[linux-2.6-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 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,
		},
};

struct acpi_memory_device {
	acpi_handle handle;
	unsigned int state;	/* State of the memory device */
	unsigned short caching;	/* memory cache attribute */
	unsigned short write_protect;	/* memory read/write attribute */
	u64 start_addr;		/* Memory Range start physical addr */
	u64 end_addr;		/* Memory Range end physical addr */
};

static int
acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
{
	acpi_status status;
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	struct acpi_resource *resource = NULL;
	struct acpi_resource_address64 address64;

	ACPI_FUNCTION_TRACE("acpi_memory_get_device_resources");

	/* Get the range from the _CRS */
	status = acpi_get_current_resources(mem_device->handle, &buffer);
	if (ACPI_FAILURE(status))
		return_VALUE(-EINVAL);

	resource = (struct acpi_resource *)buffer.pointer;
	status = acpi_resource_to_address64(resource, &address64);
	if (ACPI_SUCCESS(status)) {
		if (address64.resource_type == ACPI_MEMORY_RANGE) {
			/* Populate the structure */
			mem_device->caching =
			    address64.info.mem.caching;
			mem_device->write_protect =
			    address64.info.mem.write_protect;
			mem_device->start_addr = address64.minimum;
			mem_device->end_addr = address64.maximum;
		}
	}

	acpi_os_free(buffer.pointer);
	return_VALUE(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;

	ACPI_FUNCTION_TRACE("acpi_memory_get_device");

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

	status = acpi_get_parent(handle, &phandle);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error in acpi_get_parent\n"));
		return_VALUE(-EINVAL);
	}

	/* Get the parent device */
	status = acpi_bus_get_device(phandle, &pdevice);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
				  "Error in acpi_bus_get_device\n"));
		return_VALUE(-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_DEBUG_PRINT((ACPI_DB_ERROR, "Error in acpi_bus_add\n"));
		return_VALUE(-EINVAL);
	}

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

	return_VALUE(0);
}

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

	ACPI_FUNCTION_TRACE("acpi_memory_check_device");

	/* Get device present/absent information from the _STA */
	if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->handle, "_STA",
					       NULL, &current_status)))
		return_VALUE(-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_VALUE(-ENODEV);

	return_VALUE(0);
}

static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
{
	int result;

	ACPI_FUNCTION_TRACE("acpi_memory_enable_device");

	/* Get the range from the _CRS */
	result = acpi_memory_get_device_resources(mem_device);
	if (result) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
				  "\nget_device_resources failed\n"));
		mem_device->state = MEMORY_INVALID_STATE;
		return result;
	}

	/*
	 * Tell the VM there is more memory here...
	 * Note: Assume that this function returns zero on success
	 */
	result = add_memory(mem_device->start_addr,
			    (mem_device->end_addr - mem_device->start_addr) + 1);
	if (result) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "\nadd_memory failed\n"));
		mem_device->state = MEMORY_INVALID_STATE;
		return result;
	}

	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;

	ACPI_FUNCTION_TRACE("acpi_memory_powerdown_device");

	/* 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_DEBUG_PRINT((ACPI_DB_ERROR, "_EJ0 failed.\n"));
		return_VALUE(-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_VALUE(-ENODEV);

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

	return_VALUE(0);
}

static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
{
	int result;
	u64 start = mem_device->start_addr;
	u64 len = mem_device->end_addr - start + 1;

	ACPI_FUNCTION_TRACE("acpi_memory_disable_device");

	/*
	 * Ask the VM to offline this memory range.
	 * Note: Assume that this function returns zero on success
	 */
	result = remove_memory(start, len);
	if (result) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Hot-Remove failed.\n"));
		return_VALUE(result);
	}

	/* Power-off and eject the device */
	result = acpi_memory_powerdown_device(mem_device);
	if (result) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
				  "Device Power Down failed.\n"));
		/* 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;

	ACPI_FUNCTION_TRACE("acpi_memory_device_notify");

