diff options
Diffstat (limited to 'kernel/drivers/net/can/sja1000/sja1000.c')
| -rw-r--r-- | kernel/drivers/net/can/sja1000/sja1000.c | 704 |
1 files changed, 704 insertions, 0 deletions
diff --git a/kernel/drivers/net/can/sja1000/sja1000.c b/kernel/drivers/net/can/sja1000/sja1000.c new file mode 100644 index 000000000..32bd7f451 --- /dev/null +++ b/kernel/drivers/net/can/sja1000/sja1000.c @@ -0,0 +1,704 @@ +/* + * 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. + * + */ + +#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/dev.h> +#include <linux/can/error.h> +#include <linux/can/led.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 const 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 void sja1000_write_cmdreg(struct sja1000_priv *priv, u8 val) +{ + unsigned long flags; + + /* + * The command register needs some locking and time to settle + * the write_reg() operation - especially on SMP systems. + */ + spin_lock_irqsave(&priv->cmdreg_lock, flags); + priv->write_reg(priv, SJA1000_CMR, val); + priv->read_reg(priv, SJA1000_SR); + spin_unlock_irqrestore(&priv->cmdreg_lock, flags); +} + +static int sja1000_is_absent(struct sja1000_priv *priv) +{ + return (priv->read_reg(priv, SJA1000_MOD) == 0xFF); +} + +static int sja1000_probe_chip(struct net_device *dev) +{ + struct sja1000_priv *priv = netdev_priv(dev); + + if (priv->reg_base && sja1000_is_absent(priv)) { + netdev_err(dev, "probing failed\n"); + 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(priv, SJA1000_MOD); + int i; + + /* disable interrupts */ + priv->write_reg(priv, SJA1000_IER, IRQ_OFF); + + for (i = 0; i < 100; i++) { + /* check reset bit */ + if (status & MOD_RM) { + priv->can.state = CAN_STATE_STOPPED; + return; + } + + /* reset chip */ + priv->write_reg(priv, SJA1000_MOD, MOD_RM); + udelay(10); + status = priv->read_reg(priv, SJA1000_MOD); + } + + netdev_err(dev, "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(priv, SJA1000_MOD); + u8 mod_reg_val = 0x00; + int i; + + for (i = 0; i < 100; i++) { + /* check reset bit */ + if ((status & MOD_RM) == 0) { + priv->can.state = CAN_STATE_ERROR_ACTIVE; + /* enable interrupts */ + if (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) + priv->write_reg(priv, SJA1000_IER, IRQ_ALL); + else + priv->write_reg(priv, SJA1000_IER, + IRQ_ALL & ~IRQ_BEI); + return; + } + + /* set chip to normal mode */ + if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY) + mod_reg_val |= MOD_LOM; + if (priv->can.ctrlmode & CAN_CTRLMODE_PRESUME_ACK) + mod_reg_val |= MOD_STM; + priv->write_reg(priv, SJA1000_MOD, mod_reg_val); + + udelay(10); + + status = priv->read_reg(priv, SJA1000_MOD); + } + + netdev_err(dev, "setting SJA1000 into normal mode failed!\n"); +} + +/* + * 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(priv, SJA1000_CDR, priv->cdr | CDR_PELICAN); + + /* set acceptance filter (accept all) */ + priv->write_reg(priv, SJA1000_ACCC0, 0x00); + priv->write_reg(priv, SJA1000_ACCC1, 0x00); + priv->write_reg(priv, SJA1000_ACCC2, 0x00); + priv->write_reg(priv, SJA1000_ACCC3, 0x00); + + priv->write_reg(priv, SJA1000_ACCM0, 0xFF); + priv->write_reg(priv, SJA1000_ACCM1, 0xFF); + priv->write_reg(priv, SJA1000_ACCM2, 0xFF); + priv->write_reg(priv, SJA1000_ACCM3, 0xFF); + + priv->write_reg(priv, SJA1000_OCR, priv->ocr | OCR_MODE_NORMAL); +} + +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); + + /* Initialize chip if uninitialized at this stage */ + if (!