core.c

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/*
 *  ISA Plug & Play support
 *  Copyright (c) by Jaroslav Kysela <[email protected]>
 *
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *  Changelog:
 *  2000-01-01  Added quirks handling for buggy hardware
 *      Peter Denison <[email protected]>
 *  2000-06-14  Added isapnp_probe_devs() and isapnp_activate_dev()
 *      Christoph Hellwig <[email protected]>
 *  2001-06-03  Added release_region calls to correspond with
 *      request_region calls when a failure occurs.  Also
 *      added KERN_* constants to printk() calls.
 *  2001-11-07  Added isapnp_{,un}register_driver calls along the lines
 *              of the pci driver interface
 *              Kai Germaschewski <[email protected]>
 *  2002-06-06  Made the use of dma channel 0 configurable
 *              Gerald Teschl <[email protected]>
 *  2002-10-06  Ported to PnP Layer - Adam Belay <[email protected]>
 *  2003-08-11  Resource Management Updates - Adam Belay <[email protected]>
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/isapnp.h>
#include <linux/mutex.h>
#include <asm/io.h>

#include "../base.h"

#if 0
#define ISAPNP_REGION_OK
#endif

int isapnp_disable;     /* Disable ISA PnP */
static int isapnp_rdp;      /* Read Data Port */
static int isapnp_reset = 1;    /* reset all PnP cards (deactivate) */
static int isapnp_verbose = 1;  /* verbose mode */

MODULE_AUTHOR("Jaroslav Kysela <[email protected]>");
MODULE_DESCRIPTION("Generic ISA Plug & Play support");
module_param(isapnp_disable, int, 0);
MODULE_PARM_DESC(isapnp_disable, "ISA Plug & Play disable");
module_param(isapnp_rdp, int, 0);
MODULE_PARM_DESC(isapnp_rdp, "ISA Plug & Play read data port");
module_param(isapnp_reset, int, 0);
MODULE_PARM_DESC(isapnp_reset, "ISA Plug & Play reset all cards");
module_param(isapnp_verbose, int, 0);
MODULE_PARM_DESC(isapnp_verbose, "ISA Plug & Play verbose mode");
MODULE_LICENSE("GPL");

#define _PIDXR      0x279
#define _PNPWRP     0xa79

/* short tags */
#define _STAG_PNPVERNO      0x01
#define _STAG_LOGDEVID      0x02
#define _STAG_COMPATDEVID   0x03
#define _STAG_IRQ       0x04
#define _STAG_DMA       0x05
#define _STAG_STARTDEP      0x06
#define _STAG_ENDDEP        0x07
#define _STAG_IOPORT        0x08
#define _STAG_FIXEDIO       0x09
#define _STAG_VENDOR        0x0e
#define _STAG_END       0x0f
/* long tags */
#define _LTAG_MEMRANGE      0x81
#define _LTAG_ANSISTR       0x82
#define _LTAG_UNICODESTR    0x83
#define _LTAG_VENDOR        0x84
#define _LTAG_MEM32RANGE    0x85
#define _LTAG_FIXEDMEM32RANGE   0x86

/* Logical device control and configuration registers */

#define ISAPNP_CFG_ACTIVATE 0x30    /* byte */
#define ISAPNP_CFG_MEM      0x40    /* 4 * dword */
#define ISAPNP_CFG_PORT     0x60    /* 8 * word */
#define ISAPNP_CFG_IRQ      0x70    /* 2 * word */
#define ISAPNP_CFG_DMA      0x74    /* 2 * byte */

/*
 * Sizes of ISAPNP logical device configuration register sets.
 * See PNP-ISA-v1.0a.pdf, Appendix A.
 */
#define ISAPNP_MAX_MEM      4
#define ISAPNP_MAX_PORT     8
#define ISAPNP_MAX_IRQ      2
#define ISAPNP_MAX_DMA      2

static unsigned char isapnp_checksum_value;
static DEFINE_MUTEX(isapnp_cfg_mutex);
static int isapnp_csn_count;

