[deliverable/linux.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 {
	acpi_handle handle;
	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->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->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->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) {
		u64 start_pfn, end_pfn;

		start_pfn = info->start_addr >> PAGE_SHIFT;
		end_pfn = (info->start_addr + info->length - 1) >> PAGE_SHIFT;

		if (pfn_valid(start_pfn) || pfn_valid(end_pfn)) {
			/* already enabled. try next area */
			num_enabled++;
			continue;
		}

		result = add_memory(node, info->start_addr, info->length);
		if (result)
			continue;
		info->enabled = 1;
		num_enabled++;
	}
	if (!num_enabled) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "\nadd_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->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->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->handle = device->handle;
	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)) {
		acpi_os_free(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;

	acpi_os_free(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 LT	82	struct acpi_memory_device {
1da177e4 LT	83	acpi_handle handle;
3b74863d	84	struct acpi_device * device;
4be44fcd	85	unsigned int state; /* State of the memory device */
9ac02398	86	struct list_head res_list;
1da177e4 LT	87	};
1da177e4 LT	88
9ac02398 KH	89	static acpi_status
	90	acpi_memory_get_resource(struct acpi_resource resource, void context)
	91	{
	92	struct acpi_memory_device *mem_device = context;
	93	struct acpi_resource_address64 address64;
	94	struct acpi_memory_info info, new;
	95	acpi_status status;
	96
	97	status = acpi_resource_to_address64(resource, &address64);
	98	if (ACPI_FAILURE(status) \|\|
	99	(address64.resource_type != ACPI_MEMORY_RANGE))
	100	return AE_OK;
	101
	102	list_for_each_entry(info, &mem_device->res_list, list) {
	103	/* Can we combine the resource range information? */
	104	if ((info->caching == address64.info.mem.caching) &&
	105	(info->write_protect == address64.info.mem.write_protect) &&
	106	(info->start_addr + info->length == address64.minimum)) {
	107	info->length += address64.address_length;
	108	return AE_OK;
	109	}
	110	}
	111
	112	new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL);
	113	if (!new)
	114	return AE_ERROR;
	115
	116	INIT_LIST_HEAD(&new->list);
	117	new->caching = address64.info.mem.caching;
	118	new->write_protect = address64.info.mem.write_protect;
	119	new->start_addr = address64.minimum;
	120	new->length = address64.address_length;
	121	list_add_tail(&new->list, &mem_device->res_list);
	122
	123	return AE_OK;
	124	}
	125
1da177e4 LT	126	static int
	127	acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
	128	{
	129	acpi_status status;
9ac02398	130	struct acpi_memory_info info, n;
1da177e4	131
1da177e4	132
9ac02398 KH	133	status = acpi_walk_resources(mem_device->handle, METHOD_NAME__CRS,
	134	acpi_memory_get_resource, mem_device);
	135	if (ACPI_FAILURE(status)) {
	136	list_for_each_entry_safe(info, n, &mem_device->res_list, list)
	137	kfree(info);
d550d98d	138	return -EINVAL;
1da177e4 LT	139	}
1da177e4 LT	140
d550d98d	141	return 0;
1da177e4 LT	142	}
	143
	144	static int
	145	acpi_memory_get_device(acpi_handle handle,
4be44fcd	146	struct acpi_memory_device **mem_device)
1da177e4 LT	147	{
	148	acpi_status status;
	149	acpi_handle phandle;
	150	struct acpi_device *device = NULL;
