[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 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 length;		/* Memory Range length */
};

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->length = address64.address_length;
		}
	}

	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->length);
	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->length;

	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	76	u64 start_addr; /* Memory Range start physical addr */
459c7266	77	u64 length; /* Memory Range length */
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 */
459c7266	100	mem_device->caching = address64.info.mem.caching;
3963f008 KH	101	mem_device->write_protect =
3963f008 KH	102	address64.info.mem.write_protect;
50eca3eb	103	mem_device->start_addr = address64.minimum;
459c7266	104	mem_device->length = address64.address_length;
1da177e4 LT	105	}
	106	}
	107
	108	acpi_os_free(buffer.pointer);
	109	return_VALUE(0);
	110	}
	111
	112	static int
	113	acpi_memory_get_device(acpi_handle handle,
4be44fcd	114	struct acpi_memory_device **mem_device)
1da177e4 LT	115	{
	116	acpi_status status;
	117	acpi_handle phandle;
	118	struct acpi_device *device = NULL;
	119	struct acpi_device *pdevice = NULL;
	120
	121	ACPI_FUNCTION_TRACE("acpi_memory_get_device");
	122
	123	if (!acpi_bus_get_device(handle, &device) && device)
	124	goto end;
	125
	126	status = acpi_get_parent(handle, &phandle);
	127	if (ACPI_FAILURE(status)) {
4be44fcd	128	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error in acpi_get_parent\n"));
1da177e4 LT	129	return_VALUE(-EINVAL);
	130	}
	131
	132	/* Get the parent device */
	133	status = acpi_bus_get_device(phandle, &pdevice);
	134	if (ACPI_FAILURE(status)) {
	135	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	136	"Error in acpi_bus_get_device\n"));
1da177e4 LT	137	return_VALUE(-EINVAL);
	138	}
	139
	140	/*
	141	* Now add the notified device. This creates the acpi_device
	142	* and invokes .add function
	143	*/
	144	status = acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE);
	145	if (ACPI_FAILURE(status)) {
4be44fcd	146	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error in acpi_bus_add\n"));
1da177e4 LT	147	return_VALUE(-EINVAL);
	148	}
	149
4be44fcd	150	end:
1da177e4 LT	151	*mem_device = acpi_driver_data(device);
1da177e4 LT	152	if (!(*mem_device)) {
4be44fcd	153	printk(KERN_ERR "\n driver data not found");
1da177e4 LT	154	return_VALUE(-ENODEV);
	155	}
	156
	157	return_VALUE(0);
	158	}
	159
4be44fcd	160	static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
1da177e4 LT	161	{
	162	unsigned long current_status;
	163
	164	ACPI_FUNCTION_TRACE("acpi_memory_check_device");
	165
	166	/* Get device present/absent information from the _STA */
	167	if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->handle, "_STA",
4be44fcd	168	NULL, &current_status)))
1da177e4 LT	169	return_VALUE(-ENODEV);
	170	/*
	171	* Check for device status. Device should be
	172	* present/enabled/functioning.
	173	*/
	174	if (!((current_status & ACPI_MEMORY_STA_PRESENT)
4be44fcd LB	175	&& (current_status & ACPI_MEMORY_STA_ENABLED)
4be44fcd LB	176	&& (current_status & ACPI_MEMORY_STA_FUNCTIONAL)))
1da177e4 LT	177	return_VALUE(-ENODEV);
	178
	179	return_VALUE(0);
	180	}
	181
4be44fcd	182	static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
1da177e4 LT	183	{
	184	int result;
	185
	186	ACPI_FUNCTION_TRACE("acpi_memory_enable_device");
	187
	188	/* Get the range from the _CRS */
	189	result = acpi_memory_get_device_resources(mem_device);
	190	if (result) {
	191	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	192	"\nget_device_resources failed\n"));
1da177e4 LT	193	mem_device->state = MEMORY_INVALID_STATE;
	194	return result;
	195	}
	196
	197	/*
	198	* Tell the VM there is more memory here...
