power.c

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/*
 *  acpi_power.c - ACPI Bus Power Management ($Revision: 39 $)
 *
 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  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.
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */

/*
 * ACPI power-managed devices may be controlled in two ways:
 * 1. via "Device Specific (D-State) Control"
 * 2. via "Power Resource Control".
 * This module is used to manage devices relying on Power Resource Control.
 * 
 * An ACPI "power resource object" describes a software controllable power
 * plane, clock plane, or other resource used by a power managed device.
 * A device may rely on multiple power resources, and a power resource
 * may be shared by multiple devices.
 */

/*
 * Modified for ReactOS and latest ACPICA
 * Copyright (C)2009  Samuel Serapion 
 */

#include <ntddk.h>
#include <acpi.h>
#include <acpi_bus.h>
#include <acpi_drivers.h>
#include <glue.h>

#define NDEBUG
#include <debug.h>


#define _COMPONENT      ACPI_POWER_COMPONENT
ACPI_MODULE_NAME        ("acpi_power")

#define ACPI_POWER_RESOURCE_STATE_OFF   0x00
#define ACPI_POWER_RESOURCE_STATE_ON    0x01
#define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF

int acpi_power_nocheck;

static int acpi_power_add (struct acpi_device *device);
static int acpi_power_remove (struct acpi_device *device, int type);
static int acpi_power_resume(struct acpi_device *device, int state);

static struct acpi_driver acpi_power_driver = {
    {0,0},
    ACPI_POWER_DRIVER_NAME,
    ACPI_POWER_CLASS,
    0,
    0,
    ACPI_POWER_HID,
    {acpi_power_add, acpi_power_remove, NULL, NULL, acpi_power_resume}
};

struct acpi_power_reference {
    struct list_head node;
    struct acpi_device *device;
};

struct acpi_power_resource
{
    struct acpi_device * device;
    acpi_bus_id     name;
    UINT32          system_level;
    UINT32          order;
    //struct mutex resource_lock;
    struct list_head reference;
};

static struct list_head     acpi_power_resource_list;


/* --------------------------------------------------------------------------
                             Power Resource Management
   -------------------------------------------------------------------------- */

static int
acpi_power_get_context (
    ACPI_HANDLE     handle,
    struct acpi_power_resource **resource)
{
    int         result = 0;
    struct acpi_device  *device = NULL;

    if (!resource)
        return_VALUE(-15);

    result = acpi_bus_get_device(handle, &device);
    if (result) {
        ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Error getting context [%p]\n",
            handle));
        return_VALUE(result);
    }

    *resource = (struct acpi_power_resource *) acpi_driver_data(device);
    if (!*resource)
        return_VALUE(-15);

    return 0;
}


static int
acpi_power_get_state (
    ACPI_HANDLE handle,
    int *state)
{
    ACPI_STATUS     status = AE_OK;
    unsigned long long  sta = 0;
    char node_name[5];
    ACPI_BUFFER buffer = { sizeof(node_name), node_name };


    if (!handle || !state)
        return_VALUE(-1);

    status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
    if (ACPI_FAILURE(status))
        return_VALUE(-15);

    *state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:
                  ACPI_POWER_RESOURCE_STATE_OFF;

    AcpiGetName(handle, ACPI_SINGLE_NAME, &buffer);

    ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
        node_name, *state?"on":"off"));

    return 0;
}


static int
acpi_power_get_list_state (
    struct acpi_handle_list *list,
    int         *state)
{
    int result = 0, state1;
    UINT32 i = 0;

    if (!list || !state)
        return_VALUE(-1);

    /* The state of the list is 'on' IFF all resources are 'on'. */

    for (i=0; i<list->count; i++) {
        /*
         * The state of the power resource can be obtained by
         * using the ACPI handle. In such case it is unnecessary to
         * get the Power resource first and then get its state again.
         */
        result = acpi_power_get_state(list->handles[i], &state1);
        if (result)
            return result;

        *state = state1;

        if (*state != ACPI_POWER_RESOURCE_STATE_ON)
            break;
    }

    ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n",
        *state?"on":"off"));

    return result;
}


static int
acpi_power_on (
    ACPI_HANDLE handle, struct acpi_device *dev)
{
    int result = 0;
    int found = 0;
    ACPI_STATUS status = AE_OK;
    struct acpi_power_resource *resource = NULL;
    struct list_head *node, *next;
    struct acpi_power_reference *ref;

    result = acpi_power_get_context(handle, &resource);
    if (result)
        return result;

