FreeRTOS-Labs/Source/FreeRTOS-Plus-FAT/portable/ATSAM4E/ff_sddisk_r.c - third_party/github/FreeRTOS/FreeRTOS-Kernel - Git at Google

 /*
  * FreeRTOS+FAT build 191128 - Note:  FreeRTOS+FAT is still in the lab!
  * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
  * Authors include James Walmsley, Hein Tibosch and Richard Barry
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy of
  * this software and associated documentation files (the "Software"), to deal in
  * the Software without restriction, including without limitation the rights to
  * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
  * the Software, and to permit persons to whom the Software is furnished to do so,
  * subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in all
  * copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
  * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
  * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
  * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  * https://www.FreeRTOS.org
  *
  */

 /* Standard includes. */
 #include <stdlib.h>
 #include <string.h>
 #include <stdarg.h>
 #include <stdio.h>

 /* FreeRTOS includes. */
 #include "FreeRTOS.h"
 #include "task.h"
 #include "semphr.h"
 #include "portmacro.h"

 /* FreeRTOS+FAT includes. */
 #include "ff_sddisk.h"
 #include "ff_sys.h"

 /* Atmel includes. */
 #include <sd_mmc.h>

 /* Misc definitions. */
 #define sdSIGNATURE 			0x41404342UL
 #define sdHUNDRED_64_BIT		( 100ull )
 #define sdBYTES_PER_MB			( 1024ull * 1024ull )
 #define sdSECTORS_PER_MB		( sdBYTES_PER_MB / 512ull )
 #define sdIOMAN_MEM_SIZE		4096
 #define xSDCardInfo				( sd_mmc_cards[ 0 ] )

 /*-----------------------------------------------------------*/

 /*
  * Return pdFALSE if the SD card is not inserted.
  */
 static BaseType_t prvSDDetect( void );

 /*
  * Check if the card is present, and if so, print out some info on the card.
  */
 static BaseType_t prvSDMMCInit( BaseType_t xDriveNumber );

 /*-----------------------------------------------------------*/

 /*
  * Mutex for partition.
  */
 static SemaphoreHandle_t xPlusFATMutex = NULL;

 /*
  * Remembers if the card is currently considered to be present.
  */
 static BaseType_t xSDCardStatus = pdFALSE;

 /*-----------------------------------------------------------*/

 static int32_t prvFFRead( uint8_t *pucBuffer, uint32_t ulSectorNumber, uint32_t ulSectorCount, FF_Disk_t *pxDisk )
 {
 int32_t lReturnCode = FF_ERR_IOMAN_OUT_OF_BOUNDS_READ | FF_ERRFLAG, lResult;

 	if( ( pxDisk != NULL ) &&
 		( xSDCardStatus == pdPASS ) &&
 		( pxDisk->ulSignature == sdSIGNATURE ) &&
 		( pxDisk->xStatus.bIsInitialised != pdFALSE ) &&
 		( ulSectorNumber < pxDisk->ulNumberOfSectors ) &&
 		( ( pxDisk->ulNumberOfSectors - ulSectorNumber ) >= ulSectorCount ) )
 	{
 		lResult = sd_physical_read( ulSectorNumber, pucBuffer, ulSectorCount);

 		if( lResult != pdFALSE )
 		{
 			lReturnCode = 0L;
 		}
 		else
 		{
 			/* Some error occurred. */
 			FF_PRINTF( "prvFFRead: %lu: %lu\n", ulSectorNumber, lResult );
 		}
 	}
 	else
 	{
 		/* Make sure no random data is in the returned buffer. */
 		memset( ( void * ) pucBuffer, '\0', ulSectorCount * 512UL );

 		if( pxDisk->xStatus.bIsInitialised != pdFALSE )
 		{
 			FF_PRINTF( "prvFFRead: warning: %lu + %lu > %lu\n", ulSectorNumber, ulSectorCount, pxDisk->ulNumberOfSectors );
 		}
 	}

 	return lReturnCode;
 }
 /*-----------------------------------------------------------*/

 static int32_t prvFFWrite( uint8_t *pucBuffer, uint32_t ulSectorNumber, uint32_t ulSectorCount, FF_Disk_t *pxDisk )
 {
 int32_t lReturnCode = FF_ERR_IOMAN_OUT_OF_BOUNDS_READ | FF_ERRFLAG;
 BaseType_t xResult;

 	if( ( pxDisk != NULL ) &&
 		( xSDCardStatus == pdPASS ) &&
 		( pxDisk->ulSignature == sdSIGNATURE ) &&
 		( pxDisk->xStatus.bIsInitialised != pdFALSE ) &&
 		( ulSectorNumber < pxDisk->ulNumberOfSectors ) &&
 		( ( pxDisk->ulNumberOfSectors - ulSectorNumber ) >= ulSectorCount ) )
 	{
 		xResult = sd_physical_write( ulSectorNumber, pucBuffer, ulSectorCount );

