linux/drivers/acpi/hed.c

/*
 * ACPI Hardware Error Device (PNP0C33) Driver
 *
 * Copyright (C) 2010, Intel Corp.
 *	Author: Huang Ying <ying.huang@intel.com>
 *
 * ACPI Hardware Error Device is used to report some hardware errors
 * notified via SCI, mainly the corrected errors.
 *
 * 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;
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/acpi.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
#include <acpi/hed.h>

static struct acpi_device_id acpi_hed_ids[] = {
	{"PNP0C33", 0},
	{"", 0},
};
MODULE_DEVICE_TABLE(acpi, acpi_hed_ids);

static acpi_handle hed_handle;

static BLOCKING_NOTIFIER_HEAD(acpi_hed_notify_list);

int register_acpi_hed_notifier(struct notifier_block *nb)
{
	return blocking_notifier_chain_register(&acpi_hed_notify_list, nb);
}
EXPORT_SYMBOL_GPL(register_acpi_hed_notifier);

void unregister_acpi_hed_notifier(struct notifier_block *nb)
{
	blocking_notifier_chain_unregister(&acpi_hed_notify_list, nb);
}
EXPORT_SYMBOL_GPL(unregister_acpi_hed_notifier);

/*
 * SCI to report hardware error is forwarded to the listeners of HED,
 * it is used by HEST Generic Hardware Error Source with notify type
 * SCI.
 */
static void acpi_hed_notify(struct acpi_device *device, u32 event)
{
	blocking_notifier_call_chain(&acpi_hed_notify_list, 0, NULL);
}

static int __devinit acpi_hed_add(struct acpi_device *device)
{
	/* Only one hardware error device */
	if (hed_handle)
		return -EINVAL;
	hed_handle = device->handle;
	return 0;
}

static int __devexit acpi_hed_remove(struct acpi_device *device, int type)
{
	hed_handle = NULL;
	return 0;
}

static struct acpi_driver acpi_hed_driver = {
	.name = "hardware_error_device",
	.class = "hardware_error",
	.ids = acpi_hed_ids,
	.ops = {
		.add = acpi_hed_add,
		.remove = acpi_hed_remove,
		.notify = acpi_hed_notify,
	},
};

static int __init acpi_hed_init(void)
{
	if (acpi_disabled)
		return -ENODEV;

	if (acpi_bus_register_driver(&acpi_hed_driver) < 0)
		return -ENODEV;

	return 0;
}

static void __exit acpi_hed_exit(void)
{
	acpi_bus_unregister_driver(&acpi_hed_driver);
}

module_init(acpi_hed_init);
module_exit(acpi_hed_exit);

ACPI_MODULE_NAME("hed");
MODULE_AUTHOR("Huang Ying");
MODULE_DESCRIPTION("ACPI Hardware Error Device Driver");
MODULE_LICENSE("GPL");