proc: fix NULL ->i_fop oops

[wrt350n-kernel.git] / drivers / ide / setup-pci.c

/*
 *  linux/drivers/ide/setup-pci.c               Version 1.10    2002/08/19
 *
 *  Copyright (c) 1998-2000  Andre Hedrick <andre@linux-ide.org>
 *
 *  Copyright (c) 1995-1998  Mark Lord
 *  May be copied or modified under the terms of the GNU General Public License
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/ide.h>
#include <linux/dma-mapping.h>

#include <asm/io.h>
#include <asm/irq.h>


/**
 *      ide_match_hwif  -       match a PCI IDE against an ide_hwif
 *      @io_base: I/O base of device
 *      @bootable: set if its bootable
 *      @name: name of device
 *
 *      Match a PCI IDE port against an entry in ide_hwifs[],
 *      based on io_base port if possible. Return the matching hwif,
 *      or a new hwif. If we find an error (clashing, out of devices, etc)
 *      return NULL
 *
 *      FIXME: we need to handle mmio matches here too
 */

static ide_hwif_t *ide_match_hwif(unsigned long io_base, u8 bootable, const char *name)
{
        int h;
        ide_hwif_t *hwif;

        /*
         * Look for a hwif with matching io_base specified using
         * parameters to ide_setup().
         */
        for (h = 0; h < MAX_HWIFS; ++h) {
                hwif = &ide_hwifs[h];
                if (hwif->io_ports[IDE_DATA_OFFSET] == io_base) {
                        if (hwif->chipset == ide_forced)
                                return hwif; /* a perfect match */
                }
        }
        /*
         * Look for a hwif with matching io_base default value.
         * If chipset is "ide_unknown", then claim that hwif slot.
         * Otherwise, some other chipset has already claimed it..  :(
         */
        for (h = 0; h < MAX_HWIFS; ++h) {
                hwif = &ide_hwifs[h];
                if (hwif->io_ports[IDE_DATA_OFFSET] == io_base) {
                        if (hwif->chipset == ide_unknown)
                                return hwif; /* match */
                        printk(KERN_ERR "%s: port 0x%04lx already claimed by %s\n",
                                name, io_base, hwif->name);
                        return NULL;    /* already claimed */
                }
        }
        /*
         * Okay, there is no hwif matching our io_base,
         * so we'll just claim an unassigned slot.
         * Give preference to claiming other slots before claiming ide0/ide1,
         * just in case there's another interface yet-to-be-scanned
         * which uses ports 1f0/170 (the ide0/ide1 defaults).
         *
         * Unless there is a bootable card that does not use the standard
         * ports 1f0/170 (the ide0/ide1 defaults). The (bootable) flag.
         */
        if (bootable) {
                for (h = 0; h < MAX_HWIFS; ++h) {
                        hwif = &ide_hwifs[h];
                        if (hwif->chipset == ide_unknown)
                                return hwif;    /* pick an unused entry */
                }
        } else {
                for (h = 2; h < MAX_HWIFS; ++h) {
                        hwif = ide_hwifs + h;
                        if (hwif->chipset == ide_unknown)
                                return hwif;    /* pick an unused entry */
                }
        }
        for (h = 0; h < 2 && h < MAX_HWIFS; ++h) {
                hwif = ide_hwifs + h;
                if (hwif->chipset == ide_unknown)
                        return hwif;    /* pick an unused entry */
        }
        printk(KERN_ERR "%s: too many IDE interfaces, no room in table\n", name);
        return NULL;
}

/**
 *      ide_setup_pci_baseregs  -       place a PCI IDE controller native
 *      @dev: PCI device of interface to switch native
 *      @name: Name of interface
 *
 *      We attempt to place the PCI interface into PCI native mode. If
 *      we succeed the BARs are ok and the controller is in PCI mode.
 *      Returns 0 on success or an errno code. 
 *
 *      FIXME: if we program the interface and then fail to set the BARS
 *      we don't switch it back to legacy mode. Do we actually care ??
 */
 
static int ide_setup_pci_baseregs (struct pci_dev *dev, const char *name)
{
        u8 progif = 0;

