/*
    ChibiOS - Copyright (C) 2006..2018 Giovanni Di Sirio

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

        http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
*/

/**
 * @defgroup HAL_SERIAL_NOR Serial NOR Flash Driver
 * @brief   Serial NOR Flash driver.
 * @details This module implements a generic driver for serial NOR Flash
 *          devices.
 *
 * @section snorflash_1 Driver State Machine
 * The flash driver implements a state machine internally, not all the driver
 * functionalities can be used in any moment, any transition not explicitly
 * shown in the following diagram has to be considered an error and shall
 * be captured by an assertion (if enabled).
 * @dot
  digraph example {
    rankdir="LR";
    node [shape=circle, fontname=Helvetica, fontsize=8, fixedsize="true", width="0.9", height="0.9"];
    edge [fontname=Helvetica, fontsize=8];
    stop  [label="FLS_STOP\nLow Power"];
    uninit [label="FLS_UNINIT", style="bold"];
    ready [label="FLS_READY\nClock Enabled"];
    read [label="FLS_READ\nReading"];
    pgm [label="FLS_PGM\nProgramming"];
    erase [label="FLS_ERASE\nErasing"];
    uninit -> stop [label=" snorInit()", constraint=false];
    stop -> stop [label=" snorStop()"];
    stop -> ready [label=" snorStart()"];
    ready -> stop [label=" snorStop()"];
    ready -> read [label=" flashRead()\nflashVerifyErase()"];
    read -> ready [label=" return"];
    ready -> pgm [label=" flashProgram()"];
    pgm -> ready [label=" return"];
    ready -> erase [label=" \n\nflashEraseAll()\nflashEraseSector()"];
    erase -> ready [label=" flashQueryErase()\nFLASH_NO_ERROR\nFLASH_ERROR_*"];
    erase -> erase [label=" flashQueryErase()\nflashProgram()\nflashRead()\nFLASH_BUSY_ERASING"];
  }
 * @enddot
 *
 * @ingroup HAL_COMPLEX_DRIVERS
 */