/* some prototypes */

static inline void write_data(unsigned char x)
{
    outb(x, _PNPWRP);
}

static inline void write_address(unsigned char x)
{
    outb(x, _PIDXR);
    udelay(20);
}

static inline unsigned char read_data(void)
{
    unsigned char val = inb(isapnp_rdp);
    return val;
}

unsigned char isapnp_read_byte(unsigned char idx)
{
    write_address(idx);
    return read_data();
}

static unsigned short isapnp_read_word(unsigned char idx)
{
    unsigned short val;

    val = isapnp_read_byte(idx);
    val = (val << 8) + isapnp_read_byte(idx + 1);
    return val;
}

void isapnp_write_byte(unsigned char idx, unsigned char val)
{
    write_address(idx);
    write_data(val);
}

static void isapnp_write_word(unsigned char idx, unsigned short val)
{
    isapnp_write_byte(idx, val >> 8);
    isapnp_write_byte(idx + 1, val);
}

static void isapnp_key(void)
{
    unsigned char code = 0x6a, msb;
    int i;

    mdelay(1);
    write_address(0x00);
    write_address(0x00);

    write_address(code);

    for (i = 1; i < 32; i++) {
        msb = ((code & 0x01) ^ ((code & 0x02) >> 1)) << 7;
        code = (code >> 1) | msb;
        write_address(code);
    }
}

/* place all pnp cards in wait-for-key state */
static void isapnp_wait(void)
{
    isapnp_write_byte(0x02, 0x02);
}

static void isapnp_wake(unsigned char csn)
{
    isapnp_write_byte(0x03, csn);
}

static void isapnp_device(unsigned char logdev)
{
    isapnp_write_byte(0x07, logdev);
}

static void isapnp_activate(unsigned char logdev)
{
    isapnp_device(logdev);
    isapnp_write_byte(ISAPNP_CFG_ACTIVATE, 1);
    udelay(250);
}

static void isapnp_deactivate(unsigned char logdev)
{
    isapnp_device(logdev);
    isapnp_write_byte(ISAPNP_CFG_ACTIVATE, 0);
    udelay(500);
}

static void __init isapnp_peek(unsigned char *data, int bytes)
{
    int i, j;
    unsigned char d = 0;

    for (i = 1; i <= bytes; i++) {
        for (j = 0; j < 20; j++) {
            d = isapnp_read_byte(0x05);
            if (d & 1)
                break;
            udelay(100);
        }
        if (!(d & 1)) {
            if (data != NULL)
                *data++ = 0xff;
            continue;
        }
        d = isapnp_read_byte(0x04); /* PRESDI */
        isapnp_checksum_value += d;
        if (data != NULL)
            *data++ = d;
    }
}

#define RDP_STEP    32  /* minimum is 4 */

static int isapnp_next_rdp(void)
{
    int rdp = isapnp_rdp;
    static int old_rdp = 0;

    if (old_rdp) {
        release_region(old_rdp, 1);
        old_rdp = 0;
    }
    while (rdp <= 0x3ff) {
        /*
         *      We cannot use NE2000 probe spaces for ISAPnP or we
         *      will lock up machines.
         */
        if ((rdp < 0x280 || rdp > 0x380)
            && request_region(rdp, 1, "ISAPnP")) {
            isapnp_rdp = rdp;
            old_rdp = rdp;
            return 0;
        }
        rdp += RDP_STEP;
    }
    return -1;
}

/* Set read port address */
static inline void isapnp_set_rdp(void)
{
    isapnp_write_byte(0x00, isapnp_rdp >> 2);
    udelay(100);
}

/*
 *  Perform an isolation. The port selection code now tries to avoid
 *  "dangerous to read" ports.
 */
static int __init isapnp_isolate_rdp_select(void)
{
    isapnp_wait();
    isapnp_key();

    /* Control: reset CSN and conditionally everything else too */
    isapnp_write_byte(0x02, isapnp_reset ? 0x05 : 0x04);
    mdelay(2);

    isapnp_wait();
    isapnp_key();
    isapnp_wake(0x00);

    if (isapnp_next_rdp() < 0) {
        isapnp_wait();
        return -1;
    }

    isapnp_set_rdp();
    udelay(1000);
    write_address(0x01);
    udelay(1000);
    return 0;
}