        /*
         * Place both IDE interfaces into PCI "native" mode:
         */
        if (pci_read_config_byte(dev, PCI_CLASS_PROG, &progif) ||
                         (progif & 5) != 5) {
                if ((progif & 0xa) != 0xa) {
                        printk(KERN_INFO "%s: device not capable of full "
                                "native PCI mode\n", name);
                        return -EOPNOTSUPP;
                }
                printk("%s: placing both ports into native PCI mode\n", name);
                (void) pci_write_config_byte(dev, PCI_CLASS_PROG, progif|5);
                if (pci_read_config_byte(dev, PCI_CLASS_PROG, &progif) ||
                    (progif & 5) != 5) {
                        printk(KERN_ERR "%s: rewrite of PROGIF failed, wanted "
                                "0x%04x, got 0x%04x\n",
                                name, progif|5, progif);
                        return -EOPNOTSUPP;
                }
        }
        return 0;
}

#ifdef CONFIG_BLK_DEV_IDEDMA_PCI
/**
 *      ide_get_or_set_dma_base         -       setup BMIBA
 *      @d: IDE port info
 *      @hwif: IDE interface
 *
 *      Fetch the DMA Bus-Master-I/O-Base-Address (BMIBA) from PCI space.
 *      Where a device has a partner that is already in DMA mode we check
 *      and enforce IDE simplex rules.
 */

static unsigned long ide_get_or_set_dma_base(const struct ide_port_info *d, ide_hwif_t *hwif)
{
        unsigned long   dma_base = 0;
        struct pci_dev  *dev = hwif->pci_dev;

        if (hwif->mmio)
                return hwif->dma_base;

        if (hwif->mate && hwif->mate->dma_base) {
                dma_base = hwif->mate->dma_base - (hwif->channel ? 0 : 8);
        } else {
                u8 baridx = (d->host_flags & IDE_HFLAG_CS5520) ? 2 : 4;

                dma_base = pci_resource_start(dev, baridx);

                if (dma_base == 0)
                        printk(KERN_ERR "%s: DMA base is invalid\n", d->name);
        }

        if ((d->host_flags & IDE_HFLAG_CS5520) == 0 && dma_base) {
                u8 simplex_stat = 0;
                dma_base += hwif->channel ? 8 : 0;

                switch(dev->device) {
                        case PCI_DEVICE_ID_AL_M5219:
                        case PCI_DEVICE_ID_AL_M5229:
                        case PCI_DEVICE_ID_AMD_VIPER_7409:
                        case PCI_DEVICE_ID_CMD_643:
                        case PCI_DEVICE_ID_SERVERWORKS_CSB5IDE:
                        case PCI_DEVICE_ID_REVOLUTION:
                                simplex_stat = inb(dma_base + 2);
                                outb(simplex_stat & 0x60, dma_base + 2);
                                simplex_stat = inb(dma_base + 2);
                                if (simplex_stat & 0x80) {
                                        printk(KERN_INFO "%s: simplex device: "
                                                         "DMA forced\n",
                                                         d->name);
                                }
                                break;
                        default:
                                /*
                                 * If the device claims "simplex" DMA,
                                 * this means only one of the two interfaces
                                 * can be trusted with DMA at any point in time.
                                 * So we should enable DMA only on one of the
                                 * two interfaces.
                                 */
                                simplex_stat = hwif->INB(dma_base + 2);
                                if (simplex_stat & 0x80) {
                                        /* simplex device? */
/*
 *      At this point we haven't probed the drives so we can't make the
 *      appropriate decision. Really we should defer this problem
 *      until we tune the drive then try to grab DMA ownership if we want
 *      to be the DMA end. This has to be become dynamic to handle hot
 *      plug.
 */
                                        if (hwif->mate && hwif->mate->dma_base) {
                                                printk(KERN_INFO "%s: simplex device: "
                                                                 "DMA disabled\n",
                                                                 d->name);
                                                dma_base = 0;
                                        }
                                }
                }
        }
        return dma_base;
}
#endif /* CONFIG_BLK_DEV_IDEDMA_PCI */

void ide_setup_pci_noise(struct pci_dev *dev, const struct ide_port_info *d)
{
        printk(KERN_INFO "%s: IDE controller (0x%04x:0x%04x rev 0x%02x) at "
                         " PCI slot %s\n", d->name, dev->vendor, dev->device,
                         dev->revision, pci_name(dev));
}

