Demos/Device/LowLevel/MassStorage/MassStorage.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2009.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2009  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, and distribute this software
  13   and its documentation for any purpose and without fee is hereby
  14   granted, provided that the above copyright notice appear in all
  15   copies and that both that the copyright notice and this
  16   permission notice and warranty disclaimer appear in supporting
  17   documentation, and that the name of the author not be used in
  18   advertising or publicity pertaining to distribution of the
  19   software without specific, written prior permission.
  20
  21   The author disclaim all warranties with regard to this
  22   software, including all implied warranties of merchantability
  23   and fitness.  In no event shall the author be liable for any
  24   special, indirect or consequential damages or any damages
  25   whatsoever resulting from loss of use, data or profits, whether
  26   in an action of contract, negligence or other tortious action,
  27   arising out of or in connection with the use or performance of
  28   this software.
  29 */
  30
  31 /** \file
  32  *
  33  *  Main source file for the Mass Storage demo. This file contains the main tasks of the demo and
  34  *  is responsible for the initial application hardware configuration.
  35  */
  36
  37 #define  INCLUDE_FROM_MASSSTORAGE_C
  38 #include "MassStorage.h"
  39
  40 /* Global Variables */
  41 /** Structure to hold the latest Command Block Wrapper issued by the host, containing a SCSI command to execute. */
  42 CommandBlockWrapper_t  CommandBlock;
  43
  44 /** Structure to hold the latest Command Status Wrapper to return to the host, containing the status of the last issued command. */
  45 CommandStatusWrapper_t CommandStatus = { .Signature = CSW_SIGNATURE };
  46
  47 /** Flag to asynchronously abort any in-progress data transfers upon the reception of a mass storage reset command. */
  48 volatile bool          IsMassStoreReset = false;
  49
  50 /** Main program entry point. This routine configures the hardware required by the application, then
  51  *  starts the scheduler to run the application tasks.
  52  */
  53 int main(void)
  54 {
  55         SetupHardware();
  56
  57         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
  58
  59         for (;;)
  60         {
  61                 MassStorage_Task();
  62                 USB_USBTask();
  63         }
  64 }
  65
  66 /** Configures the board hardware and chip peripherals for the demo's functionality. */
  67 void SetupHardware(void)
  68 {
  69         /* Disable watchdog if enabled by bootloader/fuses */
  70         MCUSR &= ~(1 << WDRF);
  71         wdt_disable();
  72
  73         /* Disable clock division */
  74         clock_prescale_set(clock_div_1);
  75
  76         /* Hardware Initialization */
  77         LEDs_Init();
  78         Dataflash_Init(SPI_SPEED_FCPU_DIV_2);
  79         USB_Init();
  80
  81         /* Clear Dataflash sector protections, if enabled */
  82         DataflashManager_ResetDataflashProtections();
  83 }
  84
  85 /** Event handler for the USB_Connect event. This indicates that the device is enumerating via the status LEDs. */
  86 void EVENT_USB_Connect(void)
  87 {
  88         /* Indicate USB enumerating */
  89         LEDs_SetAllLEDs(LEDMASK_USB_ENUMERATING);
  90
  91         /* Reset the MSReset flag upon connection */
  92         IsMassStoreReset = false;
  93 }
  94
  95 /** Event handler for the USB_Disconnect event. This indicates that the device is no longer connected to a host via
  96  *  the status LEDs and stops the Mass Storage management task.
  97  */
  98 void EVENT_USB_Disconnect(void)
  99 {
 100         /* Indicate USB not ready */
 101         LEDs_SetAllLEDs(LEDMASK_USB_NOTREADY);
 102 }
 103
 104 /** Event handler for the USB_ConfigurationChanged event. This is fired when the host set the current configuration
 105  *  of the USB device after enumeration - the device endpoints are configured and the Mass Storage management task started.
 106  */
 107 void EVENT_USB_ConfigurationChanged(void)
 108 {
 109         /* Indicate USB connected and ready */
 110         LEDs_SetAllLEDs(LEDMASK_USB_READY);
 111
 112         /* Setup Mass Storage In and Out Endpoints */
 113         if (!(Endpoint_ConfigureEndpoint(MASS_STORAGE_IN_EPNUM, EP_TYPE_BULK,
 114                                              ENDPOINT_DIR_IN, MASS_STORAGE_IO_EPSIZE,
 115                                          ENDPOINT_BANK_DOUBLE)))
 116         {
 117                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 118         }
 119
 120         if (!(Endpoint_ConfigureEndpoint(MASS_STORAGE_OUT_EPNUM, EP_TYPE_BULK,
 121                                              ENDPOINT_DIR_OUT, MASS_STORAGE_IO_EPSIZE,
 122                                          ENDPOINT_BANK_DOUBLE)))
 123         {
 124                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 125         }
 126 }
 127
 128 /** Event handler for the USB_UnhandledControlPacket event. This is used to catch standard and class specific
 129  *  control requests that are not handled internally by the USB library (including the Mass Storage class-specific
 130  *  requests) so that they can be handled appropriately for the application.
