peak_pci.c

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/*
 * Copyright (C) 2007, 2011 Wolfgang Grandegger <[email protected]>
 * Copyright (C) 2012 Stephane Grosjean <[email protected]>
 *
 * Derived from the PCAN project file driver/src/pcan_pci.c:
 *
 * Copyright (C) 2001-2006  PEAK System-Technik GmbH
 *
 * 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.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/io.h>
#include <linux/i2c.h>
#include <linux/i2c-algo-bit.h>
#include <linux/can.h>
#include <linux/can/dev.h>

#include "sja1000.h"

MODULE_AUTHOR("Stephane Grosjean <[email protected]>");
MODULE_DESCRIPTION("Socket-CAN driver for PEAK PCAN PCI family cards");
MODULE_SUPPORTED_DEVICE("PEAK PCAN PCI/PCIe/PCIeC miniPCI CAN cards");
MODULE_SUPPORTED_DEVICE("PEAK PCAN miniPCIe/cPCI PC/104+ PCI/104e CAN Cards");
MODULE_LICENSE("GPL v2");

#define DRV_NAME  "peak_pci"

struct peak_pciec_card;
struct peak_pci_chan {
    void __iomem *cfg_base;     /* Common for all channels */
    struct net_device *prev_dev;    /* Chain of network devices */
    u16 icr_mask;           /* Interrupt mask for fast ack */
    struct peak_pciec_card *pciec_card; /* only for PCIeC LEDs */
};

#define PEAK_PCI_CAN_CLOCK  (16000000 / 2)

#define PEAK_PCI_CDR        (CDR_CBP | CDR_CLKOUT_MASK)
#define PEAK_PCI_OCR        OCR_TX0_PUSHPULL

/*
 * Important PITA registers
 */
#define PITA_ICR        0x00    /* Interrupt control register */
#define PITA_GPIOICR        0x18    /* GPIO interface control register */
#define PITA_MISC       0x1C    /* Miscellaneous register */

#define PEAK_PCI_CFG_SIZE   0x1000  /* Size of the config PCI bar */
#define PEAK_PCI_CHAN_SIZE  0x0400  /* Size used by the channel */

#define PEAK_PCI_VENDOR_ID  0x001C  /* The PCI device and vendor IDs */
#define PEAK_PCI_DEVICE_ID  0x0001  /* for PCI/PCIe slot cards */
#define PEAK_PCIEC_DEVICE_ID    0x0002  /* for ExpressCard slot cards */
#define PEAK_PCIE_DEVICE_ID 0x0003  /* for nextgen PCIe slot cards */
#define PEAK_CPCI_DEVICE_ID 0x0004  /* for nextgen cPCI slot cards */
#define PEAK_MPCI_DEVICE_ID 0x0005  /* for nextgen miniPCI slot cards */
#define PEAK_PC_104P_DEVICE_ID  0x0006  /* PCAN-PC/104+ cards */
#define PEAK_PCI_104E_DEVICE_ID 0x0007  /* PCAN-PCI/104 Express cards */
#define PEAK_MPCIE_DEVICE_ID    0x0008  /* The miniPCIe slot cards */

#define PEAK_PCI_CHAN_MAX   4

static const u16 peak_pci_icr_masks[PEAK_PCI_CHAN_MAX] = {
    0x02, 0x01, 0x40, 0x80
};

static DEFINE_PCI_DEVICE_TABLE(peak_pci_tbl) = {
    {PEAK_PCI_VENDOR_ID, PEAK_PCI_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
    {PEAK_PCI_VENDOR_ID, PEAK_PCIE_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
    {PEAK_PCI_VENDOR_ID, PEAK_MPCI_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
    {PEAK_PCI_VENDOR_ID, PEAK_MPCIE_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
    {PEAK_PCI_VENDOR_ID, PEAK_PC_104P_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
    {PEAK_PCI_VENDOR_ID, PEAK_PCI_104E_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
    {PEAK_PCI_VENDOR_ID, PEAK_CPCI_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
#ifdef CONFIG_CAN_PEAK_PCIEC
    {PEAK_PCI_VENDOR_ID, PEAK_PCIEC_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
#endif
    {0,}
};

MODULE_DEVICE_TABLE(pci, peak_pci_tbl);

#ifdef CONFIG_CAN_PEAK_PCIEC
/*
 * PCAN-ExpressCard needs I2C bit-banging configuration option.
 */