	151	struct acpi_device *pdevice = NULL;
	152
1da177e4 LT	153
	154	if (!acpi_bus_get_device(handle, &device) && device)
	155	goto end;
	156
	157	status = acpi_get_parent(handle, &phandle);
	158	if (ACPI_FAILURE(status)) {
a6fc6720	159	ACPI_EXCEPTION((AE_INFO, status, "Cannot find acpi parent"));
d550d98d	160	return -EINVAL;
1da177e4 LT	161	}
	162
	163	/* Get the parent device */
	164	status = acpi_bus_get_device(phandle, &pdevice);
	165	if (ACPI_FAILURE(status)) {
a6fc6720	166	ACPI_EXCEPTION((AE_INFO, status, "Cannot get acpi bus device"));
d550d98d	167	return -EINVAL;
1da177e4 LT	168	}
	169
	170	/*
	171	* Now add the notified device. This creates the acpi_device
	172	* and invokes .add function
	173	*/
	174	status = acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE);
	175	if (ACPI_FAILURE(status)) {
a6fc6720	176	ACPI_EXCEPTION((AE_INFO, status, "Cannot add acpi bus"));
d550d98d	177	return -EINVAL;
1da177e4 LT	178	}
1da177e4 LT	179
4be44fcd	180	end:
1da177e4 LT	181	*mem_device = acpi_driver_data(device);
1da177e4 LT	182	if (!(*mem_device)) {
4be44fcd	183	printk(KERN_ERR "\n driver data not found");
d550d98d	184	return -ENODEV;
1da177e4 LT	185	}
1da177e4 LT	186
d550d98d	187	return 0;
1da177e4 LT	188	}
1da177e4 LT	189
4be44fcd	190	static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
1da177e4 LT	191	{
	192	unsigned long current_status;
	193
1da177e4 LT	194
	195	/* Get device present/absent information from the _STA */
	196	if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->handle, "_STA",
4be44fcd	197	NULL, &current_status)))
d550d98d	198	return -ENODEV;
1da177e4 LT	199	/*
	200	* Check for device status. Device should be
	201	* present/enabled/functioning.
	202	*/
	203	if (!((current_status & ACPI_MEMORY_STA_PRESENT)
4be44fcd LB	204	&& (current_status & ACPI_MEMORY_STA_ENABLED)
4be44fcd LB	205	&& (current_status & ACPI_MEMORY_STA_FUNCTIONAL)))
d550d98d	206	return -ENODEV;
1da177e4	207
d550d98d	208	return 0;
1da177e4 LT	209	}
1da177e4 LT	210
4be44fcd	211	static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
1da177e4	212	{
9ac02398 KH	213	int result, num_enabled = 0;
9ac02398 KH	214	struct acpi_memory_info *info;
1e3590e2	215	int node;
1da177e4	216
1da177e4 LT	217
	218	/* Get the range from the _CRS */
	219	result = acpi_memory_get_device_resources(mem_device);
	220	if (result) {
6468463a	221	printk(KERN_ERR PREFIX "get_device_resources failed\n");
1da177e4 LT	222	mem_device->state = MEMORY_INVALID_STATE;
	223	return result;
	224	}
	225
1e3590e2	226	node = acpi_get_node(mem_device->handle);
1da177e4 LT	227	/*
	228	* Tell the VM there is more memory here...
	229	* Note: Assume that this function returns zero on success
9ac02398 KH	230	* We don't have memory-hot-add rollback function,now.
9ac02398 KH	231	* (i.e. memory-hot-remove function)
1da177e4	232	*/
9ac02398	233	list_for_each_entry(info, &mem_device->res_list, list) {
dd56a8e3 YG	234	u64 start_pfn, end_pfn;
	235
	236	start_pfn = info->start_addr >> PAGE_SHIFT;
	237	end_pfn = (info->start_addr + info->length - 1) >> PAGE_SHIFT;
	238
	239	if (pfn_valid(start_pfn) \|\| pfn_valid(end_pfn)) {
	240	/* already enabled. try next area */
	241	num_enabled++;
	242	continue;
	243	}
	244
bc02af93	245	result = add_memory(node, info->start_addr, info->length);
9ac02398 KH	246	if (result)
	247	continue;
	248	info->enabled = 1;
	249	num_enabled++;
	250	}
	251	if (!num_enabled) {
4be44fcd	252	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "\nadd_memory failed\n"));
