ide.c

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/*
 *  Copyright (C) 1994-1998     Linus Torvalds & authors (see below)
 *  Copyright (C) 2003-2005, 2007   Bartlomiej Zolnierkiewicz
 */

/*
 *  Mostly written by Mark Lord  <[email protected]>
 *                and Gadi Oxman <[email protected]>
 *                and Andre Hedrick <[email protected]>
 *
 *  See linux/MAINTAINERS for address of current maintainer.
 *
 * This is the multiple IDE interface driver, as evolved from hd.c.
 * It supports up to MAX_HWIFS IDE interfaces, on one or more IRQs
 *   (usually 14 & 15).
 * There can be up to two drives per interface, as per the ATA-2 spec.
 *
 * ...
 *
 *  From hd.c:
 *  |
 *  | It traverses the request-list, using interrupts to jump between functions.
 *  | As nearly all functions can be called within interrupts, we may not sleep.
 *  | Special care is recommended.  Have Fun!
 *  |
 *  | modified by Drew Eckhardt to check nr of hd's from the CMOS.
 *  |
 *  | Thanks to Branko Lankester, [email protected], who found a bug
 *  | in the early extended-partition checks and added DM partitions.
 *  |
 *  | Early work on error handling by Mika Liljeberg ([email protected]).
 *  |
 *  | IRQ-unmask, drive-id, multiple-mode, support for ">16 heads",
 *  | and general streamlining by Mark Lord ([email protected]).
 *
 *  October, 1994 -- Complete line-by-line overhaul for linux 1.1.x, by:
 *
 *  Mark Lord   ([email protected])       (IDE Perf.Pkg)
 *  Delman Lee  ([email protected])       ("Mr. atdisk2")
 *  Scott Snyder    ([email protected])    (ATAPI IDE cd-rom)
 *
 *  This was a rewrite of just about everything from hd.c, though some original
 *  code is still sprinkled about.  Think of it as a major evolution, with
 *  inspiration from lots of linux users, esp.  [email protected]
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/major.h>
#include <linux/errno.h>
#include <linux/genhd.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/ide.h>
#include <linux/hdreg.h>
#include <linux/completion.h>
#include <linux/device.h>

struct class *ide_port_class;

int ide_device_get(ide_drive_t *drive)
{
    struct device *host_dev;
    struct module *module;

    if (!get_device(&drive->gendev))
        return -ENXIO;

    host_dev = drive->hwif->host->dev[0];
    module = host_dev ? host_dev->driver->owner : NULL;

    if (module && !try_module_get(module)) {
        put_device(&drive->gendev);
        return -ENXIO;
    }

    return 0;
}
EXPORT_SYMBOL_GPL(ide_device_get);

void ide_device_put(ide_drive_t *drive)
{
#ifdef CONFIG_MODULE_UNLOAD
    struct device *host_dev = drive->hwif->host->dev[0];
    struct module *module = host_dev ? host_dev->driver->owner : NULL;

    if (module)
        module_put(module);
#endif
    put_device(&drive->gendev);
}
EXPORT_SYMBOL_GPL(ide_device_put);

static int ide_bus_match(struct device *dev, struct device_driver *drv)
{
    return 1;
}

static int ide_uevent(struct device *dev, struct kobj_uevent_env *env)
{
    ide_drive_t *drive = to_ide_device(dev);

    add_uevent_var(env, "MEDIA=%s", ide_media_string(drive));
    add_uevent_var(env, "DRIVENAME=%s", drive->name);
    add_uevent_var(env, "MODALIAS=ide:m-%s", ide_media_string(drive));
    return 0;
}

static int generic_ide_probe(struct device *dev)
{
    ide_drive_t *drive = to_ide_device(dev);
    struct ide_driver *drv = to_ide_driver(dev->driver);

    return drv->probe ? drv->probe(drive) : -ENODEV;
}

static int generic_ide_remove(struct device *dev)
{
    ide_drive_t *drive = to_ide_device(dev);
    struct ide_driver *drv = to_ide_driver(dev->driver);

    if (drv->remove)
        drv->remove(drive);

    return 0;
}

static void generic_ide_shutdown(struct device *dev)
{
    ide_drive_t *drive = to_ide_device(dev);
    struct ide_driver *drv = to_ide_driver(dev->driver);

    if (dev->driver && drv->shutdown)
        drv->shutdown(drive);
}

struct bus_type ide_bus_type = {
    .name       = "ide",
    .match      = ide_bus_match,
    .uevent     = ide_uevent,
    .probe      = generic_ide_probe,
    .remove     = generic_ide_remove,
    .shutdown   = generic_ide_shutdown,
    .dev_attrs  = ide_dev_attrs,
    .suspend    = generic_ide_suspend,
    .resume     = generic_ide_resume,
};

