |= CAN_ERR_BUSOFF;
+ can_bus_off(dev);
+ } else if (status & SR_ES) {
+ state = CAN_STATE_ERROR_WARNING;
+ } else
+ state = CAN_STATE_ERROR_ACTIVE;
+ }
+ if (isrc & IRQ_BEI) {
+ /* bus error interrupt */
+ priv->can.can_stats.bus_error++;
+ stats->rx_errors++;
+
+ ecc = priv->read_reg(dev, REG_ECC);
+
+ cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+
+ switch (ecc & ECC_MASK) {
+ case ECC_BIT:
+ cf->data[2] |= CAN_ERR_PROT_BIT;
+ break;
+ case ECC_FORM:
+ cf->data[2] |= CAN_ERR_PROT_FORM;
+ break;
+ case ECC_STUFF:
+ cf->data[2] |= CAN_ERR_PROT_STUFF;
+ break;
+ default:
+ cf->data[2] |= CAN_ERR_PROT_UNSPEC;
+ cf->data[3] = ecc & ECC_SEG;
+ break;
+ }
+ /* Error occured during transmission? */
+ if ((ecc & ECC_DIR) == 0)
+ cf->data[2] |= CAN_ERR_PROT_TX;
+ }
+ if (isrc & IRQ_EPI) {
+ /* error passive interrupt */
+ dev_dbg(dev->dev.parent, "error passive interrupt\n");
+ if (status & SR_ES)
+ state = CAN_STATE_ERROR_PASSIVE;
+ else
+ state = CAN_STATE_ERROR_ACTIVE;
+ }
+ if (isrc & IRQ_ALI) {
+ /* arbitration lost interrupt */
+ dev_dbg(dev->dev.parent, "arbitration lost interrupt\n");
+ alc = priv->read_reg(dev, REG_ALC);
+ priv->can.can_stats.arbitration_lost++;
+ stats->rx_errors++;
+ cf->can_id |= CAN_ERR_LOSTARB;
+ cf->data[0] = alc & 0x1f;
+ }
+
+ if (state != priv->can.state && (state == CAN_STATE_ERROR_WARNING ||
+ state == CAN_STATE_ERROR_PASSIVE)) {
+ uint8_t rxerr = priv->read_reg(dev, REG_RXERR);
+ uint8_t txerr = priv->read_reg(dev, REG_TXERR);
+ cf->can_id |= CAN_ERR_CRTL;
+ if (state == CAN_STATE_ERROR_WARNING) {
+ priv->can.can_stats.error_warning++;
+ cf->data[1] = (txerr > rxerr) ?
+ CAN_ERR_CRTL_TX_WARNING :
+ CAN_ERR_CRTL_RX_WARNING;
+ } else {
+ priv->can.can_stats.error_passive++;
+ cf->data[1] = (txerr > rxerr) ?
+ CAN_ERR_CRTL_TX_PASSIVE :
+ CAN_ERR_CRTL_RX_PASSIVE;
+ }
+ }
+
+ priv->can.state = state;
+
+ netif_rx(skb);
+
+ dev->last_rx = jiffies;
+ stats->rx_packets++;
+ stats->rx_bytes += cf->can_dlc;
+
+ return 0;
+}
+
+irqreturn_t sja1000_interrupt(int irq, void *dev_id)
+{
+ struct net_device *dev = (struct net_device *)dev_id;
+ struct sja1000_priv *priv = netdev_priv(dev);
+ struct net_device_stats *stats = &dev->stats;
+ uint8_t isrc, status;
+ int n = 0;
+
+ /* Shared interrupts and IRQ off? */
+ if (priv->read_reg(dev, REG_IER) == IRQ_OFF)
+ return IRQ_NONE;
+
+ if (priv->pre_irq)
+ priv->pre_irq(dev);
+
+ while ((isrc = priv->read_reg(dev, REG_IR)) && (n < SJA1000_MAX_IRQ)) {
+ n++;
+ status = priv->read_reg(dev, REG_SR);
+
+ if (isrc & IRQ_WUI)
+ dev_warn(dev->dev.parent, "wakeup interrupt\n");
+
+ if (isrc & IRQ_TI) {
+ /* transmission complete interrupt */
+ stats->tx_packets++;
+ can_get_echo_skb(dev, 0);
+ netif_wake_queue(dev);
+ }
+ if (isrc & IRQ_RI) {
+ /* receive interrupt */
+ while (status & SR_RBS) {
+ sja1000_rx(dev);
+ status = priv->read_reg(dev, REG_SR);
+ }
+ }