 		if( xResult != pdFALSE )
 		{
 			/* No errors. */
 			lReturnCode = 0L;
 		}
 		else
 		{
 			FF_PRINTF( "prvFFWrite: %lu: %lu\n", ulSectorNumber, xResult  );
 		}
 	}
 	else
 	{
 		if( pxDisk->xStatus.bIsInitialised != pdFALSE )
 		{
 			FF_PRINTF( "prvFFWrite: warning: %lu + %lu > %lu\n", ulSectorNumber, ulSectorCount, pxDisk->ulNumberOfSectors );
 		}
 	}

 	return lReturnCode;
 }
 /*-----------------------------------------------------------*/

 void FF_SDDiskFlush( FF_Disk_t *pxDisk )
 {
 	if( ( pxDisk != NULL ) &&
 		( pxDisk->xStatus.bIsInitialised != pdFALSE ) &&
 		( pxDisk->pxIOManager != NULL ) )
 	{
 		FF_FlushCache( pxDisk->pxIOManager );
 	}
 }
 /*-----------------------------------------------------------*/

 /* Initialise the SDIO driver and mount an SD card */
 FF_Disk_t *FF_SDDiskInit( const char *pcName )
 {
 FF_Error_t xFFError;
 BaseType_t xPartitionNumber = 0;
 FF_CreationParameters_t xParameters;
 FF_Disk_t *pxDisk;

 	xSDCardStatus = prvSDMMCInit( 0 );

 	if( xSDCardStatus != pdPASS )
 	{
 		FF_PRINTF( "FF_SDDiskInit: prvSDMMCInit failed\n" );
 		pxDisk = NULL;
 	}
 	else
 	{
 		pxDisk = ( FF_Disk_t * )pvPortMalloc( sizeof( *pxDisk ) );
 		if( pxDisk == NULL )
 		{
 			FF_PRINTF( "FF_SDDiskInit: Malloc failed\n" );
 		}
 		else
 		{
 			/* Initialise the created disk structure. */
 			memset( pxDisk, '\0', sizeof( *pxDisk ) );

 			/* The Atmel MMC driver sets capacity as a number of KB.
 			Divide by two to get the number of 512-byte sectors. */
 			pxDisk->ulNumberOfSectors = xSDCardInfo.capacity << 1;

 			if( xPlusFATMutex == NULL )
 			{
 				xPlusFATMutex = xSemaphoreCreateRecursiveMutex();
 			}
 			pxDisk->ulSignature = sdSIGNATURE;

 			if( xPlusFATMutex != NULL)
 			{
 				memset( &xParameters, '\0', sizeof( xParameters ) );
 				xParameters.ulMemorySize = sdIOMAN_MEM_SIZE;
 				xParameters.ulSectorSize = 512;
 				xParameters.fnWriteBlocks = prvFFWrite;
 				xParameters.fnReadBlocks = prvFFRead;
 				xParameters.pxDisk = pxDisk;

 				/* prvFFRead()/prvFFWrite() are not re-entrant and must be
 				protected with the use of a semaphore. */
 				xParameters.xBlockDeviceIsReentrant = pdFALSE;

 				/* The semaphore will be used to protect critical sections in
 				the +FAT driver, and also to avoid concurrent calls to
 				prvFFRead()/prvFFWrite() from different tasks. */
 				xParameters.pvSemaphore = ( void * ) xPlusFATMutex;

 				pxDisk->pxIOManager = FF_CreateIOManger( &xParameters, &xFFError );

 				if( pxDisk->pxIOManager == NULL )
 				{
 					FF_PRINTF( "FF_SDDiskInit: FF_CreateIOManger: %s\n", (const char*)FF_GetErrMessage( xFFError ) );
 					FF_SDDiskDelete( pxDisk );
 					pxDisk = NULL;
 				}
 				else
 				{
 					pxDisk->xStatus.bIsInitialised = pdTRUE;
 					pxDisk->xStatus.bPartitionNumber = xPartitionNumber;
 					if( FF_SDDiskMount( pxDisk ) == 0 )
 					{
 						FF_SDDiskDelete( pxDisk );
 						pxDisk = NULL;
 					}
 					else
 					{
 						if( pcName == NULL )
 						{
 							pcName = "/";
 						}
 						FF_FS_Add( pcName, pxDisk );
 						FF_PRINTF( "FF_SDDiskInit: Mounted SD-card as root \"%s\"\n", pcName );
 						FF_SDDiskShowPartition( pxDisk );
 					}
 				}	/* if( pxDisk->pxIOManager != NULL ) */
 			}	/* if( xPlusFATMutex != NULL) */
 		}	/* if( pxDisk != NULL ) */
 	}	/* if( xSDCardStatus == pdPASS ) */

 	return pxDisk;
 }
 /*-----------------------------------------------------------*/