EXPORT_SYMBOL_GPL(ide_bus_type);

int ide_vlb_clk;
EXPORT_SYMBOL_GPL(ide_vlb_clk);

module_param_named(vlb_clock, ide_vlb_clk, int, 0);
MODULE_PARM_DESC(vlb_clock, "VLB clock frequency (in MHz)");

int ide_pci_clk;
EXPORT_SYMBOL_GPL(ide_pci_clk);

module_param_named(pci_clock, ide_pci_clk, int, 0);
MODULE_PARM_DESC(pci_clock, "PCI bus clock frequency (in MHz)");

static int ide_set_dev_param_mask(const char *s, const struct kernel_param *kp)
{
    int a, b, i, j = 1;
    unsigned int *dev_param_mask = (unsigned int *)kp->arg;

    /* controller . device (0 or 1) [ : 1 (set) | 0 (clear) ] */
    if (sscanf(s, "%d.%d:%d", &a, &b, &j) != 3 &&
        sscanf(s, "%d.%d", &a, &b) != 2)
        return -EINVAL;

    i = a * MAX_DRIVES + b;

    if (i >= MAX_HWIFS * MAX_DRIVES || j < 0 || j > 1)
        return -EINVAL;

    if (j)
        *dev_param_mask |= (1 << i);
    else
        *dev_param_mask &= ~(1 << i);

    return 0;
}

static struct kernel_param_ops param_ops_ide_dev_mask = {
    .set = ide_set_dev_param_mask
};

#define param_check_ide_dev_mask(name, p) param_check_uint(name, p)

static unsigned int ide_nodma;

module_param_named(nodma, ide_nodma, ide_dev_mask, 0);
MODULE_PARM_DESC(nodma, "disallow DMA for a device");

static unsigned int ide_noflush;

module_param_named(noflush, ide_noflush, ide_dev_mask, 0);
MODULE_PARM_DESC(noflush, "disable flush requests for a device");

static unsigned int ide_nohpa;

module_param_named(nohpa, ide_nohpa, ide_dev_mask, 0);
MODULE_PARM_DESC(nohpa, "disable Host Protected Area for a device");

static unsigned int ide_noprobe;

module_param_named(noprobe, ide_noprobe, ide_dev_mask, 0);
MODULE_PARM_DESC(noprobe, "skip probing for a device");

static unsigned int ide_nowerr;

module_param_named(nowerr, ide_nowerr, ide_dev_mask, 0);
MODULE_PARM_DESC(nowerr, "ignore the ATA_DF bit for a device");

static unsigned int ide_cdroms;

module_param_named(cdrom, ide_cdroms, ide_dev_mask, 0);
MODULE_PARM_DESC(cdrom, "force device as a CD-ROM");

struct chs_geom {
    unsigned int    cyl;
    u8      head;
    u8      sect;
};

static unsigned int ide_disks;
static struct chs_geom ide_disks_chs[MAX_HWIFS * MAX_DRIVES];

static int ide_set_disk_chs(const char *str, struct kernel_param *kp)
{
    int a, b, c = 0, h = 0, s = 0, i, j = 1;

    /* controller . device (0 or 1) : Cylinders , Heads , Sectors */
    /* controller . device (0 or 1) : 1 (use CHS) | 0 (ignore CHS) */
    if (sscanf(str, "%d.%d:%d,%d,%d", &a, &b, &c, &h, &s) != 5 &&
        sscanf(str, "%d.%d:%d", &a, &b, &j) != 3)
        return -EINVAL;

    i = a * MAX_DRIVES + b;

    if (i >= MAX_HWIFS * MAX_DRIVES || j < 0 || j > 1)
        return -EINVAL;

    if (c > INT_MAX || h > 255 || s > 255)
        return -EINVAL;

    if (j)
        ide_disks |= (1 << i);
    else
        ide_disks &= ~(1 << i);

    ide_disks_chs[i].cyl  = c;
    ide_disks_chs[i].head = h;
    ide_disks_chs[i].sect = s;

    return 0;
}

module_param_call(chs, ide_set_disk_chs, NULL, NULL, 0);
MODULE_PARM_DESC(chs, "force device as a disk (using CHS)");