(priv->read_reg(priv, SJA1000_CDR) & CDR_PELICAN)) + chipset_init(dev); + + /* Clear error counters and error code capture */ + priv->write_reg(priv, SJA1000_TXERR, 0x0); + priv->write_reg(priv, SJA1000_RXERR, 0x0); + priv->read_reg(priv, SJA1000_ECC); + + /* leave reset mode */ + set_normal_mode(dev); +} + +static int sja1000_set_mode(struct net_device *dev, enum can_mode mode) +{ + 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; + + netdev_info(dev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1); + + priv->write_reg(priv, SJA1000_BTR0, btr0); + priv->write_reg(priv, SJA1000_BTR1, btr1); + + return 0; +} + +static int sja1000_get_berr_counter(const struct net_device *dev, + struct can_berr_counter *bec) +{ + struct sja1000_priv *priv = netdev_priv(dev); + + bec->txerr = priv->read_reg(priv, SJA1000_TXERR); + bec->rxerr = priv->read_reg(priv, SJA1000_RXERR); + + return 0; +} + +/* + * 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 netdev_tx_t sja1000_start_xmit(struct sk_buff *skb, + struct net_device *dev) +{ + struct sja1000_priv *priv = netdev_priv(dev); + struct can_frame *cf = (struct can_frame *)skb->data; + uint8_t fi; + uint8_t dlc; + canid_t id; + uint8_t dreg; + u8 cmd_reg_val = 0x00; + int i; + + if (can_dropped_invalid_skb(dev, skb)) + return NETDEV_TX_OK; + + netif_stop_queue(dev); + + fi = dlc = cf->can_dlc; + id = cf->can_id; + + if (id & CAN_RTR_FLAG) + fi |= SJA1000_FI_RTR; + + if (id & CAN_EFF_FLAG) { + fi |= SJA1000_FI_FF; + dreg = SJA1000_EFF_BUF; + priv->write_reg(priv, SJA1000_FI, fi); + priv->write_reg(priv, SJA1000_ID1, (id & 0x1fe00000) >> 21); + priv->write_reg(priv, SJA1000_ID2, (id & 0x001fe000) >> 13); + priv->write_reg(priv, SJA1000_ID3, (id & 0x00001fe0) >> 5); + priv->write_reg(priv, SJA1000_ID4, (id & 0x0000001f) << 3); + } else { + dreg = SJA1000_SFF_BUF; + priv->write_reg(priv, SJA1000_FI, fi); + priv->write_reg(priv, SJA1000_ID1, (id & 0x000007f8) >> 3); + priv->write_reg(priv, SJA1000_ID2, (id & 0x00000007) << 5); + } + + for (i = 0; i < dlc; i++) + priv->write_reg(priv, dreg++, cf->data[i]); + + can_put_echo_skb(skb, dev, 0); + + if (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT) + cmd_reg_val |= CMD_AT; + + if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) + cmd_reg_val |= CMD_SRR; + else + cmd_reg_val |= CMD_TR; + + sja1000_write_cmdreg(priv, cmd_reg_val); + + return NETDEV_TX_OK; +} + +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; + int i; + + /* create zero'ed CAN frame buffer */ + skb = alloc_can_skb(dev, &cf); + if (skb == NULL) + return; + + fi = priv->read_reg(priv, SJA1000_FI); + + if (fi & SJA1000_FI_FF) { + /* extended frame format (EFF) */ + dreg = SJA1000_EFF_BUF; + id = (priv->read_reg(priv, SJA1000_ID1) << 21) + | (priv->read_reg(priv, SJA1000_ID2) << 13) + | (priv->read_reg(priv, SJA1000_ID3) << 5) + | (priv->read_reg(priv, SJA1000_ID4) >> 3); + id |= CAN_EFF_FLAG; + } else { + /* standard frame format (SFF) */ + dreg = SJA1000_SFF_BUF; + id = (priv->read_reg(priv, SJA1000_ID1) << 3) + | (priv->read_reg(priv, SJA1000_ID2) >> 5); + } + + cf->can_dlc = get_can_dlc(fi & 0x0F); + if (fi & SJA1000_FI_RTR) { + id |= CAN_RTR_FLAG; + } else { + for (i = 0; i < cf->can_dlc; i++) + cf->data[i] = priv->read_reg(priv, dreg++); + } + + cf->can_id = id; + + /* release receive buffer */ + sja1000_write_cmdreg(priv, CMD_RRB); + + netif_rx(skb); + + stats->rx_packets++; + stats->rx_bytes += cf->can_dlc; + + can_led_event(dev, CAN_LED_EVENT_RX); +} + +static int sja1000_err(struct net_device *dev, uint8_t isrc, uint8_t status) +{ + 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; + enum can_state rx_state, tx_state; + unsigned int rxerr, txerr; + uint8_t ecc, alc; + + skb = alloc_can_err_skb(dev, &cf); + if (skb == NULL) + return -ENOMEM; + + txerr = priv->read_reg(priv, SJA1000_TXERR); + rxerr = priv->read_reg(priv, SJA1000_RXERR); + + cf->data[6] = txerr; + cf->data[7] = rxerr; + + if (isrc & IRQ_DOI) { + /* data overrun interrupt */ + netdev_dbg(dev, "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++; + sja1000_write_cmdreg(priv, CMD_CDO); /* clear