    //mutex_lock(&resource->resource_lock);
    list_for_each_safe(node, next, &resource->reference) {
        ref = container_of(node, struct acpi_power_reference, node);
        if (dev->handle == ref->device->handle) {
            ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already referenced by resource [%s]\n",
                  dev->pnp.bus_id, resource->name));
            found = 1;
            break;
        }
    }

    if (!found) {
        ref = ExAllocatePoolWithTag(NonPagedPool,sizeof (struct acpi_power_reference),'IPCA');
        if (!ref) {
            ACPI_DEBUG_PRINT((ACPI_DB_INFO, "kmalloc() failed\n"));
            //mutex_unlock(&resource->resource_lock);
            return -1;//-ENOMEM;
        }
        list_add_tail(&ref->node, &resource->reference);
        ref->device = dev;
        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] added to resource [%s] references\n",
              dev->pnp.bus_id, resource->name));
    }
    //mutex_unlock(&resource->resource_lock);

    status = AcpiEvaluateObject(resource->device->handle, "_ON", NULL, NULL);
    if (ACPI_FAILURE(status))
        return_VALUE(-15);

    /* Update the power resource's _device_ power state */
    resource->device->power.state = ACPI_STATE_D0;

    return 0;
}


static int
acpi_power_off_device (
    ACPI_HANDLE handle,
    struct acpi_device *dev)
{
    int result = 0;
    ACPI_STATUS status = AE_OK;
    struct acpi_power_resource *resource = NULL;
    struct list_head *node, *next;
    struct acpi_power_reference *ref;

    result = acpi_power_get_context(handle, &resource);
    if (result)
        return result;

    //mutex_lock(&resource->resource_lock);
    list_for_each_safe(node, next, &resource->reference) {
        ref = container_of(node, struct acpi_power_reference, node);
        if (dev->handle == ref->device->handle) {
            list_del(&ref->node);
            ExFreePool(ref);
            ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] removed from resource [%s] references\n",
                dev->pnp.bus_id, resource->name));
            break;
        }
    }

    if (!list_empty(&resource->reference)) {
        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Cannot turn resource [%s] off - resource is in use\n",
            resource->name));
        //mutex_unlock(&resource->resource_lock);
        return 0;
    }
    //mutex_unlock(&resource->resource_lock);

    status = AcpiEvaluateObject(resource->device->handle, "_OFF", NULL, NULL);
    if (ACPI_FAILURE(status))
        return -1;

    /* Update the power resource's _device_ power state */
    resource->device->power.state = ACPI_STATE_D3;

    ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] turned off\n",
              resource->name));

    return 0;
}

int acpi_device_sleep_wake(struct acpi_device *dev,
                           int enable, int sleep_state, int dev_state)
{
    union acpi_object in_arg[3];
    struct acpi_object_list arg_list = { 3, in_arg };
    ACPI_STATUS status = AE_OK;

    /*
     * Try to execute _DSW first.
     *
     * Three agruments are needed for the _DSW object:
     * Argument 0: enable/disable the wake capabilities
     * Argument 1: target system state
     * Argument 2: target device state
     * When _DSW object is called to disable the wake capabilities, maybe
     * the first argument is filled. The values of the other two agruments
     * are meaningless.
     */
    in_arg[0].Type = ACPI_TYPE_INTEGER;
    in_arg[0].Integer.Value = enable;
    in_arg[1].Type = ACPI_TYPE_INTEGER;
    in_arg[1].Integer.Value = sleep_state;
    in_arg[2].Type = ACPI_TYPE_INTEGER;
    in_arg[2].Integer.Value = dev_state;
    status = AcpiEvaluateObject(dev->handle, "_DSW", &arg_list, NULL);
    if (ACPI_SUCCESS(status)) {
        return 0;
    } else if (status != AE_NOT_FOUND) {
        DPRINT1("_DSW execution failed\n");
        dev->wakeup.flags.valid = 0;
        return -1;
    }

