[PATCH 1/3] PCI Hotplug: workaround for Thunderbolt on Acer Aspire S5

["Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>]

From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>

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@linux.intel.com>
---
 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.
+	 */
+	status = acpi_evaluate_integer(handle, "HRDN.EPUP._RMV", NULL,
+			&removable);
+	if (ACPI_SUCCESS(status) && removable)
+		return 1;
+
 	return 0;
 }
 
-- 
1.7.10.4