include/linux/apple-gmux.h

   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 */