 131  */
 132 void EVENT_USB_UnhandledControlPacket(void)
 133 {
 134         /* Process UFI specific control requests */
 135         switch (USB_ControlRequest.bRequest)
 136         {
 137                 case REQ_MassStorageReset:
 138                         if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE))
 139                         {
 140                                 Endpoint_ClearSETUP();
 141
 142                                 /* Indicate that the current transfer should be aborted */
 143                                 IsMassStoreReset = true;
 144
 145                                 /* Acknowledge status stage */
 146                                 while (!(Endpoint_IsINReady()));
 147                                 Endpoint_ClearIN();
 148                         }
 149
 150                         break;
 151                 case REQ_GetMaxLUN:
 152                         if (USB_ControlRequest.bmRequestType == (REQDIR_DEVICETOHOST | REQTYPE_CLASS | REQREC_INTERFACE))
 153                         {
 154                                 Endpoint_ClearSETUP();
 155
 156                                 /* Indicate to the host the number of supported LUNs (virtual disks) on the device */
 157                                 Endpoint_Write_Byte(TOTAL_LUNS - 1);
 158
 159                                 Endpoint_ClearIN();
 160
 161                                 /* Acknowledge status stage */
 162                                 while (!(Endpoint_IsOUTReceived()));
 163                                 Endpoint_ClearOUT();
 164                         }
 165
 166                         break;
 167         }
 168 }
 169
 170 /** Task to manage the Mass Storage interface, reading in Command Block Wrappers from the host, processing the SCSI commands they
 171  *  contain, and returning Command Status Wrappers back to the host to indicate the success or failure of the last issued command.
 172  */
 173 void MassStorage_Task(void)
 174 {
 175         /* Check if the USB System is connected to a Host */
 176         if (USB_IsConnected)
 177         {
 178                 /* Select the Data Out Endpoint */
 179                 Endpoint_SelectEndpoint(MASS_STORAGE_OUT_EPNUM);
 180
 181                 /* Check to see if a command from the host has been issued */
 182                 if (Endpoint_IsReadWriteAllowed())
 183                 {
 184                         /* Indicate busy */
 185                         LEDs_SetAllLEDs(LEDMASK_USB_BUSY);
 186
 187                         /* Process sent command block from the host */
 188                         if (ReadInCommandBlock())
 189                         {
 190                                 /* Check direction of command, select Data IN endpoint if data is from the device */
 191                                 if (CommandBlock.Flags & COMMAND_DIRECTION_DATA_IN)
 192                                   Endpoint_SelectEndpoint(MASS_STORAGE_IN_EPNUM);
 193
 194                                 /* Decode the received SCSI command */
 195                                 SCSI_DecodeSCSICommand();
 196
 197                                 /* Load in the CBW tag into the CSW to link them together */
 198                                 CommandStatus.Tag = CommandBlock.Tag;
 199
 200                                 /* Load in the data residue counter into the CSW */
 201                                 CommandStatus.DataTransferResidue = CommandBlock.DataTransferLength;
 202
 203                                 /* Stall the selected data pipe if command failed (if data is still to be transferred) */
 204                                 if ((CommandStatus.Status == Command_Fail) && (CommandStatus.DataTransferResidue))
 205                                   Endpoint_StallTransaction();
 206
 207                                 /* Return command status block to the host */
 208                                 ReturnCommandStatus();
 209
 210                                 /* Check if a Mass Storage Reset occurred */
 211                                 if (IsMassStoreReset)
 212                                 {
 213                                         /* Reset the data endpoint banks */
 214                                         Endpoint_ResetFIFO(MASS_STORAGE_OUT_EPNUM);
 215                                         Endpoint_ResetFIFO(MASS_STORAGE_IN_EPNUM);
 216
 217                                         Endpoint_SelectEndpoint(MASS_STORAGE_OUT_EPNUM);
 218                                         Endpoint_ClearStall();
 219                                         Endpoint_SelectEndpoint(MASS_STORAGE_IN_EPNUM);
 220                                         Endpoint_ClearStall();
 221
 222                                         /* Clear the abort transfer flag */
 223                                         IsMassStoreReset = false;
 224                                 }
 225
 226                                 /* Indicate ready */
 227                                 LEDs_SetAllLEDs(LEDMASK_USB_READY);
 228                         }
 229                         else
 230                         {
 231                                 /* Indicate error reading in the command block from the host */
 232                                 LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 233                         }
 234                 }
 235         }
 236 }
 237
 238 /** Function to read in a command block from the host, via the bulk data OUT endpoint. This function reads in the next command block
 239  *  if one has been issued, and performs validation to ensure that the block command is valid.
