ACPI_STATUS AcpiInstallInterface ( ACPI_STRING InterfaceName) { ACPI_STATUS Status; ACPI_INTERFACE_INFO *InterfaceInfo; /* Parameter validation */ if (!InterfaceName || (strlen (InterfaceName) == 0)) { return (AE_BAD_PARAMETER); } Status = AcpiOsAcquireMutex (AcpiGbl_OsiMutex, ACPI_WAIT_FOREVER); if (ACPI_FAILURE (Status)) { return (Status); } /* Check if the interface name is already in the global list */ InterfaceInfo = AcpiUtGetInterface (InterfaceName); if (InterfaceInfo) { /* * The interface already exists in the list. This is OK if the * interface has been marked invalid -- just clear the bit. */ if (InterfaceInfo->Flags & ACPI_OSI_INVALID) { InterfaceInfo->Flags &= ~ACPI_OSI_INVALID; Status = AE_OK; } else { Status = AE_ALREADY_EXISTS; } } else { /* New interface name, install into the global list */ Status = AcpiUtInstallInterface (InterfaceName); } AcpiOsReleaseMutex (AcpiGbl_OsiMutex); return (Status); }
ACPI_STATUS AcpiUtOsiImplementation ( ACPI_WALK_STATE *WalkState) { ACPI_OPERAND_OBJECT *StringDesc; ACPI_OPERAND_OBJECT *ReturnDesc; ACPI_INTERFACE_INFO *InterfaceInfo; ACPI_INTERFACE_HANDLER InterfaceHandler; ACPI_STATUS Status; UINT32 ReturnValue; ACPI_FUNCTION_TRACE (UtOsiImplementation); /* Validate the string input argument (from the AML caller) */ StringDesc = WalkState->Arguments[0].Object; if (!StringDesc || (StringDesc->Common.Type != ACPI_TYPE_STRING)) { return_ACPI_STATUS (AE_TYPE); } /* Create a return object */ ReturnDesc = AcpiUtCreateInternalObject (ACPI_TYPE_INTEGER); if (!ReturnDesc) { return_ACPI_STATUS (AE_NO_MEMORY); } /* Default return value is 0, NOT SUPPORTED */ ReturnValue = 0; Status = AcpiOsAcquireMutex (AcpiGbl_OsiMutex, ACPI_WAIT_FOREVER); if (ACPI_FAILURE (Status)) { AcpiUtRemoveReference (ReturnDesc); return_ACPI_STATUS (Status); } /* Lookup the interface in the global _OSI list */ InterfaceInfo = AcpiUtGetInterface (StringDesc->String.Pointer); if (InterfaceInfo && !(InterfaceInfo->Flags & ACPI_OSI_INVALID)) { /* * The interface is supported. * Update the OsiData if necessary. We keep track of the latest * version of Windows that has been requested by the BIOS. */ if (InterfaceInfo->Value > AcpiGbl_OsiData) { AcpiGbl_OsiData = InterfaceInfo->Value; } ReturnValue = ACPI_UINT32_MAX; } AcpiOsReleaseMutex (AcpiGbl_OsiMutex); /* * Invoke an optional _OSI interface handler. The host OS may wish * to do some interface-specific handling. For example, warn about * certain interfaces or override the true/false support value. */ InterfaceHandler = AcpiGbl_InterfaceHandler; if (InterfaceHandler) { ReturnValue = InterfaceHandler ( StringDesc->String.Pointer, ReturnValue); } ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INFO, "ACPI: BIOS _OSI(\"%s\") is %ssupported\n", StringDesc->String.Pointer, ReturnValue == 0 ? "not " : "")); /* Complete the return object */ ReturnDesc->Integer.Value = ReturnValue; WalkState->ReturnDesc = ReturnDesc; return_ACPI_STATUS (AE_OK); }