alistair23-linux/drivers/acpi/events/evsci.c

/*******************************************************************************
 *
 * Module Name: evsci - System Control Interrupt configuration and
 *                      legacy to ACPI mode state transition functions
 *
 ******************************************************************************/

/*
 * Copyright (C) 2000 - 2006, 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 <acpi/acpi.h>
#include <acpi/acevents.h>

#define _COMPONENT          ACPI_EVENTS
ACPI_MODULE_NAME("evsci")

/* Local prototypes */
static u32 ACPI_SYSTEM_XFACE acpi_ev_sci_xrupt_handler(void *context);

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_sci_xrupt_handler
 *
 * PARAMETERS:  Context   - Calling Context
 *
 * RETURN:      Status code indicates whether interrupt was handled.
 *
 * DESCRIPTION: Interrupt handler that will figure out what function or
 *              control method to call to deal with a SCI.
 *
 ******************************************************************************/

static u32 ACPI_SYSTEM_XFACE acpi_ev_sci_xrupt_handler(void *context)
{
	struct acpi_gpe_xrupt_info *gpe_xrupt_list = context;
	u32 interrupt_handled = ACPI_INTERRUPT_NOT_HANDLED;

	ACPI_FUNCTION_TRACE(ev_sci_xrupt_handler);

	/*
	 * We are guaranteed by the ACPI CA initialization/shutdown code that
	 * if this interrupt handler is installed, ACPI is enabled.
	 */

	/*
	 * Fixed Events:
	 * Check for and dispatch any Fixed Events that have occurred
	 */
	interrupt_handled |= acpi_ev_fixed_event_detect();

	/*
	 * General Purpose Events:
	 * Check for and dispatch any GPEs that have occurred
	 */
	interrupt_handled |= acpi_ev_gpe_detect(gpe_xrupt_list);

	return_UINT32(interrupt_handled);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_gpe_xrupt_handler
 *
 * PARAMETERS:  Context   - Calling Context
 *
 * RETURN:      Status code indicates whether interrupt was handled.
 *
 * DESCRIPTION: Handler for GPE Block Device interrupts
 *
 ******************************************************************************/

u32 ACPI_SYSTEM_XFACE acpi_ev_gpe_xrupt_handler(void *context)
{
	struct acpi_gpe_xrupt_info *gpe_xrupt_list = context;
	u32 interrupt_handled = ACPI_INTERRUPT_NOT_HANDLED;

	ACPI_FUNCTION_TRACE(ev_gpe_xrupt_handler);

	/*
	 * We are guaranteed by the ACPI CA initialization/shutdown code that
	 * if this interrupt handler is installed, ACPI is enabled.
	 */

	/*
	 * GPEs:
	 * Check for and dispatch any GPEs that have occurred
	 */
	interrupt_handled |= acpi_ev_gpe_detect(gpe_xrupt_list);

	return_UINT32(interrupt_handled);
}

/******************************************************************************
 *
 * FUNCTION:    acpi_ev_install_sci_handler
 *
 * PARAMETERS:  none
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Installs SCI handler.
 *
 ******************************************************************************/

u32 acpi_ev_install_sci_handler(void)
{
	u32 status = AE_OK;

	ACPI_FUNCTION_TRACE(ev_install_sci_handler);

	status = acpi_os_install_interrupt_handler((u32) acpi_gbl_FADT->sci_int,
						   acpi_ev_sci_xrupt_handler,
						   acpi_gbl_gpe_xrupt_list_head);
	return_ACPI_STATUS(status);
}

/******************************************************************************
 *
 * FUNCTION:    acpi_ev_remove_sci_handler
 *
 * PARAMETERS:  none
 *
 * RETURN:      E_OK if handler uninstalled OK, E_ERROR if handler was not
 *              installed to begin with
 *
 * DESCRIPTION: Remove the SCI interrupt handler.  No further SCIs will be
 *              taken.
 *
 * Note:  It doesn't seem important to disable all events or set the event
 *        enable registers to their original values.  The OS should disable
 *        the SCI interrupt level when the handler is removed, so no more
 *        events will come in.
 *
 ******************************************************************************/

acpi_status acpi_ev_remove_sci_handler(void)
{
	acpi_status status;

	ACPI_FUNCTION_TRACE(ev_remove_sci_handler);

	/* Just let the OS remove the handler and disable the level */

	status = acpi_os_remove_interrupt_handler((u32) acpi_gbl_FADT->sci_int,
						  acpi_ev_sci_xrupt_handler);

	return_ACPI_STATUS(status);
}