/* GPIOICR byte access offsets */
#define PITA_GPOUT      0x18    /* GPx output value */
#define PITA_GPIN       0x19    /* GPx input value */
#define PITA_GPOEN      0x1A    /* configure GPx as ouput pin */

/* I2C GP bits */
#define PITA_GPIN_SCL       0x01    /* Serial Clock Line */
#define PITA_GPIN_SDA       0x04    /* Serial DAta line */

#define PCA9553_1_SLAVEADDR (0xC4 >> 1)

/* PCA9553 LS0 fields values */
enum {
    PCA9553_LOW,
    PCA9553_HIGHZ,
    PCA9553_PWM0,
    PCA9553_PWM1
};

/* LEDs control */
#define PCA9553_ON      PCA9553_LOW
#define PCA9553_OFF     PCA9553_HIGHZ
#define PCA9553_SLOW        PCA9553_PWM0
#define PCA9553_FAST        PCA9553_PWM1

#define PCA9553_LED(c)      (1 << (c))
#define PCA9553_LED_STATE(s, c) ((s) << ((c) << 1))

#define PCA9553_LED_ON(c)   PCA9553_LED_STATE(PCA9553_ON, c)
#define PCA9553_LED_OFF(c)  PCA9553_LED_STATE(PCA9553_OFF, c)
#define PCA9553_LED_SLOW(c) PCA9553_LED_STATE(PCA9553_SLOW, c)
#define PCA9553_LED_FAST(c) PCA9553_LED_STATE(PCA9553_FAST, c)
#define PCA9553_LED_MASK(c) PCA9553_LED_STATE(0x03, c)

#define PCA9553_LED_OFF_ALL (PCA9553_LED_OFF(0) | PCA9553_LED_OFF(1))

#define PCA9553_LS0_INIT    0x40 /* initial value (!= from 0x00) */

struct peak_pciec_chan {
    struct net_device *netdev;
    unsigned long prev_rx_bytes;
    unsigned long prev_tx_bytes;
};

struct peak_pciec_card {
    void __iomem *cfg_base;     /* Common for all channels */
    void __iomem *reg_base;     /* first channel base address */
    u8 led_cache;           /* leds state cache */

    /* PCIExpressCard i2c data */
    struct i2c_algo_bit_data i2c_bit;
    struct i2c_adapter led_chip;
    struct delayed_work led_work;   /* led delayed work */
    int chan_count;
    struct peak_pciec_chan channel[PEAK_PCI_CHAN_MAX];
};

/* "normal" pci register write callback is overloaded for leds control */
static void peak_pci_write_reg(const struct sja1000_priv *priv,
                   int port, u8 val);

static inline void pita_set_scl_highz(struct peak_pciec_card *card)
{
    u8 gp_outen = readb(card->cfg_base + PITA_GPOEN) & ~PITA_GPIN_SCL;
    writeb(gp_outen, card->cfg_base + PITA_GPOEN);
}

static inline void pita_set_sda_highz(struct peak_pciec_card *card)
{
    u8 gp_outen = readb(card->cfg_base + PITA_GPOEN) & ~PITA_GPIN_SDA;
    writeb(gp_outen, card->cfg_base + PITA_GPOEN);
}

static void peak_pciec_init_pita_gpio(struct peak_pciec_card *card)
{
    /* raise SCL & SDA GPIOs to high-Z */
    pita_set_scl_highz(card);
    pita_set_sda_highz(card);
}

static void pita_setsda(void *data, int state)
{
    struct peak_pciec_card *card = (struct peak_pciec_card *)data;
    u8 gp_out, gp_outen;

    /* set output sda always to 0 */
    gp_out = readb(card->cfg_base + PITA_GPOUT) & ~PITA_GPIN_SDA;
    writeb(gp_out, card->cfg_base + PITA_GPOUT);

    /* control output sda with GPOEN */
    gp_outen = readb(card->cfg_base + PITA_GPOEN);
    if (state)
        gp_outen &= ~PITA_GPIN_SDA;
    else
        gp_outen |= PITA_GPIN_SDA;

    writeb(gp_outen, card->cfg_base + PITA_GPOEN);
}

static void pita_setscl(void *data, int state)
{
    struct peak_pciec_card *card = (struct peak_pciec_card *)data;
    u8 gp_out, gp_outen;

    /* set output scl always to 0 */
    gp_out = readb(card->cfg_base + PITA_GPOUT) & ~PITA_GPIN_SCL;
    writeb(gp_out, card->cfg_base + PITA_GPOUT);