1da177e4	253	mem_device->state = MEMORY_INVALID_STATE;
9ac02398	254	return -EINVAL;
1da177e4 LT	255	}
	256
	257	return result;
	258	}
	259
4be44fcd	260	static int acpi_memory_powerdown_device(struct acpi_memory_device *mem_device)
1da177e4 LT	261	{
1da177e4 LT	262	acpi_status status;
4be44fcd	263	struct acpi_object_list arg_list;
1da177e4 LT	264	union acpi_object arg;
	265	unsigned long current_status;
	266
1da177e4 LT	267
	268	/* Issue the _EJ0 command */
	269	arg_list.count = 1;
	270	arg_list.pointer = &arg;
	271	arg.type = ACPI_TYPE_INTEGER;
	272	arg.integer.value = 1;
	273	status = acpi_evaluate_object(mem_device->handle,
4be44fcd	274	"_EJ0", &arg_list, NULL);
1da177e4 LT	275	/* Return on _EJ0 failure */
1da177e4 LT	276	if (ACPI_FAILURE(status)) {
a6fc6720	277	ACPI_EXCEPTION((AE_INFO, status, "_EJ0 failed"));
d550d98d	278	return -ENODEV;
1da177e4 LT	279	}
	280
	281	/* Evalute _STA to check if the device is disabled */
	282	status = acpi_evaluate_integer(mem_device->handle, "_STA",
4be44fcd	283	NULL, &current_status);
1da177e4	284	if (ACPI_FAILURE(status))
d550d98d	285	return -ENODEV;
1da177e4 LT	286
	287	/* Check for device status. Device should be disabled */
	288	if (current_status & ACPI_MEMORY_STA_ENABLED)
d550d98d	289	return -EINVAL;
1da177e4	290
d550d98d	291	return 0;
1da177e4 LT	292	}
1da177e4 LT	293
4be44fcd	294	static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
1da177e4 LT	295	{
1da177e4 LT	296	int result;
9ac02398	297	struct acpi_memory_info info, n;
1da177e4	298
1da177e4 LT	299
	300	/*
	301	* Ask the VM to offline this memory range.
	302	* Note: Assume that this function returns zero on success
	303	*/
9ac02398 KH	304	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
	305	if (info->enabled) {
	306	result = remove_memory(info->start_addr, info->length);
	307	if (result)
	308	return result;
	309	}
	310	kfree(info);
1da177e4 LT	311	}
	312
	313	/* Power-off and eject the device */
	314	result = acpi_memory_powerdown_device(mem_device);
	315	if (result) {
1da177e4 LT	316	/* Set the status of the device to invalid */
	317	mem_device->state = MEMORY_INVALID_STATE;
	318	return result;
	319	}
	320
	321	mem_device->state = MEMORY_POWER_OFF_STATE;
	322	return result;
	323	}
	324
4be44fcd	325	static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
1da177e4 LT	326	{
	327	struct acpi_memory_device *mem_device;
	328	struct acpi_device *device;
	329
1da177e4 LT	330
	331	switch (event) {
	332	case ACPI_NOTIFY_BUS_CHECK:
	333	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	334	"\nReceived BUS CHECK notification for device\n"));
1da177e4 LT	335	/* Fall Through */
	336	case ACPI_NOTIFY_DEVICE_CHECK:
	337	if (event == ACPI_NOTIFY_DEVICE_CHECK)
	338	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	339	"\nReceived DEVICE CHECK notification for device\n"));
1da177e4	340	if (acpi_memory_get_device(handle, &mem_device)) {
6468463a	341	printk(KERN_ERR PREFIX "Cannot find driver data\n");
d550d98d	342	return;
1da177e4 LT	343	}
	344
	345	if (!acpi_memory_check_device(mem_device)) {
	346	if (acpi_memory_enable_device(mem_device))
6468463a LB	347	printk(KERN_ERR PREFIX
6468463a LB	348	"Cannot enable memory device\n");
1da177e4 LT	349	}
	350	break;
	351	case ACPI_NOTIFY_EJECT_REQUEST:
	352	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	353	"\nReceived EJECT REQUEST notification for device\n"));
1da177e4 LT	354
