/*
   * acpi_container.c  - ACPI Generic Container Driver
   * ($Revision: )
   *
   * Copyright (C) 2004 Anil S Keshavamurthy (anil.s.keshavamurthy@intel.com)
   * Copyright (C) 2004 Keiichiro Tokunaga (tokunaga.keiich@jp.fujitsu.com)
   * Copyright (C) 2004 Motoyuki Ito (motoyuki@soft.fujitsu.com)
   * Copyright (C) 2004 Intel Corp.
   * Copyright (C) 2004 FUJITSU LIMITED
   *
   * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   *
   *  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.,
   *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
   *
   * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   */
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/init.h>

  #include <linux/slab.h>

  #include <linux/types.h>
  #include <linux/acpi.h>
  #include <acpi/acpi_bus.h>
  #include <acpi/acpi_drivers.h>
  #include <acpi/container.h>

  #define PREFIX "ACPI: "

  #define ACPI_CONTAINER_DEVICE_NAME	"ACPI container device"
  #define ACPI_CONTAINER_CLASS		"container"
  
  #define INSTALL_NOTIFY_HANDLER		1
  #define UNINSTALL_NOTIFY_HANDLER	2

  #define _COMPONENT			ACPI_CONTAINER_COMPONENT

  ACPI_MODULE_NAME("container");

  MODULE_AUTHOR("Anil S Keshavamurthy");

  MODULE_DESCRIPTION("ACPI container driver");

  MODULE_LICENSE("GPL");

  static int acpi_container_add(struct acpi_device *device);
  static int acpi_container_remove(struct acpi_device *device, int type);

  static const struct acpi_device_id container_device_ids[] = {
  	{"ACPI0004", 0},
  	{"PNP0A05", 0},
  	{"PNP0A06", 0},
  	{"", 0},
  };
  MODULE_DEVICE_TABLE(acpi, container_device_ids);

  static struct acpi_driver acpi_container_driver = {

  	.name = "container",

  	.class = ACPI_CONTAINER_CLASS,

  	.ids = container_device_ids,

  	.ops = {
  		.add = acpi_container_add,
  		.remove = acpi_container_remove,
  		},

  };

  /*******************************************************************/

  static int is_device_present(acpi_handle handle)

  {

  	acpi_handle temp;
  	acpi_status status;

  	unsigned long long sta;

  
  	status = acpi_get_handle(handle, "_STA", &temp);
  	if (ACPI_FAILURE(status))

  		return 1;	/* _STA not found, assume device present */

  
  	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
  	if (ACPI_FAILURE(status))

  		return 0;	/* Firmware error */

  	return ((sta & ACPI_STA_DEVICE_PRESENT) == ACPI_STA_DEVICE_PRESENT);

  }
  
  /*******************************************************************/

  static int acpi_container_add(struct acpi_device *device)

  {
  	struct acpi_container *container;

  
  	if (!device) {

  		printk(KERN_ERR PREFIX "device is NULL
  ");

  		return -EINVAL;

  	}

  	container = kzalloc(sizeof(struct acpi_container), GFP_KERNEL);

  	if (!container)

  		return -ENOMEM;

  	container->handle = device->handle;
  	strcpy(acpi_device_name(device), ACPI_CONTAINER_DEVICE_NAME);
  	strcpy(acpi_device_class(device), ACPI_CONTAINER_CLASS);

  	device->driver_data = container;

  	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device <%s> bid <%s>
  ",
  			  acpi_device_name(device), acpi_device_bid(device)));

  	return 0;

  }

  static int acpi_container_remove(struct acpi_device *device, int type)

  {

  	acpi_status status = AE_OK;
  	struct acpi_container *pc = NULL;

  	pc = acpi_driver_data(device);

  	kfree(pc);

  	return status;
  }

  static int container_device_add(struct acpi_device **device, acpi_handle handle)

  {
  	acpi_handle phandle;
  	struct acpi_device *pdev;
  	int result;

  
  	if (acpi_get_parent(handle, &phandle)) {

  		return -ENODEV;