	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)) {
			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
					  "Error in finding driver data\n"));
			return_VOID;
		}

		if (!acpi_memory_check_device(mem_device)) {
			if (acpi_memory_enable_device(mem_device))
				ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
						  "Error in acpi_memory_enable_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)) {
			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
					  "Device doesn't exist\n"));
			break;
		}
		mem_device = acpi_driver_data(device);
		if (!mem_device) {
			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
					  "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))
			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
					  "Error in acpi_memory_disable_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_VOID;
}

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

	ACPI_FUNCTION_TRACE("acpi_memory_device_add");

	if (!device)
		return_VALUE(-EINVAL);

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

	mem_device->handle = device->handle;
	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_VALUE(result);
	}

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

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

	return_VALUE(result);
}

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

	ACPI_FUNCTION_TRACE("acpi_memory_device_remove");

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

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

	return_VALUE(0);
}

/*
 * 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;

	ACPI_FUNCTION_TRACE("is_memory_device");

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

	info = buffer.pointer;
	if (!(info->valid & ACPI_VALID_HID)) {
		acpi_os_free(buffer.pointer);
		return_ACPI_STATUS(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_ACPI_STATUS(status);
}

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

	ACPI_FUNCTION_TRACE("acpi_memory_register_notify_handler");

	status = is_memory_device(handle);
	if (ACPI_FAILURE(status))
		return_ACPI_STATUS(AE_OK);	/* continue */

	status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
					     acpi_memory_device_notify, NULL);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
				  "Error installing notify handler\n"));
		return_ACPI_STATUS(AE_OK);	/* continue */
	}

	return_ACPI_STATUS(status);
}

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

	ACPI_FUNCTION_TRACE("acpi_memory_deregister_notify_handler");

	status = is_memory_device(handle);
	if (ACPI_FAILURE(status))
		return_ACPI_STATUS(AE_OK);	/* continue */

	status = acpi_remove_notify_handler(handle,
					    ACPI_SYSTEM_NOTIFY,
					    acpi_memory_device_notify);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
				  "Error removing notify handler\n"));
		return_ACPI_STATUS(AE_OK);	/* continue */
	}

	return_ACPI_STATUS(status);
}

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

	ACPI_FUNCTION_TRACE("acpi_memory_device_init");

	result = acpi_bus_register_driver(&acpi_memory_device_driver);

	if (result < 0)
		return_VALUE(-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_DEBUG_PRINT((ACPI_DB_ERROR, "walk_namespace failed\n"));
		acpi_bus_unregister_driver(&acpi_memory_device_driver);
		return_VALUE(-ENODEV);
	}

	return_VALUE(0);
}

static void __exit acpi_memory_device_exit(void)
{
	acpi_status status;

	ACPI_FUNCTION_TRACE("acpi_memory_device_exit");

	/*
	 * 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_DEBUG_PRINT((ACPI_DB_ERROR, "walk_namespace failed\n"));

	acpi_bus_unregister_driver(&acpi_memory_device_driver);