 BaseType_t FF_SDDiskFormat( FF_Disk_t *pxDisk, BaseType_t aPart )
 {
 FF_Error_t xError;
 BaseType_t xReturn = pdFAIL;

 	xError = FF_Unmount( pxDisk );

 	if( FF_isERR( xError ) != pdFALSE )
 	{
 		FF_PRINTF( "FF_SDDiskFormat: unmount fails: %08x\n", ( unsigned ) xError );
 	}
 	else
 	{
 		/* Format the drive - try FAT32 with large clusters. */
 		xError = FF_Format( pxDisk, aPart, pdFALSE, pdFALSE);

 		if( FF_isERR( xError ) )
 		{
 			FF_PRINTF( "FF_SDDiskFormat: %s\n", (const char*)FF_GetErrMessage( xError ) );
 		}
 		else
 		{
 			FF_PRINTF( "FF_SDDiskFormat: OK, now remounting\n" );
 			pxDisk->xStatus.bPartitionNumber = aPart;
 			xError = FF_SDDiskMount( pxDisk );
 			FF_PRINTF( "FF_SDDiskFormat: rc %08x\n", ( unsigned )xError );
 			if( FF_isERR( xError ) == pdFALSE )
 			{
 				xReturn = pdPASS;
 				FF_SDDiskShowPartition( pxDisk );
 			}
 		}
 	}

 	return xReturn;
 }
 /*-----------------------------------------------------------*/

 BaseType_t FF_SDDiskUnmount( FF_Disk_t *pxDisk )
 {
 FF_Error_t xFFError;
 BaseType_t xReturn = pdPASS;

 	if( ( pxDisk != NULL ) && ( pxDisk->xStatus.bIsMounted != pdFALSE ) )
 	{
 		pxDisk->xStatus.bIsMounted = pdFALSE;
 		xFFError = FF_Unmount( pxDisk );

 		if( FF_isERR( xFFError ) )
 		{
 			FF_PRINTF( "FF_SDDiskUnmount: rc %08x\n", ( unsigned )xFFError );
 			xReturn = pdFAIL;
 		}
 		else
 		{
 			FF_PRINTF( "Drive unmounted\n" );
 		}
 	}

 	return xReturn;
 }
 /*-----------------------------------------------------------*/

 BaseType_t FF_SDDiskReinit( FF_Disk_t *pxDisk )
 {
 BaseType_t xStatus = prvSDMMCInit( 0 ); /* Hard coded index. */

 	/*_RB_ parameter not used. */
 	( void ) pxDisk;

 	FF_PRINTF( "FF_SDDiskReinit: rc %08x\n", ( unsigned ) xStatus );
 	return xStatus;
 }
 /*-----------------------------------------------------------*/

 BaseType_t FF_SDDiskMount( FF_Disk_t *pxDisk )
 {
 FF_Error_t xFFError;
 BaseType_t xReturn;

 	/* Mount the partition */
 	xFFError = FF_Mount( pxDisk, pxDisk->xStatus.bPartitionNumber );

 	if( FF_isERR( xFFError ) )
 	{
 		FF_PRINTF( "FF_SDDiskMount: %08lX\n", xFFError );
 		xReturn = pdFAIL;
 	}
 	else
 	{
 		pxDisk->xStatus.bIsMounted = pdTRUE;
 		FF_PRINTF( "****** FreeRTOS+FAT initialized %lu sectors\n", pxDisk->pxIOManager->xPartition.ulTotalSectors );
 		xReturn = pdPASS;
 	}

 	return xReturn;
 }
 /*-----------------------------------------------------------*/

 FF_IOManager_t *sddisk_ioman( FF_Disk_t *pxDisk )
 {
 FF_IOManager_t *pxReturn;

 	if( ( pxDisk != NULL ) && ( pxDisk->xStatus.bIsInitialised != pdFALSE ) )
 	{
 		pxReturn = pxDisk->pxIOManager;
 	}
 	else
 	{
 		pxReturn = NULL;
 	}
 	return pxReturn;
 }
 /*-----------------------------------------------------------*/

 /* Release all resources */
 BaseType_t FF_SDDiskDelete( FF_Disk_t *pxDisk )
 {
 	if( pxDisk != NULL )
 	{
 		pxDisk->ulSignature = 0;
 		pxDisk->xStatus.bIsInitialised = 0;
 		if( pxDisk->pxIOManager != NULL )
 		{
 			if( FF_Mounted( pxDisk->pxIOManager ) != pdFALSE )
 			{
 				FF_Unmount( pxDisk );
 			}
 			FF_DeleteIOManager( pxDisk->pxIOManager );
 		}

 		vPortFree( pxDisk );
 	}
 	return 1;
 }
 /*-----------------------------------------------------------*/

