ide-generic: add ide_generic class and attribute for adding new interfaces

/*

 * generic/default IDE host driver

 *

 * Copyright (C) 2004 Bartlomiej Zolnierkiewicz

 * Copyright (C) 2004, 2008 Bartlomiej Zolnierkiewicz

 * This code was split off from ide.c.  See it for original copyrights.

 *

 * May be copied or modified under the terms of the GNU General Public License.

 */

/*

 * For special cases new interfaces may be added using sysfs, i.e.

 *

 *	echo -n "0x168:0x36e:10" > /sys/class/ide_generic/add

 *

 * will add an interface using I/O ports 0x168-0x16f/0x36e and IRQ 10.

 */

#include <linux/kernel.h>

#include <linux/init.h>

#include <linux/module.h>

#include <linux/ide.h>

#define DRV_NAME	"ide_generic"

static ssize_t store_add(struct class *cls, const char *buf, size_t n)

{

	ide_hwif_t *hwif;

	unsigned int base, ctl;

	int irq;

	hw_regs_t hw;

	u8 idx[] = { 0xff, 0xff, 0xff, 0xff };

	if (sscanf(buf, "%x:%x:%d", &base, &ctl, &irq) != 3)

		return -EINVAL;

	hwif = ide_find_port(base);

	if (hwif == NULL)

		return -ENOENT;

	memset(&hw, 0, sizeof(hw));

	ide_std_init_ports(&hw, base, ctl);

	hw.irq = irq;

	hw.chipset = ide_generic;

	ide_init_port_hw(hwif, &hw);

	idx[0] = hwif->index;

	ide_device_add(idx, NULL);

	return n;

};

static struct class_attribute ide_generic_class_attrs[] = {

	__ATTR(add, S_IWUSR, NULL, store_add),

	__ATTR_NULL

};

static void ide_generic_class_release(struct class *cls)

{

	kfree(cls);

}

static int __init ide_generic_sysfs_init(void)

{

	struct class *cls;

	int rc;

	cls = kzalloc(sizeof(*cls), GFP_KERNEL);

	if (!cls)

		return -ENOMEM;

	cls->name = DRV_NAME;

	cls->owner = THIS_MODULE;

	cls->class_release = ide_generic_class_release;

	cls->class_attrs = ide_generic_class_attrs;

	rc = class_register(cls);

	if (rc) {

		kfree(cls);

		return rc;

	}

	return 0;

}

static int __init ide_generic_init(void)

{

	u8 idx[MAX_HWIFS];

	ide_device_add_all(idx, NULL);

	if (ide_generic_sysfs_init())

		printk(KERN_ERR DRV_NAME ": failed to create ide_generic "

					 "class\n");

	return 0;

}