EXPORT_SYMBOL_GPL(ide_setup_pci_noise);


/**
 *      ide_pci_enable  -       do PCI enables
 *      @dev: PCI device
 *      @d: IDE port info
 *
 *      Enable the IDE PCI device. We attempt to enable the device in full
 *      but if that fails then we only need BAR4 so we will enable that.
 *      
 *      Returns zero on success or an error code
 */

static int ide_pci_enable(struct pci_dev *dev, const struct ide_port_info *d)
{
        int ret;

        if (pci_enable_device(dev)) {
                ret = pci_enable_device_bars(dev, 1 << 4);
                if (ret < 0) {
                        printk(KERN_WARNING "%s: (ide_setup_pci_device:) "
                                "Could not enable device.\n", d->name);
                        goto out;
                }
                printk(KERN_WARNING "%s: BIOS configuration fixed.\n", d->name);
        }

        /*
         * assume all devices can do 32-bit DMA for now, we can add
         * a DMA mask field to the struct ide_port_info if we need it
         * (or let lower level driver set the DMA mask)
         */
        ret = pci_set_dma_mask(dev, DMA_32BIT_MASK);
        if (ret < 0) {
                printk(KERN_ERR "%s: can't set dma mask\n", d->name);
                goto out;
        }

        /* FIXME: Temporary - until we put in the hotplug interface logic
           Check that the bits we want are not in use by someone else. */
        ret = pci_request_region(dev, 4, "ide_tmp");
        if (ret < 0)
                goto out;

        pci_release_region(dev, 4);
out:
        return ret;
}

/**
 *      ide_pci_configure       -       configure an unconfigured device
 *      @dev: PCI device
 *      @d: IDE port info
 *
 *      Enable and configure the PCI device we have been passed.
 *      Returns zero on success or an error code.
 */

static int ide_pci_configure(struct pci_dev *dev, const struct ide_port_info *d)
{
        u16 pcicmd = 0;
        /*
         * PnP BIOS was *supposed* to have setup this device, but we
         * can do it ourselves, so long as the BIOS has assigned an IRQ
         * (or possibly the device is using a "legacy header" for IRQs).
         * Maybe the user deliberately *disabled* the device,
         * but we'll eventually ignore it again if no drives respond.
         */
        if (ide_setup_pci_baseregs(dev, d->name) || pci_write_config_word(dev, PCI_COMMAND, pcicmd|PCI_COMMAND_IO)) 
        {
                printk(KERN_INFO "%s: device disabled (BIOS)\n", d->name);
                return -ENODEV;
        }
        if (pci_read_config_word(dev, PCI_COMMAND, &pcicmd)) {
                printk(KERN_ERR "%s: error accessing PCI regs\n", d->name);
                return -EIO;
        }
        if (!(pcicmd & PCI_COMMAND_IO)) {
                printk(KERN_ERR "%s: unable to enable IDE controller\n", d->name);
                return -ENXIO;
        }
        return 0;
}

/**
 *      ide_pci_check_iomem     -       check a register is I/O
 *      @dev: PCI device
 *      @d: IDE port info
 *      @bar: BAR number
 *
 *      Checks if a BAR is configured and points to MMIO space. If so
 *      print an error and return an error code. Otherwise return 0
 */

static int ide_pci_check_iomem(struct pci_dev *dev, const struct ide_port_info *d, int bar)
{
        ulong flags = pci_resource_flags(dev, bar);
        
        /* Unconfigured ? */
        if (!flags || pci_resource_len(dev, bar) == 0)
                return 0;

        /* I/O space */         
        if(flags & PCI_BASE_ADDRESS_IO_MASK)
                return 0;
                