 BaseType_t FF_SDDiskShowPartition( FF_Disk_t *pxDisk )
 {
 FF_Error_t xError;
 uint64_t ullFreeSectors;
 uint32_t ulTotalSizeMB, ulFreeSizeMB;
 int iPercentageFree;
 FF_IOManager_t *pxIOManager;
 const char *pcTypeName = "unknown type";
 BaseType_t xReturn = pdPASS;

 	if( pxDisk == NULL )
 	{
 		xReturn = pdFAIL;
 	}
 	else
 	{
 		pxIOManager = pxDisk->pxIOManager;

 		FF_PRINTF( "Reading FAT and calculating Free Space\n" );

 		switch( pxIOManager->xPartition.ucType )
 		{
 			case FF_T_FAT12:
 				pcTypeName = "FAT12";
 				break;

 			case FF_T_FAT16:
 				pcTypeName = "FAT16";
 				break;

 			case FF_T_FAT32:
 				pcTypeName = "FAT32";
 				break;

 			default:
 				pcTypeName = "UNKOWN";
 				break;
 		}

 		FF_GetFreeSize( pxIOManager, &xError );

 		ullFreeSectors = pxIOManager->xPartition.ulFreeClusterCount * pxIOManager->xPartition.ulSectorsPerCluster;
 		iPercentageFree = ( int ) ( ( sdHUNDRED_64_BIT * ullFreeSectors + pxIOManager->xPartition.ulDataSectors / 2 ) /
 			( ( uint64_t )pxIOManager->xPartition.ulDataSectors ) );

 		ulTotalSizeMB = pxIOManager->xPartition.ulDataSectors / sdSECTORS_PER_MB;
 		ulFreeSizeMB = ( uint32_t ) ( ullFreeSectors / sdSECTORS_PER_MB );

 		/* It is better not to use the 64-bit format such as %Lu because it
 		might not be implemented. */
 		FF_PRINTF( "Partition Nr   %8u\n", pxDisk->xStatus.bPartitionNumber );
 		FF_PRINTF( "Type           %8u (%s)\n", pxIOManager->xPartition.ucType, pcTypeName );
 		FF_PRINTF( "VolLabel       '%8s' \n", pxIOManager->xPartition.pcVolumeLabel );
 		FF_PRINTF( "TotalSectors   %8lu\n", pxIOManager->xPartition.ulTotalSectors );
 		FF_PRINTF( "SecsPerCluster %8lu\n", pxIOManager->xPartition.ulSectorsPerCluster );
 		FF_PRINTF( "Size           %8lu MB\n", ulTotalSizeMB );
 		FF_PRINTF( "FreeSize       %8lu MB ( %d perc free )\n", ulFreeSizeMB, iPercentageFree );
 	}

 	return xReturn;
 }
 /*-----------------------------------------------------------*/

 BaseType_t FF_SDDiskDetect( FF_Disk_t *pxDisk )
 {
 BaseType_t xIsPresent;
 void *pvSemaphore;

 	if( ( pxDisk != NULL ) &&
 		( pxDisk->pxIOManager ) )
 	{
 		pvSemaphore = pxDisk->pxIOManager->pvSemaphore;
 	}
 	else
 	{
 		pvSemaphore = NULL;
 	}

 	/*_RB_ Can these NULL checks be moved inside the FF_nnnSemaphore() functions? */
 	/*_HT_ I'm afraid not, both functions start with configASSERT( pxSemaphore ); */
 	if( pvSemaphore != NULL )
 	{
 		FF_PendSemaphore( pvSemaphore );
 	}

 	xIsPresent = prvSDDetect();

 	if( pvSemaphore != NULL )
 	{
 		FF_ReleaseSemaphore( pvSemaphore );
 	}

 	return xIsPresent;
 }
 /*-----------------------------------------------------------*/

 static BaseType_t prvSDDetect( void )
 {
 static BaseType_t xWasPresent;
 BaseType_t xIsPresent;
 sd_mmc_err_t xSDPresence;

 	if( xWasPresent == pdFALSE )
 	{
 		/* Try to initialize SD MMC stack */
 		sd_mmc_init();
 		xSDPresence = sd_mmc_check( 0 );
 		if( ( xSDPresence == SD_MMC_OK ) || ( xSDPresence == SD_MMC_INIT_ONGOING ) )
 		{
 			xIsPresent = pdTRUE;
 		}
 		else
 		{
 			xIsPresent = pdFALSE;
 		}
 	}
 	else
 	{
 		/* See if the card is still present. */
 		xSDPresence = sd_mmc_check_status(0);
 		if( xSDPresence == SD_MMC_OK )
 		{
 			xIsPresent = pdTRUE;
 		}
 		else
 		{
 			xIsPresent = pdFALSE;
 		}
 	}
 	xWasPresent = xIsPresent;

 	return xIsPresent;
 }
 /*-----------------------------------------------------------*/

 static BaseType_t prvSDMMCInit( BaseType_t xDriveNumber )
 {
 BaseType_t xReturn;

 	/* 'xDriveNumber' not yet in use. */
 	( void ) xDriveNumber;

