evxface.c

linux-2.6.15.6

/******************************************************************************
 *
 * Module Name: evxface - External interfaces for ACPI events
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2005, R. Byron Moore
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */

#include <linux/module.h>

#include <acpi/acpi.h>
#include <acpi/acnamesp.h>
#include <acpi/acevents.h>
#include <acpi/acinterp.h>

#define _COMPONENT          ACPI_EVENTS
ACPI_MODULE_NAME("evxface")

/*******************************************************************************
 *
 * FUNCTION:    acpi_install_exception_handler
 *
 * PARAMETERS:  Handler         - Pointer to the handler function for the
 *                                event
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Saves the pointer to the handler function
 *
 ******************************************************************************/
#ifdef ACPI_FUTURE_USAGE
acpi_status acpi_install_exception_handler(acpi_exception_handler handler)
{
	acpi_status status;

	ACPI_FUNCTION_TRACE("acpi_install_exception_handler");

	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Don't allow two handlers. */

	if (acpi_gbl_exception_handler) {
		status = AE_ALREADY_EXISTS;
		goto cleanup;
	}

	/* Install the handler */

	acpi_gbl_exception_handler = handler;

      cleanup:
	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
	return_ACPI_STATUS(status);
}
#endif				/*  ACPI_FUTURE_USAGE  */

/*******************************************************************************
 *
 * FUNCTION:    acpi_install_fixed_event_handler
 *
 * PARAMETERS:  Event           - Event type to enable.
 *              Handler         - Pointer to the handler function for the
 *                                event
 *              Context         - Value passed to the handler on each GPE
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Saves the pointer to the handler function and then enables the
 *              event.
 *
 ******************************************************************************/

acpi_status
acpi_install_fixed_event_handler(u32 event,
				 acpi_event_handler handler, void *context)
{
	acpi_status status;

	ACPI_FUNCTION_TRACE("acpi_install_fixed_event_handler");

	/* Parameter validation */

	if (event > ACPI_EVENT_MAX) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Don't allow two handlers. */

	if (NULL != acpi_gbl_fixed_event_handlers[event].handler) {
		status = AE_ALREADY_EXISTS;
		goto cleanup;
	}

	/* Install the handler before enabling the event */

	acpi_gbl_fixed_event_handlers[event].handler = handler;
	acpi_gbl_fixed_event_handlers[event].context = context;

	status = acpi_clear_event(event);
	if (ACPI_SUCCESS(status))
		status = acpi_enable_event(event, 0);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_WARN,
				  "Could not enable fixed event.\n"));

		/* Remove the handler */

		acpi_gbl_fixed_event_handlers[event].handler = NULL;
		acpi_gbl_fixed_event_handlers[event].context = NULL;
	} else {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Enabled fixed event %X, Handler=%p\n", event,
				  handler));
	}

      cleanup:
	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
	return_ACPI_STATUS(status);
}

EXPORT_SYMBOL(acpi_install_fixed_event_handler);

/*******************************************************************************
 *
 * FUNCTION:    acpi_remove_fixed_event_handler
 *
 * PARAMETERS:  Event           - Event type to disable.
 *              Handler         - Address of the handler
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Disables the event and unregisters the event handler.
 *
 ******************************************************************************/

acpi_status
acpi_remove_fixed_event_handler(u32 event, acpi_event_handler handler)
{
	acpi_status status = AE_OK;

	ACPI_FUNCTION_TRACE("acpi_remove_fixed_event_handler");

	/* Parameter validation */

	if (event > ACPI_EVENT_MAX) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Disable the event before removing the handler */

	status = acpi_disable_event(event, 0);

	/* Always Remove the handler */

	acpi_gbl_fixed_event_handlers[event].handler = NULL;
	acpi_gbl_fixed_event_handlers[event].context = NULL;

	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_WARN,
				  "Could not write to fixed event enable register.\n"));
	} else {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Disabled fixed event %X.\n",
				  event));
	}

	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
	return_ACPI_STATUS(status);
}

EXPORT_SYMBOL(acpi_remove_fixed_event_handler);

/*******************************************************************************
 *
 * FUNCTION:    acpi_install_notify_handler
 *
 * PARAMETERS:  Device          - The device for which notifies will be handled
 *              handler_type    - The type of handler:
 *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
 *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
 *                                  ACPI_ALL_NOTIFY:  both system and device
 *              Handler         - Address of the handler
 *              Context         - Value passed to the handler on each GPE
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Install a handler for notifies on an ACPI device
 *
 ******************************************************************************/

acpi_status
acpi_install_notify_handler(acpi_handle device,
			    u32 handler_type,
			    acpi_notify_handler handler, void *context)
{
	union acpi_operand_object *obj_desc;
	union acpi_operand_object *notify_obj;
	struct acpi_namespace_node *node;
	acpi_status status;

