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

/*
 * Copyright (C) 2004 Intel Corporation <naveen.b.s@intel.com>
 *
 * All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or (at
 * your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 * NON INFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *
 * ACPI based HotPlug driver that supports Memory Hotplug
 * This driver fields notifications from firmare for memory add
 * and remove operations and alerts the VM of the affected memory
 * ranges.
 */

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

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

#define _COMPONENT		ACPI_MEMORY_DEVICE_COMPONENT

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

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

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

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

static 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_EXCEPTION((AE_INFO, status, "Cannot find acpi parent"));
		return_VALUE(-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_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_EXCEPTION((AE_INFO, status, "Cannot add acpi bus"));
		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) {
		printk(KERN_ERR PREFIX "get_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) {
		printk(KERN_ERR PREFIX "add_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_EXCEPTION((AE_INFO, status, "_EJ0 failed"));
		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)
		return_VALUE(result);

	/* 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;

	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)) {
			printk(KERN_ERR PREFIX "Cannot find driver data\n");
			return_VOID;
		}

		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_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(status);

	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)){
		ACPI_EXCEPTION((AE_INFO, status, "handle is no memory device"));
		return_ACPI_STATUS(AE_OK);	/* continue */
	}

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

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)){
		ACPI_EXCEPTION((AE_INFO, status, "handle is no memory device"));
		return_ACPI_STATUS(AE_OK);	/* continue */
	}

	status = acpi_remove_notify_handler(handle,
					    ACPI_SYSTEM_NOTIFY,
					    acpi_memory_device_notify);

	return_ACPI_STATUS(AE_OK);	/* continue */
}

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_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
		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_EXCEPTION((AE_INFO, status, "walk_namespace failed"));