  	}
  
  	if (acpi_bus_get_device(phandle, &pdev)) {

  		return -ENODEV;

  	}
  
  	if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_DEVICE)) {

  		return -ENODEV;

  	}

  	result = acpi_bus_start(*device);

  	return result;

  }

  static void container_notify_cb(acpi_handle handle, u32 type, void *context)

  {

  	struct acpi_device *device = NULL;

  	int result;
  	int present;
  	acpi_status status;

  
  	present = is_device_present(handle);

  	switch (type) {
  	case ACPI_NOTIFY_BUS_CHECK:
  		/* Fall through */
  	case ACPI_NOTIFY_DEVICE_CHECK:

  		printk(KERN_WARNING "Container driver received %s event
  ",

  		       (type == ACPI_NOTIFY_BUS_CHECK) ?
  		       "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK");

  		status = acpi_bus_get_device(handle, &device);
  		if (present) {
  			if (ACPI_FAILURE(status) || !device) {
  				result = container_device_add(&device, handle);
  				if (!result)

  					kobject_uevent(&device->dev.kobj,

  						       KOBJ_ONLINE);

  				else

  					printk(KERN_WARNING
  					       "Failed to add container
  ");

  			}
  		} else {
  			if (ACPI_SUCCESS(status)) {
  				/* device exist and this is a remove request */

  				kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE);

  			}
  		}
  		break;
  	case ACPI_NOTIFY_EJECT_REQUEST:
  		if (!acpi_bus_get_device(handle, &device) && device) {

  			kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE);

  		}
  		break;
  	default:
  		break;
  	}

  	return;

  }
  
  static acpi_status
  container_walk_namespace_cb(acpi_handle handle,

  			    u32 lvl, void *context, void **rv)

  {

  	char *hid = NULL;

  	struct acpi_device_info *info;
  	acpi_status status;
  	int *action = context;

  	status = acpi_get_object_info(handle, &info);
  	if (ACPI_FAILURE(status)) {

  		return AE_OK;

  	}

  	if (info->valid & ACPI_VALID_HID)

  		hid = info->hardware_id.string;

  
  	if (hid == NULL) {
  		goto end;
  	}
  
  	if (strcmp(hid, "ACPI0004") && strcmp(hid, "PNP0A05") &&

  	    strcmp(hid, "PNP0A06")) {

  		goto end;
  	}

  	switch (*action) {

  	case INSTALL_NOTIFY_HANDLER:
  		acpi_install_notify_handler(handle,

  					    ACPI_SYSTEM_NOTIFY,
  					    container_notify_cb, NULL);

  		break;
  	case UNINSTALL_NOTIFY_HANDLER:
  		acpi_remove_notify_handler(handle,

  					   ACPI_SYSTEM_NOTIFY,
  					   container_notify_cb);

  		break;
  	default:
  		break;
  	}

        end:

  	kfree(info);

  	return AE_OK;

  }

  static int __init acpi_container_init(void)

  {

  	int result = 0;
  	int action = INSTALL_NOTIFY_HANDLER;

  
  	result = acpi_bus_register_driver(&acpi_container_driver);
  	if (result < 0) {

  		return (result);

  	}
  
  	/* register notify handler to every container device */
  	acpi_walk_namespace(ACPI_TYPE_DEVICE,

  			    ACPI_ROOT_OBJECT,
  			    ACPI_UINT32_MAX,

  			    container_walk_namespace_cb, NULL, &action, NULL);

  	return (0);

  }

  static void __exit acpi_container_exit(void)

  {

  	int action = UNINSTALL_NOTIFY_HANDLER;

  
  	acpi_walk_namespace(ACPI_TYPE_DEVICE,

  			    ACPI_ROOT_OBJECT,
  			    ACPI_UINT32_MAX,

  			    container_walk_namespace_cb, NULL, &action, NULL);

  
  	acpi_bus_unregister_driver(&acpi_container_driver);

  	return;

  }
  
  module_init(acpi_container_init);
  module_exit(acpi_container_exit);