	return_VOID;
}

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);
1da177e4 LT	60
1da177e4 LT	61	static struct acpi_driver acpi_memory_device_driver = {
4be44fcd LB	62	.name = ACPI_MEMORY_DEVICE_DRIVER_NAME,
	63	.class = ACPI_MEMORY_DEVICE_CLASS,
	64	.ids = ACPI_MEMORY_DEVICE_HID,
	65	.ops = {
	66	.add = acpi_memory_device_add,
	67	.remove = acpi_memory_device_remove,
	68	},
1da177e4 LT	69	};
	70
	71	struct acpi_memory_device {
	72	acpi_handle handle;
4be44fcd	73	unsigned int state; /* State of the memory device */
3963f008 KH	74	unsigned short caching; /* memory cache attribute */
3963f008 KH	75	unsigned short write_protect; /* memory read/write attribute */
4be44fcd LB	76	u64 start_addr; /* Memory Range start physical addr */
4be44fcd LB	77	u64 end_addr; /* Memory Range end physical addr */
1da177e4 LT	78	};
1da177e4 LT	79
1da177e4 LT	80	static int
	81	acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
	82	{
	83	acpi_status status;
4be44fcd	84	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1da177e4 LT	85	struct acpi_resource *resource = NULL;
	86	struct acpi_resource_address64 address64;
	87
	88	ACPI_FUNCTION_TRACE("acpi_memory_get_device_resources");
	89
	90	/* Get the range from the _CRS */
	91	status = acpi_get_current_resources(mem_device->handle, &buffer);
	92	if (ACPI_FAILURE(status))
	93	return_VALUE(-EINVAL);
	94
4be44fcd	95	resource = (struct acpi_resource *)buffer.pointer;
1da177e4 LT	96	status = acpi_resource_to_address64(resource, &address64);
	97	if (ACPI_SUCCESS(status)) {
	98	if (address64.resource_type == ACPI_MEMORY_RANGE) {
	99	/* Populate the structure */
3963f008 KH	100	mem_device->caching =
	101	address64.info.mem.caching;
	102	mem_device->write_protect =
	103	address64.info.mem.write_protect;
50eca3eb BM	104	mem_device->start_addr = address64.minimum;
50eca3eb BM	105	mem_device->end_addr = address64.maximum;
1da177e4 LT	106	}
	107	}
	108
	109	acpi_os_free(buffer.pointer);
	110	return_VALUE(0);
	111	}
	112
	113	static int
	114	acpi_memory_get_device(acpi_handle handle,
4be44fcd	115	struct acpi_memory_device **mem_device)
1da177e4 LT	116	{
	117	acpi_status status;
	118	acpi_handle phandle;
	119	struct acpi_device *device = NULL;
	120	struct acpi_device *pdevice = NULL;
	121
	122	ACPI_FUNCTION_TRACE("acpi_memory_get_device");
	123
	124	if (!acpi_bus_get_device(handle, &device) && device)
	125	goto end;
	126
	127	status = acpi_get_parent(handle, &phandle);
	128	if (ACPI_FAILURE(status)) {
4be44fcd	129	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error in acpi_get_parent\n"));
1da177e4 LT	130	return_VALUE(-EINVAL);
	131	}
	132
	133	/* Get the parent device */
	134	status = acpi_bus_get_device(phandle, &pdevice);
	135	if (ACPI_FAILURE(status)) {
	136	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	137	"Error in acpi_bus_get_device\n"));
1da177e4 LT	138	return_VALUE(-EINVAL);
	139	}
	140
	141	/*
	142	* Now add the notified device. This creates the acpi_device
	143	* and invokes .add function
	144	*/
	145	status = acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE);
	146	if (ACPI_FAILURE(status)) {
4be44fcd	147	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error in acpi_bus_add\n"));
1da177e4 LT	148	return_VALUE(-EINVAL);
	149	}
	150
4be44fcd	151	end:
1da177e4 LT	152	*mem_device = acpi_driver_data(device);
1da177e4 LT	153	if (!(*mem_device)) {
4be44fcd	154	printk(KERN_ERR "\n driver data not found");
1da177e4 LT	155	return_VALUE(-ENODEV);
	156	}
	157
	158	return_VALUE(0);
	159	}
	160
4be44fcd	161	static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
1da177e4 LT	162	{
	163	unsigned long current_status;
	164
	165	ACPI_FUNCTION_TRACE("acpi_memory_check_device");
	166
	167	/* Get device present/absent information from the _STA */
	168	if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->handle, "_STA",