/*
 *  Isolate (assign uniqued CSN) to all ISA PnP devices.
 */
static int __init isapnp_isolate(void)
{
    unsigned char checksum = 0x6a;
    unsigned char chksum = 0x00;
    unsigned char bit = 0x00;
    int data;
    int csn = 0;
    int i;
    int iteration = 1;

    isapnp_rdp = 0x213;
    if (isapnp_isolate_rdp_select() < 0)
        return -1;

    while (1) {
        for (i = 1; i <= 64; i++) {
            data = read_data() << 8;
            udelay(250);
            data = data | read_data();
            udelay(250);
            if (data == 0x55aa)
                bit = 0x01;
            checksum =
                ((((checksum ^ (checksum >> 1)) & 0x01) ^ bit) << 7)
                | (checksum >> 1);
            bit = 0x00;
        }
        for (i = 65; i <= 72; i++) {
            data = read_data() << 8;
            udelay(250);
            data = data | read_data();
            udelay(250);
            if (data == 0x55aa)
                chksum |= (1 << (i - 65));
        }
        if (checksum != 0x00 && checksum == chksum) {
            csn++;

            isapnp_write_byte(0x06, csn);
            udelay(250);
            iteration++;
            isapnp_wake(0x00);
            isapnp_set_rdp();
            udelay(1000);
            write_address(0x01);
            udelay(1000);
            goto __next;
        }
        if (iteration == 1) {
            isapnp_rdp += RDP_STEP;
            if (isapnp_isolate_rdp_select() < 0)
                return -1;
        } else if (iteration > 1) {
            break;
        }
__next:
        if (csn == 255)
            break;
        checksum = 0x6a;
        chksum = 0x00;
        bit = 0x00;
    }
    isapnp_wait();
    isapnp_csn_count = csn;
    return csn;
}

/*
 *  Read one tag from stream.
 */
static int __init isapnp_read_tag(unsigned char *type, unsigned short *size)
{
    unsigned char tag, tmp[2];

    isapnp_peek(&tag, 1);
    if (tag == 0)       /* invalid tag */
        return -1;
    if (tag & 0x80) {   /* large item */
        *type = tag;
        isapnp_peek(tmp, 2);
        *size = (tmp[1] << 8) | tmp[0];
    } else {
        *type = (tag >> 3) & 0x0f;
        *size = tag & 0x07;
    }
#if 0
    printk(KERN_DEBUG "tag = 0x%x, type = 0x%x, size = %i\n", tag, *type,
           *size);
#endif
    if (*type == 0xff && *size == 0xffff)   /* probably invalid data */
        return -1;
    return 0;
}

/*
 *  Skip specified number of bytes from stream.
 */
static void __init isapnp_skip_bytes(int count)
{
    isapnp_peek(NULL, count);
}

/*
 *  Parse logical device tag.
 */
static struct pnp_dev *__init isapnp_parse_device(struct pnp_card *card,
                          int size, int number)
{
    unsigned char tmp[6];
    struct pnp_dev *dev;
    u32 eisa_id;
    char id[8];

    isapnp_peek(tmp, size);
    eisa_id = tmp[0] | tmp[1] << 8 | tmp[2] << 16 | tmp[3] << 24;
    pnp_eisa_id_to_string(eisa_id, id);

    dev = pnp_alloc_dev(&isapnp_protocol, number, id);
    if (!dev)
        return NULL;

    dev->card = card;
    dev->capabilities |= PNP_CONFIGURABLE;
    dev->capabilities |= PNP_READ;
    dev->capabilities |= PNP_WRITE;
    dev->capabilities |= PNP_DISABLE;
    pnp_init_resources(dev);
    return dev;
}

/*
 *  Add IRQ resource to resources list.
 */
static void __init isapnp_parse_irq_resource(struct pnp_dev *dev,
                         unsigned int option_flags,
                         int size)
{
    unsigned char tmp[3];
    unsigned long bits;
    pnp_irq_mask_t map;
    unsigned char flags = IORESOURCE_IRQ_HIGHEDGE;

    isapnp_peek(tmp, size);
    bits = (tmp[1] << 8) | tmp[0];

    bitmap_zero(map.bits, PNP_IRQ_NR);
    bitmap_copy(map.bits, &bits, 16);

    if (size > 2)
        flags = tmp[2];

    pnp_register_irq_resource(dev, option_flags, &map, flags);
}

/*
 *  Add DMA resource to resources list.
 */
static void __init isapnp_parse_dma_resource(struct pnp_dev *dev,
                         unsigned int option_flags,
                         int size)
{
    unsigned char tmp[2];

    isapnp_peek(tmp, size);
    pnp_register_dma_resource(dev, option_flags, tmp[0], tmp[1]);
}

