Re: [PATCH v2 6/8] PCI: acpiphp: workaround for Thunderbolt on AcerAspire S5

From: Bjorn Helgaas
Date: Wed Jul 03 2013 - 17:46:19 EST


On Wed, Jul 3, 2013 at 8:04 AM, Mika Westerberg
<mika.westerberg@xxxxxxxxxxxxxxx> wrote:
> From: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
>
> Correct ACPI PCI hotplug imeplementation should have _RMV method in a
> PCI slot (device under pci bridge). In Acer Aspire S5 case we have it
> deeper in hierarchy:
>
> Device (RP05)
> {
> // ...
> Device (HRUP)
> {
> // ...
> Device (HRDN)
> {
> // ...
> Device (EPUP)
> {
> // ...
> Method (_RMV, 0, NotSerialized) // _RMV: Removal Status
> {
> Return (One)
> }
> }
> }
> }
> }
>
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
> Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> ---
> drivers/pci/hotplug/acpi_pcihp.c | 13 +++++++++++++
> 1 file changed, 13 insertions(+)
>
> diff --git a/drivers/pci/hotplug/acpi_pcihp.c b/drivers/pci/hotplug/acpi_pcihp.c
> index 2a47e82..d92ebfb 100644
> --- a/drivers/pci/hotplug/acpi_pcihp.c
> +++ b/drivers/pci/hotplug/acpi_pcihp.c
> @@ -422,6 +422,19 @@ static int pcihp_is_ejectable(acpi_handle handle)
> status = acpi_evaluate_integer(handle, "_RMV", NULL, &removable);
> if (ACPI_SUCCESS(status) && removable)
> return 1;
> +
> + /*
> + * Workaround for Thunderbolt implementation on Acer Aspire S5.
> + *
> + * Correct ACPI PCI hotplug imeplementation has _RMV method in a PCI
> + * slot (device under pci bridge). In Acer Aspire S5 case we have it
> + * deeper in hierarchy.

s/imeplementation/implementation/

If you're casting aspersions on Acer for having an incorrect ACPI
implementation, you should probably provide a spec reference. I think
it's likely that the Acer implementation is actually correct per the
spec, but Linux just isn't smart enough to handle it.

> + */
> + status = acpi_evaluate_integer(handle, "HRDN.EPUP._RMV", NULL,
> + &removable);
> + if (ACPI_SUCCESS(status) && removable)
> + return 1;
> +
> return 0;
> }
>
> --
> 1.8.3.2
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/