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 protected:
00079 
00080     /*
00081     * read a block on a storage chip
00082     *
00083     * @param data pointer where will be stored read data
00084     * @param block block number
00085     * @returns 0 if successful
00086     */
00087     virtual int disk_read(char * data, int block) = 0;
00088 
00089     /*
00090     * write a block on a storage chip
00091     *
00092     * @param data data to write
00093     * @param block block number
00094     * @returns 0 if successful
00095     */
00096     virtual int disk_write(const char * data, int block) = 0;
00097 
00098     /*
00099     * Disk initilization
00100     */
00101     virtual int disk_initialize() = 0;
00102 
00103     /*
00104     * Return the number of blocks
00105     *
00106     * @returns number of blocks
00107     */
00108     virtual int disk_sectors() = 0;
00109 
00110     /*
00111     * Return memory size
00112     *
00113     * @returns memory size
00114     */
00115     virtual int disk_size() = 0;
00116 
00117 
00118     /*
00119     * To check the status of the storage chip
00120     *
00121     * @returns status: 0: OK, 1: disk not initialized, 2: no medium in the drive, 4: write protected
00122     */
00123     virtual int disk_status() = 0;
00124 
00125     /*
00126     * Get string product descriptor
00127     *
00128     * @returns pointer to the string product descriptor
00129     */
00130     virtual uint8_t * stringIproductDesc();
00131 
00132     /*
00133     * Get string interface descriptor
00134     *
00135     * @returns pointer to the string interface descriptor
00136     */
00137     virtual uint8_t * stringIinterfaceDesc();
00138 
00139     /*
00140     * Get configuration descriptor
00141     *
00142     * @returns pointer to the configuration descriptor
00143     */
00144     virtual uint8_t * configurationDesc();
00145 
00146     /*
00147     * Callback called when a packet is received
00148     */
00149     virtual bool EP2_OUT_callback();
00150 
00151     /*
00152     * Callback called when a packet has been sent
00153     */
00154     virtual bool EP2_IN_callback();
00155 
00156     /*
00157     * Set configuration of device. Add endpoints
00158     */
00159     virtual bool USBCallback_setConfiguration(uint8_t configuration);
00160 
00161     /*
00162     * Callback called to process class specific requests
00163     */
00164     virtual bool USBCallback_request();
00165 
00166 
00167 private:
00168 
00169     // MSC Bulk-only Stage
00170     enum Stage {
00171         READ_CBW,     // wait a CBW
00172         ERROR,        // error
00173         PROCESS_CBW,  // process a CBW request
00174         SEND_CSW,     // send a CSW
00175         WAIT_CSW,     // wait that a CSW has been effectively sent
00176     };
00177 
00178     // Bulk-only CBW
00179     typedef __packed struct {
00180         uint32_t Signature;
00181         uint32_t Tag;
00182         uint32_t DataLength;
00183         uint8_t  Flags;
00184         uint8_t  LUN;
00185         uint8_t  CBLength;
00186         uint8_t  CB[16];
00187     } CBW;
00188 
00189     // Bulk-only CSW
00190     typedef __packed struct {
00191         uint32_t Signature;
00192         uint32_t Tag;
00193         uint32_t DataResidue;
00194         uint8_t  Status;
00195     } CSW;
00196 
00197     //state of the bulk-only state machine
00198     Stage stage;
00199 
00200     // current CBW
00201     CBW cbw;
00202 
00203     // CSW which will be sent
00204     CSW csw;
00205 
00206     // addr where will be read or written data
00207     uint32_t addr;
00208 
00209     // length of a reading or writing
00210     uint32_t length;
00211 
00212     // memory OK (after a memoryVerify)
00213     bool memOK;
00214 
00215     // cache in RAM before writing in memory. Useful also to read a block.
00216     uint8_t * page;
00217 
00218     int BlockSize;
00219     int MemorySize;
00220     int BlockCount;
00221 
00222     void CBWDecode(uint8_t * buf, uint16_t size);
00223     void sendCSW (void);
00224     bool inquiryRequest (void);
00225     bool write (uint8_t * buf, uint16_t size);
00226     bool readFormatCapacity();
00227     bool readCapacity (void);
00228     bool infoTransfer (void);
00229     void memoryRead (void);
00230     bool modeSense6 (void);
00231     void testUnitReady (void);
00232     bool requestSense (void);
00233     void memoryVerify (uint8_t * buf, uint16_t size);
00234     void memoryWrite (uint8_t * buf, uint16_t size);
00235     void reset();
00236     void fail();
00237 };
00238 
00239 #endif