1da177e4 LT	355	if (acpi_bus_get_device(handle, &device)) {
6468463a	356	printk(KERN_ERR PREFIX "Device doesn't exist\n");
1da177e4 LT	357	break;
	358	}
	359	mem_device = acpi_driver_data(device);
	360	if (!mem_device) {
6468463a	361	printk(KERN_ERR PREFIX "Driver Data is NULL\n");
1da177e4 LT	362	break;
	363	}
	364
	365	/*
	366	* Currently disabling memory device from kernel mode
	367	* TBD: Can also be disabled from user mode scripts
	368	* TBD: Can also be disabled by Callback registration
4be44fcd	369	* with generic sysfs driver
1da177e4 LT	370	*/
1da177e4 LT	371	if (acpi_memory_disable_device(mem_device))
6468463a LB	372	printk(KERN_ERR PREFIX
6468463a LB	373	"Disable memory device\n");
1da177e4 LT	374	/*
	375	* TBD: Invoke acpi_bus_remove to cleanup data structures
	376	*/
	377	break;
	378	default:
	379	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	380	"Unsupported event [0x%x]\n", event));
1da177e4 LT	381	break;
	382	}
	383
d550d98d	384	return;
1da177e4 LT	385	}
1da177e4 LT	386
4be44fcd	387	static int acpi_memory_device_add(struct acpi_device *device)
1da177e4 LT	388	{
	389	int result;
	390	struct acpi_memory_device *mem_device = NULL;
	391
1da177e4 LT	392
1da177e4 LT	393	if (!device)
d550d98d	394	return -EINVAL;
1da177e4 LT	395
	396	mem_device = kmalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
	397	if (!mem_device)
d550d98d	398	return -ENOMEM;
1da177e4 LT	399	memset(mem_device, 0, sizeof(struct acpi_memory_device));
1da177e4 LT	400
9ac02398	401	INIT_LIST_HEAD(&mem_device->res_list);
1da177e4	402	mem_device->handle = device->handle;
3b74863d	403	mem_device->device = device;
1da177e4 LT	404	sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
	405	sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
	406	acpi_driver_data(device) = mem_device;
	407
	408	/* Get the range from the _CRS */
	409	result = acpi_memory_get_device_resources(mem_device);
	410	if (result) {
	411	kfree(mem_device);
d550d98d	412	return result;
1da177e4 LT	413	}
	414
	415	/* Set the device state */
	416	mem_device->state = MEMORY_POWER_ON_STATE;
	417
	418	printk(KERN_INFO "%s \n", acpi_device_name(device));
	419
d550d98d	420	return result;
1da177e4 LT	421	}
1da177e4 LT	422
4be44fcd	423	static int acpi_memory_device_remove(struct acpi_device *device, int type)
1da177e4 LT	424	{
	425	struct acpi_memory_device *mem_device = NULL;
	426
1da177e4 LT	427
1da177e4 LT	428	if (!device \|\| !acpi_driver_data(device))
d550d98d	429	return -EINVAL;
1da177e4	430
4be44fcd	431	mem_device = (struct acpi_memory_device *)acpi_driver_data(device);
1da177e4 LT	432	kfree(mem_device);
1da177e4 LT	433
d550d98d	434	return 0;
1da177e4 LT	435	}
1da177e4 LT	436
1f425994 YG	437	static int acpi_memory_device_start (struct acpi_device *device)
	438	{
	439	struct acpi_memory_device *mem_device;
	440	int result = 0;
	441
1f425994 YG	442	mem_device = acpi_driver_data(device);
	443
	444	if (!acpi_memory_check_device(mem_device)) {
	445	/* call add_memory func */
	446	result = acpi_memory_enable_device(mem_device);
	447	if (result)
	448	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
	449	"Error in acpi_memory_enable_device\n"));
	450	}
d120cfb5	451	return result;
1f425994 YG	452	}
1f425994 YG	453
1da177e4 LT	454	/*
	455	* Helper function to check for memory device
	456	*/
4be44fcd	457	static acpi_status is_memory_device(acpi_handle handle)
1da177e4 LT	458	{
	459	char *hardware_id;
	460	acpi_status status;
