1 /*

     2 * Copyright (c) 2007 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:  State machine

    15 *

    16 */

    17 

    18 

    19 #ifndef CSTATEMACHINE_H

    20 #define CSTATEMACHINE_H

    21 

    22 class CRequestsHandler;

    23 class CEP0Reader;

    24 class CEP0Writer;

    25 

    26 /**

    27  *  State machine for the control transfers

    28  *  Switches usbdevcon states between Setup-Data-Status

    29  *

    30  *  @lib usbdevcon.lib

    31  *  @since S60 v.5.0 

    32  */

    33  

    34 class CStateMachine : public CBase 

    35     {

    36 

    37 public:

    38 

    39     /**  States */

    40     enum TState

    41     {

    42         ENoneState,     // State is not defined 

    43         ESetupStage,    // ready for getting control setup transaction

    44         EDataStage,     // reading data from host, in Data stage        

    45         EStatusStage    // waiting for Status transaction, after writing data to host

    46     };

    47 

    48      /**

    49      * Two-phased constructor.

    50      *

    51      * @since S60 v.5.0

    52      * @param aRequestHandler Handles requests

    53      * @param aLdd Link to LDD services

    54      * @return Constructed instance

    55      */ 

    56     static CStateMachine* NewL(CRequestsHandler& aRequestsHandler, RDevUsbcClient& aLdd);

    57     

    58     /**

    59     * Destructor.

    60     *

    61     * @since S60 v.5.0

    62     */

    63     virtual ~CStateMachine();

    64     

    65     /**

    66      * Call back from CEP0Reader

    67      *

    68      * @since S60 v.5.0

    69      * @param aBuffer Data read from EP0

    70      * @param aStatus status of Read request, completed

    71      */

    72     void ReadEP0(RBuf8& aBuffer, const TRequestStatus& aStatus);

    73     

    74     /**

    75      * Call back from CEP0Writer

    76      *

    77      * @since S60 v.5.0

    78      * @param aStatus status of Write request, completed

    79      */

    80     void WroteEP0(const TRequestStatus& aStatus);

    81     

    82     /**

    83      * Starts machine

    84      *

    85      * @since S60 v.5.0

    86      */

    87     void Start();

    88     

    89     /**

    90      * Stops machine

    91      *

    92      * @since S60 v.5.0

    93      */

    94     void Stop();

    95     

    96     /**

    97      * Machine is started

    98      *

    99      * @since S60 v.5.0

   100      * @return ETrue if state machine is started

   101      */

   102     TBool IsStarted() const;

   103     

   104 private:

   105     

   106     /**

   107      * Default construction

   108      *

   109      * @since S60 v.5.0

   110      * @param aRequestHandler Handles requests

   111      * @param aLdd Link to LDD services

   112      */

   113     CStateMachine(CRequestsHandler& aRequestsHandler, RDevUsbcClient& aLdd);

   114     

   115     /**

   116      * Two-phased constructor.

   117      *

   118      * @since S60 v.5.0

   119      */

   120     void ConstructL();

   121     

   122     /**

   123      * Process setup packet

   124      *

   125      * @since S60 v.5.0

   126      * @param aSetupPacket Will be processed

   127      */

   128     void ProcessSetupPacket(RBuf8& aSetupPacket);

   129     

   130     /**

   131      * Checks wheather data required to be sent from host to device 

   132      *

   133      * @since S60 v.5.0

   134      * @param aSetupPacket Contains data direction bit, and length of data

   135      * @param aDataLength Length of data to be sent

   136      * @return ETrue If data stage is required

   137      */

   138     TBool IsDataFromHostRequired(const RBuf8& aSetupPacket, TUint& aDatalength) const;

   139     

   140     /**

   141      * Checks wheather data required to be sent from device to host

   142      *

   143      * @since S60 v.5.0

   144      * @param aSetupPacket Contains data direction bit, and length of data

   145      * @param aDataLength Length of data to be sent

   146      * @return ETrue If data stage is required

   147      */

   148     TBool IsDataFromDeviceRequired(const RBuf8& aSetupPacket, TUint& aDatalength) const;

   149     

   150 private: // data

   151     

   152     /**

   153      * EP0 reader

   154      * Own.  

   155      */

   156     CEP0Reader* iEP0Reader;

   157     

   158     /**

   159      * EP0 writer

   160      * Own.  

   161      */

   162     CEP0Writer* iEP0Writer;

   163     

   164     /**

   165      * Requests handler

   166      * Not own.  

   167      */

   168     CRequestsHandler& iRequestsHandler;

   169     

   170     /**

   171      * LDD

   172      * Not own.  

   173      */

   174     RDevUsbcClient& iLdd;

   175     

   176     /**

   177      * State

   178      */

   179     TState iState;

   180     

   181     /**

   182      * Buffer to keep request, if needed to receive data from host in Data stage

   183      * In case if request require data to be send from device to host,

   184      * iBuffer keeps result of that request

   185      */

   186     RBuf8 iBuffer;

   187         

   188     };

   189 

   190 #endif // CSTATEMACHINE_H