LXR linux/include/linux/apple-gmux.h

   1/*
   2 * apple-gmux.h - microcontroller built into dual GPU MacBook Pro & Mac Pro
   3 * Copyright (C) 2015 Lukas Wunner <lukas@wunner.de>
   4 *
   5 * This program is free software; you can redistribute it and/or modify
   6 * it under the terms of the GNU General Public License (version 2) as
   7 * published by the Free Software Foundation.
   8 *
   9 * This program is distributed in the hope that it will be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18#ifndef LINUX_APPLE_GMUX_H
  19#define LINUX_APPLE_GMUX_H
  20
  21#include <linux/acpi.h>
  22
  23#define GMUX_ACPI_HID "APP000B"
  24
  25#if IS_ENABLED(CONFIG_APPLE_GMUX)
  26
  27/**
  28 * apple_gmux_present() - detect if gmux is built into the machine
  29 *
  30 * Drivers may use this to activate quirks specific to dual GPU MacBook Pros
  31 * and Mac Pros, e.g. for deferred probing, runtime pm and backlight.
  32 *
  33 * Return: %true if gmux is present and the kernel was configured
  34 * with CONFIG_APPLE_GMUX, %false otherwise.
  35 */
  36static inline bool apple_gmux_present(void)
  37{
  38        return acpi_dev_found(GMUX_ACPI_HID);
  39}
  40
  41#else  /* !CONFIG_APPLE_GMUX */
  42
  43static inline bool apple_gmux_present(void)
  44{
  45        return false;
  46}
  47
  48#endif /* !CONFIG_APPLE_GMUX */
  49
  50#endif /* LINUX_APPLE_GMUX_H */
  51