 	/* Check if the SD card is plugged in the slot */
 	if( prvSDDetect() == pdFALSE )
 	{
 		FF_PRINTF( "No SD card detected\n" );
 		xReturn = pdFAIL;
 	}
 	else
 	{
 		FF_PRINTF( "HAL_SD_Init: type: %s Capacity: %lu MB\n",
 			xSDCardInfo.type & CARD_TYPE_HC ? "SDHC" : "SD",
 			( xSDCardInfo.capacity << 1 ) / 2048 );

 		xReturn = pdPASS;
 	}

 	return xReturn;
 }
 /*-----------------------------------------------------------*/
	/*
	* FreeRTOS+FAT build 191128 - Note: FreeRTOS+FAT is still in the lab!
	* Copyright (C) 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
	* Authors include James Walmsley, Hein Tibosch and Richard Barry
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy of
	* this software and associated documentation files (the "Software"), to deal in
	* the Software without restriction, including without limitation the rights to
	* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
	* the Software, and to permit persons to whom the Software is furnished to do so,
	* subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in all
	* copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
	* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
	* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
	* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
	*
	* https://www.FreeRTOS.org
	*
	*/

	/* Standard includes. */
	#include <stdlib.h>
	#include <string.h>
	#include <stdarg.h>
	#include <stdio.h>

	/* FreeRTOS includes. */
	#include "FreeRTOS.h"
	#include "task.h"
	#include "semphr.h"
	#include "portmacro.h"

	/* FreeRTOS+FAT includes. */
	#include "ff_sddisk.h"
	#include "ff_sys.h"

	/* Atmel includes. */
	#include <sd_mmc.h>

	/* Misc definitions. */
	#define sdSIGNATURE 0x41404342UL
	#define sdHUNDRED_64_BIT ( 100ull )
	#define sdBYTES_PER_MB ( 1024ull * 1024ull )
	#define sdSECTORS_PER_MB ( sdBYTES_PER_MB / 512ull )
	#define sdIOMAN_MEM_SIZE 4096
	#define xSDCardInfo ( sd_mmc_cards[ 0 ] )

	/-----------------------------------------------------------/

	/*
	* Return pdFALSE if the SD card is not inserted.
	*/
	static BaseType_t prvSDDetect( void );

	/*
	* Check if the card is present, and if so, print out some info on the card.
	*/
	static BaseType_t prvSDMMCInit( BaseType_t xDriveNumber );

	/-----------------------------------------------------------/

	/*
	* Mutex for partition.
	*/
	static SemaphoreHandle_t xPlusFATMutex = NULL;

	/*
	* Remembers if the card is currently considered to be present.
	*/
	static BaseType_t xSDCardStatus = pdFALSE;

	/-----------------------------------------------------------/

	static int32_t prvFFRead( uint8_t pucBuffer, uint32_t ulSectorNumber, uint32_t ulSectorCount, FF_Disk_t pxDisk )
	{
	int32_t lReturnCode = FF_ERR_IOMAN_OUT_OF_BOUNDS_READ \| FF_ERRFLAG, lResult;

	if( ( pxDisk != NULL ) &&
	( xSDCardStatus == pdPASS ) &&
	( pxDisk->ulSignature == sdSIGNATURE ) &&
	( pxDisk->xStatus.bIsInitialised != pdFALSE ) &&
	( ulSectorNumber < pxDisk->ulNumberOfSectors ) &&
	( ( pxDisk->ulNumberOfSectors - ulSectorNumber ) >= ulSectorCount ) )
	{
	lResult = sd_physical_read( ulSectorNumber, pucBuffer, ulSectorCount);

	if( lResult != pdFALSE )
	{
	lReturnCode = 0L;
	}
	else
	{
	/* Some error occurred. */
	FF_PRINTF( "prvFFRead: %lu: %lu\n", ulSectorNumber, lResult );
	}
	}
	else
	{
	/* Make sure no random data is in the returned buffer. */
	memset( ( void * ) pucBuffer, '\0', ulSectorCount * 512UL );

	if( pxDisk->xStatus.bIsInitialised != pdFALSE )
	{
	FF_PRINTF( "prvFFRead: warning: %lu + %lu > %lu\n", ulSectorNumber, ulSectorCount, pxDisk->ulNumberOfSectors );
	}
	}

	return lReturnCode;
	}
	/-----------------------------------------------------------/

	static int32_t prvFFWrite( uint8_t pucBuffer, uint32_t ulSectorNumber, uint32_t ulSectorCount, FF_Disk_t pxDisk )
	{
	int32_t lReturnCode = FF_ERR_IOMAN_OUT_OF_BOUNDS_READ \| FF_ERRFLAG;
	BaseType_t xResult;

