linux_dsm_epyc7002/drivers/acpi/acpica/evxface.c
Lv Zheng 69c841b6dd ACPICA: Update use of acpi_os_wait_events_complete interface.
This patch cleans up all of the acpi_os_wait_events_complete() invocations to
make it to be invoked inside of ACPICA in the way to accommodate Linux's
work queue implementation.

According to the report, current Linux kernel code is facing a boot time
race issue in the acpi_remove_notify_handler(). This is because:
Linux is using work queues to implement a deferred handler call environment
while ACPICA expects OSPM to implement acpi_os_wait_events_complete() using
wait queues.  The position to invoke a "waiter" is not suitable for a
"flusher" as new invocations can be scheduled after this position and
before the deletion of the handler from its management container.

Since the following commit has deleted acpi_os_wait_events_complete()
parameters, it thus might not be possible for OSPM to achieve a safe
removal using wait queues.  This requires ACPICA to be changed accordingly
to "flush" handlers rather than "wait" them to be drain up:

  Commit: 5ff986a2a9db11858247b71fe242fe17617229aa
  Date: Wed, 16 May 2012 13:36:07 -0700
  Subject: Introduce acpi_os_wait_events_complete interface.

  This interface will block until asynchronous events like notifies
  and GPEs are complete. Within ACPICA, it is called before a notify or GPE
  handler is removed. ACPICA BZ 868.

This patch fixes this issue by invoking acpi_os_wait_events_complete() in the
way to "flush" things - it thus should be put to the position after handler
is removed from its management container but before it is destructed.

The technical concerns are:
1. MTX_NAMESPACE is used to protect things that acpi_os_wait_events_complete()
   might be waiting for, thus MTX_NAMESPACE must be unlocked before
   invoking acpi_os_wait_events_complete().
2. MTX_NAMESPACE is also used to implement the serialization of
   acpi_install_notify_handler() and acpi_remove_notify_handler(). This patch
   changes this logic, thus if there are many
   acpi_install/remove_notify_handler() invoked in parallel, the
   acpi_os_wait_events_complete() might face the races which could cause it
   never running to an end.  Normally this will require additional code to
   implement a separate locking facility which is not implemented due to 3.
3. Given ACPICA users will always invoke acpi_install_notify_handler() once
   during Linux module/device initialization and invoke
   acpi_remove_notify_handler() once during module/device finalization,
   problem stated in 2 will not happen in Linux environment due to the
   mutual exclusive module/device existence, this fix thus is sufficient.
Same concerns can apply to acpi_install/remove_gpe_handler(). Reported and
tested: Ronald Vink.  Fixed: Lv Zheng.

References: https://bugzilla.kernel.org/show_bug.cgi?id=60583
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reported-and-Tested-by: Ronald Vink <ronald.vink@boskalis.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-20 22:59:37 +02:00

