rsrc_iodyn.c

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/*
 * rsrc_iodyn.c -- Resource management routines for MEM-static sockets.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * The initial developer of the original code is David A. Hinds
 * <[email protected]>.  Portions created by David A. Hinds
 * are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.
 *
 * (C) 1999     David A. Hinds
 */

#include <linux/slab.h>
#include <linux/module.h>
#include <linux/kernel.h>

#include <pcmcia/ss.h>
#include <pcmcia/cistpl.h>
#include "cs_internal.h"


struct pcmcia_align_data {
    unsigned long   mask;
    unsigned long   offset;
};

static resource_size_t pcmcia_align(void *align_data,
                const struct resource *res,
                resource_size_t size, resource_size_t align)
{
    struct pcmcia_align_data *data = align_data;
    resource_size_t start;

    start = (res->start & ~data->mask) + data->offset;
    if (start < res->start)
        start += data->mask + 1;

#ifdef CONFIG_X86
    if (res->flags & IORESOURCE_IO) {
        if (start & 0x300)
            start = (start + 0x3ff) & ~0x3ff;
    }
#endif

#ifdef CONFIG_M68K
    if (res->flags & IORESOURCE_IO) {
        if ((res->start + size - 1) >= 1024)
            start = res->end;
    }
#endif

    return start;
}


static struct resource *__iodyn_find_io_region(struct pcmcia_socket *s,
                    unsigned long base, int num,
                    unsigned long align)
{
    struct resource *res = pcmcia_make_resource(0, num, IORESOURCE_IO,
                        dev_name(&s->dev));
    struct pcmcia_align_data data;
    unsigned long min = base;
    int ret;

    data.mask = align - 1;
    data.offset = base & data.mask;

#ifdef CONFIG_PCI
    if (s->cb_dev) {
        ret = pci_bus_alloc_resource(s->cb_dev->bus, res, num, 1,
                         min, 0, pcmcia_align, &data);
    } else
#endif
        ret = allocate_resource(&ioport_resource, res, num, min, ~0UL,
                    1, pcmcia_align, &data);

    if (ret != 0) {
        kfree(res);
        res = NULL;
    }
    return res;
}

static int iodyn_find_io(struct pcmcia_socket *s, unsigned int attr,
            unsigned int *base, unsigned int num,
            unsigned int align, struct resource **parent)
{
    int i, ret = 0;

    /* Check for an already-allocated window that must conflict with
     * what was asked for.  It is a hack because it does not catch all
     * potential conflicts, just the most obvious ones.
     */
    for (i = 0; i < MAX_IO_WIN; i++) {
        if (!s->io[i].res)
            continue;

        if (!*base)
            continue;

        if ((s->io[i].res->start & (align-1)) == *base)
            return -EBUSY;
    }

    for (i = 0; i < MAX_IO_WIN; i++) {
        struct resource *res = s->io[i].res;
        unsigned int try;

        if (res && (res->flags & IORESOURCE_BITS) !=
            (attr & IORESOURCE_BITS))
            continue;

        if (!res) {
            if (align == 0)
                align = 0x10000;

            res = s->io[i].res = __iodyn_find_io_region(s, *base,
                                num, align);
            if (!res)
                return -EINVAL;

            *base = res->start;
            s->io[i].res->flags =
                ((res->flags & ~IORESOURCE_BITS) |
                    (attr & IORESOURCE_BITS));
            s->io[i].InUse = num;
            *parent = res;
            return 0;
        }

        /* Try to extend top of window */
        try = res->end + 1;
        if ((*base == 0) || (*base == try)) {
            if (adjust_resource(s->io[i].res, res->start,
                        resource_size(res) + num))
                continue;
            *base = try;
            s->io[i].InUse += num;
            *parent = res;
            return 0;
        }

        /* Try to extend bottom of window */
        try = res->start - num;
        if ((*base == 0) || (*base == try)) {
            if (adjust_resource(s->io[i].res,
                        res->start - num,
                        resource_size(res) + num))
                continue;
            *base = try;
            s->io[i].InUse += num;
            *parent = res;
            return 0;
        }
    }

    return -EINVAL;
}


struct pccard_resource_ops pccard_iodyn_ops = {
    .validate_mem = NULL,
    .find_io = iodyn_find_io,
    .find_mem = NULL,
    .init = static_init,
    .exit = NULL,
};
EXPORT_SYMBOL(pccard_iodyn_ops);