/*
 *  Add port resource to resources list.
 */
static void __init isapnp_parse_port_resource(struct pnp_dev *dev,
                          unsigned int option_flags,
                          int size)
{
    unsigned char tmp[7];
    resource_size_t min, max, align, len;
    unsigned char flags;

    isapnp_peek(tmp, size);
    min = (tmp[2] << 8) | tmp[1];
    max = (tmp[4] << 8) | tmp[3];
    align = tmp[5];
    len = tmp[6];
    flags = tmp[0] ? IORESOURCE_IO_16BIT_ADDR : 0;
    pnp_register_port_resource(dev, option_flags,
                   min, max, align, len, flags);
}

/*
 *  Add fixed port resource to resources list.
 */
static void __init isapnp_parse_fixed_port_resource(struct pnp_dev *dev,
                            unsigned int option_flags,
                            int size)
{
    unsigned char tmp[3];
    resource_size_t base, len;

    isapnp_peek(tmp, size);
    base = (tmp[1] << 8) | tmp[0];
    len = tmp[2];
    pnp_register_port_resource(dev, option_flags, base, base, 0, len,
                   IORESOURCE_IO_FIXED);
}

/*
 *  Add memory resource to resources list.
 */
static void __init isapnp_parse_mem_resource(struct pnp_dev *dev,
                         unsigned int option_flags,
                         int size)
{
    unsigned char tmp[9];
    resource_size_t min, max, align, len;
    unsigned char flags;

    isapnp_peek(tmp, size);
    min = ((tmp[2] << 8) | tmp[1]) << 8;
    max = ((tmp[4] << 8) | tmp[3]) << 8;
    align = (tmp[6] << 8) | tmp[5];
    len = ((tmp[8] << 8) | tmp[7]) << 8;
    flags = tmp[0];
    pnp_register_mem_resource(dev, option_flags,
                  min, max, align, len, flags);
}

/*
 *  Add 32-bit memory resource to resources list.
 */
static void __init isapnp_parse_mem32_resource(struct pnp_dev *dev,
                           unsigned int option_flags,
                           int size)
{
    unsigned char tmp[17];
    resource_size_t min, max, align, len;
    unsigned char flags;

    isapnp_peek(tmp, size);
    min = (tmp[4] << 24) | (tmp[3] << 16) | (tmp[2] << 8) | tmp[1];
    max = (tmp[8] << 24) | (tmp[7] << 16) | (tmp[6] << 8) | tmp[5];
    align = (tmp[12] << 24) | (tmp[11] << 16) | (tmp[10] << 8) | tmp[9];
    len = (tmp[16] << 24) | (tmp[15] << 16) | (tmp[14] << 8) | tmp[13];
    flags = tmp[0];
    pnp_register_mem_resource(dev, option_flags,
                  min, max, align, len, flags);
}

/*
 *  Add 32-bit fixed memory resource to resources list.
 */
static void __init isapnp_parse_fixed_mem32_resource(struct pnp_dev *dev,
                             unsigned int option_flags,
                             int size)
{
    unsigned char tmp[9];
    resource_size_t base, len;
    unsigned char flags;

    isapnp_peek(tmp, size);
    base = (tmp[4] << 24) | (tmp[3] << 16) | (tmp[2] << 8) | tmp[1];
    len = (tmp[8] << 24) | (tmp[7] << 16) | (tmp[6] << 8) | tmp[5];
    flags = tmp[0];
    pnp_register_mem_resource(dev, option_flags, base, base, 0, len, flags);
}

/*
 *  Parse card name for ISA PnP device.
 */
static void __init
isapnp_parse_name(char *name, unsigned int name_max, unsigned short *size)
{
    if (name[0] == '\0') {
        unsigned short size1 =
            *size >= name_max ? (name_max - 1) : *size;
        isapnp_peek(name, size1);
        name[size1] = '\0';
        *size -= size1;

        /* clean whitespace from end of string */
        while (size1 > 0 && name[--size1] == ' ')
            name[size1] = '\0';
    }
}