1003 lines
28 KiB
C

/******************************************************************************
*
* Module Name: evxface - External interfaces for ACPI events
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2014, Intel Corp.
* 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.
*/
#define EXPORT_ACPI_INTERFACES
#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"
#include "acevents.h"
#include "acinterp.h"
#define _COMPONENT ACPI_EVENTS
ACPI_MODULE_NAME("evxface")
/*******************************************************************************
*
* 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: Device 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 notifications on an ACPI Device,
* thermal_zone, or Processor object.
*
* NOTES: The Root namespace object may have only one handler for each
* type of notify (System/Device). Device/Thermal/Processor objects
* may have one device notify handler, and multiple system notify
* handlers.
*
******************************************************************************/
acpi_status
acpi_install_notify_handler(acpi_handle device,
u32 handler_type,
acpi_notify_handler handler, void *context)
{
struct acpi_namespace_node *node =
ACPI_CAST_PTR(struct acpi_namespace_node, device);
union acpi_operand_object *obj_desc;
union acpi_operand_object *handler_obj;
acpi_status status;
u32 i;
ACPI_FUNCTION_TRACE(acpi_install_notify_handler);
/* Parameter validation */
if ((!device) || (!handler) || (!handler_type) ||
(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);
}
/*
* 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 global handler can be registered per notify type.
* Ensure that a handler is not already installed.
*/
if (device == ACPI_ROOT_OBJECT) {
for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
if (handler_type & (i + 1)) {
if (acpi_gbl_global_notify[i].handler) {
status = AE_ALREADY_EXISTS;
goto unlock_and_exit;
}
acpi_gbl_global_notify[i].handler = handler;
acpi_gbl_global_notify[i].context = context;
}
}
goto unlock_and_exit; /* Global notify handler installed, all done */
}
/*
* All Other Objects:
* Caller will only receive notifications specific to the target
* object. Note that only certain object types are allowed to
* receive notifications.
*/
/* Are 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, might not exist */
obj_desc = acpi_ns_get_attached_object(node);
if (!obj_desc) {
/* 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, remove local reference */
status = acpi_ns_attach_object(device, obj_desc, node->type);
acpi_ut_remove_reference(obj_desc);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
}
/* Ensure that the handler is not already installed in the lists */
for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
if (handler_type & (i + 1)) {
handler_obj = obj_desc->common_notify.notify_list[i];
while (handler_obj) {
if (handler_obj->notify.handler == handler) {
status = AE_ALREADY_EXISTS;
goto unlock_and_exit;
}
handler_obj = handler_obj->notify.next[i];
}
}
}
/* Create and populate a new notify handler object */
handler_obj = acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_NOTIFY);
if (!handler_obj) {
status = AE_NO_MEMORY;
goto unlock_and_exit;
}
handler_obj->notify.node = node;
handler_obj->notify.handler_type = handler_type;
handler_obj->notify.handler = handler;
handler_obj->notify.context = context;
/* Install the handler at the list head(s) */
for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
if (handler_type & (i + 1)) {
handler_obj->notify.next[i] =
obj_desc->common_notify.notify_list[i];
obj_desc->common_notify.notify_list[i] = handler_obj;
}
}
/* Add an extra reference if handler was installed in both lists */
if (handler_type == ACPI_ALL_NOTIFY) {
acpi_ut_add_reference(handler_obj);
}
unlock_and_exit:
(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_install_notify_handler)
/*******************************************************************************
*
* FUNCTION: acpi_remove_notify_handler
*
* PARAMETERS: device - The device for which the handler is installed
* handler_type - The type of handler:
* ACPI_SYSTEM_NOTIFY: System Handler (00-7F)
* ACPI_DEVICE_NOTIFY: Device 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
*
******************************************************************************/
acpi_status
acpi_remove_notify_handler(acpi_handle device,
u32 handler_type, acpi_notify_handler handler)
{
struct acpi_namespace_node *node =
ACPI_CAST_PTR(struct acpi_namespace_node, device);
union acpi_operand_object *obj_desc;
union acpi_operand_object *handler_obj;
union acpi_operand_object *previous_handler_obj;
acpi_status status = AE_OK;
u32 i;
ACPI_FUNCTION_TRACE(acpi_remove_notify_handler);
/* Parameter validation */
if ((!device) || (!handler) || (!handler_type) ||