	if( ( pxDisk != NULL ) &&
	( xSDCardStatus == pdPASS ) &&
	( pxDisk->ulSignature == sdSIGNATURE ) &&
	( pxDisk->xStatus.bIsInitialised != pdFALSE ) &&
	( ulSectorNumber < pxDisk->ulNumberOfSectors ) &&
	( ( pxDisk->ulNumberOfSectors - ulSectorNumber ) >= ulSectorCount ) )
	{
	xResult = sd_physical_write( ulSectorNumber, pucBuffer, ulSectorCount );

	if( xResult != pdFALSE )
	{
	/* No errors. */
	lReturnCode = 0L;
	}
	else
	{
	FF_PRINTF( "prvFFWrite: %lu: %lu\n", ulSectorNumber, xResult );
	}
	}
	else
	{
	if( pxDisk->xStatus.bIsInitialised != pdFALSE )
	{
	FF_PRINTF( "prvFFWrite: warning: %lu + %lu > %lu\n", ulSectorNumber, ulSectorCount, pxDisk->ulNumberOfSectors );
	}
	}

	return lReturnCode;
	}
	/-----------------------------------------------------------/

	void FF_SDDiskFlush( FF_Disk_t *pxDisk )
	{
	if( ( pxDisk != NULL ) &&
	( pxDisk->xStatus.bIsInitialised != pdFALSE ) &&
	( pxDisk->pxIOManager != NULL ) )
	{
	FF_FlushCache( pxDisk->pxIOManager );
	}
	}
	/-----------------------------------------------------------/

	/* Initialise the SDIO driver and mount an SD card */
	FF_Disk_t FF_SDDiskInit( const char pcName )
	{
	FF_Error_t xFFError;
	BaseType_t xPartitionNumber = 0;
	FF_CreationParameters_t xParameters;
	FF_Disk_t *pxDisk;

	xSDCardStatus = prvSDMMCInit( 0 );

	if( xSDCardStatus != pdPASS )
	{
	FF_PRINTF( "FF_SDDiskInit: prvSDMMCInit failed\n" );
	pxDisk = NULL;
	}
	else
	{
	pxDisk = ( FF_Disk_t * )pvPortMalloc( sizeof( *pxDisk ) );
	if( pxDisk == NULL )
	{
	FF_PRINTF( "FF_SDDiskInit: Malloc failed\n" );
	}
	else
	{
	/* Initialise the created disk structure. */
	memset( pxDisk, '\0', sizeof( *pxDisk ) );

	/* The Atmel MMC driver sets capacity as a number of KB.
	Divide by two to get the number of 512-byte sectors. */
	pxDisk->ulNumberOfSectors = xSDCardInfo.capacity << 1;

	if( xPlusFATMutex == NULL )
	{
	xPlusFATMutex = xSemaphoreCreateRecursiveMutex();
	}
	pxDisk->ulSignature = sdSIGNATURE;

	if( xPlusFATMutex != NULL)
	{
	memset( &xParameters, '\0', sizeof( xParameters ) );
	xParameters.ulMemorySize = sdIOMAN_MEM_SIZE;
	xParameters.ulSectorSize = 512;
	xParameters.fnWriteBlocks = prvFFWrite;
	xParameters.fnReadBlocks = prvFFRead;
	xParameters.pxDisk = pxDisk;

	/* prvFFRead()/prvFFWrite() are not re-entrant and must be
	protected with the use of a semaphore. */
	xParameters.xBlockDeviceIsReentrant = pdFALSE;

	/* The semaphore will be used to protect critical sections in
	the +FAT driver, and also to avoid concurrent calls to
	prvFFRead()/prvFFWrite() from different tasks. */
	xParameters.pvSemaphore = ( void * ) xPlusFATMutex;

	pxDisk->pxIOManager = FF_CreateIOManger( &xParameters, &xFFError );

	if( pxDisk->pxIOManager == NULL )
	{
	FF_PRINTF( "FF_SDDiskInit: FF_CreateIOManger: %s\n", (const char*)FF_GetErrMessage( xFFError ) );
	FF_SDDiskDelete( pxDisk );
	pxDisk = NULL;
	}
	else
	{
	pxDisk->xStatus.bIsInitialised = pdTRUE;
	pxDisk->xStatus.bPartitionNumber = xPartitionNumber;
	if( FF_SDDiskMount( pxDisk ) == 0 )
	{
	FF_SDDiskDelete( pxDisk );
	pxDisk = NULL;
	}
	else
	{
	if( pcName == NULL )
	{
	pcName = "/";
	}
	FF_FS_Add( pcName, pxDisk );
	FF_PRINTF( "FF_SDDiskInit: Mounted SD-card as root \"%s\"\n", pcName );
	FF_SDDiskShowPartition( pxDisk );
	}
	} /* if( pxDisk->pxIOManager != NULL ) */
	} /* if( xPlusFATMutex != NULL) */
	} /* if( pxDisk != NULL ) */
	} /* if( xSDCardStatus == pdPASS ) */

	return pxDisk;
	}
	/-----------------------------------------------------------/

	BaseType_t FF_SDDiskFormat( FF_Disk_t *pxDisk, BaseType_t aPart )
	{
	FF_Error_t xError;
	BaseType_t xReturn = pdFAIL;