/*
 *  Parse resource map for logical device.
 */
static int __init isapnp_create_device(struct pnp_card *card,
                       unsigned short size)
{
    int number = 0, skip = 0, priority, compat = 0;
    unsigned char type, tmp[17];
    unsigned int option_flags;
    struct pnp_dev *dev;
    u32 eisa_id;
    char id[8];

    if ((dev = isapnp_parse_device(card, size, number++)) == NULL)
        return 1;
    option_flags = 0;
    pnp_add_card_device(card, dev);

    while (1) {
        if (isapnp_read_tag(&type, &size) < 0)
            return 1;
        if (skip && type != _STAG_LOGDEVID && type != _STAG_END)
            goto __skip;
        switch (type) {
        case _STAG_LOGDEVID:
            if (size >= 5 && size <= 6) {
                if ((dev =
                     isapnp_parse_device(card, size,
                             number++)) == NULL)
                    return 1;
                size = 0;
                skip = 0;
                option_flags = 0;
                pnp_add_card_device(card, dev);
            } else {
                skip = 1;
            }
            compat = 0;
            break;
        case _STAG_COMPATDEVID:
            if (size == 4 && compat < DEVICE_COUNT_COMPATIBLE) {
                isapnp_peek(tmp, 4);
                eisa_id = tmp[0] | tmp[1] << 8 |
                      tmp[2] << 16 | tmp[3] << 24;
                pnp_eisa_id_to_string(eisa_id, id);
                pnp_add_id(dev, id);
                compat++;
                size = 0;
            }
            break;
        case _STAG_IRQ:
            if (size < 2 || size > 3)
                goto __skip;
            isapnp_parse_irq_resource(dev, option_flags, size);
            size = 0;
            break;
        case _STAG_DMA:
            if (size != 2)
                goto __skip;
            isapnp_parse_dma_resource(dev, option_flags, size);
            size = 0;
            break;
        case _STAG_STARTDEP:
            if (size > 1)
                goto __skip;
            priority = PNP_RES_PRIORITY_ACCEPTABLE;
            if (size > 0) {
                isapnp_peek(tmp, size);
                priority = tmp[0];
                size = 0;
            }
            option_flags = pnp_new_dependent_set(dev, priority);
            break;
        case _STAG_ENDDEP:
            if (size != 0)
                goto __skip;
            option_flags = 0;
            break;
        case _STAG_IOPORT:
            if (size != 7)
                goto __skip;
            isapnp_parse_port_resource(dev, option_flags, size);
            size = 0;
            break;
        case _STAG_FIXEDIO:
            if (size != 3)
                goto __skip;
            isapnp_parse_fixed_port_resource(dev, option_flags,
                             size);
            size = 0;
            break;
        case _STAG_VENDOR:
            break;
        case _LTAG_MEMRANGE:
            if (size != 9)
                goto __skip;
            isapnp_parse_mem_resource(dev, option_flags, size);
            size = 0;
            break;
        case _LTAG_ANSISTR:
            isapnp_parse_name(dev->name, sizeof(dev->name), &size);
            break;
        case _LTAG_UNICODESTR:
            /* silently ignore */
            /* who use unicode for hardware identification? */
            break;
        case _LTAG_VENDOR:
            break;
        case _LTAG_MEM32RANGE:
            if (size != 17)
                goto __skip;
            isapnp_parse_mem32_resource(dev, option_flags, size);
            size = 0;
            break;
        case _LTAG_FIXEDMEM32RANGE:
            if (size != 9)
                goto __skip;
            isapnp_parse_fixed_mem32_resource(dev, option_flags,
                              size);
            size = 0;
            break;
        case _STAG_END:
            if (size > 0)
                isapnp_skip_bytes(size);
            return 1;
        default:
            dev_err(&dev->dev, "unknown tag %#x (card %i), "
                "ignored\n", type, card->number);
        }
__skip:
        if (size > 0)
            isapnp_skip_bytes(size);
    }
    return 0;
}