    /* Execute _PSW */
    arg_list.Count = 1;
    in_arg[0].Integer.Value = enable;
    status = AcpiEvaluateObject(dev->handle, "_PSW", &arg_list, NULL);
    if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
        DPRINT1("_PSW execution failed\n");
        dev->wakeup.flags.valid = 0;
        return -1;
    }

    return 0;
}

/*
 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
 * 1. Power on the power resources required for the wakeup device 
 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
 *    State Wake) for the device, if present
 */
int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
{
    int i, err = 0;

    if (!dev || !dev->wakeup.flags.valid)
        return -1;

    //mutex_lock(&acpi_device_lock);

    if (dev->wakeup.prepare_count++)
        goto out;

    /* Open power resource */
    for (i = 0; i < dev->wakeup.resources.count; i++) {
        int ret = acpi_power_on(dev->wakeup.resources.handles[i], dev);
        if (ret) {
            DPRINT( "Transition power state\n");
            dev->wakeup.flags.valid = 0;
            err = -1;
            goto err_out;
        }
    }

    /*
     * Passing 3 as the third argument below means the device may be placed
     * in arbitrary power state afterwards.
     */
    err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);

 err_out:
    if (err)
        dev->wakeup.prepare_count = 0;

 out:
    //mutex_unlock(&acpi_device_lock);
    return err;
}

/*
 * Shutdown a wakeup device, counterpart of above method
 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
 *    State Wake) for the device, if present
 * 2. Shutdown down the power resources
 */
int acpi_disable_wakeup_device_power(struct acpi_device *dev)
{
    int i, err = 0;

    if (!dev || !dev->wakeup.flags.valid)
        return -1;

    //mutex_lock(&acpi_device_lock);

    if (--dev->wakeup.prepare_count > 0)
        goto out;

    /*
     * Executing the code below even if prepare_count is already zero when
     * the function is called may be useful, for example for initialisation.
     */
    if (dev->wakeup.prepare_count < 0)
        dev->wakeup.prepare_count = 0;

    err = acpi_device_sleep_wake(dev, 0, 0, 0);
    if (err)
        goto out;

    /* Close power resource */
    for (i = 0; i < dev->wakeup.resources.count; i++) {
        int ret = acpi_power_off_device(
                dev->wakeup.resources.handles[i], dev);
        if (ret) {
            DPRINT("Transition power state\n");
            dev->wakeup.flags.valid = 0;
            err = -1;
            goto out;
        }
    }

 out:
    //mutex_unlock(&acpi_device_lock);
    return err;
}

/* --------------------------------------------------------------------------
                             Device Power Management
   -------------------------------------------------------------------------- */

int
acpi_power_get_inferred_state (
    struct acpi_device  *device)
{
    int         result = 0;
    struct acpi_handle_list *list = NULL;
    int         list_state = 0;
    int         i = 0;


    if (!device)
        return_VALUE(-1);

    device->power.state = ACPI_STATE_UNKNOWN;

    /*
     * We know a device's inferred power state when all the resources
     * required for a given D-state are 'on'.
     */
    for (i=ACPI_STATE_D0; i<ACPI_STATE_D3; i++) {
        list = &device->power.states[i].resources;
        if (list->count < 1)
            continue;

        result = acpi_power_get_list_state(list, &list_state);
        if (result)
            return_VALUE(result);

        if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
            device->power.state = i;
            return_VALUE(0);
        }
    }

    device->power.state = ACPI_STATE_D3;

    return_VALUE(0);
}


int
acpi_power_transition (
    struct acpi_device  *device,
    int         state)
{
    int         result = 0;
    struct acpi_handle_list *cl = NULL; /* Current Resources */
    struct acpi_handle_list *tl = NULL; /* Target Resources */
    int         i = 0;

    if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
        return_VALUE(-1);

    if ((device->power.state < ACPI_STATE_D0) || (device->power.state > ACPI_STATE_D3))
        return_VALUE(-15);

    cl = &device->power.states[device->power.state].resources;
    tl = &device->power.states[state].resources;

