dts/bindings/rtc/microcrystal,rv3032.yaml

# Copyright (c) 2024 Dipak Shetty
# SPDX-License-Identifier: Apache-2.0

description: Micro Crystal RV3032 RTC

compatible: "microcrystal,rv3032"

include:
  - name: rtc-device.yaml
  - name: i2c-device.yaml

properties:
  clkout-frequency:
    type: int
    description: |
      Frequency of the CLKOUT signal in Hertz (Hz).
      Supported frequencies:
      - XTAL mode: 32768, 1024, 64, 1 Hz (crystal-derived, may be affected by
        temperature compensation and aging correction)
      - HF mode: Any value from 8192 to 67108864 Hz in 8192 Hz steps
        (formula: frequency = (HFD + 1) × 8192 Hz where HFD = 0-8191)
        HF mode frequencies are not affected by compensation.

      If this property is omitted, the CLKOUT pin remains LOW (disabled).

      The driver will configure the RTC to use:
      1. Use XTAL mode for frequencies: 1, 64, 1024, 32768 Hz
      2. Use HF mode for other frequencies (must be multiples of 8192 Hz)

  backup-switch-mode:
    type: string
    required: true
    enum:
      - disabled
      - direct
      - level
    description: |
      Automatic backup switchover function selection:
        - disabled: The switchover function is disabled - only one power supply available (VDD)
        - direct: Direct Switching Mode (DSM): when VDD < VBACKUP, switchover occurs from VDD to
          VBACKUP without requiring VDD to drop below VTH:LSM (2.0 V)
        - level: Level Switching Mode (LSM): when VDD < VTH:LSM (2.0 V) AND VBACKUP > VTH:LSM,
          switchover occurs from VDD to VBACKUP

  trickle-resistor-ohms:
    type: int
    enum:
      - 600
      - 2000
      - 7000
      - 12000
    description: |
      Trickle charger series resistance (TCR).
      Ignored if 'trickle-charger-mode' is not present (TCM=00).
      Note: 600 ohms corresponds to TCR=00 (0.6kΩ) in RV3032.


  trickle-charger-mode:
    type: int
    enum: [1750, 3000, 4500]
    description: |
      Trickle Charger Mode (TCM).
        - If this property is not present, the trickle charger is disabled (TCM=00).
        - 1750: TCM=01. In DSM (backup-switch-mode="direct"), VDD is used as the source.
                In LSM (backup-switch-mode="level"), an internal ~1.75 V is used.
        - 3000: TCM=10. Internal charge-pump ~3.0 V, only valid in LSM.
        - 4500: TCM=11. Internal charge-pump ~4.5 V, only valid in LSM.
      Note: In LSM, the 1.75/3.0/4.5 V levels are only generated when VDD > VTH:LSM
      (typ. 2.0 V, max 2.2 V).

  int-gpios:
    type: phandle-array
    description: |
      GPIO connected to the RV3032 INT interrupt output. This signal is open-drain, active low.