[linux-block.git] / drivers / acpi / acpi_memhotplug.c

/*
 * Copyright (C) 2004 Intel Corporation <naveen.b.s@intel.com>
 *
 * All rights reserved.
 *
 * 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, GOOD TITLE or
 * NON INFRINGEMENT.  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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *
 * ACPI based HotPlug driver that supports Memory Hotplug
 * This driver fields notifications from firmare for memory add
 * and remove operations and alerts the VM of the affected memory
 * ranges.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/memory_hotplug.h>
#include <acpi/acpi_drivers.h>

#define ACPI_MEMORY_DEVICE_COMPONENT		0x08000000UL
#define ACPI_MEMORY_DEVICE_CLASS		"memory"
#define ACPI_MEMORY_DEVICE_HID			"PNP0C80"
#define ACPI_MEMORY_DEVICE_DRIVER_NAME		"Hotplug Mem Driver"
#define ACPI_MEMORY_DEVICE_NAME			"Hotplug Mem Device"

#define _COMPONENT		ACPI_MEMORY_DEVICE_COMPONENT

ACPI_MODULE_NAME("acpi_memory")
    MODULE_AUTHOR("Naveen B S <naveen.b.s@intel.com>");
MODULE_DESCRIPTION(ACPI_MEMORY_DEVICE_DRIVER_NAME);
MODULE_LICENSE("GPL");

/* ACPI _STA method values */
#define ACPI_MEMORY_STA_PRESENT		(0x00000001UL)
#define ACPI_MEMORY_STA_ENABLED		(0x00000002UL)
#define ACPI_MEMORY_STA_FUNCTIONAL	(0x00000008UL)

/* Memory Device States */
#define MEMORY_INVALID_STATE	0
#define MEMORY_POWER_ON_STATE	1
#define MEMORY_POWER_OFF_STATE	2

static int acpi_memory_device_add(struct acpi_device *device);
static int acpi_memory_device_remove(struct acpi_device *device, int type);
static int acpi_memory_device_start(struct acpi_device *device);

static struct acpi_driver acpi_memory_device_driver = {
	.name = ACPI_MEMORY_DEVICE_DRIVER_NAME,
	.class = ACPI_MEMORY_DEVICE_CLASS,
	.ids = ACPI_MEMORY_DEVICE_HID,
	.ops = {
		.add = acpi_memory_device_add,
		.remove = acpi_memory_device_remove,
		.start = acpi_memory_device_start,
		},
};

struct acpi_memory_info {
	struct list_head list;
	u64 start_addr;		/* Memory Range start physical addr */
	u64 length;		/* Memory Range length */
	unsigned short caching;	/* memory cache attribute */
	unsigned short write_protect;	/* memory read/write attribute */
	unsigned int enabled:1;
};

struct acpi_memory_device {
	struct acpi_device * device;
	unsigned int state;	/* State of the memory device */
	struct list_head res_list;
};

static acpi_status
acpi_memory_get_resource(struct acpi_resource *resource, void *context)
{
	struct acpi_memory_device *mem_device = context;
	struct acpi_resource_address64 address64;
	struct acpi_memory_info *info, *new;
	acpi_status status;

	status = acpi_resource_to_address64(resource, &address64);
	if (ACPI_FAILURE(status) ||
	    (address64.resource_type != ACPI_MEMORY_RANGE))
		return AE_OK;

	list_for_each_entry(info, &mem_device->res_list, list) {
		/* Can we combine the resource range information? */
		if ((info->caching == address64.info.mem.caching) &&
		    (info->write_protect == address64.info.mem.write_protect) &&
		    (info->start_addr + info->length == address64.minimum)) {
			info->length += address64.address_length;
			return AE_OK;
		}
	}

	new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL);
	if (!new)
		return AE_ERROR;

	INIT_LIST_HEAD(&new->list);
	new->caching = address64.info.mem.caching;
	new->write_protect = address64.info.mem.write_protect;
	new->start_addr = address64.minimum;
	new->length = address64.address_length;
	list_add_tail(&new->list, &mem_device->res_list);

	return AE_OK;
}

static int
acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
{
	acpi_status status;
	struct acpi_memory_info *info, *n;


	status = acpi_walk_resources(mem_device->device->handle, METHOD_NAME__CRS,
				     acpi_memory_get_resource, mem_device);
	if (ACPI_FAILURE(status)) {
		list_for_each_entry_safe(info, n, &mem_device->res_list, list)
			kfree(info);
		return -EINVAL;
	}

	return 0;
}

static int
acpi_memory_get_device(acpi_handle handle,
		       struct acpi_memory_device **mem_device)
{
	acpi_status status;
	acpi_handle phandle;
	struct acpi_device *device = NULL;
	struct acpi_device *pdevice = NULL;


	if (!acpi_bus_get_device(handle, &device) && device)
		goto end;

	status = acpi_get_parent(handle, &phandle);
	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status, "Cannot find acpi parent"));
		return -EINVAL;
	}

