evxface.c

内核linux2.4.20,可跟rtlinux3.2打补丁 组成实时linux系统,编译内核

/******************************************************************************
 *
 * Module Name: evxface - External interfaces for ACPI events
 *              $Revision: 116 $
 *
 *****************************************************************************/

/*
 *  Copyright (C) 2000, 2001 R. Byron Moore
 *
 *  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.  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */


#include "acpi.h"
#include "achware.h"
#include "acnamesp.h"
#include "acevents.h"
#include "amlcode.h"
#include "acinterp.h"

#define _COMPONENT          ACPI_EVENTS
	 MODULE_NAME         ("evxface")


/*******************************************************************************
 *
 * 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;


	FUNCTION_TRACE ("Acpi_install_fixed_event_handler");


	/* Parameter validation */

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

	acpi_ut_acquire_mutex (ACPI_MTX_EVENTS);

	/* Don't allow two handlers. */

	if (NULL != acpi_gbl_fixed_event_handlers[event].handler) {
		status = AE_EXIST;
		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_enable_event (event, ACPI_EVENT_FIXED, 0);
	if (!ACPI_SUCCESS (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:
	acpi_ut_release_mutex (ACPI_MTX_EVENTS);
	return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * 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;


	FUNCTION_TRACE ("Acpi_remove_fixed_event_handler");


	/* Parameter validation */

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

	acpi_ut_acquire_mutex (ACPI_MTX_EVENTS);

	/* Disable the event before removing the handler */

	status = acpi_disable_event(event, ACPI_EVENT_FIXED, 0);

	/* Always Remove the handler */

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

	if (!ACPI_SUCCESS (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));
	}

	acpi_ut_release_mutex (ACPI_MTX_EVENTS);
	return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * 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)
 *              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)
{
	acpi_operand_object     *obj_desc;
	acpi_operand_object     *notify_obj;
	acpi_namespace_node     *device_node;
	acpi_status             status = AE_OK;


	FUNCTION_TRACE ("Acpi_install_notify_handler");


	/* Parameter validation */

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

	acpi_ut_acquire_mutex (ACPI_MTX_NAMESPACE);

	/* Convert and validate the device handle */

	device_node = acpi_ns_map_handle_to_node (device);
	if (!device_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_sys_notify.handler) ||
			((handler_type == ACPI_DEVICE_NOTIFY) &&
			  acpi_gbl_drv_notify.handler)) {
			status = AE_EXIST;
			goto unlock_and_exit;
		}

		if (handler_type == ACPI_SYSTEM_NOTIFY) {
			acpi_gbl_sys_notify.node = device_node;
			acpi_gbl_sys_notify.handler = handler;
			acpi_gbl_sys_notify.context = context;
		}
		else /* ACPI_DEVICE_NOTIFY */ {
			acpi_gbl_drv_notify.node = device_node;
			acpi_gbl_drv_notify.handler = handler;
			acpi_gbl_drv_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 {
		/*
		 * These are the ONLY objects that can receive ACPI notifications
		 */
		if ((device_node->type != ACPI_TYPE_DEVICE)    &&
			(device_node->type != ACPI_TYPE_PROCESSOR) &&
			(device_node->type != ACPI_TYPE_POWER)     &&
			(device_node->type != ACPI_TYPE_THERMAL)) {
			status = AE_BAD_PARAMETER;
			goto unlock_and_exit;
		}

		/* Check for an existing internal object */

		obj_desc = acpi_ns_get_attached_object (device_node);
		if (obj_desc) {

			/* Object exists - make sure there's no handler */

			if (((handler_type == ACPI_SYSTEM_NOTIFY) &&
				  obj_desc->device.sys_handler) ||
				((handler_type == ACPI_DEVICE_NOTIFY) &&
				  obj_desc->device.drv_handler)) {
				status = AE_EXIST;
				goto unlock_and_exit;
			}
		}

		else {
			/* Create a new object */

			obj_desc = acpi_ut_create_internal_object (device_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, (u8) device_node->type);
			if (ACPI_FAILURE (status)) {
				goto unlock_and_exit;
			}
		}

		/* Install the handler */

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

		notify_obj->notify_handler.node = device_node;
		notify_obj->notify_handler.handler = handler;
		notify_obj->notify_handler.context = context;


		if (handler_type == ACPI_SYSTEM_NOTIFY) {
			obj_desc->device.sys_handler = notify_obj;
		}

		else /* ACPI_DEVICE_NOTIFY */ {
			obj_desc->device.drv_handler = notify_obj;
		}
	}


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