4be44fcd	461	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1da177e4 LT	462	struct acpi_device_info *info;
1da177e4 LT	463
1da177e4 LT	464
	465	status = acpi_get_object_info(handle, &buffer);
	466	if (ACPI_FAILURE(status))
d550d98d	467	return status;
1da177e4 LT	468
	469	info = buffer.pointer;
	470	if (!(info->valid & ACPI_VALID_HID)) {
	471	acpi_os_free(buffer.pointer);
d550d98d	472	return AE_ERROR;
1da177e4 LT	473	}
	474
	475	hardware_id = info->hardware_id.value;
	476	if ((hardware_id == NULL) \|\|
4be44fcd	477	(strcmp(hardware_id, ACPI_MEMORY_DEVICE_HID)))
1da177e4 LT	478	status = AE_ERROR;
	479
	480	acpi_os_free(buffer.pointer);
d550d98d	481	return status;
1da177e4 LT	482	}
	483
	484	static acpi_status
4be44fcd LB	485	acpi_memory_register_notify_handler(acpi_handle handle,
4be44fcd LB	486	u32 level, void ctxt, void *retv)
1da177e4 LT	487	{
	488	acpi_status status;
	489
1da177e4 LT	490
1da177e4 LT	491	status = is_memory_device(handle);
a6fc6720 TR	492	if (ACPI_FAILURE(status)){
a6fc6720 TR	493	ACPI_EXCEPTION((AE_INFO, status, "handle is no memory device"));
d550d98d	494	return AE_OK; /* continue */
a6fc6720	495	}
1da177e4 LT	496
1da177e4 LT	497	status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
4be44fcd	498	acpi_memory_device_notify, NULL);
a6fc6720	499	/* continue */
d550d98d	500	return AE_OK;
1da177e4 LT	501	}
	502
	503	static acpi_status
4be44fcd LB	504	acpi_memory_deregister_notify_handler(acpi_handle handle,
4be44fcd LB	505	u32 level, void ctxt, void *retv)
1da177e4 LT	506	{
	507	acpi_status status;
	508
1da177e4 LT	509
1da177e4 LT	510	status = is_memory_device(handle);
a6fc6720 TR	511	if (ACPI_FAILURE(status)){
a6fc6720 TR	512	ACPI_EXCEPTION((AE_INFO, status, "handle is no memory device"));
d550d98d	513	return AE_OK; /* continue */
a6fc6720	514	}
1da177e4 LT	515
1da177e4 LT	516	status = acpi_remove_notify_handler(handle,
4be44fcd LB	517	ACPI_SYSTEM_NOTIFY,
4be44fcd LB	518	acpi_memory_device_notify);
1da177e4	519
d550d98d	520	return AE_OK; /* continue */
1da177e4 LT	521	}
1da177e4 LT	522
4be44fcd	523	static int __init acpi_memory_device_init(void)
1da177e4 LT	524	{
	525	int result;
	526	acpi_status status;
	527
1da177e4 LT	528
	529	result = acpi_bus_register_driver(&acpi_memory_device_driver);
	530
	531	if (result < 0)
d550d98d	532	return -ENODEV;
1da177e4 LT	533
1da177e4 LT	534	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
4be44fcd LB	535	ACPI_UINT32_MAX,
	536	acpi_memory_register_notify_handler,
	537	NULL, NULL);
1da177e4	538
4be44fcd	539	if (ACPI_FAILURE(status)) {
a6fc6720	540	ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
1da177e4	541	acpi_bus_unregister_driver(&acpi_memory_device_driver);
d550d98d	542	return -ENODEV;
4be44fcd	543	}
1da177e4	544
d550d98d	545	return 0;
1da177e4 LT	546	}
1da177e4 LT	547
4be44fcd	548	static void __exit acpi_memory_device_exit(void)
1da177e4 LT	549	{
	550	acpi_status status;
	551
1da177e4 LT	552
	553	/*
	554	* Adding this to un-install notification handlers for all the device
	555	* handles.
	556	*/
	557	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
4be44fcd LB	558	ACPI_UINT32_MAX,
	559	acpi_memory_deregister_notify_handler,
	560	NULL, NULL);
1da177e4	561
4be44fcd	562	if (ACPI_FAILURE(status))
a6fc6720	563	ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
1da177e4 LT	564
	565	acpi_bus_unregister_driver(&acpi_memory_device_driver);
	566
d550d98d	567	return;
1da177e4 LT	568	}
	569
	570	module_init(acpi_memory_device_init);
	571	module_exit(acpi_memory_device_exit);