linux/drivers/acpi/acpica/evgpe.c
Lin Ming da50337373 ACPICA: Misc comments to minimize code divergence
Modify/add some comments to minimize ACPICA/linux GPE code divergence.

Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2011-01-12 04:27:00 -05:00

749 lines
21 KiB
C

/******************************************************************************
*
* Module Name: evgpe - General Purpose Event handling and dispatch
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2010, 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.
*/
#include <acpi/acpi.h>
#include "accommon.h"
#include "acevents.h"
#include "acnamesp.h"
#define _COMPONENT ACPI_EVENTS
ACPI_MODULE_NAME("evgpe")
/* Local prototypes */
static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context);
static void ACPI_SYSTEM_XFACE acpi_ev_asynch_enable_gpe(void *context);
/*******************************************************************************
*
* FUNCTION: acpi_ev_update_gpe_enable_mask
*
* PARAMETERS: gpe_event_info - GPE to update
*
* RETURN: Status
*
* DESCRIPTION: Updates GPE register enable mask based upon whether there are
* runtime references to this GPE
*
******************************************************************************/
acpi_status
acpi_ev_update_gpe_enable_mask(struct acpi_gpe_event_info *gpe_event_info)
{
struct acpi_gpe_register_info *gpe_register_info;
u32 register_bit;
ACPI_FUNCTION_TRACE(ev_update_gpe_enable_mask);
gpe_register_info = gpe_event_info->register_info;
if (!gpe_register_info) {
return_ACPI_STATUS(AE_NOT_EXIST);
}
register_bit = acpi_hw_get_gpe_register_bit(gpe_event_info,
gpe_register_info);
/* Clear the run bit up front */
ACPI_CLEAR_BIT(gpe_register_info->enable_for_run, register_bit);
/* Set the mask bit only if there are references to this GPE */
if (gpe_event_info->runtime_count) {
ACPI_SET_BIT(gpe_register_info->enable_for_run, (u8)register_bit);
}
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_enable_gpe
*
* PARAMETERS: gpe_event_info - GPE to enable
*
* RETURN: Status
*
* DESCRIPTION: Clear a GPE of stale events and enable it.
*
******************************************************************************/
acpi_status
acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info)
{
acpi_status status;
ACPI_FUNCTION_TRACE(ev_enable_gpe);
/*
* We will only allow a GPE to be enabled if it has either an associated
* method (_Lxx/_Exx) or a handler, or is using the implicit notify
* feature. Otherwise, the GPE will be immediately disabled by
* acpi_ev_gpe_dispatch the first time it fires.
*/
if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
ACPI_GPE_DISPATCH_NONE) {
return_ACPI_STATUS(AE_NO_HANDLER);
}
/* Clear the GPE (of stale events) */
status = acpi_hw_clear_gpe(gpe_event_info);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Enable the requested GPE */
status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_ENABLE);
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_add_gpe_reference
*
* PARAMETERS: gpe_event_info - Add a reference to this GPE
*
* RETURN: Status
*
* DESCRIPTION: Add a reference to a GPE. On the first reference, the GPE is
* hardware-enabled.
*
******************************************************************************/
acpi_status acpi_ev_add_gpe_reference(struct acpi_gpe_event_info *gpe_event_info)
{
acpi_status status = AE_OK;
ACPI_FUNCTION_TRACE(ev_add_gpe_reference);
if (gpe_event_info->runtime_count == ACPI_UINT8_MAX) {
return_ACPI_STATUS(AE_LIMIT);
}
gpe_event_info->runtime_count++;
if (gpe_event_info->runtime_count == 1) {
/* Enable on first reference */
status = acpi_ev_update_gpe_enable_mask(gpe_event_info);
if (ACPI_SUCCESS(status)) {
status = acpi_ev_enable_gpe(gpe_event_info);
}
if (ACPI_FAILURE(status)) {
gpe_event_info->runtime_count--;
}
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_remove_gpe_reference
*
* PARAMETERS: gpe_event_info - Remove a reference to this GPE
*
* RETURN: Status
*
* DESCRIPTION: Remove a reference to a GPE. When the last reference is
* removed, the GPE is hardware-disabled.