    /* TBD: Resources must be ordered. */

    /*
     * First we reference all power resources required in the target list
     * (e.g. so the device doesn't lose power while transitioning).
     */
    for (i = 0; i < tl->count; i++) {
        result = acpi_power_on(tl->handles[i], device);
        if (result)
            goto end;
    }

    if (device->power.state == state) {
        goto end;
    }

    /*
     * Then we dereference all power resources used in the current list.
     */
    for (i = 0; i < cl->count; i++) {
        result = acpi_power_off_device(cl->handles[i], device);
        if (result)
            goto end;
    }

     end:
    if (result)
        device->power.state = ACPI_STATE_UNKNOWN;
    else {
    /* We shouldn't change the state till all above operations succeed */
        device->power.state = state;
    }

    return result;
}

/* --------------------------------------------------------------------------
                                Driver Interface
   -------------------------------------------------------------------------- */

int
acpi_power_add (
    struct acpi_device  *device)
{
    int  result = 0, state;
    ACPI_STATUS     status = AE_OK;
    struct acpi_power_resource *resource = NULL;
    union acpi_object   acpi_object;
    ACPI_BUFFER buffer = {sizeof(ACPI_OBJECT), &acpi_object};


    if (!device)
        return_VALUE(-1);

    resource = ExAllocatePoolWithTag(NonPagedPool,sizeof(struct acpi_power_resource),'IPCA');
    if (!resource)
        return_VALUE(-4);

    resource->device = device;
    //mutex_init(&resource->resource_lock);
    INIT_LIST_HEAD(&resource->reference);

    strcpy(resource->name, device->pnp.bus_id);
    strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
    strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
    device->driver_data = resource;

    /* Evalute the object to get the system level and resource order. */
    status = AcpiEvaluateObject(device->handle, NULL, NULL, &buffer);
    if (ACPI_FAILURE(status)) {
        result = -15;
        goto end;
    }
    resource->system_level = acpi_object.PowerResource.SystemLevel;
    resource->order = acpi_object.PowerResource.ResourceOrder;

    result = acpi_power_get_state(device->handle, &state);
    if (result)
        goto end;

    switch (state) {
    case ACPI_POWER_RESOURCE_STATE_ON:
        device->power.state = ACPI_STATE_D0;
        break;
    case ACPI_POWER_RESOURCE_STATE_OFF:
        device->power.state = ACPI_STATE_D3;
        break;
    default:
        device->power.state = ACPI_STATE_UNKNOWN;
        break;
    }

    
    DPRINT("%s [%s] (%s)\n", acpi_device_name(device),
        acpi_device_bid(device), state?"on":"off");

end:
    if (result)
        ExFreePool(resource);
    
    return result;
}


int
acpi_power_remove (
    struct acpi_device  *device,
    int         type)
{
    struct acpi_power_resource *resource = NULL;
    struct list_head *node, *next;

    if (!device || !acpi_driver_data(device))
        return_VALUE(-1);

    resource = acpi_driver_data(device);

    //mutex_lock(&resource->resource_lock);
    list_for_each_safe(node, next, &resource->reference) {
        struct acpi_power_reference *ref = container_of(node, struct acpi_power_reference, node);
        list_del(&ref->node);
        ExFreePool(ref);
    }
    //mutex_unlock(&resource->resource_lock);
    ExFreePool(resource);

    return_VALUE(0);
}

static int acpi_power_resume(struct acpi_device *device, int state)
{
    int result = 0;
    struct acpi_power_resource *resource = NULL;
    struct acpi_power_reference *ref;

    if (!device || !acpi_driver_data(device))
        return -1;

    resource = acpi_driver_data(device);

    result = acpi_power_get_state(device->handle, &state);
    if (result)
        return result;

    //mutex_lock(&resource->resource_lock);
    if (state == ACPI_POWER_RESOURCE_STATE_OFF &&
        !list_empty(&resource->reference)) {
        ref = container_of(resource->reference.next, struct acpi_power_reference, node);
        //mutex_unlock(&resource->resource_lock);
        result = acpi_power_on(device->handle, ref->device);
        return result;
    }

    //mutex_unlock(&resource->resource_lock);
    return 0;
}

int 
acpi_power_init (void)
{
    int         result = 0;

    DPRINT("acpi_power_init");

    INIT_LIST_HEAD(&acpi_power_resource_list);


    result = acpi_bus_register_driver(&acpi_power_driver);
    if (result < 0) {
        return_VALUE(-15);
    }

    return_VALUE(0);
}