	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)) {
a6fc6720	128	ACPI_EXCEPTION((AE_INFO, status, "Cannot find acpi parent"));
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)) {
a6fc6720	135	ACPI_EXCEPTION((AE_INFO, status, "Cannot get acpi bus device"));
1da177e4 LT	136	return_VALUE(-EINVAL);
	137	}
	138
	139	/*
	140	* Now add the notified device. This creates the acpi_device
	141	* and invokes .add function
	142	*/
	143	status = acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE);
	144	if (ACPI_FAILURE(status)) {
a6fc6720	145	ACPI_EXCEPTION((AE_INFO, status, "Cannot add acpi bus"));
1da177e4 LT	146	return_VALUE(-EINVAL);
	147	}
	148
4be44fcd	149	end:
1da177e4 LT	150	*mem_device = acpi_driver_data(device);
1da177e4 LT	151	if (!(*mem_device)) {
4be44fcd	152	printk(KERN_ERR "\n driver data not found");
1da177e4 LT	153	return_VALUE(-ENODEV);
	154	}
	155
	156	return_VALUE(0);
	157	}
	158
4be44fcd	159	static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
1da177e4 LT	160	{
	161	unsigned long current_status;
	162
	163	ACPI_FUNCTION_TRACE("acpi_memory_check_device");
	164
	165	/* Get device present/absent information from the _STA */
	166	if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->handle, "_STA",
4be44fcd	167	NULL, &current_status)))
1da177e4 LT	168	return_VALUE(-ENODEV);
	169	/*
	170	* Check for device status. Device should be
	171	* present/enabled/functioning.
	172	*/
	173	if (!((current_status & ACPI_MEMORY_STA_PRESENT)
4be44fcd LB	174	&& (current_status & ACPI_MEMORY_STA_ENABLED)
4be44fcd LB	175	&& (current_status & ACPI_MEMORY_STA_FUNCTIONAL)))
1da177e4 LT	176	return_VALUE(-ENODEV);
	177
	178	return_VALUE(0);
	179	}
	180
4be44fcd	181	static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
1da177e4 LT	182	{
	183	int result;
	184
	185	ACPI_FUNCTION_TRACE("acpi_memory_enable_device");
	186
	187	/* Get the range from the _CRS */
	188	result = acpi_memory_get_device_resources(mem_device);
	189	if (result) {
6468463a	190	printk(KERN_ERR PREFIX "get_device_resources failed\n");
1da177e4 LT	191	mem_device->state = MEMORY_INVALID_STATE;
	192	return result;
	193	}
	194
	195	/*
	196	* Tell the VM there is more memory here...
	197	* Note: Assume that this function returns zero on success
	198	*/
459c7266	199	result = add_memory(mem_device->start_addr, mem_device->length);
1da177e4	200	if (result) {
6468463a	201	printk(KERN_ERR PREFIX "add_memory failed\n");
1da177e4 LT	202	mem_device->state = MEMORY_INVALID_STATE;
	203	return result;
	204	}
	205
	206	return result;
	207	}
	208
4be44fcd	209	static int acpi_memory_powerdown_device(struct acpi_memory_device *mem_device)
1da177e4 LT	210	{
1da177e4 LT	211	acpi_status status;
4be44fcd	212	struct acpi_object_list arg_list;
1da177e4 LT	213	union acpi_object arg;
	214	unsigned long current_status;
	215
	216	ACPI_FUNCTION_TRACE("acpi_memory_powerdown_device");
	217
	218	/* Issue the _EJ0 command */
	219	arg_list.count = 1;
	220	arg_list.pointer = &arg;
	221	arg.type = ACPI_TYPE_INTEGER;
	222	arg.integer.value = 1;
	223	status = acpi_evaluate_object(mem_device->handle,
4be44fcd	224	"_EJ0", &arg_list, NULL);
1da177e4 LT	225	/* Return on _EJ0 failure */
1da177e4 LT	226	if (ACPI_FAILURE(status)) {
a6fc6720	227	ACPI_EXCEPTION((AE_INFO, status, "_EJ0 failed"));
1da177e4 LT	228	return_VALUE(-ENODEV);
	229	}
	230
	231	/* Evalute _STA to check if the device is disabled */
	232	status = acpi_evaluate_integer(mem_device->handle, "_STA",
4be44fcd	233	NULL, &current_status);
1da177e4 LT	234	if (ACPI_FAILURE(status))
	235	return_VALUE(-ENODEV);
	236
	237	/* Check for device status. Device should be disabled */
	238	if (current_status & ACPI_MEMORY_STA_ENABLED)
	239	return_VALUE(-EINVAL);
	240
	241	return_VALUE(0);
	242	}
	243
4be44fcd	244	static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
1da177e4 LT	245	{
	246	int result;
	247	u64 start = mem_device->start_addr;
459c7266	248	u64 len = mem_device->length;
1da177e4 LT	249
	250	ACPI_FUNCTION_TRACE("acpi_memory_disable_device");
	251
	252	/*
	253	* Ask the VM to offline this memory range.