	/* Get the parent device */
	status = acpi_bus_get_device(phandle, &pdevice);
	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status, "Cannot get acpi bus device"));
		return -EINVAL;
	}

	/*
	 * Now add the notified device.  This creates the acpi_device
	 * and invokes .add function
	 */
	status = acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE);
	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status, "Cannot add acpi bus"));
		return -EINVAL;
	}

      end:
	*mem_device = acpi_driver_data(device);
	if (!(*mem_device)) {
		printk(KERN_ERR "\n driver data not found");
		return -ENODEV;
	}

	return 0;
}

static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
{
	unsigned long current_status;


	/* Get device present/absent information from the _STA */
	if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->device->handle, "_STA",
					       NULL, &current_status)))
		return -ENODEV;
	/*
	 * Check for device status. Device should be
	 * present/enabled/functioning.
	 */
	if (!((current_status & ACPI_MEMORY_STA_PRESENT)
	      && (current_status & ACPI_MEMORY_STA_ENABLED)
	      && (current_status & ACPI_MEMORY_STA_FUNCTIONAL)))
		return -ENODEV;

	return 0;
}

static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
{
	int result, num_enabled = 0;
	struct acpi_memory_info *info;
	int node;


	/* Get the range from the _CRS */
	result = acpi_memory_get_device_resources(mem_device);
	if (result) {
		printk(KERN_ERR PREFIX "get_device_resources failed\n");
		mem_device->state = MEMORY_INVALID_STATE;
		return result;
	}

	node = acpi_get_node(mem_device->device->handle);
	/*
	 * Tell the VM there is more memory here...
	 * Note: Assume that this function returns zero on success
	 * We don't have memory-hot-add rollback function,now.
	 * (i.e. memory-hot-remove function)
	 */
	list_for_each_entry(info, &mem_device->res_list, list) {
		if (info->enabled) { /* just sanity check...*/
			num_enabled++;
			continue;
		}
		result = add_memory(node, info->start_addr, info->length);
		if (result)
			continue;
		info->enabled = 1;
		num_enabled++;
	}
	if (!num_enabled) {
		printk(KERN_ERR PREFIX "add_memory failed\n");
		mem_device->state = MEMORY_INVALID_STATE;
		return -EINVAL;
	}

	return result;
}

static int acpi_memory_powerdown_device(struct acpi_memory_device *mem_device)
{
	acpi_status status;
	struct acpi_object_list arg_list;
	union acpi_object arg;
	unsigned long current_status;


	/* Issue the _EJ0 command */
	arg_list.count = 1;
	arg_list.pointer = &arg;
	arg.type = ACPI_TYPE_INTEGER;
	arg.integer.value = 1;
	status = acpi_evaluate_object(mem_device->device->handle,
				      "_EJ0", &arg_list, NULL);
	/* Return on _EJ0 failure */
	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status, "_EJ0 failed"));
		return -ENODEV;
	}

	/* Evalute _STA to check if the device is disabled */
	status = acpi_evaluate_integer(mem_device->device->handle, "_STA",
				       NULL, &current_status);
	if (ACPI_FAILURE(status))
		return -ENODEV;

	/* Check for device status.  Device should be disabled */
	if (current_status & ACPI_MEMORY_STA_ENABLED)
		return -EINVAL;

	return 0;
}

static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
{
	int result;
	struct acpi_memory_info *info, *n;


	/*
	 * Ask the VM to offline this memory range.
	 * Note: Assume that this function returns zero on success
	 */
	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
		if (info->enabled) {
			result = remove_memory(info->start_addr, info->length);
			if (result)
				return result;
		}
		kfree(info);
	}

	/* Power-off and eject the device */
	result = acpi_memory_powerdown_device(mem_device);
	if (result) {
		/* Set the status of the device to invalid */
		mem_device->state = MEMORY_INVALID_STATE;
		return result;
	}

	mem_device->state = MEMORY_POWER_OFF_STATE;
	return result;
}

static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
{
	struct acpi_memory_device *mem_device;
	struct acpi_device *device;


	switch (event) {
	case ACPI_NOTIFY_BUS_CHECK:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "\nReceived BUS CHECK notification for device\n"));
		/* Fall Through */
	case ACPI_NOTIFY_DEVICE_CHECK:
		if (event == ACPI_NOTIFY_DEVICE_CHECK)
			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
					  "\nReceived DEVICE CHECK notification for device\n"));
		if (acpi_memory_get_device(handle, &mem_device)) {
			printk(KERN_ERR PREFIX "Cannot find driver data\n");
			return;
		}

		if (!acpi_memory_check_device(mem_device)) {
			if (acpi_memory_enable_device(mem_device))
				printk(KERN_ERR PREFIX
					    "Cannot enable memory device\n");
		}
		break;
	case ACPI_NOTIFY_EJECT_REQUEST:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "\nReceived EJECT REQUEST notification for device\n"));

		if (acpi_bus_get_device(handle, &device)) {
			printk(KERN_ERR PREFIX "Device doesn't exist\n");
			break;
		}
		mem_device = acpi_driver_data(device);
		if (!mem_device) {
			printk(KERN_ERR PREFIX "Driver Data is NULL\n");
			break;
		}

