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                                 Endpoint_ClearStatusStage();
 146                         }
 147
 148                         break;
 149                 case REQ_GetMaxLUN:
 150                         if (USB_ControlRequest.bmRequestType == (REQDIR_DEVICETOHOST | REQTYPE_CLASS | REQREC_INTERFACE))
 151                         {
 152                                 Endpoint_ClearSETUP();
 153
 154                                 /* Indicate to the host the number of supported LUNs (virtual disks) on the device */
 155                                 Endpoint_Write_Byte(TOTAL_LUNS - 1);
 156
 157                                 Endpoint_ClearIN();
 158
 159                                 Endpoint_ClearStatusStage();
 160                         }
 161
 162                         break;
 163         }
 164 }
 165
 166 /** Task to manage the Mass Storage interface, reading in Command Block Wrappers from the host, processing the SCSI commands they
 167  *  contain, and returning Command Status Wrappers back to the host to indicate the success or failure of the last issued command.
 168  */
 169 void MassStorage_Task(void)
 170 {
 171         /* Device must be connected and configured for the task to run */
 172         if (USB_DeviceState != DEVICE_STATE_Configured)
 173           return;
 174
 175         /* Select the Data Out Endpoint */
 176         Endpoint_SelectEndpoint(MASS_STORAGE_OUT_EPNUM);
 177
 178         /* Check to see if a command from the host has been issued */
 179         if (Endpoint_IsReadWriteAllowed())
 180         {
 181                 /* Indicate busy */
 182                 LEDs_SetAllLEDs(LEDMASK_USB_BUSY);
 183
 184                 /* Process sent command block from the host */
 185                 if (ReadInCommandBlock())
 186                 {
 187                         /* Check direction of command, select Data IN endpoint if data is from the device */
 188                         if (CommandBlock.Flags & COMMAND_DIRECTION_DATA_IN)
 189                           Endpoint_SelectEndpoint(MASS_STORAGE_IN_EPNUM);
 190
 191                         /* Decode the received SCSI command */
 192                         SCSI_DecodeSCSICommand();
 193
 194                         /* Load in the CBW tag into the CSW to link them together */
 195                         CommandStatus.Tag = CommandBlock.Tag;
 196
 197                         /* Load in the data residue counter into the CSW */
 198                         CommandStatus.DataTransferResidue = CommandBlock.DataTransferLength;
 199
 200                         /* Stall the selected data pipe if command failed (if data is still to be transferred) */
 201                         if ((CommandStatus.Status == Command_Fail) && (CommandStatus.DataTransferResidue))
 202                           Endpoint_StallTransaction();
 203
 204                         /* Return command status block to the host */
 205                         ReturnCommandStatus();
 206
 207                         /* Check if a Mass Storage Reset occurred */
 208                         if (IsMassStoreReset)
 209                         {
 210                                 /* Reset the data endpoint banks */
 211                                 Endpoint_ResetFIFO(MASS_STORAGE_OUT_EPNUM);
 212                                 Endpoint_ResetFIFO(MASS_STORAGE_IN_EPNUM);
 213
 214                                 Endpoint_SelectEndpoint(MASS_STORAGE_OUT_EPNUM);
 215                                 Endpoint_ClearStall();
 216                                 Endpoint_SelectEndpoint(MASS_STORAGE_IN_EPNUM);
 217                                 Endpoint_ClearStall();
 218                         }
 219
 220                         /* Indicate ready */
 221                         LEDs_SetAllLEDs(LEDMASK_USB_READY);
 222                 }
 223                 else
 224                 {
 225                         /* Indicate error reading in the command block from the host */
 226                         LEDs_SetAllLEDs(LEDMASK_USB_ERROR);
 227                 }
 228         }
 229
 230         /* Clear the abort transfer flag */
 231         IsMassStoreReset = false;
 232 }
 233
 234 /** Function to read in a command block from the host, via the bulk data OUT endpoint. This function reads in the next command block
 235  *  if one has been issued, and performs validation to ensure that the block command is valid.
