/*
    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
                 2011 Giovanni Di Sirio.

    This file is part of ChibiOS/RT.

    ChibiOS/RT is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    ChibiOS/RT is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

/**
 * @defgroup SDC SDC Driver
 * @brief   Generic SD Card Driver.
 * @details This module implements a generic SDC (Secure Digital Card) driver.
 * @pre     In order to use the SDC driver the @p HAL_USE_SDC option
 *          must be enabled in @p halconf.h.
 *
 * @section sdc_1 Driver State Machine
 * The 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).
 * @if LATEX_PDF
 * @dot
  digraph example {
    size="5, 7";
    rankdir="LR";

    node [shape=circle, fontname=Sans, fontsize=8, fixedsize="true", width="0.9", height="0.9"];
    edge [fontname=Sans, fontsize=8];

    stop  [label="SDC_STOP\nLow Power"];
    uninit [label="SDC_UNINIT", style="bold"];
    ready [label="SDC_READY\nClock Enabled"];
    connecting [label="SDC_CONN.ING\nConnecting"];
    disconnecting [label="SDC_DISC.ING\nDisconnecting"];
    active [label="SDC_ACTIVE\nCard Ready"];
    reading [label="SDC_READING\nReading"];
    writing [label="SDC_WRITING\nWriting"];

    uninit -> stop [label=" sdcInit()", constraint=false];
    stop -> stop [label="\nsdcStop()"];
    stop -> ready [label="\nsdcStart()"];
    ready -> stop [label="\nsdcStop()"];
    ready -> ready [label="\nsdcStart()\nsdcDisconnect()"];
    ready -> connecting [label="\nsdcConnect()"];
    connecting -> active [label="\nconnection\nsuccessful"];
    connecting -> active [label="\nsdcConnect()", dir="back"];
    connecting -> ready [label="\nconnection\nfailed"];
    disconnecting -> active [label="\nsdcDisconnect()", dir="back"];
    ready -> disconnecting [label="\ndisconnection\nfinished", dir="back"];
    active -> reading [label="\nsdcRead()"];
    reading -> active [label="\nread finished\nread error"];
    active -> writing [label="\nsdcWrite()"];
    writing -> active [label="\nwrite finished\nwrite error"];
  }
 * @enddot
 * @else
 * @dot
  digraph example {
    rankdir="LR";

    node [shape=circle, fontname=Sans, fontsize=8, fixedsize="true", width="0.9", height="0.9"];
    edge [fontname=Sans, fontsize=8];

    stop  [label="SDC_STOP\nLow Power"];
    uninit [label="SDC_UNINIT", style="bold"];
    ready [label="SDC_READY\nClock Enabled"];
    connecting [label="SDC_CONN.ING\nConnecting"];
    disconnecting [label="SDC_DISC.ING\nDisconnecting"];
    active [label="SDC_ACTIVE\nCard Ready"];
    reading [label="SDC_READING\nReading"];
    writing [label="SDC_WRITING\nWriting"];

    uninit -> stop [label=" sdcInit()", constraint=false];
    stop -> stop [label="\nsdcStop()"];
    stop -> ready [label="\nsdcStart()"];
    ready -> stop [label="\nsdcStop()"];
    ready -> ready [label="\nsdcStart()\nsdcDisconnect()"];
    ready -> connecting [label="\nsdcConnect()"];
    connecting -> active [label="\nconnection\nsuccessful"];
    connecting -> active [label="\nsdcConnect()", dir="back"];
    connecting -> ready [label="\nconnection\nfailed"];
    disconnecting -> active [label="\nsdcDisconnect()", dir="back"];
    ready -> disconnecting [label="\ndisconnection\nfinished", dir="back"];
    active -> reading [label="\nsdcRead()"];
    reading -> active [label="\nread finished\nread error"];
    active -> writing [label="\nsdcWrite()"];
    writing -> active [label="\nwrite finished\nwrite error"];
  }
 * @enddot
 * @endif
 *
 * @section sdc_2 SDC Operations.
 * This driver allows to read or write single or multiple 512 bytes blocks
 * on a SD Card.
 *
 * @ingroup IO
 */