 240  *
 241  *  \return Boolean true if a valid command block has been read in from the endpoint, false otherwise
 242  */
 243 static bool ReadInCommandBlock(void)
 244 {
 245         /* Select the Data Out endpoint */
 246         Endpoint_SelectEndpoint(MASS_STORAGE_OUT_EPNUM);
 247
 248         /* Read in command block header */
 249         Endpoint_Read_Stream_LE(&CommandBlock, (sizeof(CommandBlock) - sizeof(CommandBlock.SCSICommandData)),
 250                                 StreamCallback_AbortOnMassStoreReset);
 251
 252         /* Check if the current command is being aborted by the host */
 253         if (IsMassStoreReset)
 254           return false;
 255
 256         /* Verify the command block - abort if invalid */
 257         if ((CommandBlock.Signature != CBW_SIGNATURE) ||
 258             (CommandBlock.LUN >= TOTAL_LUNS) ||
 259                 (CommandBlock.SCSICommandLength > MAX_SCSI_COMMAND_LENGTH))
 260         {
 261                 /* Stall both data pipes until reset by host */
 262                 Endpoint_StallTransaction();
 263                 Endpoint_SelectEndpoint(MASS_STORAGE_IN_EPNUM);
 264                 Endpoint_StallTransaction();
 265
 266                 return false;
 267         }
 268
 269         /* Read in command block command data */
 270         Endpoint_Read_Stream_LE(&CommandBlock.SCSICommandData,
 271                                 CommandBlock.SCSICommandLength,
 272                                 StreamCallback_AbortOnMassStoreReset);
 273
 274         /* Check if the current command is being aborted by the host */
 275         if (IsMassStoreReset)
 276           return false;
 277
 278         /* Finalize the stream transfer to send the last packet */
 279         Endpoint_ClearOUT();
 280
 281         return true;
 282 }
 283
 284 /** Returns the filled Command Status Wrapper back to the host via the bulk data IN endpoint, waiting for the host to clear any
 285  *  stalled data endpoints as needed.
 286  */
 287 static void ReturnCommandStatus(void)
 288 {
 289         /* Select the Data Out endpoint */
 290         Endpoint_SelectEndpoint(MASS_STORAGE_OUT_EPNUM);
 291
 292         /* While data pipe is stalled, wait until the host issues a control request to clear the stall */
 293         while (Endpoint_IsStalled())
 294         {
 295                 /* Check if the current command is being aborted by the host */
 296                 if (IsMassStoreReset)
 297                   return;
 298         }
 299
 300         /* Select the Data In endpoint */
 301         Endpoint_SelectEndpoint(MASS_STORAGE_IN_EPNUM);
 302
 303         /* While data pipe is stalled, wait until the host issues a control request to clear the stall */
 304         while (Endpoint_IsStalled())
 305         {
 306                 /* Check if the current command is being aborted by the host */
 307                 if (IsMassStoreReset)
 308                   return;
 309         }
 310
 311         /* Write the CSW to the endpoint */
 312         Endpoint_Write_Stream_LE(&CommandStatus, sizeof(CommandStatus),
 313                                   StreamCallback_AbortOnMassStoreReset);
 314
 315         /* Check if the current command is being aborted by the host */
 316         if (IsMassStoreReset)
 317           return;
 318
 319         /* Finalize the stream transfer to send the last packet */
 320         Endpoint_ClearIN();
 321 }
 322
 323 /** Stream callback function for the Endpoint stream read and write functions. This callback will abort the current stream transfer
 324  *  if a Mass Storage Reset request has been issued to the control endpoint.
 325  */
 326 uint8_t StreamCallback_AbortOnMassStoreReset(void)
 327 {
 328         /* Abort if a Mass Storage reset command was received */
 329         if (IsMassStoreReset)
 330           return STREAMCALLBACK_Abort;
 331
 332         /* Continue with the current stream operation */
 333         return STREAMCALLBACK_Continue;
 334 }