sja1000_platform.c

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/*
 * Copyright (C) 2005 Sascha Hauer, Pengutronix
 * Copyright (C) 2007 Wolfgang Grandegger <[email protected]>
 *
 * 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/netdevice.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/irq.h>
#include <linux/can/dev.h>
#include <linux/can/platform/sja1000.h>
#include <linux/io.h>

#include "sja1000.h"

#define DRV_NAME "sja1000_platform"

MODULE_AUTHOR("Sascha Hauer <[email protected]>");
MODULE_DESCRIPTION("Socket-CAN driver for SJA1000 on the platform bus");
MODULE_LICENSE("GPL v2");

static u8 sp_read_reg8(const struct sja1000_priv *priv, int reg)
{
    return ioread8(priv->reg_base + reg);
}

static void sp_write_reg8(const struct sja1000_priv *priv, int reg, u8 val)
{
    iowrite8(val, priv->reg_base + reg);
}

static u8 sp_read_reg16(const struct sja1000_priv *priv, int reg)
{
    return ioread8(priv->reg_base + reg * 2);
}

static void sp_write_reg16(const struct sja1000_priv *priv, int reg, u8 val)
{
    iowrite8(val, priv->reg_base + reg * 2);
}

static u8 sp_read_reg32(const struct sja1000_priv *priv, int reg)
{
    return ioread8(priv->reg_base + reg * 4);
}

static void sp_write_reg32(const struct sja1000_priv *priv, int reg, u8 val)
{
    iowrite8(val, priv->reg_base + reg * 4);
}

static int sp_probe(struct platform_device *pdev)
{
    int err;
    void __iomem *addr;
    struct net_device *dev;
    struct sja1000_priv *priv;
    struct resource *res_mem, *res_irq;
    struct sja1000_platform_data *pdata;

    pdata = pdev->dev.platform_data;
    if (!pdata) {
        dev_err(&pdev->dev, "No platform data provided!\n");
        err = -ENODEV;
        goto exit;
    }

    res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    res_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
    if (!res_mem || !res_irq) {
        err = -ENODEV;
        goto exit;
    }

    if (!request_mem_region(res_mem->start, resource_size(res_mem),
                DRV_NAME)) {
        err = -EBUSY;
        goto exit;
    }

    addr = ioremap_nocache(res_mem->start, resource_size(res_mem));
    if (!addr) {
        err = -ENOMEM;
        goto exit_release;
    }

    dev = alloc_sja1000dev(0);
    if (!dev) {
        err = -ENOMEM;
        goto exit_iounmap;
    }
    priv = netdev_priv(dev);

    dev->irq = res_irq->start;
    priv->irq_flags = res_irq->flags & IRQF_TRIGGER_MASK;
    if (res_irq->flags & IORESOURCE_IRQ_SHAREABLE)
        priv->irq_flags |= IRQF_SHARED;
    priv->reg_base = addr;
    /* The CAN clock frequency is half the oscillator clock frequency */
    priv->can.clock.freq = pdata->osc_freq / 2;
    priv->ocr = pdata->ocr;
    priv->cdr = pdata->cdr;

    switch (res_mem->flags & IORESOURCE_MEM_TYPE_MASK) {
    case IORESOURCE_MEM_32BIT:
        priv->read_reg = sp_read_reg32;
        priv->write_reg = sp_write_reg32;
        break;
    case IORESOURCE_MEM_16BIT:
        priv->read_reg = sp_read_reg16;
        priv->write_reg = sp_write_reg16;
        break;
    case IORESOURCE_MEM_8BIT:
    default:
        priv->read_reg = sp_read_reg8;
        priv->write_reg = sp_write_reg8;
        break;
    }

    dev_set_drvdata(&pdev->dev, dev);
    SET_NETDEV_DEV(dev, &pdev->dev);

    err = register_sja1000dev(dev);
    if (err) {
        dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
            DRV_NAME, err);
        goto exit_free;
    }

    dev_info(&pdev->dev, "%s device registered (reg_base=%p, irq=%d)\n",
         DRV_NAME, priv->reg_base, dev->irq);
    return 0;

 exit_free:
    free_sja1000dev(dev);
 exit_iounmap:
    iounmap(addr);
 exit_release:
    release_mem_region(res_mem->start, resource_size(res_mem));
 exit:
    return err;
}

static int sp_remove(struct platform_device *pdev)
{
    struct net_device *dev = dev_get_drvdata(&pdev->dev);
    struct sja1000_priv *priv = netdev_priv(dev);
    struct resource *res;

    unregister_sja1000dev(dev);
    dev_set_drvdata(&pdev->dev, NULL);

    if (priv->reg_base)
        iounmap(priv->reg_base);

    res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    release_mem_region(res->start, resource_size(res));

    free_sja1000dev(dev);

    return 0;
}

static struct platform_driver sp_driver = {
    .probe = sp_probe,
    .remove = sp_remove,
    .driver = {
        .name = DRV_NAME,
        .owner = THIS_MODULE,
    },
};

module_platform_driver(sp_driver);