(handler_type > ACPI_MAX_NOTIFY_HANDLER_TYPE)) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/* Root Object. Global handlers are removed here */
if (device == ACPI_ROOT_OBJECT) {
for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
if (handler_type & (i + 1)) {
status =
acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
if (!acpi_gbl_global_notify[i].handler ||
(acpi_gbl_global_notify[i].handler !=
handler)) {
status = AE_NOT_EXIST;
goto unlock_and_exit;
}
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Removing global notify handler\n"));
acpi_gbl_global_notify[i].handler = NULL;
acpi_gbl_global_notify[i].context = NULL;
(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
/* Make sure all deferred notify tasks are completed */
acpi_os_wait_events_complete();
}
}
return_ACPI_STATUS(AE_OK);
}
/* All other objects: Are Notifies allowed on this object? */
if (!acpi_ev_is_notify_object(node)) {
return_ACPI_STATUS(AE_TYPE);
}
/* Must have an existing internal object */
obj_desc = acpi_ns_get_attached_object(node);
if (!obj_desc) {
return_ACPI_STATUS(AE_NOT_EXIST);
}
/* Internal object exists. Find the handler and remove it */
for (i = 0; i < ACPI_NUM_NOTIFY_TYPES; i++) {
if (handler_type & (i + 1)) {
status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
handler_obj = obj_desc->common_notify.notify_list[i];
previous_handler_obj = NULL;
/* Attempt to find the handler in the handler list */
while (handler_obj &&
(handler_obj->notify.handler != handler)) {
previous_handler_obj = handler_obj;
handler_obj = handler_obj->notify.next[i];
}
if (!handler_obj) {
status = AE_NOT_EXIST;
goto unlock_and_exit;
}
/* Remove the handler object from the list */
if (previous_handler_obj) { /* Handler is not at the list head */
previous_handler_obj->notify.next[i] =
handler_obj->notify.next[i];
} else { /* Handler is at the list head */
obj_desc->common_notify.notify_list[i] =
handler_obj->notify.next[i];
}
(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
/* Make sure all deferred notify tasks are completed */
acpi_os_wait_events_complete();
acpi_ut_remove_reference(handler_obj);
}
}
return_ACPI_STATUS(status);
unlock_and_exit:
(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_remove_notify_handler)
/*******************************************************************************
*
* 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);
}
ACPI_EXPORT_SYMBOL(acpi_install_exception_handler)
#endif /* ACPI_FUTURE_USAGE */
#if (!ACPI_REDUCED_HARDWARE)
/*******************************************************************************
*
* FUNCTION: acpi_install_sci_handler
*
* PARAMETERS: address - Address of the handler
* context - Value passed to the handler on each SCI
*
* RETURN: Status
*
* DESCRIPTION: Install a handler for a System Control Interrupt.
*
******************************************************************************/
acpi_status acpi_install_sci_handler(acpi_sci_handler address, void *context)
{
struct acpi_sci_handler_info *new_sci_handler;
struct acpi_sci_handler_info *sci_handler;
acpi_cpu_flags flags;
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_install_sci_handler);
if (!address) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/* Allocate and init a handler object */
new_sci_handler = ACPI_ALLOCATE(sizeof(struct acpi_sci_handler_info));
if (!new_sci_handler) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
new_sci_handler->address = address;
new_sci_handler->context = context;
status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
if (ACPI_FAILURE(status)) {
goto exit;
}
/* Lock list during installation */
flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
sci_handler = acpi_gbl_sci_handler_list;
/* Ensure handler does not already exist */
while (sci_handler) {
if (address == sci_handler->address) {
status = AE_ALREADY_EXISTS;
goto unlock_and_exit;
}
sci_handler = sci_handler->next;
}
/* Install the new handler into the global list (at head) */
new_sci_handler->next = acpi_gbl_sci_handler_list;
acpi_gbl_sci_handler_list = new_sci_handler;
unlock_and_exit:
acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
exit:
if (ACPI_FAILURE(status)) {
ACPI_FREE(new_sci_handler);
}
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_install_sci_handler)
/*******************************************************************************
*
* FUNCTION: acpi_remove_sci_handler
*
* PARAMETERS: address - Address of the handler
*
* RETURN: Status
*
* DESCRIPTION: Remove a handler for a System Control Interrupt.
*
******************************************************************************/
acpi_status acpi_remove_sci_handler(acpi_sci_handler address)
{
struct acpi_sci_handler_info *prev_sci_handler;
struct acpi_sci_handler_info *next_sci_handler;
acpi_cpu_flags flags;
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_remove_sci_handler);