	199	* Note: Assume that this function returns zero on success
	200	*/
459c7266	201	result = add_memory(mem_device->start_addr, mem_device->length);
1da177e4	202	if (result) {
4be44fcd	203	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "\nadd_memory failed\n"));
1da177e4 LT	204	mem_device->state = MEMORY_INVALID_STATE;
	205	return result;
	206	}
	207
	208	return result;
	209	}
	210
4be44fcd	211	static int acpi_memory_powerdown_device(struct acpi_memory_device *mem_device)
1da177e4 LT	212	{
1da177e4 LT	213	acpi_status status;
4be44fcd	214	struct acpi_object_list arg_list;
1da177e4 LT	215	union acpi_object arg;
	216	unsigned long current_status;
	217
	218	ACPI_FUNCTION_TRACE("acpi_memory_powerdown_device");
	219
	220	/* Issue the _EJ0 command */
	221	arg_list.count = 1;
	222	arg_list.pointer = &arg;
	223	arg.type = ACPI_TYPE_INTEGER;
	224	arg.integer.value = 1;
	225	status = acpi_evaluate_object(mem_device->handle,
4be44fcd	226	"_EJ0", &arg_list, NULL);
1da177e4 LT	227	/* Return on _EJ0 failure */
1da177e4 LT	228	if (ACPI_FAILURE(status)) {
4be44fcd	229	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "_EJ0 failed.\n"));
1da177e4 LT	230	return_VALUE(-ENODEV);
	231	}
	232
	233	/* Evalute _STA to check if the device is disabled */
	234	status = acpi_evaluate_integer(mem_device->handle, "_STA",
4be44fcd	235	NULL, &current_status);
1da177e4 LT	236	if (ACPI_FAILURE(status))
	237	return_VALUE(-ENODEV);
	238
	239	/* Check for device status. Device should be disabled */
	240	if (current_status & ACPI_MEMORY_STA_ENABLED)
	241	return_VALUE(-EINVAL);
	242
	243	return_VALUE(0);
	244	}
	245
4be44fcd	246	static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
1da177e4 LT	247	{
	248	int result;
	249	u64 start = mem_device->start_addr;
459c7266	250	u64 len = mem_device->length;
1da177e4 LT	251
	252	ACPI_FUNCTION_TRACE("acpi_memory_disable_device");
	253
	254	/*
	255	* Ask the VM to offline this memory range.
	256	* Note: Assume that this function returns zero on success
	257	*/
0b0acbec	258	result = remove_memory(start, len);
1da177e4 LT	259	if (result) {
	260	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Hot-Remove failed.\n"));
	261	return_VALUE(result);
	262	}
	263
	264	/* Power-off and eject the device */
	265	result = acpi_memory_powerdown_device(mem_device);
	266	if (result) {
	267	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	268	"Device Power Down failed.\n"));
1da177e4 LT	269	/* Set the status of the device to invalid */
	270	mem_device->state = MEMORY_INVALID_STATE;
	271	return result;
	272	}
	273
	274	mem_device->state = MEMORY_POWER_OFF_STATE;
	275	return result;
	276	}
	277
4be44fcd	278	static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
1da177e4 LT	279	{
	280	struct acpi_memory_device *mem_device;
	281	struct acpi_device *device;
	282
	283	ACPI_FUNCTION_TRACE("acpi_memory_device_notify");
	284
	285	switch (event) {
	286	case ACPI_NOTIFY_BUS_CHECK:
	287	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	288	"\nReceived BUS CHECK notification for device\n"));
1da177e4 LT	289	/* Fall Through */
	290	case ACPI_NOTIFY_DEVICE_CHECK:
	291	if (event == ACPI_NOTIFY_DEVICE_CHECK)
	292	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	293	"\nReceived DEVICE CHECK notification for device\n"));
1da177e4 LT	294	if (acpi_memory_get_device(handle, &mem_device)) {
1da177e4 LT	295	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	296	"Error in finding driver data\n"));
1da177e4 LT	297	return_VOID;
	298	}
	299