4be44fcd	169	NULL, &current_status)))
1da177e4 LT	170	return_VALUE(-ENODEV);
	171	/*
	172	* Check for device status. Device should be
	173	* present/enabled/functioning.
	174	*/
	175	if (!((current_status & ACPI_MEMORY_STA_PRESENT)
4be44fcd LB	176	&& (current_status & ACPI_MEMORY_STA_ENABLED)
4be44fcd LB	177	&& (current_status & ACPI_MEMORY_STA_FUNCTIONAL)))
1da177e4 LT	178	return_VALUE(-ENODEV);
	179
	180	return_VALUE(0);
	181	}
	182
4be44fcd	183	static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
1da177e4 LT	184	{
	185	int result;
	186
	187	ACPI_FUNCTION_TRACE("acpi_memory_enable_device");
	188
	189	/* Get the range from the _CRS */
	190	result = acpi_memory_get_device_resources(mem_device);
	191	if (result) {
	192	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	193	"\nget_device_resources failed\n"));
1da177e4 LT	194	mem_device->state = MEMORY_INVALID_STATE;
	195	return result;
	196	}
	197
	198	/*
	199	* Tell the VM there is more memory here...
	200	* Note: Assume that this function returns zero on success
	201	*/
	202	result = add_memory(mem_device->start_addr,
0b0acbec	203	(mem_device->end_addr - mem_device->start_addr) + 1);
1da177e4	204	if (result) {
4be44fcd	205	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "\nadd_memory failed\n"));
1da177e4 LT	206	mem_device->state = MEMORY_INVALID_STATE;
	207	return result;
	208	}
	209
	210	return result;
	211	}
	212
4be44fcd	213	static int acpi_memory_powerdown_device(struct acpi_memory_device *mem_device)
1da177e4 LT	214	{
1da177e4 LT	215	acpi_status status;
4be44fcd	216	struct acpi_object_list arg_list;
1da177e4 LT	217	union acpi_object arg;
	218	unsigned long current_status;
	219
	220	ACPI_FUNCTION_TRACE("acpi_memory_powerdown_device");
	221
	222	/* Issue the _EJ0 command */
	223	arg_list.count = 1;
	224	arg_list.pointer = &arg;
	225	arg.type = ACPI_TYPE_INTEGER;
	226	arg.integer.value = 1;
	227	status = acpi_evaluate_object(mem_device->handle,
4be44fcd	228	"_EJ0", &arg_list, NULL);
1da177e4 LT	229	/* Return on _EJ0 failure */
1da177e4 LT	230	if (ACPI_FAILURE(status)) {
4be44fcd	231	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "_EJ0 failed.\n"));
1da177e4 LT	232	return_VALUE(-ENODEV);
	233	}
	234
	235	/* Evalute _STA to check if the device is disabled */
	236	status = acpi_evaluate_integer(mem_device->handle, "_STA",
4be44fcd	237	NULL, &current_status);
1da177e4 LT	238	if (ACPI_FAILURE(status))
	239	return_VALUE(-ENODEV);
	240
	241	/* Check for device status. Device should be disabled */
	242	if (current_status & ACPI_MEMORY_STA_ENABLED)
	243	return_VALUE(-EINVAL);
	244
	245	return_VALUE(0);
	246	}
	247
4be44fcd	248	static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
1da177e4 LT	249	{
	250	int result;
	251	u64 start = mem_device->start_addr;
	252	u64 len = mem_device->end_addr - start + 1;
1da177e4 LT	253
	254	ACPI_FUNCTION_TRACE("acpi_memory_disable_device");
	255
	256	/*
	257	* Ask the VM to offline this memory range.
	258	* Note: Assume that this function returns zero on success
	259	*/
0b0acbec	260	result = remove_memory(start, len);
1da177e4 LT	261	if (result) {
	262	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Hot-Remove failed.\n"));
	263	return_VALUE(result);
	264	}
	265
	266	/* Power-off and eject the device */
	267	result = acpi_memory_powerdown_device(mem_device);
	268	if (result) {
	269	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	270	"Device Power Down failed.\n"));
1da177e4 LT	271	/* Set the status of the device to invalid */
	272	mem_device->state = MEMORY_INVALID_STATE;
	273	return result;
	274	}
	275
	276	mem_device->state = MEMORY_POWER_OFF_STATE;
	277	return result;
	278	}
	279
4be44fcd	280	static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
1da177e4 LT	281	{
	282	struct acpi_memory_device *mem_device;
	283	struct acpi_device *device;
	284
