/* SPDX-License-Identifier: BSD-2-Clause */
  /*
   * Copyright (C) 2017 The Android Open Source Project
   */
  
  #ifndef __ANDROID_AB_H
  #define __ANDROID_AB_H
  
  #include <common.h>
  
  /* Android standard boot slot names are 'a', 'b', 'c', ... */
  #define BOOT_SLOT_NAME(slot_num) ('a' + (slot_num))
  
  /* Number of slots */
  #define NUM_SLOTS 2
  
  /**
   * 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.
   *
   * @param[in] dev_desc Place to store the device description pointer
   * @param[in] part_info Place to store the partition information
   * @return The slot number (>= 0) on success, or a negative on error
   */
  int ab_select_slot(struct blk_desc *dev_desc, disk_partition_t *part_info);
  
  #endif /* __ANDROID_AB_H */