    /* control output scl with GPOEN */
    gp_outen = readb(card->cfg_base + PITA_GPOEN);
    if (state)
        gp_outen &= ~PITA_GPIN_SCL;
    else
        gp_outen |= PITA_GPIN_SCL;

    writeb(gp_outen, card->cfg_base + PITA_GPOEN);
}

static int pita_getsda(void *data)
{
    struct peak_pciec_card *card = (struct peak_pciec_card *)data;

    /* set tristate */
    pita_set_sda_highz(card);

    return (readb(card->cfg_base + PITA_GPIN) & PITA_GPIN_SDA) ? 1 : 0;
}

static int pita_getscl(void *data)
{
    struct peak_pciec_card *card = (struct peak_pciec_card *)data;

    /* set tristate */
    pita_set_scl_highz(card);

    return (readb(card->cfg_base + PITA_GPIN) & PITA_GPIN_SCL) ? 1 : 0;
}

/*
 * write commands to the LED chip though the I2C-bus of the PCAN-PCIeC
 */
static int peak_pciec_write_pca9553(struct peak_pciec_card *card,
                    u8 offset, u8 data)
{
    u8 buffer[2] = {
        offset,
        data
    };
    struct i2c_msg msg = {
        .addr = PCA9553_1_SLAVEADDR,
        .len = 2,
        .buf = buffer,
    };
    int ret;

    /* cache led mask */
    if ((offset == 5) && (data == card->led_cache))
        return 0;

    ret = i2c_transfer(&card->led_chip, &msg, 1);
    if (ret < 0)
        return ret;

    if (offset == 5)
        card->led_cache = data;

    return 0;
}

/*
 * delayed work callback used to control the LEDs
 */
static void peak_pciec_led_work(struct work_struct *work)
{
    struct peak_pciec_card *card =
        container_of(work, struct peak_pciec_card, led_work.work);
    struct net_device *netdev;
    u8 new_led = card->led_cache;
    int i, up_count = 0;

    /* first check what is to do */
    for (i = 0; i < card->chan_count; i++) {
        /* default is: not configured */
        new_led &= ~PCA9553_LED_MASK(i);
        new_led |= PCA9553_LED_ON(i);

        netdev = card->channel[i].netdev;
        if (!netdev || !(netdev->flags & IFF_UP))
            continue;

        up_count++;

        /* no activity (but configured) */
        new_led &= ~PCA9553_LED_MASK(i);
        new_led |= PCA9553_LED_SLOW(i);

        /* if bytes counters changed, set fast blinking led */
        if (netdev->stats.rx_bytes != card->channel[i].prev_rx_bytes) {
            card->channel[i].prev_rx_bytes = netdev->stats.rx_bytes;
            new_led &= ~PCA9553_LED_MASK(i);
            new_led |= PCA9553_LED_FAST(i);
        }
        if (netdev->stats.tx_bytes != card->channel[i].prev_tx_bytes) {
            card->channel[i].prev_tx_bytes = netdev->stats.tx_bytes;
            new_led &= ~PCA9553_LED_MASK(i);
            new_led |= PCA9553_LED_FAST(i);
        }
    }

    /* check if LS0 settings changed, only update i2c if so */
    peak_pciec_write_pca9553(card, 5, new_led);

    /* restart timer (except if no more configured channels) */
    if (up_count)
        schedule_delayed_work(&card->led_work, HZ);
}

/*
 * set LEDs blinking state
 */
static void peak_pciec_set_leds(struct peak_pciec_card *card, u8 led_mask, u8 s)
{
    u8 new_led = card->led_cache;
    int i;

    /* first check what is to do */
    for (i = 0; i < card->chan_count; i++)
        if (led_mask & PCA9553_LED(i)) {
            new_led &= ~PCA9553_LED_MASK(i);
            new_led |= PCA9553_LED_STATE(s, i);
        }

    /* check if LS0 settings changed, only update i2c if so */
    peak_pciec_write_pca9553(card, 5, new_led);
}

/*
 * start one second delayed work to control LEDs
 */
static void peak_pciec_start_led_work(struct peak_pciec_card *card)
{
    if (!delayed_work_pending(&card->led_work))
        schedule_delayed_work(&card->led_work, HZ);
}