	285	ACPI_FUNCTION_TRACE("acpi_memory_device_notify");
	286
	287	switch (event) {
	288	case ACPI_NOTIFY_BUS_CHECK:
	289	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	290	"\nReceived BUS CHECK notification for device\n"));
1da177e4 LT	291	/* Fall Through */
	292	case ACPI_NOTIFY_DEVICE_CHECK:
	293	if (event == ACPI_NOTIFY_DEVICE_CHECK)
	294	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	295	"\nReceived DEVICE CHECK notification for device\n"));
1da177e4 LT	296	if (acpi_memory_get_device(handle, &mem_device)) {
1da177e4 LT	297	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	298	"Error in finding driver data\n"));
1da177e4 LT	299	return_VOID;
	300	}
	301
	302	if (!acpi_memory_check_device(mem_device)) {
	303	if (acpi_memory_enable_device(mem_device))
	304	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	305	"Error in acpi_memory_enable_device\n"));
1da177e4 LT	306	}
	307	break;
	308	case ACPI_NOTIFY_EJECT_REQUEST:
	309	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	310	"\nReceived EJECT REQUEST notification for device\n"));
1da177e4 LT	311
	312	if (acpi_bus_get_device(handle, &device)) {
	313	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	314	"Device doesn't exist\n"));
1da177e4 LT	315	break;
	316	}
	317	mem_device = acpi_driver_data(device);
	318	if (!mem_device) {
	319	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	320	"Driver Data is NULL\n"));
1da177e4 LT	321	break;
	322	}
	323
	324	/*
	325	* Currently disabling memory device from kernel mode
	326	* TBD: Can also be disabled from user mode scripts
	327	* TBD: Can also be disabled by Callback registration
4be44fcd	328	* with generic sysfs driver
1da177e4 LT	329	*/
	330	if (acpi_memory_disable_device(mem_device))
	331	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	332	"Error in acpi_memory_disable_device\n"));
1da177e4 LT	333	/*
	334	* TBD: Invoke acpi_bus_remove to cleanup data structures
	335	*/
	336	break;
	337	default:
	338	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	339	"Unsupported event [0x%x]\n", event));
1da177e4 LT	340	break;
	341	}
	342
	343	return_VOID;
	344	}
	345
4be44fcd	346	static int acpi_memory_device_add(struct acpi_device *device)
1da177e4 LT	347	{
	348	int result;
	349	struct acpi_memory_device *mem_device = NULL;
	350
	351	ACPI_FUNCTION_TRACE("acpi_memory_device_add");
	352
	353	if (!device)
	354	return_VALUE(-EINVAL);
	355
	356	mem_device = kmalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
	357	if (!mem_device)
	358	return_VALUE(-ENOMEM);
	359	memset(mem_device, 0, sizeof(struct acpi_memory_device));
	360
	361	mem_device->handle = device->handle;
	362	sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
	363	sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
	364	acpi_driver_data(device) = mem_device;
	365
	366	/* Get the range from the _CRS */
	367	result = acpi_memory_get_device_resources(mem_device);
	368	if (result) {
	369	kfree(mem_device);
	370	return_VALUE(result);
	371	}
	372
	373	/* Set the device state */
	374	mem_device->state = MEMORY_POWER_ON_STATE;
	375
	376	printk(KERN_INFO "%s \n", acpi_device_name(device));
	377
	378	return_VALUE(result);
	379	}
	380
4be44fcd	381	static int acpi_memory_device_remove(struct acpi_device *device, int type)
1da177e4 LT	382	{
	383	struct acpi_memory_device *mem_device = NULL;
	384
	385	ACPI_FUNCTION_TRACE("acpi_memory_device_remove");
	386
	387	if (!device \|\| !acpi_driver_data(device))
	388	return_VALUE(-EINVAL);
	389
4be44fcd	390	mem_device = (struct acpi_memory_device *)acpi_driver_data(device);
1da177e4 LT	391	kfree(mem_device);
	392
	393	return_VALUE(0);
	394	}
	395
	396	/*
	397	* Helper function to check for memory device
	398	*/
4be44fcd	399	static acpi_status is_memory_device(acpi_handle handle)
1da177e4 LT	400	{
	401	char *hardware_id;
	402	acpi_status status;