static void ide_dev_apply_params(ide_drive_t *drive, u8 unit)
{
    int i = drive->hwif->index * MAX_DRIVES + unit;

    if (ide_nodma & (1 << i)) {
        printk(KERN_INFO "ide: disallowing DMA for %s\n", drive->name);
        drive->dev_flags |= IDE_DFLAG_NODMA;
    }
    if (ide_noflush & (1 << i)) {
        printk(KERN_INFO "ide: disabling flush requests for %s\n",
                 drive->name);
        drive->dev_flags |= IDE_DFLAG_NOFLUSH;
    }
    if (ide_nohpa & (1 << i)) {
        printk(KERN_INFO "ide: disabling Host Protected Area for %s\n",
                 drive->name);
        drive->dev_flags |= IDE_DFLAG_NOHPA;
    }
    if (ide_noprobe & (1 << i)) {
        printk(KERN_INFO "ide: skipping probe for %s\n", drive->name);
        drive->dev_flags |= IDE_DFLAG_NOPROBE;
    }
    if (ide_nowerr & (1 << i)) {
        printk(KERN_INFO "ide: ignoring the ATA_DF bit for %s\n",
                 drive->name);
        drive->bad_wstat = BAD_R_STAT;
    }
    if (ide_cdroms & (1 << i)) {
        printk(KERN_INFO "ide: forcing %s as a CD-ROM\n", drive->name);
        drive->dev_flags |= IDE_DFLAG_PRESENT;
        drive->media = ide_cdrom;
        /* an ATAPI device ignores DRDY */
        drive->ready_stat = 0;
    }
    if (ide_disks & (1 << i)) {
        drive->cyl  = drive->bios_cyl  = ide_disks_chs[i].cyl;
        drive->head = drive->bios_head = ide_disks_chs[i].head;
        drive->sect = drive->bios_sect = ide_disks_chs[i].sect;

        printk(KERN_INFO "ide: forcing %s as a disk (%d/%d/%d)\n",
                 drive->name,
                 drive->cyl, drive->head, drive->sect);

        drive->dev_flags |= IDE_DFLAG_FORCED_GEOM | IDE_DFLAG_PRESENT;
        drive->media = ide_disk;
        drive->ready_stat = ATA_DRDY;
    }
}

static unsigned int ide_ignore_cable;

static int ide_set_ignore_cable(const char *s, struct kernel_param *kp)
{
    int i, j = 1;

    /* controller (ignore) */
    /* controller : 1 (ignore) | 0 (use) */
    if (sscanf(s, "%d:%d", &i, &j) != 2 && sscanf(s, "%d", &i) != 1)
        return -EINVAL;

    if (i >= MAX_HWIFS || j < 0 || j > 1)
        return -EINVAL;

    if (j)
        ide_ignore_cable |= (1 << i);
    else
        ide_ignore_cable &= ~(1 << i);

    return 0;
}

module_param_call(ignore_cable, ide_set_ignore_cable, NULL, NULL, 0);
MODULE_PARM_DESC(ignore_cable, "ignore cable detection");

void ide_port_apply_params(ide_hwif_t *hwif)
{
    ide_drive_t *drive;
    int i;

    if (ide_ignore_cable & (1 << hwif->index)) {
        printk(KERN_INFO "ide: ignoring cable detection for %s\n",
                 hwif->name);
        hwif->cbl = ATA_CBL_PATA40_SHORT;
    }

    ide_port_for_each_dev(i, drive, hwif)
        ide_dev_apply_params(drive, i);
}

/*
 * This is gets invoked once during initialization, to set *everything* up
 */
static int __init ide_init(void)
{
    int ret;

    printk(KERN_INFO "Uniform Multi-Platform E-IDE driver\n");

    ret = bus_register(&ide_bus_type);
    if (ret < 0) {
        printk(KERN_WARNING "IDE: bus_register error: %d\n", ret);
        return ret;
    }

    ide_port_class = class_create(THIS_MODULE, "ide_port");
    if (IS_ERR(ide_port_class)) {
        ret = PTR_ERR(ide_port_class);
        goto out_port_class;
    }

    ide_acpi_init();

    proc_ide_create();

    return 0;

out_port_class:
    bus_unregister(&ide_bus_type);

    return ret;
}

static void __exit ide_exit(void)
{
    proc_ide_destroy();

    class_destroy(ide_port_class);

    bus_unregister(&ide_bus_type);
}

module_init(ide_init);
module_exit(ide_exit);

MODULE_LICENSE("GPL");