/*
 * stop LEDs delayed work
 */
static void peak_pciec_stop_led_work(struct peak_pciec_card *card)
{
    cancel_delayed_work_sync(&card->led_work);
}

/*
 * initialize the PCA9553 4-bit I2C-bus LED chip
 */
static int peak_pciec_init_leds(struct peak_pciec_card *card)
{
    int err;

    /* prescaler for frequency 0: "SLOW" = 1 Hz = "44" */
    err = peak_pciec_write_pca9553(card, 1, 44 / 1);
    if (err)
        return err;

    /* duty cycle 0: 50% */
    err = peak_pciec_write_pca9553(card, 2, 0x80);
    if (err)
        return err;

    /* prescaler for frequency 1: "FAST" = 5 Hz */
    err = peak_pciec_write_pca9553(card, 3, 44 / 5);
    if (err)
        return err;

    /* duty cycle 1: 50% */
    err = peak_pciec_write_pca9553(card, 4, 0x80);
    if (err)
        return err;

    /* switch LEDs to initial state */
    return peak_pciec_write_pca9553(card, 5, PCA9553_LS0_INIT);
}

/*
 * restore LEDs state to off peak_pciec_leds_exit
 */
static void peak_pciec_leds_exit(struct peak_pciec_card *card)
{
    /* switch LEDs to off */
    peak_pciec_write_pca9553(card, 5, PCA9553_LED_OFF_ALL);
}

/*
 * normal write sja1000 register method overloaded to catch when controller
 * is started or stopped, to control leds
 */
static void peak_pciec_write_reg(const struct sja1000_priv *priv,
                 int port, u8 val)
{
    struct peak_pci_chan *chan = priv->priv;
    struct peak_pciec_card *card = chan->pciec_card;
    int c = (priv->reg_base - card->reg_base) / PEAK_PCI_CHAN_SIZE;

    /* sja1000 register changes control the leds state */
    if (port == REG_MOD)
        switch (val) {
        case MOD_RM:
            /* Reset Mode: set led on */
            peak_pciec_set_leds(card, PCA9553_LED(c), PCA9553_ON);
            break;
        case 0x00:
            /* Normal Mode: led slow blinking and start led timer */
            peak_pciec_set_leds(card, PCA9553_LED(c), PCA9553_SLOW);
            peak_pciec_start_led_work(card);
            break;
        default:
            break;
        }

    /* call base function */
    peak_pci_write_reg(priv, port, val);
}

static struct i2c_algo_bit_data peak_pciec_i2c_bit_ops = {
    .setsda = pita_setsda,
    .setscl = pita_setscl,
    .getsda = pita_getsda,
    .getscl = pita_getscl,
    .udelay = 10,
    .timeout = HZ,
};

static int peak_pciec_probe(struct pci_dev *pdev, struct net_device *dev)
{
    struct sja1000_priv *priv = netdev_priv(dev);
    struct peak_pci_chan *chan = priv->priv;
    struct peak_pciec_card *card;
    int err;

    /* copy i2c object address from 1st channel */
    if (chan->prev_dev) {
        struct sja1000_priv *prev_priv = netdev_priv(chan->prev_dev);
        struct peak_pci_chan *prev_chan = prev_priv->priv;

        card = prev_chan->pciec_card;
        if (!card)
            return -ENODEV;

    /* channel is the first one: do the init part */
    } else {
        /* create the bit banging I2C adapter structure */
        card = kzalloc(sizeof(struct peak_pciec_card), GFP_KERNEL);
        if (!card) {
            dev_err(&pdev->dev,
                 "failed allocating memory for i2c chip\n");
            return -ENOMEM;
        }

        card->cfg_base = chan->cfg_base;
        card->reg_base = priv->reg_base;

        card->led_chip.owner = THIS_MODULE;
        card->led_chip.dev.parent = &pdev->dev;
        card->led_chip.algo_data = &card->i2c_bit;
        strncpy(card->led_chip.name, "peak_i2c",
            sizeof(card->led_chip.name));

        card->i2c_bit = peak_pciec_i2c_bit_ops;
        card->i2c_bit.udelay = 10;
        card->i2c_bit.timeout = HZ;
        card->i2c_bit.data = card;

        peak_pciec_init_pita_gpio(card);

        err = i2c_bit_add_bus(&card->led_chip);
        if (err) {
            dev_err(&pdev->dev, "i2c init failed\n");
            goto pciec_init_err_1;
        }

        err = peak_pciec_init_leds(card);
        if (err) {
            dev_err(&pdev->dev, "leds hardware init failed\n");
            goto pciec_init_err_2;
        }