	xError = FF_Unmount( pxDisk );

	if( FF_isERR( xError ) != pdFALSE )
	{
	FF_PRINTF( "FF_SDDiskFormat: unmount fails: %08x\n", ( unsigned ) xError );
	}
	else
	{
	/* Format the drive - try FAT32 with large clusters. */
	xError = FF_Format( pxDisk, aPart, pdFALSE, pdFALSE);

	if( FF_isERR( xError ) )
	{
	FF_PRINTF( "FF_SDDiskFormat: %s\n", (const char*)FF_GetErrMessage( xError ) );
	}
	else
	{
	FF_PRINTF( "FF_SDDiskFormat: OK, now remounting\n" );
	pxDisk->xStatus.bPartitionNumber = aPart;
	xError = FF_SDDiskMount( pxDisk );
	FF_PRINTF( "FF_SDDiskFormat: rc %08x\n", ( unsigned )xError );
	if( FF_isERR( xError ) == pdFALSE )
	{
	xReturn = pdPASS;
	FF_SDDiskShowPartition( pxDisk );
	}
	}
	}

	return xReturn;
	}
	/-----------------------------------------------------------/

	BaseType_t FF_SDDiskUnmount( FF_Disk_t *pxDisk )
	{
	FF_Error_t xFFError;
	BaseType_t xReturn = pdPASS;

	if( ( pxDisk != NULL ) && ( pxDisk->xStatus.bIsMounted != pdFALSE ) )
	{
	pxDisk->xStatus.bIsMounted = pdFALSE;
	xFFError = FF_Unmount( pxDisk );

	if( FF_isERR( xFFError ) )
	{
	FF_PRINTF( "FF_SDDiskUnmount: rc %08x\n", ( unsigned )xFFError );
	xReturn = pdFAIL;
	}
	else
	{
	FF_PRINTF( "Drive unmounted\n" );
	}
	}

	return xReturn;
	}
	/-----------------------------------------------------------/

	BaseType_t FF_SDDiskReinit( FF_Disk_t *pxDisk )
	{
	BaseType_t xStatus = prvSDMMCInit( 0 ); /* Hard coded index. */

	/_RB_ parameter not used. /
	( void ) pxDisk;

	FF_PRINTF( "FF_SDDiskReinit: rc %08x\n", ( unsigned ) xStatus );
	return xStatus;
	}
	/-----------------------------------------------------------/

	BaseType_t FF_SDDiskMount( FF_Disk_t *pxDisk )
	{
	FF_Error_t xFFError;
	BaseType_t xReturn;

	/* Mount the partition */
	xFFError = FF_Mount( pxDisk, pxDisk->xStatus.bPartitionNumber );

	if( FF_isERR( xFFError ) )
	{
	FF_PRINTF( "FF_SDDiskMount: %08lX\n", xFFError );
	xReturn = pdFAIL;
	}
	else
	{
	pxDisk->xStatus.bIsMounted = pdTRUE;
	FF_PRINTF( "****** FreeRTOS+FAT initialized %lu sectors\n", pxDisk->pxIOManager->xPartition.ulTotalSectors );
	xReturn = pdPASS;
	}

	return xReturn;
	}
	/-----------------------------------------------------------/

	FF_IOManager_t sddisk_ioman( FF_Disk_t pxDisk )
	{
	FF_IOManager_t *pxReturn;

	if( ( pxDisk != NULL ) && ( pxDisk->xStatus.bIsInitialised != pdFALSE ) )
	{
	pxReturn = pxDisk->pxIOManager;
	}
	else
	{
	pxReturn = NULL;
	}
	return pxReturn;
	}
	/-----------------------------------------------------------/

	/* Release all resources */
	BaseType_t FF_SDDiskDelete( FF_Disk_t *pxDisk )
	{
	if( pxDisk != NULL )
	{
	pxDisk->ulSignature = 0;
	pxDisk->xStatus.bIsInitialised = 0;
	if( pxDisk->pxIOManager != NULL )
	{
	if( FF_Mounted( pxDisk->pxIOManager ) != pdFALSE )
	{
	FF_Unmount( pxDisk );
	}
	FF_DeleteIOManager( pxDisk->pxIOManager );
	}

	vPortFree( pxDisk );
	}
	return 1;
	}
	/-----------------------------------------------------------/

	BaseType_t FF_SDDiskShowPartition( FF_Disk_t *pxDisk )
	{
	FF_Error_t xError;
	uint64_t ullFreeSectors;
	uint32_t ulTotalSizeMB, ulFreeSizeMB;
	int iPercentageFree;
	FF_IOManager_t *pxIOManager;
	const char *pcTypeName = "unknown type";
	BaseType_t xReturn = pdPASS;

	if( pxDisk == NULL )
	{
	xReturn = pdFAIL;
	}
	else
	{
	pxIOManager = pxDisk->pxIOManager;

