Revert "PCI: Allow D3cold for hot-plug ports on Surface Books"

This reverts commit dcd3d37.

Commit c6e3313 ("PCI/ACPI: Whitelist hotplug ports for D3 if power
managed by ACPI") enables D3cold support for PCIe hot-plug bridges on a
more general level. Thus explicit white-listing of Surface devices
becomes redundant and we can drop it.

drivers/pci/pci.c

@@ -2827,32 +2827,6 @@ static const struct dmi_system_id bridge_d3_blacklist[] = {
 	{ }
 };
 
-static const struct dmi_system_id bridge_d3_hotplug_whitelist[] = {
-#ifdef CONFIG_X86
-	{
-		/*
-		 * Microsoft Surface Books have a hot-plug root port for the
-		 * discrete GPU (the device containing it can be detached form
-		 * the top-part, containing the cpu).
-		 *
-		 * If this discrete GPU is not transitioned into D3cold for
-		 * suspend, the device will become notably warm and also
-		 * consume a lot more power than desirable.
-		 *
-		 * We assume that since those devices have been confirmed
-		 * working with D3, future Surface devices will too. So let's
-		 * keep this match generic.
-		 */
-		.ident = "Microsoft Surface",
-		.matches = {
-			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"),
-			DMI_MATCH(DMI_PRODUCT_NAME, "Surface"),
-		},
-	},
-#endif
-	{ }
-};
-
 /**
  * pci_bridge_d3_possible - Is it possible to put the bridge into D3
  * @bridge: Bridge to check
@@ -2893,11 +2867,10 @@ bool pci_bridge_d3_possible(struct pci_dev *bridge)
 		/*
 		 * Hotplug ports handled natively by the OS were not validated
 		 * by vendors for runtime D3 at least until 2018 because there
-		 * was no OS support. Explicitly whitelist systems that have
-		 * been confirmed working.
+		 * was no OS support.
 		 */
 		if (bridge->is_hotplug_bridge)
-			return dmi_check_system(bridge_d3_hotplug_whitelist);
+			return false;
 
 		if (dmi_check_system(bridge_d3_blacklist))
 			return false;