        /* Bad */
        printk(KERN_ERR "%s: IO baseregs (BIOS) are reported "
                        "as MEM, report to "
                        "<andre@linux-ide.org>.\n", d->name);
        return -EINVAL;
}

/**
 *      ide_hwif_configure      -       configure an IDE interface
 *      @dev: PCI device holding interface
 *      @d: IDE port info
 *      @mate: Paired interface if any
 *
 *      Perform the initial set up for the hardware interface structure. This
 *      is done per interface port rather than per PCI device. There may be
 *      more than one port per device.
 *
 *      Returns the new hardware interface structure, or NULL on a failure
 */

static ide_hwif_t *ide_hwif_configure(struct pci_dev *dev, const struct ide_port_info *d, ide_hwif_t *mate, int port, int irq)
{
        unsigned long ctl = 0, base = 0;
        ide_hwif_t *hwif;
        u8 bootable = (d->host_flags & IDE_HFLAG_BOOTABLE) ? 1 : 0;

        if ((d->host_flags & IDE_HFLAG_ISA_PORTS) == 0) {
                /*  Possibly we should fail if these checks report true */
                ide_pci_check_iomem(dev, d, 2*port);
                ide_pci_check_iomem(dev, d, 2*port+1);
 
                ctl  = pci_resource_start(dev, 2*port+1);
                base = pci_resource_start(dev, 2*port);
                if ((ctl && !base) || (base && !ctl)) {
                        printk(KERN_ERR "%s: inconsistent baseregs (BIOS) "
                                "for port %d, skipping\n", d->name, port);
                        return NULL;
                }
        }
        if (!ctl)
        {
                /* Use default values */
                ctl = port ? 0x374 : 0x3f4;
                base = port ? 0x170 : 0x1f0;
        }
        if ((hwif = ide_match_hwif(base, bootable, d->name)) == NULL)
                return NULL;    /* no room in ide_hwifs[] */
        if (hwif->io_ports[IDE_DATA_OFFSET] != base ||
            hwif->io_ports[IDE_CONTROL_OFFSET] != (ctl | 2)) {
                hw_regs_t hw;

                memset(&hw, 0, sizeof(hw));
#ifndef CONFIG_IDE_ARCH_OBSOLETE_INIT
                ide_std_init_ports(&hw, base, ctl | 2);
#else
                ide_init_hwif_ports(&hw, base, ctl | 2, NULL);
#endif
                memcpy(hwif->io_ports, hw.io_ports, sizeof(hwif->io_ports));
                hwif->noprobe = !hwif->io_ports[IDE_DATA_OFFSET];
        }
        hwif->chipset = d->chipset ? d->chipset : ide_pci;
        hwif->pci_dev = dev;
        hwif->cds = d;
        hwif->channel = port;

        if (!hwif->irq)
                hwif->irq = irq;
        if (mate) {
                hwif->mate = mate;
                mate->mate = hwif;
        }
        return hwif;
}

/**
 *      ide_hwif_setup_dma      -       configure DMA interface
 *      @dev: PCI device
 *      @d: IDE port info
 *      @hwif: IDE interface
 *
 *      Set up the DMA base for the interface. Enable the master bits as
 *      necessary and attempt to bring the device DMA into a ready to use
 *      state
 */

static void ide_hwif_setup_dma(struct pci_dev *dev, const struct ide_port_info *d, ide_hwif_t *hwif)
{
#ifdef CONFIG_BLK_DEV_IDEDMA_PCI
        u16 pcicmd;

        pci_read_config_word(dev, PCI_COMMAND, &pcicmd);