        INIT_DELAYED_WORK(&card->led_work, peak_pciec_led_work);
        /* PCAN-ExpressCard needs its own callback for leds */
        priv->write_reg = peak_pciec_write_reg;
    }

    chan->pciec_card = card;
    card->channel[card->chan_count++].netdev = dev;

    return 0;

pciec_init_err_2:
    i2c_del_adapter(&card->led_chip);

pciec_init_err_1:
    peak_pciec_init_pita_gpio(card);
    kfree(card);

    return err;
}

static void peak_pciec_remove(struct peak_pciec_card *card)
{
    peak_pciec_stop_led_work(card);
    peak_pciec_leds_exit(card);
    i2c_del_adapter(&card->led_chip);
    peak_pciec_init_pita_gpio(card);
    kfree(card);
}

#else /* CONFIG_CAN_PEAK_PCIEC */

/*
 * Placebo functions when PCAN-ExpressCard support is not selected
 */
static inline int peak_pciec_probe(struct pci_dev *pdev, struct net_device *dev)
{
    return -ENODEV;
}

static inline void peak_pciec_remove(struct peak_pciec_card *card)
{
}
#endif /* CONFIG_CAN_PEAK_PCIEC */

static u8 peak_pci_read_reg(const struct sja1000_priv *priv, int port)
{
    return readb(priv->reg_base + (port << 2));
}

static void peak_pci_write_reg(const struct sja1000_priv *priv,
                   int port, u8 val)
{
    writeb(val, priv->reg_base + (port << 2));
}

static void peak_pci_post_irq(const struct sja1000_priv *priv)
{
    struct peak_pci_chan *chan = priv->priv;
    u16 icr;

    /* Select and clear in PITA stored interrupt */
    icr = readw(chan->cfg_base + PITA_ICR);
    if (icr & chan->icr_mask)
        writew(chan->icr_mask, chan->cfg_base + PITA_ICR);
}

static int __devinit peak_pci_probe(struct pci_dev *pdev,
                    const struct pci_device_id *ent)
{
    struct sja1000_priv *priv;
    struct peak_pci_chan *chan;
    struct net_device *dev;
    void __iomem *cfg_base, *reg_base;
    u16 sub_sys_id, icr;
    int i, err, channels;

    err = pci_enable_device(pdev);
    if (err)
        return err;

    err = pci_request_regions(pdev, DRV_NAME);
    if (err)
        goto failure_disable_pci;

    err = pci_read_config_word(pdev, 0x2e, &sub_sys_id);
    if (err)
        goto failure_release_regions;

    dev_dbg(&pdev->dev, "probing device %04x:%04x:%04x\n",
        pdev->vendor, pdev->device, sub_sys_id);

    err = pci_write_config_word(pdev, 0x44, 0);
    if (err)
        goto failure_release_regions;

    if (sub_sys_id >= 12)
        channels = 4;
    else if (sub_sys_id >= 10)
        channels = 3;
    else if (sub_sys_id >= 4)
        channels = 2;
    else
        channels = 1;

    cfg_base = pci_iomap(pdev, 0, PEAK_PCI_CFG_SIZE);
    if (!cfg_base) {
        dev_err(&pdev->dev, "failed to map PCI resource #0\n");
        err = -ENOMEM;
        goto failure_release_regions;
    }

    reg_base = pci_iomap(pdev, 1, PEAK_PCI_CHAN_SIZE * channels);
    if (!reg_base) {
        dev_err(&pdev->dev, "failed to map PCI resource #1\n");
        err = -ENOMEM;
        goto failure_unmap_cfg_base;
    }

    /* Set GPIO control register */
    writew(0x0005, cfg_base + PITA_GPIOICR + 2);
    /* Enable all channels of this card */
    writeb(0x00, cfg_base + PITA_GPIOICR);
    /* Toggle reset */
    writeb(0x05, cfg_base + PITA_MISC + 3);
    mdelay(5);
    /* Leave parport mux mode */
    writeb(0x04, cfg_base + PITA_MISC + 3);

    icr = readw(cfg_base + PITA_ICR + 2);

    for (i = 0; i < channels; i++) {
        dev = alloc_sja1000dev(sizeof(struct peak_pci_chan));
        if (!dev) {
            err = -ENOMEM;
            goto failure_remove_channels;
        }

