USBMSD.h

00001 /* Copyright (c) 2010-2011 mbed.org, MIT License
00002 *
00003 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
00004 * and associated documentation files (the "Software"), to deal in the Software without
00005 * restriction, including without limitation the rights to use, copy, modify, merge, publish,
00006 * distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the
00007 * Software is furnished to do so, subject to the following conditions:
00008 *
00009 * The above copyright notice and this permission notice shall be included in all copies or
00010 * substantial portions of the Software.
00011 *
00012 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
00013 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
00014 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
00015 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00016 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
00017 */
00018 
00019 
00020 #ifndef USBMSD_H
00021 #define USBMSD_H
00022 
00023 /* These headers are included for child class. */
00024 #include "USBEndpoints.h"
00025 #include "USBDescriptor.h"
00026 #include "USBDevice_Types.h"
00027 
00028 #include "USBDevice.h"
00029 
00030 /**
00031  * USBMSD class: generic class in order to use all kinds of blocks storage chip
00032  *
00033  * Introduction
00034  *
00035  * The USBMSD implements the MSD protocol. It permits to access a memory chip (flash, sdcard,...)
00036  * from a computer over USB. But this class doesn't work standalone, you need to subclass this class
00037  * and define virtual functions which are called in USBMSD.
00038  *
00039  * How to use this class with your chip ?
00040  *
00041  * You have to inherit and define some pure virtual functions (mandatory step):
00042  *   - virtual int disk_read(char * data, int block): function to read a block
00043  *   - virtual int disk_write(const char * data, int block): function to write a block
00044  *   - virtual int disk_initialize(): function to initialize the memory
00045  *   - virtual int disk_sectors(): return the number of blocks
00046  *   - virtual int disk_size(): return the memory size
00047  *   - virtual int disk_status(): return the status of the storage chip (0: OK, 1: not initialized, 2: no medium in the drive, 4: write protection)
00048  *
00049  * All functions names are compatible with the fat filesystem library. So you can imagine using your own class with
00050  * USBMSD and the fat filesystem library in the same program. Just be careful because there are two different parts which
00051  * will access the sd card. You can do a master/slave system using the disk_status method.
00052  *
00053  * Once these functions defined, you can call connect() (at the end of the constructor of your class for instance)
00054  * of USBMSD to connect your mass storage device. connect() will first call disk_status() to test the status of the disk.
00055  * If disk_status() returns 1 (disk not initialized), then disk_initialize() is called. After this step, connect() will collect information
00056  * such as the number of blocks and the memory size.
00057  */
00058 class USBMSD: public USBDevice {
00059 public:
00060 
00061     /**
00062     * Constructor
00063     *
00064     * @param vendor_id Your vendor_id
00065     * @param product_id Your product_id
00066     * @param product_release Your preoduct_release
00067     */
00068     USBMSD(uint16_t vendor_id = 0x0703, uint16_t product_id = 0x0104, uint16_t product_release = 0x0001);
00069 
00070     /**
00071     * Connect the USB MSD device. Establish disk initialization before really connect the device.
00072     *
00073     * @returns true if successful
00074     */
00075     bool connect();
00076 
00077     /**
00078     * Disconnect the USB MSD device.