4be44fcd	403	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1da177e4 LT	404	struct acpi_device_info *info;
	405
	406	ACPI_FUNCTION_TRACE("is_memory_device");
	407
	408	status = acpi_get_object_info(handle, &buffer);
	409	if (ACPI_FAILURE(status))
	410	return_ACPI_STATUS(AE_ERROR);
	411
	412	info = buffer.pointer;
	413	if (!(info->valid & ACPI_VALID_HID)) {
	414	acpi_os_free(buffer.pointer);
	415	return_ACPI_STATUS(AE_ERROR);
	416	}
	417
	418	hardware_id = info->hardware_id.value;
	419	if ((hardware_id == NULL) \|\|
4be44fcd	420	(strcmp(hardware_id, ACPI_MEMORY_DEVICE_HID)))
1da177e4 LT	421	status = AE_ERROR;
	422
	423	acpi_os_free(buffer.pointer);
	424	return_ACPI_STATUS(status);
	425	}
	426
	427	static acpi_status
4be44fcd LB	428	acpi_memory_register_notify_handler(acpi_handle handle,
4be44fcd LB	429	u32 level, void ctxt, void *retv)
1da177e4 LT	430	{
	431	acpi_status status;
	432
	433	ACPI_FUNCTION_TRACE("acpi_memory_register_notify_handler");
	434
	435	status = is_memory_device(handle);
	436	if (ACPI_FAILURE(status))
	437	return_ACPI_STATUS(AE_OK); /* continue */
	438
	439	status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
4be44fcd	440	acpi_memory_device_notify, NULL);
1da177e4 LT	441	if (ACPI_FAILURE(status)) {
1da177e4 LT	442	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	443	"Error installing notify handler\n"));
1da177e4 LT	444	return_ACPI_STATUS(AE_OK); /* continue */
	445	}
	446
	447	return_ACPI_STATUS(status);
	448	}
	449
	450	static acpi_status
4be44fcd LB	451	acpi_memory_deregister_notify_handler(acpi_handle handle,
4be44fcd LB	452	u32 level, void ctxt, void *retv)
1da177e4 LT	453	{
	454	acpi_status status;
	455
	456	ACPI_FUNCTION_TRACE("acpi_memory_deregister_notify_handler");
	457
	458	status = is_memory_device(handle);
	459	if (ACPI_FAILURE(status))
	460	return_ACPI_STATUS(AE_OK); /* continue */
	461
	462	status = acpi_remove_notify_handler(handle,
4be44fcd LB	463	ACPI_SYSTEM_NOTIFY,
4be44fcd LB	464	acpi_memory_device_notify);
1da177e4 LT	465	if (ACPI_FAILURE(status)) {
1da177e4 LT	466	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	467	"Error removing notify handler\n"));
1da177e4 LT	468	return_ACPI_STATUS(AE_OK); /* continue */
	469	}
	470
	471	return_ACPI_STATUS(status);
	472	}
	473
4be44fcd	474	static int __init acpi_memory_device_init(void)
1da177e4 LT	475	{
	476	int result;
	477	acpi_status status;
	478
	479	ACPI_FUNCTION_TRACE("acpi_memory_device_init");
	480
	481	result = acpi_bus_register_driver(&acpi_memory_device_driver);
	482
	483	if (result < 0)
	484	return_VALUE(-ENODEV);
	485
	486	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
4be44fcd LB	487	ACPI_UINT32_MAX,
	488	acpi_memory_register_notify_handler,
	489	NULL, NULL);
1da177e4	490
4be44fcd LB	491	if (ACPI_FAILURE(status)) {
4be44fcd LB	492	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "walk_namespace failed\n"));
1da177e4 LT	493	acpi_bus_unregister_driver(&acpi_memory_device_driver);
1da177e4 LT	494	return_VALUE(-ENODEV);
4be44fcd	495	}
1da177e4 LT	496
	497	return_VALUE(0);
	498	}
	499
4be44fcd	500	static void __exit acpi_memory_device_exit(void)
1da177e4 LT	501	{
	502	acpi_status status;
	503
	504	ACPI_FUNCTION_TRACE("acpi_memory_device_exit");
	505
	506	/*
	507	* Adding this to un-install notification handlers for all the device
	508	* handles.
	509	*/
	510	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
4be44fcd LB	511	ACPI_UINT32_MAX,
	512	acpi_memory_deregister_notify_handler,
	513	NULL, NULL);
1da177e4	514
4be44fcd LB	515	if (ACPI_FAILURE(status))
4be44fcd LB	516	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "walk_namespace failed\n"));
1da177e4 LT	517
	518	acpi_bus_unregister_driver(&acpi_memory_device_driver);
	519
	520	return_VOID;
	521	}
	522
	523	module_init(acpi_memory_device_init);
	524	module_exit(acpi_memory_device_exit);