*
******************************************************************************/
acpi_status acpi_ev_remove_gpe_reference(struct acpi_gpe_event_info *gpe_event_info)
{
acpi_status status = AE_OK;
ACPI_FUNCTION_TRACE(ev_remove_gpe_reference);
if (!gpe_event_info->runtime_count) {
return_ACPI_STATUS(AE_LIMIT);
}
gpe_event_info->runtime_count--;
if (!gpe_event_info->runtime_count) {
/* Disable on last reference */
status = acpi_ev_update_gpe_enable_mask(gpe_event_info);
if (ACPI_SUCCESS(status)) {
status = acpi_hw_low_set_gpe(gpe_event_info,
ACPI_GPE_DISABLE);
}
if (ACPI_FAILURE(status)) {
gpe_event_info->runtime_count++;
}
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_low_get_gpe_info
*
* PARAMETERS: gpe_number - Raw GPE number
* gpe_block - A GPE info block
*
* RETURN: A GPE event_info struct. NULL if not a valid GPE (The gpe_number
* is not within the specified GPE block)
*
* DESCRIPTION: Returns the event_info struct associated with this GPE. This is
* the low-level implementation of ev_get_gpe_event_info.
*
******************************************************************************/
struct acpi_gpe_event_info *acpi_ev_low_get_gpe_info(u32 gpe_number,
struct acpi_gpe_block_info
*gpe_block)
{
u32 gpe_index;
/*
* Validate that the gpe_number is within the specified gpe_block.
* (Two steps)
*/
if (!gpe_block || (gpe_number < gpe_block->block_base_number)) {
return (NULL);
}
gpe_index = gpe_number - gpe_block->block_base_number;
if (gpe_index >= gpe_block->gpe_count) {
return (NULL);
}
return (&gpe_block->event_info[gpe_index]);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_get_gpe_event_info
*
* PARAMETERS: gpe_device - Device node. NULL for GPE0/GPE1
* gpe_number - Raw GPE number
*
* RETURN: A GPE event_info struct. NULL if not a valid GPE
*
* DESCRIPTION: Returns the event_info struct associated with this GPE.
* Validates the gpe_block and the gpe_number
*
* Should be called only when the GPE lists are semaphore locked
* and not subject to change.
*
******************************************************************************/
struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
u32 gpe_number)
{
union acpi_operand_object *obj_desc;
struct acpi_gpe_event_info *gpe_info;
u32 i;
ACPI_FUNCTION_ENTRY();
/* A NULL gpe_device means use the FADT-defined GPE block(s) */
if (!gpe_device) {
/* Examine GPE Block 0 and 1 (These blocks are permanent) */
for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++) {
gpe_info = acpi_ev_low_get_gpe_info(gpe_number,
acpi_gbl_gpe_fadt_blocks
[i]);
if (gpe_info) {
return (gpe_info);
}
}
/* The gpe_number was not in the range of either FADT GPE block */
return (NULL);
}
/* A Non-NULL gpe_device means this is a GPE Block Device */
obj_desc = acpi_ns_get_attached_object((struct acpi_namespace_node *)
gpe_device);
if (!obj_desc || !obj_desc->device.gpe_block) {
return (NULL);
}
return (acpi_ev_low_get_gpe_info
(gpe_number, obj_desc->device.gpe_block));
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_gpe_detect
*
* PARAMETERS: gpe_xrupt_list - Interrupt block for this interrupt.
* Can have multiple GPE blocks attached.
*
* RETURN: INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
*
* DESCRIPTION: Detect if any GP events have occurred. This function is
* executed at interrupt level.
*
******************************************************************************/
u32 acpi_ev_gpe_detect(struct acpi_gpe_xrupt_info * gpe_xrupt_list)
{
acpi_status status;
struct acpi_gpe_block_info *gpe_block;
struct acpi_gpe_register_info *gpe_register_info;
u32 int_status = ACPI_INTERRUPT_NOT_HANDLED;
u8 enabled_status_byte;
u32 status_reg;
u32 enable_reg;
acpi_cpu_flags flags;
u32 i;
u32 j;
ACPI_FUNCTION_NAME(ev_gpe_detect);
/* Check for the case where there are no GPEs */
if (!gpe_xrupt_list) {
return (int_status);
}
/*
* We need to obtain the GPE lock for both the data structs and registers
* Note: Not necessary to obtain the hardware lock, since the GPE
* registers are owned by the gpe_lock.
*/
flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
/* Examine all GPE blocks attached to this interrupt level */
gpe_block = gpe_xrupt_list->gpe_block_list_head;
while (gpe_block) {
/*
* Read all of the 8-bit GPE status and enable registers in this GPE
* block, saving all of them. Find all currently active GP events.