	300	if (!acpi_memory_check_device(mem_device)) {
	301	if (acpi_memory_enable_device(mem_device))
	302	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	303	"Error in acpi_memory_enable_device\n"));
1da177e4 LT	304	}
	305	break;
	306	case ACPI_NOTIFY_EJECT_REQUEST:
	307	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	308	"\nReceived EJECT REQUEST notification for device\n"));
1da177e4 LT	309
	310	if (acpi_bus_get_device(handle, &device)) {
	311	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	312	"Device doesn't exist\n"));
1da177e4 LT	313	break;
	314	}
	315	mem_device = acpi_driver_data(device);
	316	if (!mem_device) {
	317	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	318	"Driver Data is NULL\n"));
1da177e4 LT	319	break;
	320	}
	321
	322	/*
	323	* Currently disabling memory device from kernel mode
	324	* TBD: Can also be disabled from user mode scripts
	325	* TBD: Can also be disabled by Callback registration
4be44fcd	326	* with generic sysfs driver
1da177e4 LT	327	*/
	328	if (acpi_memory_disable_device(mem_device))
	329	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	330	"Error in acpi_memory_disable_device\n"));
1da177e4 LT	331	/*
	332	* TBD: Invoke acpi_bus_remove to cleanup data structures
	333	*/
	334	break;
	335	default:
	336	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	337	"Unsupported event [0x%x]\n", event));
1da177e4 LT	338	break;
	339	}
	340
	341	return_VOID;
	342	}
	343
4be44fcd	344	static int acpi_memory_device_add(struct acpi_device *device)
1da177e4 LT	345	{
	346	int result;
	347	struct acpi_memory_device *mem_device = NULL;
	348
	349	ACPI_FUNCTION_TRACE("acpi_memory_device_add");
	350
	351	if (!device)
	352	return_VALUE(-EINVAL);
	353
	354	mem_device = kmalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
	355	if (!mem_device)
	356	return_VALUE(-ENOMEM);
	357	memset(mem_device, 0, sizeof(struct acpi_memory_device));
	358
	359	mem_device->handle = device->handle;
	360	sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
	361	sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
	362	acpi_driver_data(device) = mem_device;
	363
	364	/* Get the range from the _CRS */
	365	result = acpi_memory_get_device_resources(mem_device);
	366	if (result) {
	367	kfree(mem_device);
	368	return_VALUE(result);
	369	}
	370
	371	/* Set the device state */
	372	mem_device->state = MEMORY_POWER_ON_STATE;
	373
	374	printk(KERN_INFO "%s \n", acpi_device_name(device));
	375
	376	return_VALUE(result);
	377	}
	378
4be44fcd	379	static int acpi_memory_device_remove(struct acpi_device *device, int type)
1da177e4 LT	380	{
	381	struct acpi_memory_device *mem_device = NULL;
	382
	383	ACPI_FUNCTION_TRACE("acpi_memory_device_remove");
	384
	385	if (!device \|\| !acpi_driver_data(device))
	386	return_VALUE(-EINVAL);
	387
4be44fcd	388	mem_device = (struct acpi_memory_device *)acpi_driver_data(device);
1da177e4 LT	389	kfree(mem_device);
	390
	391	return_VALUE(0);
	392	}
	393
	394	/*
	395	* Helper function to check for memory device
	396	*/
4be44fcd	397	static acpi_status is_memory_device(acpi_handle handle)
1da177e4 LT	398	{
	399	char *hardware_id;
	400	acpi_status status;
4be44fcd	401	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1da177e4 LT	402	struct acpi_device_info *info;
	403
	404	ACPI_FUNCTION_TRACE("is_memory_device");
	405
	406	status = acpi_get_object_info(handle, &buffer);
	407	if (ACPI_FAILURE(status))
	408	return_ACPI_STATUS(AE_ERROR);
	409
	410	info = buffer.pointer;
	411	if (!(info->valid & ACPI_VALID_HID)) {