	ACPI_FUNCTION_TRACE("acpi_install_notify_handler");

	/* Parameter validation */

	if ((!device) ||
	    (!handler) || (handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Convert and validate the device handle */

	node = acpi_ns_map_handle_to_node(device);
	if (!node) {
		status = AE_BAD_PARAMETER;
		goto unlock_and_exit;
	}

	/*
	 * Root Object:
	 * Registering a notify handler on the root object indicates that the
	 * caller wishes to receive notifications for all objects.  Note that
	 * only one <external> global handler can be regsitered (per notify type).
	 */
	if (device == ACPI_ROOT_OBJECT) {
		/* Make sure the handler is not already installed */

		if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
		     acpi_gbl_system_notify.handler) ||
		    ((handler_type & ACPI_DEVICE_NOTIFY) &&
		     acpi_gbl_device_notify.handler)) {
			status = AE_ALREADY_EXISTS;
			goto unlock_and_exit;
		}

		if (handler_type & ACPI_SYSTEM_NOTIFY) {
			acpi_gbl_system_notify.node = node;
			acpi_gbl_system_notify.handler = handler;
			acpi_gbl_system_notify.context = context;
		}

		if (handler_type & ACPI_DEVICE_NOTIFY) {
			acpi_gbl_device_notify.node = node;
			acpi_gbl_device_notify.handler = handler;
			acpi_gbl_device_notify.context = context;
		}

		/* Global notify handler installed */
	}

	/*
	 * All Other Objects:
	 * Caller will only receive notifications specific to the target object.
	 * Note that only certain object types can receive notifications.
	 */
	else {
		/* Notifies allowed on this object? */

		if (!acpi_ev_is_notify_object(node)) {
			status = AE_TYPE;
			goto unlock_and_exit;
		}

		/* Check for an existing internal object */

		obj_desc = acpi_ns_get_attached_object(node);
		if (obj_desc) {
			/* Object exists - make sure there's no handler */

			if (((handler_type & ACPI_SYSTEM_NOTIFY) &&
			     obj_desc->common_notify.system_notify) ||
			    ((handler_type & ACPI_DEVICE_NOTIFY) &&
			     obj_desc->common_notify.device_notify)) {
				status = AE_ALREADY_EXISTS;
				goto unlock_and_exit;
			}
		} else {
			/* Create a new object */

			obj_desc = acpi_ut_create_internal_object(node->type);
			if (!obj_desc) {
				status = AE_NO_MEMORY;
				goto unlock_and_exit;
			}

			/* Attach new object to the Node */

			status =
			    acpi_ns_attach_object(device, obj_desc, node->type);

			/* Remove local reference to the object */

			acpi_ut_remove_reference(obj_desc);
			if (ACPI_FAILURE(status)) {
				goto unlock_and_exit;
			}
		}

		/* Install the handler */

		notify_obj =
		    acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_NOTIFY);
		if (!notify_obj) {
			status = AE_NO_MEMORY;
			goto unlock_and_exit;
		}

		notify_obj->notify.node = node;
		notify_obj->notify.handler = handler;
		notify_obj->notify.context = context;

		if (handler_type & ACPI_SYSTEM_NOTIFY) {
			obj_desc->common_notify.system_notify = notify_obj;
		}

		if (handler_type & ACPI_DEVICE_NOTIFY) {
			obj_desc->common_notify.device_notify = notify_obj;
		}

		if (handler_type == ACPI_ALL_NOTIFY) {
			/* Extra ref if installed in both */

			acpi_ut_add_reference(notify_obj);
		}
	}

      unlock_and_exit:
	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
	return_ACPI_STATUS(status);
}

EXPORT_SYMBOL(acpi_install_notify_handler);

/*******************************************************************************
 *
 * FUNCTION:    acpi_remove_notify_handler
 *
 * PARAMETERS:  Device          - The device for which notifies will be handled
 *              handler_type    - The type of handler:
 *                                  ACPI_SYSTEM_NOTIFY: system_handler (00-7f)
 *                                  ACPI_DEVICE_NOTIFY: driver_handler (80-ff)
 *                                  ACPI_ALL_NOTIFY:  both system and device
 *              Handler         - Address of the handler
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Remove a handler for notifies on an ACPI device
 *
 ******************************************************************************/