*/
for (i = 0; i < gpe_block->register_count; i++) {
/* Get the next status/enable pair */
gpe_register_info = &gpe_block->register_info[i];
/* Read the Status Register */
status =
acpi_hw_read(&status_reg,
&gpe_register_info->status_address);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
/* Read the Enable Register */
status =
acpi_hw_read(&enable_reg,
&gpe_register_info->enable_address);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
"Read GPE Register at GPE%02X: Status=%02X, Enable=%02X\n",
gpe_register_info->base_gpe_number,
status_reg, enable_reg));
/* Check if there is anything active at all in this register */
enabled_status_byte = (u8) (status_reg & enable_reg);
if (!enabled_status_byte) {
/* No active GPEs in this register, move on */
continue;
}
/* Now look at the individual GPEs in this byte register */
for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
/* Examine one GPE bit */
if (enabled_status_byte & (1 << j)) {
/*
* Found an active GPE. Dispatch the event to a handler
* or method.
*/
int_status |=
acpi_ev_gpe_dispatch(gpe_block->
node,
&gpe_block->
event_info[((acpi_size) i * ACPI_GPE_REGISTER_WIDTH) + j], j + gpe_register_info->base_gpe_number);
}
}
}
gpe_block = gpe_block->next;
}
unlock_and_exit:
acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
return (int_status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_asynch_execute_gpe_method
*
* PARAMETERS: Context (gpe_event_info) - Info for this GPE
*
* RETURN: None
*
* DESCRIPTION: Perform the actual execution of a GPE control method. This
* function is called from an invocation of acpi_os_execute and
* therefore does NOT execute at interrupt level - so that
* the control method itself is not executed in the context of
* an interrupt handler.
*
******************************************************************************/
static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
{
struct acpi_gpe_event_info *gpe_event_info = context;
acpi_status status;
struct acpi_gpe_event_info *local_gpe_event_info;
struct acpi_evaluate_info *info;
ACPI_FUNCTION_TRACE(ev_asynch_execute_gpe_method);
/* Allocate a local GPE block */
local_gpe_event_info =
ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_gpe_event_info));
if (!local_gpe_event_info) {
ACPI_EXCEPTION((AE_INFO, AE_NO_MEMORY, "while handling a GPE"));
return_VOID;
}
status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
if (ACPI_FAILURE(status)) {
return_VOID;
}
/* Must revalidate the gpe_number/gpe_block */
if (!acpi_ev_valid_gpe_event(gpe_event_info)) {
status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
return_VOID;
}
/*
* Take a snapshot of the GPE info for this level - we copy the info to
* prevent a race condition with remove_handler/remove_block.
*/
ACPI_MEMCPY(local_gpe_event_info, gpe_event_info,
sizeof(struct acpi_gpe_event_info));
status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
if (ACPI_FAILURE(status)) {
return_VOID;
}
/* Do the correct dispatch - normal method or implicit notify */
switch (local_gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) {
case ACPI_GPE_DISPATCH_NOTIFY:
/*
* Implicit notify.
* Dispatch a DEVICE_WAKE notify to the appropriate handler.
* NOTE: the request is queued for execution after this method
* completes. The notify handlers are NOT invoked synchronously
* from this thread -- because handlers may in turn run other
* control methods.
*/
status =
acpi_ev_queue_notify_request(local_gpe_event_info->dispatch.
device_node,
ACPI_NOTIFY_DEVICE_WAKE);
break;
case ACPI_GPE_DISPATCH_METHOD:
/* Allocate the evaluation information block */
info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
if (!info) {
status = AE_NO_MEMORY;
} else {
/*
* Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the _Lxx/_Exx
* control method that corresponds to this GPE
*/
info->prefix_node =
local_gpe_event_info->dispatch.method_node;
info->flags = ACPI_IGNORE_RETURN_VALUE;
status = acpi_ns_evaluate(info);
ACPI_FREE(info);
}
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"while evaluating GPE method [%4.4s]",
acpi_ut_get_node_name
(local_gpe_event_info->dispatch.
