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

/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * apple-gmux.h - microcontroller built into dual GPU MacBook Pro & Mac Pro
 * Copyright (C) 2015 Lukas Wunner <lukas@wunner.de>
 */

#ifndef LINUX_APPLE_GMUX_H
#define LINUX_APPLE_GMUX_H

#include <linux/acpi.h>

#define GMUX_ACPI_HID "APP000B"

#if IS_ENABLED(CONFIG_APPLE_GMUX)

/**
 * apple_gmux_present() - detect if gmux is built into the machine
 *
 * Drivers may use this to activate quirks specific to dual GPU MacBook Pros
 * and Mac Pros, e.g. for deferred probing, runtime pm and backlight.
 *
 * Return: %true if gmux is present and the kernel was configured
 * with CONFIG_APPLE_GMUX, %false otherwise.
 */
static inline bool apple_gmux_present(void)
{
	return acpi_dev_found(GMUX_ACPI_HID);
}

#else  /* !CONFIG_APPLE_GMUX */

static inline bool apple_gmux_present(void)
{
	return false;
}

#endif /* !CONFIG_APPLE_GMUX */

#endif /* LINUX_APPLE_GMUX_H */