> _OSC should be ran on a root bridge instead of the device itself.
> Do this before touching OSHP since PCI fw specs states that _OSC
> should be preferred over OSHP (however if the device has OSHP but
> not _OSC -- not a root bridge -- it's not).
>
> Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
> Cc:
kristen.c.accardi@intel.com
> Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
> ---
> drivers/pci/hotplug/acpi_pcihp.c | 41
> ++++++++++++++++++++++++++----------- 1 files changed, 29 insertions(+), 12
> deletions(-)
>
> diff --git a/drivers/pci/hotplug/acpi_pcihp.c
> b/drivers/pci/hotplug/acpi_pcihp.c index 93e37f0..bd83197 100644
> --- a/drivers/pci/hotplug/acpi_pcihp.c
> +++ b/drivers/pci/hotplug/acpi_pcihp.c
> @@ -382,7 +382,7 @@ EXPORT_SYMBOL_GPL(acpi_get_hp_params_from_firmware);
> int acpi_get_hp_hw_control_from_firmware(struct pci_dev *dev, u32 flags)
> {
> acpi_status status;
> - acpi_handle chandle, handle = DEVICE_ACPI_HANDLE(&(dev->dev));
> + acpi_handle chandle, handle;
> struct pci_dev *pdev = dev;
> struct pci_bus *parent;
> struct acpi_buffer string = { ACPI_ALLOCATE_BUFFER, NULL };
> @@ -399,10 +399,28 @@ int acpi_get_hp_hw_control_from_firmware(struct
> pci_dev *dev, u32 flags) * Per PCI firmware specification, we should run
> the ACPI _OSC
> * method to get control of hotplug hardware before using it. If
> * an _OSC is missing, we look for an OSHP to do the same thing.
> - * To handle different BIOS behavior, we look for _OSC and OSHP
> - * within the scope of the hotplug controller and its parents,
> + * To handle different BIOS behavior, we look for _OSC on a root
> + * bridge preferentially (according to PCI fw spec). Later for
> + * OSHP within the scope of the hotplug controller and its parents,
> * upto the host bridge under which this controller exists.
> */
> + while (pdev->bus->self)
> + pdev = pdev->bus->self;
> + handle = acpi_get_pci_rootbridge_handle(pci_domain_nr(pdev->bus),
> + pdev->bus->number);
> + if (handle) {
> + acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
> + dbg("Trying to get hotplug control for %s\n",
> + (char *)string.pointer);
> + status = pci_osc_control_set(handle, flags);
> + if (ACPI_SUCCESS(status))
> + goto got_one;
> + kfree(string.pointer);
> + string = (struct acpi_buffer){ ACPI_ALLOCATE_BUFFER, NULL };
> + }
> +
> + pdev = dev;
> + handle = DEVICE_ACPI_HANDLE(&dev->dev);
> while (!handle) {
> /*
> * This hotplug controller was not listed in the ACPI name
> @@ -427,15 +445,9 @@ int acpi_get_hp_hw_control_from_firmware(struct
> pci_dev *dev, u32 flags) acpi_get_name(handle, ACPI_FULL_PATHNAME,
> &string);
> dbg("Trying to get hotplug control for %s \n",
> (char *)string.pointer);
> - status = pci_osc_control_set(handle, flags);
> - if (status == AE_NOT_FOUND)
> - status = acpi_run_oshp(handle);
> - if (ACPI_SUCCESS(status)) {
> - dbg("Gained control for hotplug HW for pci %s (%s)\n",
> - pci_name(dev), (char *)string.pointer);
> - kfree(string.pointer);
> - return 0;
> - }
> + status = acpi_run_oshp(handle);
> + if (ACPI_SUCCESS(status))
> + goto got_one;
> if (acpi_root_bridge(handle))
> break;
> chandle = handle;
> @@ -449,6 +461,11 @@ int acpi_get_hp_hw_control_from_firmware(struct
> pci_dev *dev, u32 flags)
>
> kfree(string.pointer);
> return -ENODEV;
> +got_one:
> + dbg("Gained control for hotplug HW for pci %s (%s)\n", pci_name(dev),
> + (char *)string.pointer);
> + kfree(string.pointer);
> + return 0;
> }
> EXPORT_SYMBOL(acpi_get_hp_hw_control_from_firmware);
