Commit eb3d80f7 authored by Lv Zheng's avatar Lv Zheng Committed by Rafael J. Wysocki
Browse files

ACPICA: Events: Introduce acpi_set_gpe()/acpi_finish_gpe() to reduce divergences 



This can help to reduce source code differences between Linux and ACPICA
upstream. Further driver cleanups also require these APIs to eliminate GPE
storms.
1. acpi_set_gpe(): An API that driver should invoke in the case it wants
                   to disable/enable IRQ without honoring the reference
                   count implemented in the acpi_disable_gpe() and
                   acpi_enable_gpe(). Note that this API should only be
                   invoked inside a acpi_enable_gpe()/acpi_disable_gpe()
                   pair.
2. acpi_finish_gpe(): Drivers returned ACPI_REENABLE_GPE unset from the
                      GPE handler should use this API instead of
                      invoking acpi_set_gpe()/acpi_enable_gpe() to
                      re-enable the GPE.
The GPE APIs can be invoked inside of a GPE handler or in the task context
with a driver provided lock held. This driver provided lock is safe to be
held in the GPE handler by the driver.

Signed-off-by: default avatarLv Zheng <lv.zheng@intel.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 0d0988af

drivers/acpi/acpica/evxfgpe.c

+105 −0
Original line number Diff line number Diff line
@@ -183,6 +183,68 @@ acpi_status acpi_disable_gpe(acpi_handle gpe_device, u32 gpe_number) 


ACPI_EXPORT_SYMBOL(acpi_disable_gpe)



/*******************************************************************************

 *

 * FUNCTION:    acpi_set_gpe

 *

 * PARAMETERS:  gpe_device          - Parent GPE Device. NULL for GPE0/GPE1

 *              gpe_number          - GPE level within the GPE block

 *              action              - ACPI_GPE_ENABLE or ACPI_GPE_DISABLE

 *

 * RETURN:      Status

 *

 * DESCRIPTION: Enable or disable an individual GPE. This function bypasses

 *              the reference count mechanism used in the acpi_enable_gpe and

 *              acpi_disable_gpe interfaces -- and should be used with care.

 *

 * Note: Typically used to disable a runtime GPE for short period of time,

 * then re-enable it, without disturbing the existing reference counts. This

 * is useful, for example, in the Embedded Controller (EC) driver.

 *

 ******************************************************************************/

acpi_status acpi_set_gpe(acpi_handle gpe_device, u32 gpe_number, u8 action)

{

	struct acpi_gpe_event_info *gpe_event_info;

	acpi_status status;

	acpi_cpu_flags flags;



	ACPI_FUNCTION_TRACE(acpi_set_gpe);



	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);



	/* Ensure that we have a valid GPE number */



	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);

	if (!gpe_event_info) {

		status = AE_BAD_PARAMETER;

		goto unlock_and_exit;

	}



	/* Perform the action */



	switch (action) {

	case ACPI_GPE_ENABLE:



		status = acpi_ev_enable_gpe(gpe_event_info);

		break;



	case ACPI_GPE_DISABLE:



		status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);

		break;



	default:



		status = AE_BAD_PARAMETER;

		break;

	}



unlock_and_exit:

	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);

	return_ACPI_STATUS(status);

}



ACPI_EXPORT_SYMBOL(acpi_set_gpe)



/*******************************************************************************

 *
@@ -530,6 +592,49 @@ unlock_and_exit: 


ACPI_EXPORT_SYMBOL(acpi_get_gpe_status)



/*******************************************************************************

 *

 * FUNCTION:    acpi_finish_gpe

 *

 * PARAMETERS:  gpe_device          - Namespace node for the GPE Block

 *                                    (NULL for FADT defined GPEs)

 *              gpe_number          - GPE level within the GPE block

 *

 * RETURN:      Status

 *

 * DESCRIPTION: Clear and conditionally reenable a GPE. This completes the GPE

 *              processing. Intended for use by asynchronous host-installed

 *              GPE handlers. The GPE is only reenabled if the enable_for_run bit

 *              is set in the GPE info.

 *

 ******************************************************************************/

acpi_status acpi_finish_gpe(acpi_handle gpe_device, u32 gpe_number)

{

	struct acpi_gpe_event_info *gpe_event_info;

	acpi_status status;

	acpi_cpu_flags flags;



	ACPI_FUNCTION_TRACE(acpi_finish_gpe);



	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);



	/* Ensure that we have a valid GPE number */



	gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number);

	if (!gpe_event_info) {

		status = AE_BAD_PARAMETER;

		goto unlock_and_exit;

	}



	status = acpi_ev_finish_gpe(gpe_event_info);



unlock_and_exit:

	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);

	return_ACPI_STATUS(status);

}



ACPI_EXPORT_SYMBOL(acpi_finish_gpe)



/******************************************************************************

 *

 * FUNCTION:    acpi_disable_all_gpes

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