	254	* Note: Assume that this function returns zero on success
	255	*/
0b0acbec	256	result = remove_memory(start, len);
a6fc6720	257	if (result)
1da177e4	258	return_VALUE(result);
1da177e4 LT	259
	260	/* Power-off and eject the device */
	261	result = acpi_memory_powerdown_device(mem_device);
	262	if (result) {
1da177e4 LT	263	/* Set the status of the device to invalid */
	264	mem_device->state = MEMORY_INVALID_STATE;
	265	return result;
	266	}
	267
	268	mem_device->state = MEMORY_POWER_OFF_STATE;
	269	return result;
	270	}
	271
4be44fcd	272	static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
1da177e4 LT	273	{
	274	struct acpi_memory_device *mem_device;
	275	struct acpi_device *device;
	276
	277	ACPI_FUNCTION_TRACE("acpi_memory_device_notify");
	278
	279	switch (event) {
	280	case ACPI_NOTIFY_BUS_CHECK:
	281	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	282	"\nReceived BUS CHECK notification for device\n"));
1da177e4 LT	283	/* Fall Through */
	284	case ACPI_NOTIFY_DEVICE_CHECK:
	285	if (event == ACPI_NOTIFY_DEVICE_CHECK)
	286	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	287	"\nReceived DEVICE CHECK notification for device\n"));
1da177e4	288	if (acpi_memory_get_device(handle, &mem_device)) {
6468463a	289	printk(KERN_ERR PREFIX "Cannot find driver data\n");
1da177e4 LT	290	return_VOID;
	291	}
	292
	293	if (!acpi_memory_check_device(mem_device)) {
	294	if (acpi_memory_enable_device(mem_device))
6468463a LB	295	printk(KERN_ERR PREFIX
6468463a LB	296	"Cannot enable memory device\n");
1da177e4 LT	297	}
	298	break;
	299	case ACPI_NOTIFY_EJECT_REQUEST:
	300	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	301	"\nReceived EJECT REQUEST notification for device\n"));
1da177e4 LT	302
1da177e4 LT	303	if (acpi_bus_get_device(handle, &device)) {
6468463a	304	printk(KERN_ERR PREFIX "Device doesn't exist\n");
1da177e4 LT	305	break;
	306	}
	307	mem_device = acpi_driver_data(device);
	308	if (!mem_device) {
6468463a	309	printk(KERN_ERR PREFIX "Driver Data is NULL\n");
1da177e4 LT	310	break;
	311	}
	312
	313	/*
	314	* Currently disabling memory device from kernel mode
	315	* TBD: Can also be disabled from user mode scripts
	316	* TBD: Can also be disabled by Callback registration
4be44fcd	317	* with generic sysfs driver
1da177e4 LT	318	*/
1da177e4 LT	319	if (acpi_memory_disable_device(mem_device))
6468463a LB	320	printk(KERN_ERR PREFIX
6468463a LB	321	"Disable memory device\n");
1da177e4 LT	322	/*
	323	* TBD: Invoke acpi_bus_remove to cleanup data structures
	324	*/
	325	break;
	326	default:
	327	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
4be44fcd	328	"Unsupported event [0x%x]\n", event));
1da177e4 LT	329	break;
	330	}
	331
	332	return_VOID;
	333	}
	334
4be44fcd	335	static int acpi_memory_device_add(struct acpi_device *device)
1da177e4 LT	336	{
	337	int result;
	338	struct acpi_memory_device *mem_device = NULL;
	339
	340	ACPI_FUNCTION_TRACE("acpi_memory_device_add");
	341
	342	if (!device)
	343	return_VALUE(-EINVAL);
	344
	345	mem_device = kmalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
	346	if (!mem_device)
	347	return_VALUE(-ENOMEM);
	348	memset(mem_device, 0, sizeof(struct acpi_memory_device));
	349
	350	mem_device->handle = device->handle;
	351	sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
	352	sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
	353	acpi_driver_data(device) = mem_device;
	354
	355	/* Get the range from the _CRS */
	356	result = acpi_memory_get_device_resources(mem_device);
	357	if (result) {
	358	kfree(mem_device);
	359	return_VALUE(result);
	360	}
	361
	362	/* Set the device state */
	363	mem_device->state = MEMORY_POWER_ON_STATE;
	364
	365	printk(KERN_INFO "%s \n", acpi_device_name(device));
	366
	367	return_VALUE(result);
	368	}
	369
4be44fcd	370	static int acpi_memory_device_remove(struct acpi_device *device, int type)
1da177e4 LT	371	{
	372	struct acpi_memory_device *mem_device = NULL;
	373
	374	ACPI_FUNCTION_TRACE("acpi_memory_device_remove");
	375
	376	if (!device \|\| !acpi_driver_data(device))
	377	return_VALUE(-EINVAL);
	378