method_node)));
}
break;
default:
return_VOID; /* Should never happen */
}
/* Defer enabling of GPE until all notify handlers are done */
status = acpi_os_execute(OSL_NOTIFY_HANDLER,
acpi_ev_asynch_enable_gpe,
local_gpe_event_info);
if (ACPI_FAILURE(status)) {
ACPI_FREE(local_gpe_event_info);
}
return_VOID;
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_asynch_enable_gpe
*
* PARAMETERS: Context (gpe_event_info) - Info for this GPE
* Callback from acpi_os_execute
*
* RETURN: None
*
* DESCRIPTION: Asynchronous clear/enable for GPE. This allows the GPE to
* complete (i.e., finish execution of Notify)
*
******************************************************************************/
static void ACPI_SYSTEM_XFACE acpi_ev_asynch_enable_gpe(void *context)
{
struct acpi_gpe_event_info *gpe_event_info = context;
(void)acpi_ev_finish_gpe(gpe_event_info);
ACPI_FREE(gpe_event_info);
return;
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_finish_gpe
*
* PARAMETERS: gpe_event_info - Info for this GPE
*
* RETURN: Status
*
* DESCRIPTION: Clear/Enable a GPE. Common code that is used after execution
* of a GPE method or a synchronous or asynchronous GPE handler.
*
******************************************************************************/
acpi_status acpi_ev_finish_gpe(struct acpi_gpe_event_info *gpe_event_info)
{
acpi_status status;
if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
ACPI_GPE_LEVEL_TRIGGERED) {
/*
* GPE is level-triggered, we clear the GPE status bit after
* handling the event.
*/
status = acpi_hw_clear_gpe(gpe_event_info);
if (ACPI_FAILURE(status)) {
return (status);
}
}
/*
* Enable this GPE, conditionally. This means that the GPE will
* only be physically enabled if the enable_for_run bit is set
* in the event_info.
*/
(void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_CONDITIONAL_ENABLE);
return (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ev_gpe_dispatch
*
* PARAMETERS: gpe_device - Device node. NULL for GPE0/GPE1
* gpe_event_info - Info for this GPE
* gpe_number - Number relative to the parent GPE block
*
* RETURN: INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
*
* DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
* or method (e.g. _Lxx/_Exx) handler.
*
* This function executes at interrupt level.
*
******************************************************************************/
u32
acpi_ev_gpe_dispatch(struct acpi_namespace_node *gpe_device,
struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
{
acpi_status status;
u32 return_value;
ACPI_FUNCTION_TRACE(ev_gpe_dispatch);
/* Invoke global event handler if present */
acpi_gpe_count++;
if (acpi_gbl_global_event_handler) {
acpi_gbl_global_event_handler(ACPI_EVENT_TYPE_GPE, gpe_device,
gpe_number,
acpi_gbl_global_event_handler_context);
}
/*
* If edge-triggered, clear the GPE status bit now. Note that
* level-triggered events are cleared after the GPE is serviced.
*/
if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
ACPI_GPE_EDGE_TRIGGERED) {
status = acpi_hw_clear_gpe(gpe_event_info);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"Unable to clear GPE%02X", gpe_number));
return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
}
}
/*
* Always disable the GPE so that it does not keep firing before
* any asynchronous activity completes (either from the execution
* of a GPE method or an asynchronous GPE handler.)
*
* If there is no handler or method to run, just disable the
* GPE and leave it disabled permanently to prevent further such
* pointless events from firing.
*/
status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"Unable to disable GPE%02X", gpe_number));
return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
}
/*
* Dispatch the GPE to either an installed handler or the control
* method associated with this GPE (_Lxx or _Exx). If a handler
* exists, we invoke it and do not attempt to run the method.
* If there is neither a handler nor a method, leave the GPE
* disabled.
*/
switch (gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) {
case ACPI_GPE_DISPATCH_HANDLER:
/* Invoke the installed handler (at interrupt level) */
return_value =
gpe_event_info->dispatch.handler->address(gpe_device,
gpe_number,
gpe_event_info->
dispatch.handler->
context);
/* If requested, clear (if level-triggered) and reenable the GPE */
if (return_value & ACPI_REENABLE_GPE) {
(void)acpi_ev_finish_gpe(gpe_event_info);
}
break;
case ACPI_GPE_DISPATCH_METHOD:
case ACPI_GPE_DISPATCH_NOTIFY:
/*
* Execute the method associated with the GPE
* NOTE: Level-triggered GPEs are cleared after the method completes.
*/
status = acpi_os_execute(OSL_GPE_HANDLER,
acpi_ev_asynch_execute_gpe_method,
gpe_event_info);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"Unable to queue handler for GPE%2X - event disabled",
gpe_number));
}
break;
default:
/*
* No handler or method to run!
* 03/2010: This case should no longer be possible. We will not allow
* a GPE to be enabled if it has no handler or method.
*/
ACPI_ERROR((AE_INFO,
"No handler or method for GPE%02X, disabling event",
gpe_number));
break;
}
return_UINT32(ACPI_INTERRUPT_HANDLED);
}