		/*
		 * Currently disabling memory device from kernel mode
		 * TBD: Can also be disabled from user mode scripts
		 * TBD: Can also be disabled by Callback registration
		 *      with generic sysfs driver
		 */
		if (acpi_memory_disable_device(mem_device))
			printk(KERN_ERR PREFIX
				    "Disable memory device\n");
		/*
		 * TBD: Invoke acpi_bus_remove to cleanup data structures
		 */
		break;
	default:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Unsupported event [0x%x]\n", event));
		break;
	}

	return;
}

static int acpi_memory_device_add(struct acpi_device *device)
{
	int result;
	struct acpi_memory_device *mem_device = NULL;


	if (!device)
		return -EINVAL;

	mem_device = kmalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
	if (!mem_device)
		return -ENOMEM;
	memset(mem_device, 0, sizeof(struct acpi_memory_device));

	INIT_LIST_HEAD(&mem_device->res_list);
	mem_device->device = device;
	sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
	sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
	acpi_driver_data(device) = mem_device;

	/* Get the range from the _CRS */
	result = acpi_memory_get_device_resources(mem_device);
	if (result) {
		kfree(mem_device);
		return result;
	}

	/* Set the device state */
	mem_device->state = MEMORY_POWER_ON_STATE;

	printk(KERN_INFO "%s \n", acpi_device_name(device));

	return result;
}

static int acpi_memory_device_remove(struct acpi_device *device, int type)
{
	struct acpi_memory_device *mem_device = NULL;


	if (!device || !acpi_driver_data(device))
		return -EINVAL;

	mem_device = (struct acpi_memory_device *)acpi_driver_data(device);
	kfree(mem_device);

	return 0;
}

static int acpi_memory_device_start (struct acpi_device *device)
{
	struct acpi_memory_device *mem_device;
	int result = 0;

	mem_device = acpi_driver_data(device);

	if (!acpi_memory_check_device(mem_device)) {
		/* call add_memory func */
		result = acpi_memory_enable_device(mem_device);
		if (result)
			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
				"Error in acpi_memory_enable_device\n"));
	}
	return result;
}

/*
 * Helper function to check for memory device
 */
static acpi_status is_memory_device(acpi_handle handle)
{
	char *hardware_id;
	acpi_status status;
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	struct acpi_device_info *info;


	status = acpi_get_object_info(handle, &buffer);
	if (ACPI_FAILURE(status))
		return status;

	info = buffer.pointer;
	if (!(info->valid & ACPI_VALID_HID)) {
		kfree(buffer.pointer);
		return AE_ERROR;
	}

	hardware_id = info->hardware_id.value;
	if ((hardware_id == NULL) ||
	    (strcmp(hardware_id, ACPI_MEMORY_DEVICE_HID)))
		status = AE_ERROR;

	kfree(buffer.pointer);
	return status;
}

static acpi_status
acpi_memory_register_notify_handler(acpi_handle handle,
				    u32 level, void *ctxt, void **retv)
{
	acpi_status status;


	status = is_memory_device(handle);
	if (ACPI_FAILURE(status)){
		ACPI_EXCEPTION((AE_INFO, status, "handle is no memory device"));
		return AE_OK;	/* continue */
	}

	status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
					     acpi_memory_device_notify, NULL);
	/* continue */
	return AE_OK;
}

static acpi_status
acpi_memory_deregister_notify_handler(acpi_handle handle,
				      u32 level, void *ctxt, void **retv)
{
	acpi_status status;


	status = is_memory_device(handle);
	if (ACPI_FAILURE(status)){
		ACPI_EXCEPTION((AE_INFO, status, "handle is no memory device"));
		return AE_OK;	/* continue */
	}

	status = acpi_remove_notify_handler(handle,
					    ACPI_SYSTEM_NOTIFY,
					    acpi_memory_device_notify);

	return AE_OK;	/* continue */
}

static int __init acpi_memory_device_init(void)
{
	int result;
	acpi_status status;


	result = acpi_bus_register_driver(&acpi_memory_device_driver);

	if (result < 0)
		return -ENODEV;

	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
				     ACPI_UINT32_MAX,
				     acpi_memory_register_notify_handler,
				     NULL, NULL);