4be44fcd	379	mem_device = (struct acpi_memory_device *)acpi_driver_data(device);
1da177e4 LT	380	kfree(mem_device);
	381
	382	return_VALUE(0);
	383	}
	384
	385	/*
	386	* Helper function to check for memory device
	387	*/
4be44fcd	388	static acpi_status is_memory_device(acpi_handle handle)
1da177e4 LT	389	{
	390	char *hardware_id;
	391	acpi_status status;
4be44fcd	392	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1da177e4 LT	393	struct acpi_device_info *info;
	394
	395	ACPI_FUNCTION_TRACE("is_memory_device");
	396
	397	status = acpi_get_object_info(handle, &buffer);
	398	if (ACPI_FAILURE(status))
a6fc6720	399	return_ACPI_STATUS(status);
1da177e4 LT	400
	401	info = buffer.pointer;
	402	if (!(info->valid & ACPI_VALID_HID)) {
	403	acpi_os_free(buffer.pointer);
	404	return_ACPI_STATUS(AE_ERROR);
	405	}
	406
	407	hardware_id = info->hardware_id.value;
	408	if ((hardware_id == NULL) \|\|
4be44fcd	409	(strcmp(hardware_id, ACPI_MEMORY_DEVICE_HID)))
1da177e4 LT	410	status = AE_ERROR;
	411
	412	acpi_os_free(buffer.pointer);
	413	return_ACPI_STATUS(status);
	414	}
	415
	416	static acpi_status
4be44fcd LB	417	acpi_memory_register_notify_handler(acpi_handle handle,
4be44fcd LB	418	u32 level, void ctxt, void *retv)
1da177e4 LT	419	{
	420	acpi_status status;
	421
	422	ACPI_FUNCTION_TRACE("acpi_memory_register_notify_handler");
	423
	424	status = is_memory_device(handle);
a6fc6720 TR	425	if (ACPI_FAILURE(status)){
a6fc6720 TR	426	ACPI_EXCEPTION((AE_INFO, status, "handle is no memory device"));
1da177e4	427	return_ACPI_STATUS(AE_OK); /* continue */
a6fc6720	428	}
1da177e4 LT	429
1da177e4 LT	430	status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
4be44fcd	431	acpi_memory_device_notify, NULL);
a6fc6720 TR	432	/* continue */
a6fc6720 TR	433	return_ACPI_STATUS(AE_OK);
1da177e4 LT	434	}
	435
	436	static acpi_status
4be44fcd LB	437	acpi_memory_deregister_notify_handler(acpi_handle handle,
4be44fcd LB	438	u32 level, void ctxt, void *retv)
1da177e4 LT	439	{
	440	acpi_status status;
	441
	442	ACPI_FUNCTION_TRACE("acpi_memory_deregister_notify_handler");
	443
	444	status = is_memory_device(handle);
a6fc6720 TR	445	if (ACPI_FAILURE(status)){
a6fc6720 TR	446	ACPI_EXCEPTION((AE_INFO, status, "handle is no memory device"));
1da177e4	447	return_ACPI_STATUS(AE_OK); /* continue */
a6fc6720	448	}
1da177e4 LT	449
1da177e4 LT	450	status = acpi_remove_notify_handler(handle,
4be44fcd LB	451	ACPI_SYSTEM_NOTIFY,
4be44fcd LB	452	acpi_memory_device_notify);
1da177e4	453
a6fc6720	454	return_ACPI_STATUS(AE_OK); /* continue */
1da177e4 LT	455	}
1da177e4 LT	456
4be44fcd	457	static int __init acpi_memory_device_init(void)
1da177e4 LT	458	{
	459	int result;
	460	acpi_status status;
	461
	462	ACPI_FUNCTION_TRACE("acpi_memory_device_init");
	463
	464	result = acpi_bus_register_driver(&acpi_memory_device_driver);
	465
	466	if (result < 0)
	467	return_VALUE(-ENODEV);
	468
	469	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
4be44fcd LB	470	ACPI_UINT32_MAX,
	471	acpi_memory_register_notify_handler,
	472	NULL, NULL);
1da177e4	473
4be44fcd	474	if (ACPI_FAILURE(status)) {
a6fc6720	475	ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
1da177e4 LT	476	acpi_bus_unregister_driver(&acpi_memory_device_driver);
1da177e4 LT	477	return_VALUE(-ENODEV);
4be44fcd	478	}
1da177e4 LT	479
	480	return_VALUE(0);
	481	}
	482
4be44fcd	483	static void __exit acpi_memory_device_exit(void)
1da177e4 LT	484	{
	485	acpi_status status;
	486
	487	ACPI_FUNCTION_TRACE("acpi_memory_device_exit");
	488
	489	/*
	490	* Adding this to un-install notification handlers for all the device
	491	* handles.
	492	*/
	493	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
4be44fcd LB	494	ACPI_UINT32_MAX,
	495	acpi_memory_deregister_notify_handler,
	496	NULL, NULL);
1da177e4	497
4be44fcd	498	if (ACPI_FAILURE(status))
a6fc6720	499	ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
1da177e4 LT	500
	501	acpi_bus_unregister_driver(&acpi_memory_device_driver);
	502
	503	return_VOID;
	504	}
	505
	506	module_init(acpi_memory_device_init);
	507	module_exit(acpi_memory_device_exit);