/*
 *  Parse resource map for ISA PnP card.
 */
static void __init isapnp_parse_resource_map(struct pnp_card *card)
{
    unsigned char type, tmp[17];
    unsigned short size;

    while (1) {
        if (isapnp_read_tag(&type, &size) < 0)
            return;
        switch (type) {
        case _STAG_PNPVERNO:
            if (size != 2)
                goto __skip;
            isapnp_peek(tmp, 2);
            card->pnpver = tmp[0];
            card->productver = tmp[1];
            size = 0;
            break;
        case _STAG_LOGDEVID:
            if (size >= 5 && size <= 6) {
                if (isapnp_create_device(card, size) == 1)
                    return;
                size = 0;
            }
            break;
        case _STAG_VENDOR:
            break;
        case _LTAG_ANSISTR:
            isapnp_parse_name(card->name, sizeof(card->name),
                      &size);
            break;
        case _LTAG_UNICODESTR:
            /* silently ignore */
            /* who use unicode for hardware identification? */
            break;
        case _LTAG_VENDOR:
            break;
        case _STAG_END:
            if (size > 0)
                isapnp_skip_bytes(size);
            return;
        default:
            dev_err(&card->dev, "unknown tag %#x, ignored\n",
                   type);
        }
__skip:
        if (size > 0)
            isapnp_skip_bytes(size);
    }
}

/*
 *  Compute ISA PnP checksum for first eight bytes.
 */
static unsigned char __init isapnp_checksum(unsigned char *data)
{
    int i, j;
    unsigned char checksum = 0x6a, bit, b;

    for (i = 0; i < 8; i++) {
        b = data[i];
        for (j = 0; j < 8; j++) {
            bit = 0;
            if (b & (1 << j))
                bit = 1;
            checksum =
                ((((checksum ^ (checksum >> 1)) & 0x01) ^ bit) << 7)
                | (checksum >> 1);
        }
    }
    return checksum;
}

/*
 *  Build device list for all present ISA PnP devices.
 */
static int __init isapnp_build_device_list(void)
{
    int csn;
    unsigned char header[9], checksum;
    struct pnp_card *card;
    u32 eisa_id;
    char id[8];

    isapnp_wait();
    isapnp_key();
    for (csn = 1; csn <= isapnp_csn_count; csn++) {
        isapnp_wake(csn);
        isapnp_peek(header, 9);
        checksum = isapnp_checksum(header);
        eisa_id = header[0] | header[1] << 8 |
              header[2] << 16 | header[3] << 24;
        pnp_eisa_id_to_string(eisa_id, id);
        card = pnp_alloc_card(&isapnp_protocol, csn, id);
        if (!card)
            continue;

#if 0
        dev_info(&card->dev,
               "vendor: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
               header[0], header[1], header[2], header[3], header[4],
               header[5], header[6], header[7], header[8]);
        dev_info(&card->dev, "checksum = %#x\n", checksum);
#endif
        INIT_LIST_HEAD(&card->devices);
        card->serial =
            (header[7] << 24) | (header[6] << 16) | (header[5] << 8) |
            header[4];
        isapnp_checksum_value = 0x00;
        isapnp_parse_resource_map(card);
        if (isapnp_checksum_value != 0x00)
            dev_err(&card->dev, "invalid checksum %#x\n",
                isapnp_checksum_value);
        card->checksum = isapnp_checksum_value;

        pnp_add_card(card);
    }
    isapnp_wait();
    return 0;
}

/*
 *  Basic configuration routines.
 */

int isapnp_present(void)
{
    struct pnp_card *card;

    pnp_for_each_card(card) {
        if (card->protocol == &isapnp_protocol)
            return 1;
    }
    return 0;
}

int isapnp_cfg_begin(int csn, int logdev)
{
    if (csn < 1 || csn > isapnp_csn_count || logdev > 10)
        return -EINVAL;
    mutex_lock(&isapnp_cfg_mutex);
    isapnp_wait();
    isapnp_key();
    isapnp_wake(csn);
#if 0
    /* to avoid malfunction when the isapnptools package is used */
    /* we must set RDP to our value again */
    /* it is possible to set RDP only in the isolation phase */
    /*   Jens Thoms Toerring <[email protected]> */
    isapnp_write_byte(0x02, 0x04);  /* clear CSN of card */
    mdelay(2);      /* is this necessary? */
    isapnp_wake(csn);   /* bring card into sleep state */
    isapnp_wake(0);     /* bring card into isolation state */
    isapnp_set_rdp();   /* reset the RDP port */
    udelay(1000);       /* delay 1000us */
    isapnp_write_byte(0x06, csn);   /* reset CSN to previous value */
    udelay(250);        /* is this necessary? */
#endif
    if (logdev >= 0)
        isapnp_device(logdev);
    return 0;
}

int isapnp_cfg_end(void)
{
    isapnp_wait();
    mutex_unlock(&isapnp_cfg_mutex);
    return 0;
}