	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
		acpi_bus_unregister_driver(&acpi_memory_device_driver);
		return -ENODEV;
	}

	return 0;
}

static void __exit acpi_memory_device_exit(void)
{
	acpi_status status;


	/*
	 * Adding this to un-install notification handlers for all the device
	 * handles.
	 */
	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
				     ACPI_UINT32_MAX,
				     acpi_memory_deregister_notify_handler,
				     NULL, NULL);

	if (ACPI_FAILURE(status))
		ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));

	acpi_bus_unregister_driver(&acpi_memory_device_driver);

	return;
}

module_init(acpi_memory_device_init);
module_exit(acpi_memory_device_exit);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Copyright (C) 2004 Intel Corporation <naveen.b.s@intel.com>
	3	*
	4	* All rights reserved.
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or (at
	9	* your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful, but
	12	* WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
	14	* NON INFRINGEMENT. See the GNU General Public License for more
	15	* details.
	16	*
	17	* You should have received a copy of the GNU General Public License
	18	* along with this program; if not, write to the Free Software
	19	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	20	*
	21	*
	22	* ACPI based HotPlug driver that supports Memory Hotplug
	23	* This driver fields notifications from firmare for memory add
	24	* and remove operations and alerts the VM of the affected memory
	25	* ranges.
	26	*/
	27
	28	#include <linux/kernel.h>
	29	#include <linux/module.h>
	30	#include <linux/init.h>
	31	#include <linux/types.h>
	32	#include <linux/memory_hotplug.h>
	33	#include <acpi/acpi_drivers.h>
	34
1da177e4 LT	35	#define ACPI_MEMORY_DEVICE_COMPONENT 0x08000000UL
	36	#define ACPI_MEMORY_DEVICE_CLASS "memory"
	37	#define ACPI_MEMORY_DEVICE_HID "PNP0C80"
	38	#define ACPI_MEMORY_DEVICE_DRIVER_NAME "Hotplug Mem Driver"
	39	#define ACPI_MEMORY_DEVICE_NAME "Hotplug Mem Device"
	40
	41	#define _COMPONENT ACPI_MEMORY_DEVICE_COMPONENT
	42
4be44fcd LB	43	ACPI_MODULE_NAME("acpi_memory")
4be44fcd LB	44	MODULE_AUTHOR("Naveen B S <naveen.b.s@intel.com>");
1da177e4 LT	45	MODULE_DESCRIPTION(ACPI_MEMORY_DEVICE_DRIVER_NAME);
	46	MODULE_LICENSE("GPL");
	47
	48	/* ACPI _STA method values */
	49	#define ACPI_MEMORY_STA_PRESENT (0x00000001UL)
	50	#define ACPI_MEMORY_STA_ENABLED (0x00000002UL)
	51	#define ACPI_MEMORY_STA_FUNCTIONAL (0x00000008UL)
	52
	53	/* Memory Device States */
	54	#define MEMORY_INVALID_STATE 0
	55	#define MEMORY_POWER_ON_STATE 1
	56	#define MEMORY_POWER_OFF_STATE 2
	57
4be44fcd LB	58	static int acpi_memory_device_add(struct acpi_device *device);
4be44fcd LB	59	static int acpi_memory_device_remove(struct acpi_device *device, int type);
1f425994	60	static int acpi_memory_device_start(struct acpi_device *device);
1da177e4 LT	61
1da177e4 LT	62	static struct acpi_driver acpi_memory_device_driver = {
4be44fcd LB	63	.name = ACPI_MEMORY_DEVICE_DRIVER_NAME,
	64	.class = ACPI_MEMORY_DEVICE_CLASS,
	65	.ids = ACPI_MEMORY_DEVICE_HID,
	66	.ops = {
	67	.add = acpi_memory_device_add,
	68	.remove = acpi_memory_device_remove,
1f425994	69	.start = acpi_memory_device_start,
4be44fcd	70	},
1da177e4 LT	71	};
1da177e4 LT	72
9ac02398 KH	73	struct acpi_memory_info {
	74	struct list_head list;
	75	u64 start_addr; /* Memory Range start physical addr */
	76	u64 length; /* Memory Range length */
	77	unsigned short caching; /* memory cache attribute */
	78	unsigned short write_protect; /* memory read/write attribute */
	79	unsigned int enabled:1;
	80	};
	81
1da177e4	82	struct acpi_memory_device {
3b74863d	83	struct acpi_device * device;
4be44fcd	84	unsigned int state; /* State of the memory device */
9ac02398	85	struct list_head res_list;
1da177e4 LT	86	};
1da177e4 LT	87
9ac02398 KH	88	static acpi_status
	89	acpi_memory_get_resource(struct acpi_resource resource, void context)