        if ((d->host_flags & IDE_HFLAG_NO_AUTODMA) == 0 ||
            ((dev->class >> 8) == PCI_CLASS_STORAGE_IDE &&
             (dev->class & 0x80))) {
                unsigned long dma_base = ide_get_or_set_dma_base(d, hwif);
                if (dma_base && !(pcicmd & PCI_COMMAND_MASTER)) {
                        /*
                         * Set up BM-DMA capability
                         * (PnP BIOS should have done this)
                         */
                        pci_set_master(dev);
                        if (pci_read_config_word(dev, PCI_COMMAND, &pcicmd) || !(pcicmd & PCI_COMMAND_MASTER)) {
                                printk(KERN_ERR "%s: %s error updating PCICMD\n",
                                        hwif->name, d->name);
                                dma_base = 0;
                        }
                }
                if (dma_base) {
                        if (d->init_dma) {
                                d->init_dma(hwif, dma_base);
                        } else {
                                ide_setup_dma(hwif, dma_base, 8);
                        }
                } else {
                        printk(KERN_INFO "%s: %s Bus-Master DMA disabled "
                                "(BIOS)\n", hwif->name, d->name);
                }
        }
#endif /* CONFIG_BLK_DEV_IDEDMA_PCI*/
}

/**
 *      ide_setup_pci_controller        -       set up IDE PCI
 *      @dev: PCI device
 *      @d: IDE port info
 *      @noisy: verbose flag
 *      @config: returned as 1 if we configured the hardware
 *
 *      Set up the PCI and controller side of the IDE interface. This brings
 *      up the PCI side of the device, checks that the device is enabled
 *      and enables it if need be
 */

static int ide_setup_pci_controller(struct pci_dev *dev, const struct ide_port_info *d, int noisy, int *config)
{
        int ret;
        u16 pcicmd;

        if (noisy)
                ide_setup_pci_noise(dev, d);

        ret = ide_pci_enable(dev, d);
        if (ret < 0)
                goto out;

        ret = pci_read_config_word(dev, PCI_COMMAND, &pcicmd);
        if (ret < 0) {
                printk(KERN_ERR "%s: error accessing PCI regs\n", d->name);
                goto out;
        }
        if (!(pcicmd & PCI_COMMAND_IO)) {       /* is device disabled? */
                ret = ide_pci_configure(dev, d);
                if (ret < 0)
                        goto out;
                *config = 1;
                printk(KERN_INFO "%s: device enabled (Linux)\n", d->name);
        }

out:
        return ret;
}

/**
 *      ide_pci_setup_ports     -       configure ports/devices on PCI IDE
 *      @dev: PCI device
 *      @d: IDE port info
 *      @pciirq: IRQ line
 *      @idx: ATA index table to update
 *
 *      Scan the interfaces attached to this device and do any
 *      necessary per port setup. Attach the devices and ask the
 *      generic DMA layer to do its work for us.
 *
 *      Normally called automaticall from do_ide_pci_setup_device,
 *      but is also used directly as a helper function by some controllers
 *      where the chipset setup is not the default PCI IDE one.
 */

void ide_pci_setup_ports(struct pci_dev *dev, const struct ide_port_info *d, int pciirq, u8 *idx)
{
        int channels = (d->host_flags & IDE_HFLAG_SINGLE) ? 1 : 2, port;
        ide_hwif_t *hwif, *mate = NULL;
        u8 tmp;

        /*
         * Set up the IDE ports
         */

        for (port = 0; port < channels; ++port) {
                const ide_pci_enablebit_t *e = &(d->enablebits[port]);

                if (e->reg && (pci_read_config_byte(dev, e->reg, &tmp) ||
                    (tmp & e->mask) != e->val)) {
                        printk(KERN_INFO "%s: IDE port disabled\n", d->name);
                        continue;       /* port not enabled */
                }

                if ((hwif = ide_hwif_configure(dev, d, mate, port, pciirq)) == NULL)
                        continue;

                /* setup proper ancestral information */
                hwif->gendev.parent = &dev->dev;

                *(idx + port) = hwif->index;