/*
 *  Initialization.
 */

EXPORT_SYMBOL(isapnp_protocol);
EXPORT_SYMBOL(isapnp_present);
EXPORT_SYMBOL(isapnp_cfg_begin);
EXPORT_SYMBOL(isapnp_cfg_end);
EXPORT_SYMBOL(isapnp_write_byte);

static int isapnp_get_resources(struct pnp_dev *dev)
{
    int i, ret;

    pnp_dbg(&dev->dev, "get resources\n");
    pnp_init_resources(dev);
    isapnp_cfg_begin(dev->card->number, dev->number);
    dev->active = isapnp_read_byte(ISAPNP_CFG_ACTIVATE);
    if (!dev->active)
        goto __end;

    for (i = 0; i < ISAPNP_MAX_PORT; i++) {
        ret = isapnp_read_word(ISAPNP_CFG_PORT + (i << 1));
        pnp_add_io_resource(dev, ret, ret,
                    ret == 0 ? IORESOURCE_DISABLED : 0);
    }
    for (i = 0; i < ISAPNP_MAX_MEM; i++) {
        ret = isapnp_read_word(ISAPNP_CFG_MEM + (i << 3)) << 8;
        pnp_add_mem_resource(dev, ret, ret,
                     ret == 0 ? IORESOURCE_DISABLED : 0);
    }
    for (i = 0; i < ISAPNP_MAX_IRQ; i++) {
        ret = isapnp_read_word(ISAPNP_CFG_IRQ + (i << 1)) >> 8;
        pnp_add_irq_resource(dev, ret,
                     ret == 0 ? IORESOURCE_DISABLED : 0);
    }
    for (i = 0; i < ISAPNP_MAX_DMA; i++) {
        ret = isapnp_read_byte(ISAPNP_CFG_DMA + i);
        pnp_add_dma_resource(dev, ret,
                     ret == 4 ? IORESOURCE_DISABLED : 0);
    }

__end:
    isapnp_cfg_end();
    return 0;
}

static int isapnp_set_resources(struct pnp_dev *dev)
{
    struct resource *res;
    int tmp;

    pnp_dbg(&dev->dev, "set resources\n");
    isapnp_cfg_begin(dev->card->number, dev->number);
    dev->active = 1;
    for (tmp = 0; tmp < ISAPNP_MAX_PORT; tmp++) {
        res = pnp_get_resource(dev, IORESOURCE_IO, tmp);
        if (pnp_resource_enabled(res)) {
            pnp_dbg(&dev->dev, "  set io  %d to %#llx\n",
                tmp, (unsigned long long) res->start);
            isapnp_write_word(ISAPNP_CFG_PORT + (tmp << 1),
                      res->start);
        }
    }
    for (tmp = 0; tmp < ISAPNP_MAX_IRQ; tmp++) {
        res = pnp_get_resource(dev, IORESOURCE_IRQ, tmp);
        if (pnp_resource_enabled(res)) {
            int irq = res->start;
            if (irq == 2)
                irq = 9;
            pnp_dbg(&dev->dev, "  set irq %d to %d\n", tmp, irq);
            isapnp_write_byte(ISAPNP_CFG_IRQ + (tmp << 1), irq);
        }
    }
    for (tmp = 0; tmp < ISAPNP_MAX_DMA; tmp++) {
        res = pnp_get_resource(dev, IORESOURCE_DMA, tmp);
        if (pnp_resource_enabled(res)) {
            pnp_dbg(&dev->dev, "  set dma %d to %lld\n",
                tmp, (unsigned long long) res->start);
            isapnp_write_byte(ISAPNP_CFG_DMA + tmp, res->start);
        }
    }
    for (tmp = 0; tmp < ISAPNP_MAX_MEM; tmp++) {
        res = pnp_get_resource(dev, IORESOURCE_MEM, tmp);
        if (pnp_resource_enabled(res)) {
            pnp_dbg(&dev->dev, "  set mem %d to %#llx\n",
                tmp, (unsigned long long) res->start);
            isapnp_write_word(ISAPNP_CFG_MEM + (tmp << 3),
                      (res->start >> 8) & 0xffff);
        }
    }
    /* FIXME: We aren't handling 32bit mems properly here */
    isapnp_activate(dev->number);
    isapnp_cfg_end();
    return 0;
}