	90	{
	91	struct acpi_memory_device *mem_device = context;
	92	struct acpi_resource_address64 address64;
	93	struct acpi_memory_info info, new;
	94	acpi_status status;
	95
	96	status = acpi_resource_to_address64(resource, &address64);
	97	if (ACPI_FAILURE(status) \|\|
	98	(address64.resource_type != ACPI_MEMORY_RANGE))
	99	return AE_OK;
	100
	101	list_for_each_entry(info, &mem_device->res_list, list) {
	102	/* Can we combine the resource range information? */
	103	if ((info->caching == address64.info.mem.caching) &&
	104	(info->write_protect == address64.info.mem.write_protect) &&
	105	(info->start_addr + info->length == address64.minimum)) {
	106	info->length += address64.address_length;
	107	return AE_OK;
	108	}
	109	}
	110
	111	new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL);
	112	if (!new)
	113	return AE_ERROR;
	114
	115	INIT_LIST_HEAD(&new->list);
	116	new->caching = address64.info.mem.caching;
	117	new->write_protect = address64.info.mem.write_protect;
	118	new->start_addr = address64.minimum;
	119	new->length = address64.address_length;
	120	list_add_tail(&new->list, &mem_device->res_list);
	121
	122	return AE_OK;
	123	}
	124
1da177e4 LT	125	static int
	126	acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
	127	{
	128	acpi_status status;
9ac02398	129	struct acpi_memory_info info, n;
1da177e4	130
1da177e4	131
b8632785	132	status = acpi_walk_resources(mem_device->device->handle, METHOD_NAME__CRS,
9ac02398 KH	133	acpi_memory_get_resource, mem_device);
	134	if (ACPI_FAILURE(status)) {
	135	list_for_each_entry_safe(info, n, &mem_device->res_list, list)
	136	kfree(info);
d550d98d	137	return -EINVAL;
1da177e4 LT	138	}
1da177e4 LT	139
d550d98d	140	return 0;
1da177e4 LT	141	}
	142
	143	static int
	144	acpi_memory_get_device(acpi_handle handle,
4be44fcd	145	struct acpi_memory_device **mem_device)
1da177e4 LT	146	{
	147	acpi_status status;
	148	acpi_handle phandle;
	149	struct acpi_device *device = NULL;
	150	struct acpi_device *pdevice = NULL;
	151
1da177e4 LT	152
	153	if (!acpi_bus_get_device(handle, &device) && device)
	154	goto end;
	155
	156	status = acpi_get_parent(handle, &phandle);
	157	if (ACPI_FAILURE(status)) {
a6fc6720	158	ACPI_EXCEPTION((AE_INFO, status, "Cannot find acpi parent"));
d550d98d	159	return -EINVAL;
1da177e4 LT	160	}
	161
	162	/* Get the parent device */
	163	status = acpi_bus_get_device(phandle, &pdevice);
	164	if (ACPI_FAILURE(status)) {
a6fc6720	165	ACPI_EXCEPTION((AE_INFO, status, "Cannot get acpi bus device"));
d550d98d	166	return -EINVAL;
1da177e4 LT	167	}
	168
	169	/*
	170	* Now add the notified device. This creates the acpi_device
	171	* and invokes .add function
	172	*/
	173	status = acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE);
	174	if (ACPI_FAILURE(status)) {
a6fc6720	175	ACPI_EXCEPTION((AE_INFO, status, "Cannot add acpi bus"));
d550d98d	176	return -EINVAL;
1da177e4 LT	177	}
1da177e4 LT	178
4be44fcd	179	end:
1da177e4 LT	180	*mem_device = acpi_driver_data(device);
1da177e4 LT	181	if (!(*mem_device)) {
4be44fcd	182	printk(KERN_ERR "\n driver data not found");
d550d98d	183	return -ENODEV;
1da177e4 LT	184	}
1da177e4 LT	185
d550d98d	186	return 0;
1da177e4 LT	187	}
1da177e4 LT	188
4be44fcd	189	static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
1da177e4 LT	190	{
	191	unsigned long current_status;
	192
1da177e4 LT	193
1da177e4 LT	194	/* Get device present/absent information from the _STA */
b8632785	195	if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->device->handle, "_STA",
4be44fcd	196	NULL, &current_status)))
d550d98d	197	return -ENODEV;
1da177e4 LT	198	/*
	199	* Check for device status. Device should be
	200	* present/enabled/functioning.
	201	*/
	202	if (!((current_status & ACPI_MEMORY_STA_PRESENT)
4be44fcd LB	203	&& (current_status & ACPI_MEMORY_STA_ENABLED)
4be44fcd LB	204	&& (current_status & ACPI_MEMORY_STA_FUNCTIONAL)))