00079     */
00080     void disconnect();
00081     
00082     /**
00083     * Destructor
00084     */
00085     ~USBMSD();
00086 
00087 protected:
00088 
00089     /*
00090     * read a block on a storage chip
00091     *
00092     * @param data pointer where will be stored read data
00093     * @param block block number
00094     * @returns 0 if successful
00095     */
00096     virtual int disk_read(uint8_t * data, uint64_t block) = 0;
00097 
00098     /*
00099     * write a block on a storage chip
00100     *
00101     * @param data data to write
00102     * @param block block number
00103     * @returns 0 if successful
00104     */
00105     virtual int disk_write(const uint8_t * data, uint64_t block) = 0;
00106 
00107     /*
00108     * Disk initilization
00109     */
00110     virtual int disk_initialize() = 0;
00111 
00112     /*
00113     * Return the number of blocks
00114     *
00115     * @returns number of blocks
00116     */
00117     virtual uint64_t disk_sectors() = 0;
00118 
00119     /*
00120     * Return memory size
00121     *
00122     * @returns memory size
00123     */
00124     virtual uint64_t disk_size() = 0;
00125 
00126 
00127     /*
00128     * To check the status of the storage chip
00129     *
00130     * @returns status: 0: OK, 1: disk not initialized, 2: no medium in the drive, 4: write protected
00131     */
00132     virtual int disk_status() = 0;
00133 
00134     /*
00135     * Get string product descriptor
00136     *
00137     * @returns pointer to the string product descriptor
00138     */
00139     virtual uint8_t * stringIproductDesc();
00140 
00141     /*
00142     * Get string interface descriptor
00143     *
00144     * @returns pointer to the string interface descriptor
00145     */
00146     virtual uint8_t * stringIinterfaceDesc();
00147 
00148     /*
00149     * Get configuration descriptor
00150     *
00151     * @returns pointer to the configuration descriptor
00152     */
00153     virtual uint8_t * configurationDesc();
00154 
00155     /*
00156     * Callback called when a packet is received
00157     */
00158     virtual bool EP2_OUT_callback();
00159 
00160     /*
00161     * Callback called when a packet has been sent
00162     */
00163     virtual bool EP2_IN_callback();
00164 
00165     /*
00166     * Set configuration of device. Add endpoints
00167     */
00168     virtual bool USBCallback_setConfiguration(uint8_t configuration);
00169 
00170     /*
00171     * Callback called to process class specific requests
00172     */
00173     virtual bool USBCallback_request();
00174 
00175 
00176 private:
00177 
00178     // MSC Bulk-only Stage
00179     enum Stage {
00180         READ_CBW,     // wait a CBW
00181         ERROR,        // error
00182         PROCESS_CBW,  // process a CBW request
00183         SEND_CSW,     // send a CSW
00184         WAIT_CSW,     // wait that a CSW has been effectively sent
00185     };
00186 
00187     // Bulk-only CBW
00188     typedef struct {
00189         uint32_t Signature;
00190         uint32_t Tag;
00191         uint32_t DataLength;
00192         uint8_t  Flags;
00193         uint8_t  LUN;
00194         uint8_t  CBLength;
00195         uint8_t  CB[16];
00196     } PACKED CBW;
00197 
00198     // Bulk-only CSW
00199     typedef struct {
00200         uint32_t Signature;
00201         uint32_t Tag;
00202         uint32_t DataResidue;
00203         uint8_t  Status;
00204     } PACKED CSW;
00205 
00206     //state of the bulk-only state machine
00207     Stage stage;
00208 
00209     // current CBW
00210     CBW cbw;
00211 
00212     // CSW which will be sent
00213     CSW csw;
00214 
00215     // addr where will be read or written data
00216     uint32_t addr;
00217 
00218     // length of a reading or writing
00219     uint32_t length;
00220 
00221     // memory OK (after a memoryVerify)
00222     bool memOK;
00223 
00224     // cache in RAM before writing in memory. Useful also to read a block.
00225     uint8_t * page;
00226 
00227     int BlockSize;
00228     uint64_t MemorySize;
00229     uint64_t BlockCount;
00230 
00231     void CBWDecode(uint8_t * buf, uint16_t size);
00232     void sendCSW (void);
00233     bool inquiryRequest (void);
00234     bool write (uint8_t * buf, uint16_t size);
00235     bool readFormatCapacity();
00236     bool readCapacity (void);
00237     bool infoTransfer (void);
00238     void memoryRead (void);
00239     bool modeSense6 (void);
00240     void testUnitReady (void);
00241     bool requestSense (void);
00242     void memoryVerify (uint8_t * buf, uint16_t size);
00243     void memoryWrite (uint8_t * buf, uint16_t size);
00244     void reset();
00245     void fail();
00246 };
00247 
00248 #endif