        priv = netdev_priv(dev);
        chan = priv->priv;

        chan->cfg_base = cfg_base;
        priv->reg_base = reg_base + i * PEAK_PCI_CHAN_SIZE;

        priv->read_reg = peak_pci_read_reg;
        priv->write_reg = peak_pci_write_reg;
        priv->post_irq = peak_pci_post_irq;

        priv->can.clock.freq = PEAK_PCI_CAN_CLOCK;
        priv->ocr = PEAK_PCI_OCR;
        priv->cdr = PEAK_PCI_CDR;
        /* Neither a slave nor a single device distributes the clock */
        if (channels == 1 || i > 0)
            priv->cdr |= CDR_CLK_OFF;

        /* Setup interrupt handling */
        priv->irq_flags = IRQF_SHARED;
        dev->irq = pdev->irq;

        chan->icr_mask = peak_pci_icr_masks[i];
        icr |= chan->icr_mask;

        SET_NETDEV_DEV(dev, &pdev->dev);

        /* Create chain of SJA1000 devices */
        chan->prev_dev = pci_get_drvdata(pdev);
        pci_set_drvdata(pdev, dev);

        /*
         * PCAN-ExpressCard needs some additional i2c init.
         * This must be done *before* register_sja1000dev() but
         * *after* devices linkage
         */
        if (pdev->device == PEAK_PCIEC_DEVICE_ID) {
            err = peak_pciec_probe(pdev, dev);
            if (err) {
                dev_err(&pdev->dev,
                    "failed to probe device (err %d)\n",
                    err);
                goto failure_free_dev;
            }
        }

        err = register_sja1000dev(dev);
        if (err) {
            dev_err(&pdev->dev, "failed to register device\n");
            goto failure_free_dev;
        }

        dev_info(&pdev->dev,
             "%s at reg_base=0x%p cfg_base=0x%p irq=%d\n",
             dev->name, priv->reg_base, chan->cfg_base, dev->irq);
    }

    /* Enable interrupts */
    writew(icr, cfg_base + PITA_ICR + 2);

    return 0;

failure_free_dev:
    pci_set_drvdata(pdev, chan->prev_dev);
    free_sja1000dev(dev);

failure_remove_channels:
    /* Disable interrupts */
    writew(0x0, cfg_base + PITA_ICR + 2);

    chan = NULL;
    for (dev = pci_get_drvdata(pdev); dev; dev = chan->prev_dev) {
        unregister_sja1000dev(dev);
        free_sja1000dev(dev);
        priv = netdev_priv(dev);
        chan = priv->priv;
    }

    /* free any PCIeC resources too */
    if (chan && chan->pciec_card)
        peak_pciec_remove(chan->pciec_card);

    pci_iounmap(pdev, reg_base);

failure_unmap_cfg_base:
    pci_iounmap(pdev, cfg_base);

failure_release_regions:
    pci_release_regions(pdev);

failure_disable_pci:
    pci_disable_device(pdev);

    return err;
}

static void __devexit peak_pci_remove(struct pci_dev *pdev)
{
    struct net_device *dev = pci_get_drvdata(pdev); /* Last device */
    struct sja1000_priv *priv = netdev_priv(dev);
    struct peak_pci_chan *chan = priv->priv;
    void __iomem *cfg_base = chan->cfg_base;
    void __iomem *reg_base = priv->reg_base;

    /* Disable interrupts */
    writew(0x0, cfg_base + PITA_ICR + 2);

    /* Loop over all registered devices */
    while (1) {
        dev_info(&pdev->dev, "removing device %s\n", dev->name);
        unregister_sja1000dev(dev);
        free_sja1000dev(dev);
        dev = chan->prev_dev;

        if (!dev) {
            /* do that only for first channel */
            if (chan->pciec_card)
                peak_pciec_remove(chan->pciec_card);
            break;
        }
        priv = netdev_priv(dev);
        chan = priv->priv;
    }

    pci_iounmap(pdev, reg_base);
    pci_iounmap(pdev, cfg_base);
    pci_release_regions(pdev);
    pci_disable_device(pdev);

    pci_set_drvdata(pdev, NULL);
}

static struct pci_driver peak_pci_driver = {
    .name = DRV_NAME,
    .id_table = peak_pci_tbl,
    .probe = peak_pci_probe,
    .remove = __devexit_p(peak_pci_remove),
};

module_pci_driver(peak_pci_driver);