bit */ + } + + if (isrc & IRQ_EI) { + /* error warning interrupt */ + netdev_dbg(dev, "error warning interrupt\n"); + + if (status & SR_BS) + state = CAN_STATE_BUS_OFF; + 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(priv, SJA1000_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 occurred during transmission? */ + if ((ecc & ECC_DIR) == 0) + cf->data[2] |= CAN_ERR_PROT_TX; + } + if (isrc & IRQ_EPI) { + /* error passive interrupt */ + netdev_dbg(dev, "error passive interrupt\n"); + + if (state == CAN_STATE_ERROR_PASSIVE) + state = CAN_STATE_ERROR_WARNING; + else + state = CAN_STATE_ERROR_PASSIVE; + } + if (isrc & IRQ_ALI) { + /* arbitration lost interrupt */ + netdev_dbg(dev, "arbitration lost interrupt\n"); + alc = priv->read_reg(priv, SJA1000_ALC); + priv->can.can_stats.arbitration_lost++; + stats->tx_errors++; + cf->can_id |= CAN_ERR_LOSTARB; + cf->data[0] = alc & 0x1f; + } + + if (state != priv->can.state) { + tx_state = txerr >= rxerr ? state : 0; + rx_state = txerr <= rxerr ? state : 0; + + can_change_state(dev, cf, tx_state, rx_state); + + if(state == CAN_STATE_BUS_OFF) + can_bus_off(dev); + } + + netif_rx(skb); + + 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; + + if (priv->pre_irq) + priv->pre_irq(priv); + + /* Shared interrupts and IRQ off? */ + if (priv->read_reg(priv, SJA1000_IER) == IRQ_OFF) + goto out; + + while ((isrc = priv->read_reg(priv, SJA1000_IR)) && + (n < SJA1000_MAX_IRQ)) { + + status = priv->read_reg(priv, SJA1000_SR); + /* check for absent controller due to hw unplug */ + if (status == 0xFF && sja1000_is_absent(priv)) + goto out; + + if (isrc & IRQ_WUI) + netdev_warn(dev, "wakeup interrupt\n"); + + if (isrc & IRQ_TI) { + /* transmission buffer released */ + if (priv->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT && + !(status & SR_TCS)) { + stats->tx_errors++; + can_free_echo_skb(dev, 0); + } else { + /* transmission complete */ + stats->tx_bytes += + priv->read_reg(priv, SJA1000_FI) & 0xf; + stats->tx_packets++; + can_get_echo_skb(dev, 0); + } + netif_wake_queue(dev); + can_led_event(dev, CAN_LED_EVENT_TX); + } + if (isrc & IRQ_RI) { + /* receive interrupt */ + while (status & SR_RBS) { + sja1000_rx(dev); + status = priv->read_reg(priv, SJA1000_SR); + /* check for absent controller */ + if (status == 0xFF && sja1000_is_absent(priv)) + goto out; + } + } + if (isrc & (IRQ_DOI | IRQ_EI | IRQ_BEI | IRQ_EPI | IRQ_ALI)) { + /* error interrupt */ + if (sja1000_err(dev, isrc, status)) + break; + } + n++; + } +out: + if (priv->post_irq) + priv->post_irq(priv); + + if (n >= SJA1000_MAX_IRQ) + netdev_dbg(dev, "%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) { + close_candev(dev); + return -EAGAIN; + } + } + + /* init and start chi */ + sja1000_start(dev); + + can_led_event(dev, CAN_LED_EVENT_OPEN); + + 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); + + can_led_event(dev, CAN_LED_EVENT_STOP); + + 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, + SJA1000_ECHO_SKB_MAX); + 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; + priv->can.do_get_berr_counter = sja1000_get_berr_counter; + priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK | + CAN_CTRLMODE_LISTENONLY | + CAN_CTRLMODE_3_SAMPLES | + CAN_CTRLMODE_ONE_SHOT | + CAN_CTRLMODE_BERR_REPORTING | + CAN_CTRLMODE_PRESUME_ACK; + + spin_lock_init(&priv->cmdreg_lock); + + 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, + .ndo_change_mtu = can_change_mtu, +}; + +int register_sja1000dev(struct net_device *dev) +{ + int ret; + + 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); + + ret = register_candev(dev); + + if (!ret) + devm_can_led_init(dev); + + return ret; +} +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); |