d550d98d	205	return -ENODEV;
1da177e4	206
d550d98d	207	return 0;
1da177e4 LT	208	}
1da177e4 LT	209
4be44fcd	210	static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
1da177e4	211	{
9ac02398 KH	212	int result, num_enabled = 0;
9ac02398 KH	213	struct acpi_memory_info *info;
1e3590e2	214	int node;
1da177e4	215
1da177e4 LT	216
	217	/* Get the range from the _CRS */
	218	result = acpi_memory_get_device_resources(mem_device);
	219	if (result) {
6468463a	220	printk(KERN_ERR PREFIX "get_device_resources failed\n");
1da177e4 LT	221	mem_device->state = MEMORY_INVALID_STATE;
	222	return result;
	223	}
	224
b8632785	225	node = acpi_get_node(mem_device->device->handle);
1da177e4 LT	226	/*
	227	* Tell the VM there is more memory here...
	228	* Note: Assume that this function returns zero on success
9ac02398 KH	229	* We don't have memory-hot-add rollback function,now.
9ac02398 KH	230	* (i.e. memory-hot-remove function)
1da177e4	231	*/
9ac02398	232	list_for_each_entry(info, &mem_device->res_list, list) {
fa25d8d6	233	if (info->enabled) { /* just sanity check...*/
dd56a8e3 YG	234	num_enabled++;
	235	continue;
	236	}
bc02af93	237	result = add_memory(node, info->start_addr, info->length);
9ac02398 KH	238	if (result)
	239	continue;
	240	info->enabled = 1;
	241	num_enabled++;
	242	}
	243	if (!num_enabled) {
0a1f1ab8	244	printk(KERN_ERR PREFIX "add_memory failed\n");
1da177e4	245	mem_device->state = MEMORY_INVALID_STATE;
9ac02398	246	return -EINVAL;
1da177e4 LT	247	}
	248
	249	return result;
	250	}
	251
4be44fcd	252	static int acpi_memory_powerdown_device(struct acpi_memory_device *mem_device)
1da177e4 LT	253	{
1da177e4 LT	254	acpi_status status;
4be44fcd	255	struct acpi_object_list arg_list;
1da177e4 LT	256	union acpi_object arg;
	257	unsigned long current_status;
	258
1da177e4 LT	259
	260	/* Issue the _EJ0 command */
	261	arg_list.count = 1;
	262	arg_list.pointer = &arg;
	263	arg.type = ACPI_TYPE_INTEGER;
	264	arg.integer.value = 1;
b8632785	265	status = acpi_evaluate_object(mem_device->device->handle,
4be44fcd	266	"_EJ0", &arg_list, NULL);
1da177e4 LT	267	/* Return on _EJ0 failure */
1da177e4 LT	268	if (ACPI_FAILURE(status)) {
a6fc6720	269	ACPI_EXCEPTION((AE_INFO, status, "_EJ0 failed"));
d550d98d	270	return -ENODEV;
1da177e4 LT	271	}
	272
	273	/* Evalute _STA to check if the device is disabled */
b8632785	274	status = acpi_evaluate_integer(mem_device->device->handle, "_STA",
4be44fcd	275	NULL, &current_status);
1da177e4	276	if (ACPI_FAILURE(status))
d550d98d	277	return -ENODEV;
1da177e4 LT	278
	279	/* Check for device status. Device should be disabled */
	280	if (current_status & ACPI_MEMORY_STA_ENABLED)
d550d98d	281	return -EINVAL;
1da177e4	282
d550d98d	283	return 0;
1da177e4 LT	284	}
1da177e4 LT	285
4be44fcd	286	static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
1da177e4 LT	287	{
1da177e4 LT	288	int result;
9ac02398	289	struct acpi_memory_info info, n;
1da177e4	290
1da177e4 LT	291
	292	/*
	293	* Ask the VM to offline this memory range.
	294	* Note: Assume that this function returns zero on success
	295	*/
9ac02398 KH	296	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
	297	if (info->enabled) {
	298	result = remove_memory(info->start_addr, info->length);
	299	if (result)
	300	return result;
	301	}
	302	kfree(info);
1da177e4 LT	303	}
	304
	305	/* Power-off and eject the device */
	306	result = acpi_memory_powerdown_device(mem_device);
	307	if (result) {
1da177e4 LT	308	/* Set the status of the device to invalid */
	309	mem_device->state = MEMORY_INVALID_STATE;
	310	return result;
	311	}
	312
	313	mem_device->state = MEMORY_POWER_OFF_STATE;
	314	return result;
	315	}
	316
4be44fcd	317	static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
1da177e4 LT	318	{
	319	struct acpi_memory_device *mem_device;
	320	struct acpi_device *device;
	321
1da177e4 LT	322
	323	switch (event) {
	324	case ACPI_NOTIFY_BUS_CHECK:
	325	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	326	"\nReceived BUS CHECK notification for device\n"));
1da177e4 LT	327	/* Fall Through */
	328	case ACPI_NOTIFY_DEVICE_CHECK:
	329	if (event == ACPI_NOTIFY_DEVICE_CHECK)
	330	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	331	"\nReceived DEVICE CHECK notification for device\n"));
1da177e4	332	if (acpi_memory_get_device(handle, &mem_device)) {
6468463a	333	printk(KERN_ERR PREFIX "Cannot find driver data\n");
d550d98d	334	return;
1da177e4 LT	335	}
	336
	337	if (!acpi_memory_check_device(mem_device)) {
	338	if (acpi_memory_enable_device(mem_device))
6468463a LB	339	printk(KERN_ERR PREFIX
6468463a LB	340	"Cannot enable memory device\n");
1da177e4 LT	341	}
	342	break;
	343	case ACPI_NOTIFY_EJECT_REQUEST:
	344	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	345	"\nReceived EJECT REQUEST notification for device\n"));
1da177e4 LT	346
1da177e4 LT	347	if (acpi_bus_get_device(handle, &device)) {
6468463a	348	printk(KERN_ERR PREFIX "Device doesn't exist\n");
1da177e4 LT	349	break;
	350	}
	351	mem_device = acpi_driver_data(device);
	352	if (!mem_device) {
6468463a	353	printk(KERN_ERR PREFIX "Driver Data is NULL\n");
1da177e4 LT	354	break;
	355	}
	356
	357	/*
	358	* Currently disabling memory device from kernel mode
	359	* TBD: Can also be disabled from user mode scripts
	360	* TBD: Can also be disabled by Callback registration
4be44fcd	361	* with generic sysfs driver
1da177e4 LT	362	*/
1da177e4 LT	363	if (acpi_memory_disable_device(mem_device))
6468463a LB	364	printk(KERN_ERR PREFIX
6468463a LB	365	"Disable memory device\n");
1da177e4 LT	366	/*
	367	* TBD: Invoke acpi_bus_remove to cleanup data structures
	368	*/
	369	break;
	370	default:
	371	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	372	"Unsupported event [0x%x]\n", event));
1da177e4 LT	373	break;
	374	}
	375
d550d98d	376	return;
1da177e4 LT	377	}
1da177e4 LT	378
4be44fcd	379	static int acpi_memory_device_add(struct acpi_device *device)
1da177e4 LT	380	{
	381	int result;
	382	struct acpi_memory_device *mem_device = NULL;
	383
1da177e4 LT	384
1da177e4 LT	385	if (!device)
d550d98d	386	return -EINVAL;
1da177e4 LT	387
	388	mem_device = kmalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
	389	if (!mem_device)
d550d98d	390	return -ENOMEM;
1da177e4 LT	391	memset(mem_device, 0, sizeof(struct acpi_memory_device));
1da177e4 LT	392
9ac02398	393	INIT_LIST_HEAD(&mem_device->res_list);
3b74863d	394	mem_device->device = device;
1da177e4 LT	395	sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
	396	sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
	397	acpi_driver_data(device) = mem_device;
	398
	399	/* Get the range from the _CRS */
	400	result = acpi_memory_get_device_resources(mem_device);
	401	if (result) {
	402	kfree(mem_device);
d550d98d	403	return result;
1da177e4 LT	404	}
	405
	406	/* Set the device state */
	407	mem_device->state = MEMORY_POWER_ON_STATE;
	408
	409	printk(KERN_INFO "%s \n", acpi_device_name(device));
	410
d550d98d	411	return result;
1da177e4 LT	412	}
1da177e4 LT	413
4be44fcd	414	static int acpi_memory_device_remove(struct acpi_device *device, int type)
1da177e4 LT	415	{
	416	struct acpi_memory_device *mem_device = NULL;
	417
1da177e4 LT	418
1da177e4 LT	419	if (!device \|\| !acpi_driver_data(device))
d550d98d	420	return -EINVAL;
1da177e4	421
4be44fcd	422	mem_device = (struct acpi_memory_device *)acpi_driver_data(device);
1da177e4 LT	423	kfree(mem_device);
1da177e4 LT	424
d550d98d	425	return 0;
1da177e4 LT	426	}
1da177e4 LT	427
1f425994 YG	428	static int acpi_memory_device_start (struct acpi_device *device)
	429	{
	430	struct acpi_memory_device *mem_device;
	431	int result = 0;
	432
1f425994 YG	433	mem_device = acpi_driver_data(device);
	434
	435	if (!acpi_memory_check_device(mem_device)) {
	436	/* call add_memory func */
	437	result = acpi_memory_enable_device(mem_device);
	438	if (result)