                
                if (d->init_iops)
                        d->init_iops(hwif);

                if ((d->host_flags & IDE_HFLAG_NO_DMA) == 0)
                        ide_hwif_setup_dma(dev, d, hwif);

                if ((!hwif->irq && (d->host_flags & IDE_HFLAG_LEGACY_IRQS)) ||
                    (d->host_flags & IDE_HFLAG_FORCE_LEGACY_IRQS))
                        hwif->irq = port ? 15 : 14;

                hwif->fixup = d->fixup;

                hwif->host_flags = d->host_flags;
                hwif->pio_mask = d->pio_mask;

                if ((d->host_flags & IDE_HFLAG_SERIALIZE) && hwif->mate)
                        hwif->mate->serialized = hwif->serialized = 1;

                if (d->host_flags & IDE_HFLAG_IO_32BIT) {
                        hwif->drives[0].io_32bit = 1;
                        hwif->drives[1].io_32bit = 1;
                }

                if (d->host_flags & IDE_HFLAG_UNMASK_IRQS) {
                        hwif->drives[0].unmask = 1;
                        hwif->drives[1].unmask = 1;
                }

                if (hwif->dma_base) {
                        hwif->swdma_mask = d->swdma_mask;
                        hwif->mwdma_mask = d->mwdma_mask;
                        hwif->ultra_mask = d->udma_mask;
                }

                hwif->drives[0].autotune = 1;
                hwif->drives[1].autotune = 1;

                if (d->host_flags & IDE_HFLAG_RQSIZE_256)
                        hwif->rqsize = 256;

                if (d->init_hwif)
                        /* Call chipset-specific routine
                         * for each enabled hwif
                         */
                        d->init_hwif(hwif);

                mate = hwif;
        }
}

EXPORT_SYMBOL_GPL(ide_pci_setup_ports);

/*
 * ide_setup_pci_device() looks at the primary/secondary interfaces
 * on a PCI IDE device and, if they are enabled, prepares the IDE driver
 * for use with them.  This generic code works for most PCI chipsets.
 *
 * One thing that is not standardized is the location of the
 * primary/secondary interface "enable/disable" bits.  For chipsets that
 * we "know" about, this information is in the struct ide_port_info;
 * for all other chipsets, we just assume both interfaces are enabled.
 */
static int do_ide_setup_pci_device(struct pci_dev *dev,
                                   const struct ide_port_info *d,
                                   u8 *idx, u8 noisy)
{
        int tried_config = 0;
        int pciirq, ret;

        ret = ide_setup_pci_controller(dev, d, noisy, &tried_config);
        if (ret < 0)
                goto out;

        /*
         * Can we trust the reported IRQ?
         */
        pciirq = dev->irq;

        /* Is it an "IDE storage" device in non-PCI mode? */
        if ((dev->class >> 8) == PCI_CLASS_STORAGE_IDE && (dev->class & 5) != 5) {
                if (noisy)
                        printk(KERN_INFO "%s: not 100%% native mode: "
                                "will probe irqs later\n", d->name);
                /*
                 * This allows offboard ide-pci cards the enable a BIOS,
                 * verify interrupt settings of split-mirror pci-config
                 * space, place chipset into init-mode, and/or preserve
                 * an interrupt if the card is not native ide support.
                 */
                ret = d->init_chipset ? d->init_chipset(dev, d->name) : 0;
                if (ret < 0)
                        goto out;
                pciirq = ret;
        } else if (tried_config) {
                if (noisy)
                        printk(KERN_INFO "%s: will probe irqs later\n", d->name);
                pciirq = 0;
        } else if (!pciirq) {
                if (noisy)
                        printk(KERN_WARNING "%s: bad irq (%d): will probe later\n",
                                d->name, pciirq);
                pciirq = 0;
        } else {
                if (d->init_chipset) {
                        ret = d->init_chipset(dev, d->name);
                        if (ret < 0)
                                goto out;
                }
                if (noisy)
                        printk(KERN_INFO "%s: 100%% native mode on irq %d\n",
                                d->name, pciirq);
        }

