1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * apple-gmux.h - microcontroller built into dual GPU MacBook Pro & Mac Pro 4 * Copyright (C) 2015 Lukas Wunner <lukas@wunner.de> 5 */ 6 7 #ifndef LINUX_APPLE_GMUX_H 8 #define LINUX_APPLE_GMUX_H 9 10 #include <linux/acpi.h> 11 12 #define GMUX_ACPI_HID "APP000B" 13 14 #if IS_ENABLED(CONFIG_APPLE_GMUX) 15 16 /** 17 * apple_gmux_present() - detect if gmux is built into the machine 18 * 19 * Drivers may use this to activate quirks specific to dual GPU MacBook Pros 20 * and Mac Pros, e.g. for deferred probing, runtime pm and backlight. 21 * 22 * Return: %true if gmux is present and the kernel was configured 23 * with CONFIG_APPLE_GMUX, %false otherwise. 24 */ 25 static inline bool apple_gmux_present(void) 26 { 27 return acpi_dev_found(GMUX_ACPI_HID); 28 } 29 30 #else /* !CONFIG_APPLE_GMUX */ 31 32 static inline bool apple_gmux_present(void) 33 { 34 return false; 35 } 36 37 #endif /* !CONFIG_APPLE_GMUX */ 38 39 #endif /* LINUX_APPLE_GMUX_H */ 40