[PATCH v2.1 6/8] PCI: acpiphp: workaround for Thunderbolt on Acer Aspire S5

[Mika Westerberg <mika.westerberg@linux.intel.com>]

The acpiphp driver finds out whether the device is removable by checking
whether it has _RMV method directly behind it (and if it returns 1).
However, at least on Acer Aspire S5 with Thunderbolt host router has this
method placed behind a device called EPUP (endpoint upstream port?) and not
in the usual place expected by the acpiphp driver. The ASL code below shows
how this is done on that machine:

Device (RP05)
{
	...
	Device (HRUP)
	{
		Name (_ADR, Zero)
		Name (_PRW, Package (0x02)
		{
			0x09,
			0x04
		})
		Device (HRDN)
		{
			Name (_ADR, 0x00040000)
			Name (_PRW, Package (0x02)
			{
				0x09,
				0x04
			})
			Device (EPUP)
			{
				Name (_ADR, Zero)
				Method (_RMV, 0, NotSerialized)
				{
					Return (One)
				}
			}
		}
	}
	...

Fix this by adding a DMI quirk for the Acer Aspire S5 machine that gives an
alternative path to the _RMV method.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
---
 drivers/pci/hotplug/acpi_pcihp.c | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/drivers/pci/hotplug/acpi_pcihp.c b/drivers/pci/hotplug/acpi_pcihp.c
index 2a47e82..eae1511 100644
--- a/drivers/pci/hotplug/acpi_pcihp.c
+++ b/drivers/pci/hotplug/acpi_pcihp.c
@@ -33,6 +33,7 @@
 #include <linux/acpi.h>
 #include <linux/pci-acpi.h>
 #include <linux/slab.h>
+#include <linux/dmi.h>
 
 #define MY_NAME	"acpi_pcihp"
 
@@ -408,11 +409,31 @@ got_one:
 }
 EXPORT_SYMBOL(acpi_get_hp_hw_control_from_firmware);
 
+static const struct dmi_system_id pcihp_platform_quirks[] = {
+	{
+		/*
+		 * On Acer Aspire S5 the _RMV method for the
+		 * Thunderbolt host router upstream port is not
+		 * located directly under the device but it is
+		 * instead placed a bit deeper in the hierarchy.
+		 */
+		.ident = "Acer Aspire S5",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Aspire S5-391"),
+		},
+		.driver_data = "HRDN.EPUP._RMV",
+	},
+	{ }
+};
+
 static int pcihp_is_ejectable(acpi_handle handle)
 {
 	acpi_status status;
 	acpi_handle tmp;
 	unsigned long long removable;
+	const struct dmi_system_id *id;
+
 	status = acpi_get_handle(handle, "_ADR", &tmp);
 	if (ACPI_FAILURE(status))
 		return 0;
@@ -422,6 +443,19 @@ static int pcihp_is_ejectable(acpi_handle handle)
 	status = acpi_evaluate_integer(handle, "_RMV", NULL, &removable);
 	if (ACPI_SUCCESS(status) && removable)
 		return 1;
+
+	/*
+	 * Try to look if there is a platform specific method that we can
+	 * use to determine if the device is removable or not.
+	 */
+	id = dmi_first_match(pcihp_platform_quirks);
+	if (id && id->driver_data) {
+		status = acpi_evaluate_integer(handle, id->driver_data, NULL,
+					       &removable);
+		if (ACPI_SUCCESS(status) && removable)
+			return 1;
+	}
+
 	return 0;
 }
 
-- 
1.8.3.2