 236  *
 237  *  \return Boolean true if a valid command block has been read in from the endpoint, false otherwise
 238  */
 239 static bool ReadInCommandBlock(void)
 240 {
 241         /* Select the Data Out endpoint */
 242         Endpoint_SelectEndpoint(MASS_STORAGE_OUT_EPNUM);
 243
 244         /* Read in command block header */
 245         Endpoint_Read_Stream_LE(&CommandBlock, (sizeof(CommandBlock) - sizeof(CommandBlock.SCSICommandData)),
 246                                 StreamCallback_AbortOnMassStoreReset);
 247
 248         /* Check if the current command is being aborted by the host */
 249         if (IsMassStoreReset)
 250           return false;
 251
 252         /* Verify the command block - abort if invalid */
 253         if ((CommandBlock.Signature         != CBW_SIGNATURE) ||
 254             (CommandBlock.LUN               >= TOTAL_LUNS)    ||
 255                 (CommandBlock.Flags              & 0x1F)          ||
 256                 (CommandBlock.SCSICommandLength == 0)             ||
 257                 (CommandBlock.SCSICommandLength >  MAX_SCSI_COMMAND_LENGTH))
 258         {
 259                 /* Stall both data pipes until reset by host */
 260                 Endpoint_StallTransaction();
 261                 Endpoint_SelectEndpoint(MASS_STORAGE_IN_EPNUM);
 262                 Endpoint_StallTransaction();
 263
 264                 return false;
 265         }
 266
 267         /* Read in command block command data */
 268         Endpoint_Read_Stream_LE(&CommandBlock.SCSICommandData,
 269                                 CommandBlock.SCSICommandLength,
 270                                 StreamCallback_AbortOnMassStoreReset);
 271
 272         /* Check if the current command is being aborted by the host */
 273         if (IsMassStoreReset)
 274           return false;
 275
 276         /* Finalize the stream transfer to send the last packet */
 277         Endpoint_ClearOUT();
 278
 279         return true;
 280 }
 281
 282 /** Returns the filled Command Status Wrapper back to the host via the bulk data IN endpoint, waiting for the host to clear any
 283  *  stalled data endpoints as needed.
 284  */
 285 static void ReturnCommandStatus(void)
 286 {
 287         /* Select the Data Out endpoint */
 288         Endpoint_SelectEndpoint(MASS_STORAGE_OUT_EPNUM);
 289
 290         /* While data pipe is stalled, wait until the host issues a control request to clear the stall */
 291         while (Endpoint_IsStalled())
 292         {
 293                 /* Check if the current command is being aborted by the host */
 294                 if (IsMassStoreReset)
 295                   return;
 296         }
 297
 298         /* Select the Data In endpoint */
 299         Endpoint_SelectEndpoint(MASS_STORAGE_IN_EPNUM);
 300
 301         /* While data pipe is stalled, wait until the host issues a control request to clear the stall */
 302         while (Endpoint_IsStalled())
 303         {
 304                 /* Check if the current command is being aborted by the host */
 305                 if (IsMassStoreReset)
 306                   return;
 307         }
 308
 309         /* Write the CSW to the endpoint */
 310         Endpoint_Write_Stream_LE(&CommandStatus, sizeof(CommandStatus),
 311                                   StreamCallback_AbortOnMassStoreReset);
 312
 313         /* Check if the current command is being aborted by the host */
 314         if (IsMassStoreReset)
 315           return;
 316
 317         /* Finalize the stream transfer to send the last packet */
 318         Endpoint_ClearIN();
 319 }
 320
 321 /** Stream callback function for the Endpoint stream read and write functions. This callback will abort the current stream transfer
 322  *  if a Mass Storage Reset request has been issued to the control endpoint.
 323  */
 324 uint8_t StreamCallback_AbortOnMassStoreReset(void)
 325 {
 326         /* Abort if a Mass Storage reset command was received */
 327         if (IsMassStoreReset)
 328           return STREAMCALLBACK_Abort;
 329
 330         /* Continue with the current stream operation */
 331         return STREAMCALLBACK_Continue;
 332 }