        /* FIXME: silent failure can happen */

        ide_pci_setup_ports(dev, d, pciirq, idx);
out:
        return ret;
}

int ide_setup_pci_device(struct pci_dev *dev, const struct ide_port_info *d)
{
        u8 idx[4] = { 0xff, 0xff, 0xff, 0xff };
        int ret;

        ret = do_ide_setup_pci_device(dev, d, &idx[0], 1);

        if (ret >= 0)
                ide_device_add(idx);

        return ret;
}

EXPORT_SYMBOL_GPL(ide_setup_pci_device);

int ide_setup_pci_devices(struct pci_dev *dev1, struct pci_dev *dev2,
                          const struct ide_port_info *d)
{
        struct pci_dev *pdev[] = { dev1, dev2 };
        int ret, i;
        u8 idx[4] = { 0xff, 0xff, 0xff, 0xff };

        for (i = 0; i < 2; i++) {
                ret = do_ide_setup_pci_device(pdev[i], d, &idx[i*2], !i);
                /*
                 * FIXME: Mom, mom, they stole me the helper function to undo
                 * do_ide_setup_pci_device() on the first device!
                 */
                if (ret < 0)
                        goto out;
        }

        ide_device_add(idx);
out:
        return ret;
}

EXPORT_SYMBOL_GPL(ide_setup_pci_devices);

#ifdef CONFIG_IDEPCI_PCIBUS_ORDER
/*
 *      Module interfaces
 */
 
static int pre_init = 1;                /* Before first ordered IDE scan */
static LIST_HEAD(ide_pci_drivers);

/*
 *      __ide_pci_register_driver       -       attach IDE driver
 *      @driver: pci driver
 *      @module: owner module of the driver
 *
 *      Registers a driver with the IDE layer. The IDE layer arranges that
 *      boot time setup is done in the expected device order and then 
 *      hands the controllers off to the core PCI code to do the rest of
 *      the work.
 *
 *      Returns are the same as for pci_register_driver
 */

int __ide_pci_register_driver(struct pci_driver *driver, struct module *module,
                              const char *mod_name)
{
        if(!pre_init)
                return __pci_register_driver(driver, module, mod_name);
        driver->driver.owner = module;
        list_add_tail(&driver->node, &ide_pci_drivers);
        return 0;
}

EXPORT_SYMBOL_GPL(__ide_pci_register_driver);

/**
 *      ide_scan_pcidev         -       find an IDE driver for a device
 *      @dev: PCI device to check
 *
 *      Look for an IDE driver to handle the device we are considering.
 *      This is only used during boot up to get the ordering correct. After
 *      boot up the pci layer takes over the job.
 */
 
static int __init ide_scan_pcidev(struct pci_dev *dev)
{
        struct list_head *l;
        struct pci_driver *d;
        
        list_for_each(l, &ide_pci_drivers) {
                d = list_entry(l, struct pci_driver, node);
                if (d->id_table) {
                        const struct pci_device_id *id = pci_match_id(d->id_table,
                                                                      dev);
                        if (id != NULL && d->probe(dev, id) >= 0) {
                                dev->driver = d;
                                pci_dev_get(dev);
                                return 1;
                        }
                }
        }
        return 0;
}

/**
 *      ide_scan_pcibus         -       perform the initial IDE driver scan
 *      @scan_direction: set for reverse order scanning
 *
 *      Perform the initial bus rather than driver ordered scan of the
 *      PCI drivers. After this all IDE pci handling becomes standard
 *      module ordering not traditionally ordered.
 */
        
void __init ide_scan_pcibus (int scan_direction)
{
        struct pci_dev *dev = NULL;
        struct pci_driver *d;
        struct list_head *l, *n;

        pre_init = 0;
        if (!scan_direction)
                while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL)
                        ide_scan_pcidev(dev);
        else
                while ((dev = pci_get_device_reverse(PCI_ANY_ID, PCI_ANY_ID, dev))
                       != NULL)
                        ide_scan_pcidev(dev);
        
        /*
         *      Hand the drivers over to the PCI layer now we
         *      are post init.
         */

        list_for_each_safe(l, n, &ide_pci_drivers) {
                list_del(l);
                d = list_entry(l, struct pci_driver, node);
                if (__pci_register_driver(d, d->driver.owner, d->driver.mod_name))
                        printk(KERN_ERR "%s: failed to register driver for %s\n",
                               __FUNCTION__, d->driver.mod_name);
        }
}
#endif