	439	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
	440	"Error in acpi_memory_enable_device\n"));
	441	}
d120cfb5	442	return result;
1f425994 YG	443	}
1f425994 YG	444
1da177e4 LT	445	/*
	446	* Helper function to check for memory device
	447	*/
4be44fcd	448	static acpi_status is_memory_device(acpi_handle handle)
1da177e4 LT	449	{
	450	char *hardware_id;
	451	acpi_status status;
4be44fcd	452	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1da177e4 LT	453	struct acpi_device_info *info;
1da177e4 LT	454
1da177e4 LT	455
	456	status = acpi_get_object_info(handle, &buffer);
	457	if (ACPI_FAILURE(status))
d550d98d	458	return status;
1da177e4 LT	459
	460	info = buffer.pointer;
	461	if (!(info->valid & ACPI_VALID_HID)) {
02438d87	462	kfree(buffer.pointer);
d550d98d	463	return AE_ERROR;
1da177e4 LT	464	}
	465
	466	hardware_id = info->hardware_id.value;
	467	if ((hardware_id == NULL) \|\|
4be44fcd	468	(strcmp(hardware_id, ACPI_MEMORY_DEVICE_HID)))
1da177e4 LT	469	status = AE_ERROR;
1da177e4 LT	470
02438d87	471	kfree(buffer.pointer);
d550d98d	472	return status;
1da177e4 LT	473	}
	474
	475	static acpi_status
4be44fcd LB	476	acpi_memory_register_notify_handler(acpi_handle handle,
4be44fcd LB	477	u32 level, void ctxt, void *retv)
1da177e4 LT	478	{
	479	acpi_status status;
	480
1da177e4 LT	481
1da177e4 LT	482	status = is_memory_device(handle);
a6fc6720 TR	483	if (ACPI_FAILURE(status)){
a6fc6720 TR	484	ACPI_EXCEPTION((AE_INFO, status, "handle is no memory device"));
d550d98d	485	return AE_OK; /* continue */
a6fc6720	486	}
1da177e4 LT	487
1da177e4 LT	488	status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
4be44fcd	489	acpi_memory_device_notify, NULL);
a6fc6720	490	/* continue */
d550d98d	491	return AE_OK;
1da177e4 LT	492	}
	493
	494	static acpi_status
4be44fcd LB	495	acpi_memory_deregister_notify_handler(acpi_handle handle,
4be44fcd LB	496	u32 level, void ctxt, void *retv)
1da177e4 LT	497	{
	498	acpi_status status;
	499
1da177e4 LT	500
1da177e4 LT	501	status = is_memory_device(handle);
a6fc6720 TR	502	if (ACPI_FAILURE(status)){
a6fc6720 TR	503	ACPI_EXCEPTION((AE_INFO, status, "handle is no memory device"));
d550d98d	504	return AE_OK; /* continue */
a6fc6720	505	}
1da177e4 LT	506
1da177e4 LT	507	status = acpi_remove_notify_handler(handle,
4be44fcd LB	508	ACPI_SYSTEM_NOTIFY,
4be44fcd LB	509	acpi_memory_device_notify);
1da177e4	510
d550d98d	511	return AE_OK; /* continue */
1da177e4 LT	512	}
1da177e4 LT	513
4be44fcd	514	static int __init acpi_memory_device_init(void)
1da177e4 LT	515	{
	516	int result;
	517	acpi_status status;
	518
1da177e4 LT	519
	520	result = acpi_bus_register_driver(&acpi_memory_device_driver);
	521
	522	if (result < 0)
d550d98d	523	return -ENODEV;
1da177e4 LT	524
1da177e4 LT	525	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
4be44fcd LB	526	ACPI_UINT32_MAX,
	527	acpi_memory_register_notify_handler,
	528	NULL, NULL);
1da177e4	529
4be44fcd	530	if (ACPI_FAILURE(status)) {
a6fc6720	531	ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
1da177e4	532	acpi_bus_unregister_driver(&acpi_memory_device_driver);
d550d98d	533	return -ENODEV;
4be44fcd	534	}
1da177e4	535
d550d98d	536	return 0;
1da177e4 LT	537	}
1da177e4 LT	538
4be44fcd	539	static void __exit acpi_memory_device_exit(void)
1da177e4 LT	540	{
	541	acpi_status status;
	542
1da177e4 LT	543
	544	/*
	545	* Adding this to un-install notification handlers for all the device
	546	* handles.
	547	*/
	548	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
4be44fcd LB	549	ACPI_UINT32_MAX,
	550	acpi_memory_deregister_notify_handler,
	551	NULL, NULL);
1da177e4	552
4be44fcd	553	if (ACPI_FAILURE(status))
a6fc6720	554	ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
1da177e4 LT	555
	556	acpi_bus_unregister_driver(&acpi_memory_device_driver);
	557
d550d98d	558	return;
1da177e4 LT	559	}
	560
	561	module_init(acpi_memory_device_init);
	562	module_exit(acpi_memory_device_exit);