ACPI / x86: Add not-present quirk for the PCI0.SDHB.BRC1 device on the GPD win

The GPD win and its sibling the GPD pocket (99% the same electronics in a
different case) use a PCI wifi card. But the ACPI tables on both variants
contain a bug where the SDIO MMC controller for SDIO wifi cards is enabled
despite this. This SDIO MMC controller has a PCI0.SDHB.BRC1 child-device
which _PS3 method sets a GPIO causing the PCI wifi card to turn off.

At the moment there is a pretty ugly kludge in the sdhci-acpi.c code,
just to work around the bug in the DSDT of this single design. This can
be solved cleaner/simply with a quirk overriding the _STA return of the
broken PCI0.SDHB.BRC1 PCI0.SDHB.BRC1 child with a status value of 0,
so that its power_manageable flag gets cleared, avoiding this problem.

Note that even though it is not used, the _STA method for the MMC
controller is deliberately not overridden. If the status of the MMC
controller were forced to 0 it would never get suspended, which would
cause these mini-laptops to not reach S0i3 level when suspended.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/x86/utils.c b/drivers/acpi/x86/utils.c
index 190bfc2..b3fb428 100644 (file)
--- a/drivers/acpi/x86/utils.c
+++ b/drivers/acpi/x86/utils.c
@@ -94,9 +94,10 @@ static const struct override_status_id override_status_ids[] = {
        /*
         * The GPD win BIOS dated 20170221 has disabled the accelerometer, the
         * drivers sometimes cause crashes under Windows and this is how the
-        * manufacturer has solved this :| Note that the the DMI data is less
-        * generic then it seems, a board_vendor of "AMI Corporation" is quite
-        * rare and a board_name of "Default String" also is rare.
+        * manufacturer has solved this :|  The DMI match may not seem unique,
+        * but it is. In the 67000+ DMI decode dumps from linux-hardware.org
+        * only 116 have board_vendor set to "AMI Corporation" and of those 116
+        * only the GPD win and pocket entries' board_name is "Default string".
         *
         * Unfortunately the GPD pocket also uses these strings and its BIOS
         * was copy-pasted from the GPD win, so it has a disabled KIOX000A
@@ -120,6 +121,19 @@ static const struct override_status_id override_status_ids[] = {
                DMI_MATCH(DMI_PRODUCT_NAME, "Default string"),
                DMI_MATCH(DMI_BIOS_DATE, "05/25/2017")
              }),
+
+       /*
+        * The GPD win/pocket have a PCI wifi card, but its DSDT has the SDIO
+        * mmc controller enabled and that has a child-device which _PS3
+        * method sets a GPIO causing the PCI wifi card to turn off.
+        * See above remark about uniqueness of the DMI match.
+        */
+       NOT_PRESENT_ENTRY_PATH("\\_SB_.PCI0.SDHB.BRC1", ATOM_AIRMONT, {
+               DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "AMI Corporation"),
+               DMI_EXACT_MATCH(DMI_BOARD_NAME, "Default string"),
+               DMI_EXACT_MATCH(DMI_BOARD_SERIAL, "Default string"),
+               DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Default string"),
+             }),
 };
 
 bool acpi_device_override_status(struct acpi_device *adev, unsigned long long *status)