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/*
 * Copyright (C) 2017 The Android Open Source Project
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#ifndef __ANDROID_AB_H
#define __ANDROID_AB_H

#include <common.h>

/* Android standard boot slot names are 'a', 'b', 'c', ... */
#define ANDROID_BOOT_SLOT_NAME(slot_num) ('a' + (slot_num))

/* Number of slots */
#define ANDROID_NUM_SLOTS 2

/** android_ab_select - Select the slot where to boot from.
 * On Android devices with more than one boot slot (multiple copies of the
 * kernel and system images) selects which slot should be used to boot from and
 * registers the boot attempt. This is used in by the new A/B update model where
 * one slot is updated in the background while running from the other slot. If
 * the selected slot did not successfully boot in the past, a boot attempt is
 * registered before returning from this function so it isn't selected
 * indefinitely.
 *
 * @dev_desc:		Place to store the device description pointer.
 * @part_info:		Place to store the partition information.
 * @return the slot number (0-based) on success, or -1 on error.
 */
int android_ab_select(struct blk_desc *dev_desc, disk_partition_t *part_info);

#endif