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linux/drivers/acpi/pci_bind.c
Rafael J. Wysocki b67ea76172 PCI / ACPI / PM: Platform support for PCI PME wake-up
Although the majority of PCI devices can generate PMEs that in
principle may be used to wake up devices suspended at run time,
platform support is generally necessary to convert PMEs into wake-up
events that can be delivered to the kernel.  If ACPI is used for this
purpose, PME signals generated by a PCI device will trigger the ACPI
GPE associated with the device to generate an ACPI wake-up event that
we can set up a handler for, provided that everything is configured
correctly.

Unfortunately, the subset of PCI devices that have GPEs associated
with them is quite limited.  The devices without dedicated GPEs have
to rely on the GPEs associated with other devices (in the majority of
cases their upstream bridges and, possibly, the root bridge) to
generate ACPI wake-up events in response to PME signals from them.

Add ACPI platform support for PCI PME wake-up:
o Add a framework making is possible to use ACPI system notify
  handlers for run-time PM.
o Add new PCI platform callback ->run_wake() to struct
  pci_platform_pm_ops allowing us to enable/disable the platform to
  generate wake-up events for given device.  Implemet this callback
  for the ACPI platform.
o Define ACPI wake-up handlers for PCI devices and PCI root buses and
  make the PCI-ACPI binding code register wake-up notifiers for all
  PCI devices present in the ACPI tables.
o Add function pci_dev_run_wake() which can be used by PCI drivers to
  check if given device is capable of generating wake-up events at
  run time.

Developed in cooperation with Matthew Garrett <mjg@redhat.com>.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-02-22 16:21:02 -08:00

121 lines
3.1 KiB
C

/*
* pci_bind.c - ACPI PCI Device Binding ($Revision: 2 $)
*
* 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.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/pci-acpi.h>
#include <linux/acpi.h>
#include <linux/pm_runtime.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
#define _COMPONENT ACPI_PCI_COMPONENT
ACPI_MODULE_NAME("pci_bind");
static int acpi_pci_unbind(struct acpi_device *device)
{
struct pci_dev *dev;
dev = acpi_get_pci_dev(device->handle);
if (!dev)
goto out;
device_set_run_wake(&dev->dev, false);
pci_acpi_remove_pm_notifier(device);
if (!dev->subordinate)
goto out;
acpi_pci_irq_del_prt(dev->subordinate);
device->ops.bind = NULL;
device->ops.unbind = NULL;
out:
pci_dev_put(dev);
return 0;
}
static int acpi_pci_bind(struct acpi_device *device)
{
acpi_status status;
acpi_handle handle;
struct pci_bus *bus;
struct pci_dev *dev;
dev = acpi_get_pci_dev(device->handle);
if (!dev)
return 0;
pci_acpi_add_pm_notifier(device, dev);
if (device->wakeup.flags.run_wake)
device_set_run_wake(&dev->dev, true);
/*
* Install the 'bind' function to facilitate callbacks for
* children of the P2P bridge.
*/
if (dev->subordinate) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Device %04x:%02x:%02x.%d is a PCI bridge\n",
pci_domain_nr(dev->bus), dev->bus->number,
PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn)));
device->ops.bind = acpi_pci_bind;
device->ops.unbind = acpi_pci_unbind;
}
/*
* Evaluate and parse _PRT, if exists. This code allows parsing of
* _PRT objects within the scope of non-bridge devices. Note that
* _PRTs within the scope of a PCI bridge assume the bridge's
* subordinate bus number.
*
* TBD: Can _PRTs exist within the scope of non-bridge PCI devices?
*/
status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
if (ACPI_FAILURE(status))
goto out;
if (dev->subordinate)
bus = dev->subordinate;
else
bus = dev->bus;
acpi_pci_irq_add_prt(device->handle, bus);
out:
pci_dev_put(dev);
return 0;
}
int acpi_pci_bind_root(struct acpi_device *device)
{
device->ops.bind = acpi_pci_bind;
device->ops.unbind = acpi_pci_unbind;
return 0;
}