scx200_32.c

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/*
 *  Copyright (c) 2001,2002 Christer Weinigel <[email protected]>
 *
 *  National Semiconductor SCx200 support.
 */

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/pci.h>

#include <linux/scx200.h>
#include <linux/scx200_gpio.h>

/* Verify that the configuration block really is there */
#define scx200_cb_probe(base) (inw((base) + SCx200_CBA) == (base))

MODULE_AUTHOR("Christer Weinigel <[email protected]>");
MODULE_DESCRIPTION("NatSemi SCx200 Driver");
MODULE_LICENSE("GPL");

unsigned scx200_gpio_base = 0;
unsigned long scx200_gpio_shadow[2];

unsigned scx200_cb_base = 0;

static struct pci_device_id scx200_tbl[] = {
    { PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SCx200_BRIDGE) },
    { PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SC1100_BRIDGE) },
    { PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SCx200_XBUS)   },
    { PCI_VDEVICE(NS, PCI_DEVICE_ID_NS_SC1100_XBUS)   },
    { },
};
MODULE_DEVICE_TABLE(pci,scx200_tbl);

static int __devinit scx200_probe(struct pci_dev *, const struct pci_device_id *);

static struct pci_driver scx200_pci_driver = {
    .name = "scx200",
    .id_table = scx200_tbl,
    .probe = scx200_probe,
};

static DEFINE_MUTEX(scx200_gpio_config_lock);

static void __devinit scx200_init_shadow(void)
{
    int bank;

    /* read the current values driven on the GPIO signals */
    for (bank = 0; bank < 2; ++bank)
        scx200_gpio_shadow[bank] = inl(scx200_gpio_base + 0x10 * bank);
}

static int __devinit scx200_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
    unsigned base;

    if (pdev->device == PCI_DEVICE_ID_NS_SCx200_BRIDGE ||
        pdev->device == PCI_DEVICE_ID_NS_SC1100_BRIDGE) {
        base = pci_resource_start(pdev, 0);
        pr_info("GPIO base 0x%x\n", base);

        if (!request_region(base, SCx200_GPIO_SIZE,
                    "NatSemi SCx200 GPIO")) {
            pr_err("can't allocate I/O for GPIOs\n");
            return -EBUSY;
        }

        scx200_gpio_base = base;
        scx200_init_shadow();

    } else {
        /* find the base of the Configuration Block */
        if (scx200_cb_probe(SCx200_CB_BASE_FIXED)) {
            scx200_cb_base = SCx200_CB_BASE_FIXED;
        } else {
            pci_read_config_dword(pdev, SCx200_CBA_SCRATCH, &base);
            if (scx200_cb_probe(base)) {
                scx200_cb_base = base;
            } else {
                pr_warn("Configuration Block not found\n");
                return -ENODEV;
            }
        }
        pr_info("Configuration Block base 0x%x\n", scx200_cb_base);
    }

    return 0;
}

u32 scx200_gpio_configure(unsigned index, u32 mask, u32 bits)
{
    u32 config, new_config;

    mutex_lock(&scx200_gpio_config_lock);

    outl(index, scx200_gpio_base + 0x20);
    config = inl(scx200_gpio_base + 0x24);

    new_config = (config & mask) | bits;
    outl(new_config, scx200_gpio_base + 0x24);

    mutex_unlock(&scx200_gpio_config_lock);

    return config;
}

static int __init scx200_init(void)
{
    pr_info("NatSemi SCx200 Driver\n");
    return pci_register_driver(&scx200_pci_driver);
}

static void __exit scx200_cleanup(void)
{
    pci_unregister_driver(&scx200_pci_driver);
    release_region(scx200_gpio_base, SCx200_GPIO_SIZE);
}

module_init(scx200_init);
module_exit(scx200_cleanup);

EXPORT_SYMBOL(scx200_gpio_base);
EXPORT_SYMBOL(scx200_gpio_shadow);
EXPORT_SYMBOL(scx200_gpio_configure);
EXPORT_SYMBOL(scx200_cb_base);