| Rafael J. Wysocki | c7f4865 | 2010-02-17 23:39:08 +0100 | [diff] [blame^] | 1 | /* |
| 2 | * PCIe Native PME support, ACPI-related part |
| 3 | * |
| 4 | * Copyright (C) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. |
| 5 | * |
| 6 | * This file is subject to the terms and conditions of the GNU General Public |
| 7 | * License V2. See the file "COPYING" in the main directory of this archive |
| 8 | * for more details. |
| 9 | */ |
| 10 | |
| 11 | #include <linux/pci.h> |
| 12 | #include <linux/kernel.h> |
| 13 | #include <linux/errno.h> |
| 14 | #include <linux/acpi.h> |
| 15 | #include <linux/pci-acpi.h> |
| 16 | #include <linux/pcieport_if.h> |
| 17 | |
| 18 | /** |
| 19 | * pcie_pme_acpi_setup - Request the ACPI BIOS to release control over PCIe PME. |
| 20 | * @srv - PCIe PME service for a root port or event collector. |
| 21 | * |
| 22 | * Invoked when the PCIe bus type loads PCIe PME service driver. To avoid |
| 23 | * conflict with the BIOS PCIe support requires the BIOS to yield PCIe PME |
| 24 | * control to the kernel. |
| 25 | */ |
| 26 | int pcie_pme_acpi_setup(struct pcie_device *srv) |
| 27 | { |
| 28 | acpi_status status = AE_NOT_FOUND; |
| 29 | struct pci_dev *port = srv->port; |
| 30 | acpi_handle handle; |
| 31 | int error = 0; |
| 32 | |
| 33 | if (acpi_pci_disabled) |
| 34 | return -ENOSYS; |
| 35 | |
| 36 | dev_info(&port->dev, "Requesting control of PCIe PME from ACPI BIOS\n"); |
| 37 | |
| 38 | handle = acpi_find_root_bridge_handle(port); |
| 39 | if (!handle) |
| 40 | return -EINVAL; |
| 41 | |
| 42 | status = acpi_pci_osc_control_set(handle, |
| 43 | OSC_PCI_EXPRESS_PME_CONTROL | |
| 44 | OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL); |
| 45 | if (ACPI_FAILURE(status)) { |
| 46 | dev_info(&port->dev, |
| 47 | "Failed to receive control of PCIe PME service: %s\n", |
| 48 | (status == AE_SUPPORT || status == AE_NOT_FOUND) ? |
| 49 | "no _OSC support" : "ACPI _OSC failed"); |
| 50 | error = -ENODEV; |
| 51 | } |
| 52 | |
| 53 | return error; |
| 54 | } |