if (!address) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Remove the SCI handler with lock */
flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
prev_sci_handler = NULL;
next_sci_handler = acpi_gbl_sci_handler_list;
while (next_sci_handler) {
if (next_sci_handler->address == address) {
/* Unlink and free the SCI handler info block */
if (prev_sci_handler) {
prev_sci_handler->next = next_sci_handler->next;
} else {
acpi_gbl_sci_handler_list =
next_sci_handler->next;
}
acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
ACPI_FREE(next_sci_handler);
goto unlock_and_exit;
}
prev_sci_handler = next_sci_handler;
next_sci_handler = next_sci_handler->next;
}
acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
status = AE_NOT_EXIST;
unlock_and_exit:
(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_remove_sci_handler)
/*******************************************************************************
*
* FUNCTION: acpi_install_global_event_handler
*
* PARAMETERS: handler - Pointer to the global event handler function
* context - Value passed to the handler on each event
*
* RETURN: Status
*
* DESCRIPTION: Saves the pointer to the handler function. The global handler
* is invoked upon each incoming GPE and Fixed Event. It is
* invoked at interrupt level at the time of the event dispatch.
* Can be used to update event counters, etc.
*
******************************************************************************/
acpi_status
acpi_install_global_event_handler(acpi_gbl_event_handler handler, void *context)
{
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_install_global_event_handler);
/* Parameter validation */
if (!handler) {
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 (acpi_gbl_global_event_handler) {
status = AE_ALREADY_EXISTS;
goto cleanup;
}
acpi_gbl_global_event_handler = handler;
acpi_gbl_global_event_handler_context = context;
cleanup:
(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_install_global_event_handler)
/*******************************************************************************
*
* 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);
}
/* Do not allow multiple handlers */
if (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_WARNING((AE_INFO,
"Could not enable fixed event - %s (%u)",
acpi_ut_get_event_name(event), event));
/* 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 %s (%X), Handler=%p\n",
acpi_ut_get_event_name(event), event,
handler));
}
cleanup:
(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
return_ACPI_STATUS(status);
}
ACPI_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_WARNING((AE_INFO,
"Could not disable fixed event - %s (%u)",
acpi_ut_get_event_name(event), event));
} else {
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Disabled fixed event - %s (%X)\n",
acpi_ut_get_event_name(event), event));
}
(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_remove_fixed_event_handler)
/*******************************************************************************
*
* FUNCTION: acpi_install_gpe_handler
*
* PARAMETERS: gpe_device - Namespace node for the GPE (NULL for FADT
* defined GPEs)
* gpe_number - The GPE number within the GPE block
* type - Whether this GPE should be treated as an
* edge- or level-triggered interrupt.
* address - Address of the handler
* context - Value passed to the handler on each GPE
*
* RETURN: Status
*
* DESCRIPTION: Install a handler for a General Purpose Event.
*
******************************************************************************/
acpi_status
acpi_install_gpe_handler(acpi_handle gpe_device,
u32 gpe_number,
u32 type, acpi_gpe_handler address, void *context)
{
struct acpi_gpe_event_info *gpe_event_info;
struct acpi_gpe_handler_info *handler;
acpi_status status;
acpi_cpu_flags flags;
ACPI_FUNCTION_TRACE(acpi_install_gpe_handler);
/* Parameter validation */
if ((!address) || (type & ~ACPI_GPE_XRUPT_TYPE_MASK)) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Allocate and init handler object (before lock) */
handler = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_gpe_handler_info));
if (!handler) {
status = AE_NO_MEMORY;
goto unlock_and_exit;
}
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 free_and_exit;
}
/* Make sure that there isn't a handler there already */
if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
ACPI_GPE_DISPATCH_HANDLER) {
status = AE_ALREADY_EXISTS;
goto free_and_exit;
}
handler->address = address;
handler->context = context;
handler->method_node = gpe_event_info->dispatch.method_node;
handler->original_flags = (u8)(gpe_event_info->flags &
(ACPI_GPE_XRUPT_TYPE_MASK |
ACPI_GPE_DISPATCH_MASK));
/*
* If the GPE is associated with a method, it may have been enabled
* automatically during initialization, in which case it has to be
* disabled now to avoid spurious execution of the handler.
*/
if ((handler->original_flags & ACPI_GPE_DISPATCH_METHOD)