	412	acpi_os_free(buffer.pointer);
	413	return_ACPI_STATUS(AE_ERROR);
	414	}
	415
	416	hardware_id = info->hardware_id.value;
	417	if ((hardware_id == NULL) \|\|
4be44fcd	418	(strcmp(hardware_id, ACPI_MEMORY_DEVICE_HID)))
1da177e4 LT	419	status = AE_ERROR;
	420
	421	acpi_os_free(buffer.pointer);
	422	return_ACPI_STATUS(status);
	423	}
	424
	425	static acpi_status
4be44fcd LB	426	acpi_memory_register_notify_handler(acpi_handle handle,
4be44fcd LB	427	u32 level, void ctxt, void *retv)
1da177e4 LT	428	{
	429	acpi_status status;
	430
	431	ACPI_FUNCTION_TRACE("acpi_memory_register_notify_handler");
	432
	433	status = is_memory_device(handle);
	434	if (ACPI_FAILURE(status))
	435	return_ACPI_STATUS(AE_OK); /* continue */
	436
	437	status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
4be44fcd	438	acpi_memory_device_notify, NULL);
1da177e4 LT	439	if (ACPI_FAILURE(status)) {
1da177e4 LT	440	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	441	"Error installing notify handler\n"));
1da177e4 LT	442	return_ACPI_STATUS(AE_OK); /* continue */
	443	}
	444
	445	return_ACPI_STATUS(status);
	446	}
	447
	448	static acpi_status
4be44fcd LB	449	acpi_memory_deregister_notify_handler(acpi_handle handle,
4be44fcd LB	450	u32 level, void ctxt, void *retv)
1da177e4 LT	451	{
	452	acpi_status status;
	453
	454	ACPI_FUNCTION_TRACE("acpi_memory_deregister_notify_handler");
	455
	456	status = is_memory_device(handle);
	457	if (ACPI_FAILURE(status))
	458	return_ACPI_STATUS(AE_OK); /* continue */
	459
	460	status = acpi_remove_notify_handler(handle,
4be44fcd LB	461	ACPI_SYSTEM_NOTIFY,
4be44fcd LB	462	acpi_memory_device_notify);
1da177e4 LT	463	if (ACPI_FAILURE(status)) {
1da177e4 LT	464	ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
4be44fcd	465	"Error removing notify handler\n"));
1da177e4 LT	466	return_ACPI_STATUS(AE_OK); /* continue */
	467	}
	468
	469	return_ACPI_STATUS(status);
	470	}
	471
4be44fcd	472	static int __init acpi_memory_device_init(void)
1da177e4 LT	473	{
	474	int result;
	475	acpi_status status;
	476
	477	ACPI_FUNCTION_TRACE("acpi_memory_device_init");
	478
	479	result = acpi_bus_register_driver(&acpi_memory_device_driver);
	480
	481	if (result < 0)
	482	return_VALUE(-ENODEV);
	483
	484	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
4be44fcd LB	485	ACPI_UINT32_MAX,
	486	acpi_memory_register_notify_handler,
	487	NULL, NULL);
1da177e4	488
4be44fcd LB	489	if (ACPI_FAILURE(status)) {
4be44fcd LB	490	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "walk_namespace failed\n"));
1da177e4 LT	491	acpi_bus_unregister_driver(&acpi_memory_device_driver);
1da177e4 LT	492	return_VALUE(-ENODEV);
4be44fcd	493	}
1da177e4 LT	494
	495	return_VALUE(0);
	496	}
	497
4be44fcd	498	static void __exit acpi_memory_device_exit(void)
1da177e4 LT	499	{
	500	acpi_status status;
	501
	502	ACPI_FUNCTION_TRACE("acpi_memory_device_exit");
	503
	504	/*
	505	* Adding this to un-install notification handlers for all the device
	506	* handles.
	507	*/
	508	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
4be44fcd LB	509	ACPI_UINT32_MAX,
	510	acpi_memory_deregister_notify_handler,
	511	NULL, NULL);
1da177e4	512
4be44fcd LB	513	if (ACPI_FAILURE(status))
4be44fcd LB	514	ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "walk_namespace failed\n"));
1da177e4 LT	515
	516	acpi_bus_unregister_driver(&acpi_memory_device_driver);
	517
	518	return_VOID;
	519	}
	520
	521	module_init(acpi_memory_device_init);
	522	module_exit(acpi_memory_device_exit);