	FF_PRINTF( "Reading FAT and calculating Free Space\n" );

	switch( pxIOManager->xPartition.ucType )
	{
	case FF_T_FAT12:
	pcTypeName = "FAT12";
	break;

	case FF_T_FAT16:
	pcTypeName = "FAT16";
	break;

	case FF_T_FAT32:
	pcTypeName = "FAT32";
	break;

	default:
	pcTypeName = "UNKOWN";
	break;
	}

	FF_GetFreeSize( pxIOManager, &xError );

	ullFreeSectors = pxIOManager->xPartition.ulFreeClusterCount * pxIOManager->xPartition.ulSectorsPerCluster;
	iPercentageFree = ( int ) ( ( sdHUNDRED_64_BIT * ullFreeSectors + pxIOManager->xPartition.ulDataSectors / 2 ) /
	( ( uint64_t )pxIOManager->xPartition.ulDataSectors ) );

	ulTotalSizeMB = pxIOManager->xPartition.ulDataSectors / sdSECTORS_PER_MB;
	ulFreeSizeMB = ( uint32_t ) ( ullFreeSectors / sdSECTORS_PER_MB );

	/* It is better not to use the 64-bit format such as %Lu because it
	might not be implemented. */
	FF_PRINTF( "Partition Nr %8u\n", pxDisk->xStatus.bPartitionNumber );
	FF_PRINTF( "Type %8u (%s)\n", pxIOManager->xPartition.ucType, pcTypeName );
	FF_PRINTF( "VolLabel '%8s' \n", pxIOManager->xPartition.pcVolumeLabel );
	FF_PRINTF( "TotalSectors %8lu\n", pxIOManager->xPartition.ulTotalSectors );
	FF_PRINTF( "SecsPerCluster %8lu\n", pxIOManager->xPartition.ulSectorsPerCluster );
	FF_PRINTF( "Size %8lu MB\n", ulTotalSizeMB );
	FF_PRINTF( "FreeSize %8lu MB ( %d perc free )\n", ulFreeSizeMB, iPercentageFree );
	}

	return xReturn;
	}
	/-----------------------------------------------------------/

	BaseType_t FF_SDDiskDetect( FF_Disk_t *pxDisk )
	{
	BaseType_t xIsPresent;
	void *pvSemaphore;

	if( ( pxDisk != NULL ) &&
	( pxDisk->pxIOManager ) )
	{
	pvSemaphore = pxDisk->pxIOManager->pvSemaphore;
	}
	else
	{
	pvSemaphore = NULL;
	}

	/_RB_ Can these NULL checks be moved inside the FF_nnnSemaphore() functions? /
	/_HT_ I'm afraid not, both functions start with configASSERT( pxSemaphore ); /
	if( pvSemaphore != NULL )
	{
	FF_PendSemaphore( pvSemaphore );
	}

	xIsPresent = prvSDDetect();

	if( pvSemaphore != NULL )
	{
	FF_ReleaseSemaphore( pvSemaphore );
	}

	return xIsPresent;
	}
	/-----------------------------------------------------------/

	static BaseType_t prvSDDetect( void )
	{
	static BaseType_t xWasPresent;
	BaseType_t xIsPresent;
	sd_mmc_err_t xSDPresence;

	if( xWasPresent == pdFALSE )
	{
	/* Try to initialize SD MMC stack */
	sd_mmc_init();
	xSDPresence = sd_mmc_check( 0 );
	if( ( xSDPresence == SD_MMC_OK ) \|\| ( xSDPresence == SD_MMC_INIT_ONGOING ) )
	{
	xIsPresent = pdTRUE;
	}
	else
	{
	xIsPresent = pdFALSE;
	}
	}
	else
	{
	/* See if the card is still present. */
	xSDPresence = sd_mmc_check_status(0);
	if( xSDPresence == SD_MMC_OK )
	{
	xIsPresent = pdTRUE;
	}
	else
	{
	xIsPresent = pdFALSE;
	}
	}
	xWasPresent = xIsPresent;

	return xIsPresent;
	}
	/-----------------------------------------------------------/

	static BaseType_t prvSDMMCInit( BaseType_t xDriveNumber )
	{
	BaseType_t xReturn;

	/* 'xDriveNumber' not yet in use. */
	( void ) xDriveNumber;

	/* Check if the SD card is plugged in the slot */
	if( prvSDDetect() == pdFALSE )
	{
	FF_PRINTF( "No SD card detected\n" );
	xReturn = pdFAIL;
	}
	else
	{
	FF_PRINTF( "HAL_SD_Init: type: %s Capacity: %lu MB\n",
	xSDCardInfo.type & CARD_TYPE_HC ? "SDHC" : "SD",
	( xSDCardInfo.capacity << 1 ) / 2048 );

	xReturn = pdPASS;
	}

	return xReturn;
	}
	/-----------------------------------------------------------/