&& gpe_event_info->runtime_count) {
handler->originally_enabled = 1;
(void)acpi_ev_remove_gpe_reference(gpe_event_info);
}
/* Install the handler */
gpe_event_info->dispatch.handler = handler;
/* Setup up dispatch flags to indicate handler (vs. method/notify) */
gpe_event_info->flags &=
~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);
gpe_event_info->flags |= (u8) (type | ACPI_GPE_DISPATCH_HANDLER);
acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
unlock_and_exit:
(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
return_ACPI_STATUS(status);
free_and_exit:
acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
ACPI_FREE(handler);
goto unlock_and_exit;
}
ACPI_EXPORT_SYMBOL(acpi_install_gpe_handler)
/*******************************************************************************
*
* FUNCTION: acpi_remove_gpe_handler
*
* PARAMETERS: gpe_device - Namespace node for the GPE (NULL for FADT
* defined GPEs)
* gpe_number - The event to remove a handler
* address - Address of the handler
*
* RETURN: Status
*
* DESCRIPTION: Remove a handler for a General Purpose acpi_event.
*
******************************************************************************/
acpi_status
acpi_remove_gpe_handler(acpi_handle gpe_device,
u32 gpe_number, acpi_gpe_handler address)
{
struct acpi_gpe_event_info *gpe_event_info;
struct acpi_gpe_handler_info *handler;
acpi_status status;
acpi_cpu_flags flags;
ACPI_FUNCTION_TRACE(acpi_remove_gpe_handler);
/* Parameter validation */
if (!address) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
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;
}
/* Make sure that a handler is indeed installed */
if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) !=
ACPI_GPE_DISPATCH_HANDLER) {
status = AE_NOT_EXIST;
goto unlock_and_exit;
}
/* Make sure that the installed handler is the same */
if (gpe_event_info->dispatch.handler->address != address) {
status = AE_BAD_PARAMETER;
goto unlock_and_exit;
}
/* Remove the handler */
handler = gpe_event_info->dispatch.handler;
/* Restore Method node (if any), set dispatch flags */
gpe_event_info->dispatch.method_node = handler->method_node;
gpe_event_info->flags &=
~(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK);
gpe_event_info->flags |= handler->original_flags;
/*
* If the GPE was previously associated with a method and it was
* enabled, it should be enabled at this point to restore the
* post-initialization configuration.
*/
if ((handler->original_flags & ACPI_GPE_DISPATCH_METHOD) &&
handler->originally_enabled) {
(void)acpi_ev_add_gpe_reference(gpe_event_info);
}
acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
/* Make sure all deferred GPE tasks are completed */
acpi_os_wait_events_complete();
/* Now we can free the handler object */
ACPI_FREE(handler);
return_ACPI_STATUS(status);
unlock_and_exit:
acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_remove_gpe_handler)
/*******************************************************************************
*
* FUNCTION: acpi_acquire_global_lock
*
* PARAMETERS: timeout - How long the caller is willing to wait
* handle - Where the handle to the lock is returned
* (if acquired)
*
* RETURN: Status
*
* DESCRIPTION: Acquire the ACPI Global Lock
*
* Note: Allows callers with the same thread ID to acquire the global lock
* multiple times. In other words, externally, the behavior of the global lock
* is identical to an AML mutex. On the first acquire, a new handle is
* returned. On any subsequent calls to acquire by the same thread, the same
* handle is returned.
*
******************************************************************************/
acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle)
{
acpi_status status;
if (!handle) {
return (AE_BAD_PARAMETER);
}
/* Must lock interpreter to prevent race conditions */
acpi_ex_enter_interpreter();
status = acpi_ex_acquire_mutex_object(timeout,
acpi_gbl_global_lock_mutex,
acpi_os_get_thread_id());
if (ACPI_SUCCESS(status)) {
/* Return the global lock handle (updated in acpi_ev_acquire_global_lock) */
*handle = acpi_gbl_global_lock_handle;
}
acpi_ex_exit_interpreter();
return (status);
}
ACPI_EXPORT_SYMBOL(acpi_acquire_global_lock)
/*******************************************************************************
*
* FUNCTION: acpi_release_global_lock
*
* PARAMETERS: handle - Returned from acpi_acquire_global_lock
*
* RETURN: Status
*
* DESCRIPTION: Release the ACPI Global Lock. The handle must be valid.
*
******************************************************************************/
acpi_status acpi_release_global_lock(u32 handle)
{
acpi_status status;
if (!handle || (handle != acpi_gbl_global_lock_handle)) {
return (AE_NOT_ACQUIRED);
}
status = acpi_ex_release_mutex_object(acpi_gbl_global_lock_mutex);
return (status);
}
ACPI_EXPORT_SYMBOL(acpi_release_global_lock)
#endif /* !ACPI_REDUCED_HARDWARE */