static int isapnp_disable_resources(struct pnp_dev *dev)
{
    if (!dev->active)
        return -EINVAL;
    isapnp_cfg_begin(dev->card->number, dev->number);
    isapnp_deactivate(dev->number);
    dev->active = 0;
    isapnp_cfg_end();
    return 0;
}

struct pnp_protocol isapnp_protocol = {
    .name = "ISA Plug and Play",
    .get = isapnp_get_resources,
    .set = isapnp_set_resources,
    .disable = isapnp_disable_resources,
};

static int __init isapnp_init(void)
{
    int cards;
    struct pnp_card *card;
    struct pnp_dev *dev;

    if (isapnp_disable) {
        printk(KERN_INFO "isapnp: ISA Plug & Play support disabled\n");
        return 0;
    }
#ifdef CONFIG_PPC
    if (check_legacy_ioport(_PIDXR) || check_legacy_ioport(_PNPWRP))
        return -EINVAL;
#endif
#ifdef ISAPNP_REGION_OK
    if (!request_region(_PIDXR, 1, "isapnp index")) {
        printk(KERN_ERR "isapnp: Index Register 0x%x already used\n",
               _PIDXR);
        return -EBUSY;
    }
#endif
    if (!request_region(_PNPWRP, 1, "isapnp write")) {
        printk(KERN_ERR
               "isapnp: Write Data Register 0x%x already used\n",
               _PNPWRP);
#ifdef ISAPNP_REGION_OK
        release_region(_PIDXR, 1);
#endif
        return -EBUSY;
    }

    if (pnp_register_protocol(&isapnp_protocol) < 0)
        return -EBUSY;

    /*
     *      Print a message. The existing ISAPnP code is hanging machines
     *      so let the user know where.
     */

    printk(KERN_INFO "isapnp: Scanning for PnP cards...\n");
    if (isapnp_rdp >= 0x203 && isapnp_rdp <= 0x3ff) {
        isapnp_rdp |= 3;
        if (!request_region(isapnp_rdp, 1, "isapnp read")) {
            printk(KERN_ERR
                   "isapnp: Read Data Register 0x%x already used\n",
                   isapnp_rdp);
#ifdef ISAPNP_REGION_OK
            release_region(_PIDXR, 1);
#endif
            release_region(_PNPWRP, 1);
            return -EBUSY;
        }
        isapnp_set_rdp();
    }
    if (isapnp_rdp < 0x203 || isapnp_rdp > 0x3ff) {
        cards = isapnp_isolate();
        if (cards < 0 || (isapnp_rdp < 0x203 || isapnp_rdp > 0x3ff)) {
#ifdef ISAPNP_REGION_OK
            release_region(_PIDXR, 1);
#endif
            release_region(_PNPWRP, 1);
            printk(KERN_INFO
                   "isapnp: No Plug & Play device found\n");
            return 0;
        }
        request_region(isapnp_rdp, 1, "isapnp read");
    }
    isapnp_build_device_list();
    cards = 0;

    protocol_for_each_card(&isapnp_protocol, card) {
        cards++;
        if (isapnp_verbose) {
            dev_info(&card->dev, "card '%s'\n",
                   card->name[0] ? card->name : "unknown");
            if (isapnp_verbose < 2)
                continue;
            card_for_each_dev(card, dev) {
                dev_info(&card->dev, "device '%s'\n",
                       dev->name[0] ? dev->name : "unknown");
            }
        }
    }
    if (cards)
        printk(KERN_INFO
               "isapnp: %i Plug & Play card%s detected total\n", cards,
               cards > 1 ? "s" : "");
    else
        printk(KERN_INFO "isapnp: No Plug & Play card found\n");

    isapnp_proc_init();
    return 0;
}

device_initcall(isapnp_init);

/* format is: noisapnp */

static int __init isapnp_setup_disable(char *str)
{
    isapnp_disable = 1;
    return 1;
}

__setup("noisapnp", isapnp_setup_disable);

/* format is: isapnp=rdp,reset,skip_pci_scan,verbose */

static int __init isapnp_setup_isapnp(char *str)
{
    (void)((get_option(&str, &isapnp_rdp) == 2) &&
           (get_option(&str, &isapnp_reset) == 2) &&
           (get_option(&str, &isapnp_verbose) == 2));
    return 1;
}

__setup("isapnp=", isapnp_setup_isapnp);