+ if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) {
+ /* error interrupt */
+ if (sja1000_err(dev, isrc, status))
+ break;
+ }
+ }
+
+ if (priv->post_irq)
+ priv->post_irq(dev);
+
+ if (n >= SJA1000_MAX_IRQ)
+ dev_dbg(dev->dev.parent, "%d messages handled in ISR", n);
+
+ return (n) ? IRQ_HANDLED : IRQ_NONE;
+}
+EXPORT_SYMBOL_GPL(sja1000_interrupt);
+
+static int sja1000_open(struct net_device *dev)
+{
+ struct sja1000_priv *priv = netdev_priv(dev);
+ int err;
+
+ /* set chip into reset mode */
+ set_reset_mode(dev);
+
+ /* common open */
+ err = open_candev(dev);
+ if (err)
+ return err;
+
+ /* register interrupt handler, if not done by the device driver */
+ if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER)) {
+ err = request_irq(dev->irq, &sja1000_interrupt, priv->irq_flags,
+ dev->name, (void *)dev);
+ if (err) {
+ return -EAGAIN;
+ close_candev(dev);
+ }
+ }
+
+ /* init and start chi */
+ sja1000_start(dev);
+ priv->open_time = jiffies;
+
+ netif_start_queue(dev);
+
+ return 0;
+}
+
+static int sja1000_close(struct net_device *dev)
+{
+ struct sja1000_priv *priv = netdev_priv(dev);
+
+ netif_stop_queue(dev);
+ set_reset_mode(dev);
+
+ if (!(priv->flags & SJA1000_CUSTOM_IRQ_HANDLER))
+ free_irq(dev->irq, (void *)dev);
+
+ close_candev(dev);
+
+ priv->open_time = 0;
+
+ return 0;
+}
+
+struct net_device *alloc_sja1000dev(int sizeof_priv)
+{
+ struct net_device *dev;
+ struct sja1000_priv *priv;
+
+ dev = alloc_candev(sizeof(struct sja1000_priv) + sizeof_priv);
+ if (!dev)
+ return NULL;
+
+ priv = netdev_priv(dev);
+
+ priv->dev = dev;
+ priv->can.bittiming_const = &sja1000_bittiming_const;
+ priv->can.do_set_bittiming = sja1000_set_bittiming;
+ priv->can.do_set_mode = sja1000_set_mode;
+
+ if (sizeof_priv)
+ priv->priv = (void *)priv + sizeof(struct sja1000_priv);
+
+ return dev;
+}
+EXPORT_SYMBOL_GPL(alloc_sja1000dev);
+
+void free_sja1000dev(struct net_device *dev)
+{
+ free_candev(dev);
+}
+EXPORT_SYMBOL_GPL(free_sja1000dev);
+
+static const struct net_device_ops sja1000_netdev_ops = {
+ .ndo_open = sja1000_open,
+ .ndo_stop = sja1000_close,
+ .ndo_start_xmit = sja1000_start_xmit,
+};
+
+int register_sja1000dev(struct net_device *dev)
+{
+ if (!sja1000_probe_chip(dev))
+ return -ENODEV;
+
+ dev->flags |= IFF_ECHO; /* we support local echo */
+ dev->netdev_ops = &sja1000_netdev_ops;
+
+ set_reset_mode(dev);
+ chipset_init(dev);
+
+ return register_candev(dev);
+}
+EXPORT_SYMBOL_GPL(register_sja1000dev);
+
+void unregister_sja1000dev(struct net_device *dev)
+{
+ set_reset_mode(dev);
+ unregister_candev(dev);
+}
+EXPORT_SYMBOL_GPL(unregister_sja1000dev);
+
+static __init int sja1000_init(void)
+{
+ printk(KERN_INFO "%s CAN netdevice driver\n", DRV_NAME);
+
+ return 0;
+}
+
+module_init(sja1000_init);
+
+static __exit void sja1000_exit(void)
+{
+ printk(KERN_INFO "%s: driver removed\n", DRV_NAME);
+}
+
+module_exit(sja1000_exit);