Demos/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 /* Project Tags, for reading out using the ButtLoad project */
  41 BUTTLOADTAG(ProjName,    "LUFA MassStore App");
  42 BUTTLOADTAG(BuildTime,   __TIME__);
  43 BUTTLOADTAG(BuildDate,   __DATE__);
  44 BUTTLOADTAG(LUFAVersion, "LUFA V" LUFA_VERSION_STRING);
  45
  46 /* Scheduler Task List */
  47 TASK_LIST
  48 {
  49         { Task: USB_MassStorage      , TaskStatus: TASK_STOP },
  50 };
  51
  52 /* Global Variables */
  53 /** Structure to hold the latest Command Block Wrapper issued by the host, containing a SCSI command to execute. */
  54 CommandBlockWrapper_t  CommandBlock;
  55
  56 /** Structure to hold the latest Command Status Wrapper to return to the host, containing the status of the last issued command. */
  57 CommandStatusWrapper_t CommandStatus = { Signature: CSW_SIGNATURE };
  58
  59 /** Flag to asyncronously abort any in-progress data transfers upon the reception of a mass storage reset command. */
  60 volatile bool          IsMassStoreReset = false;
  61
  62 /** Main program entry point. This routine configures the hardware required by the application, then
  63  *  starts the scheduler to run the application tasks.
  64  */
  65 int main(void)
  66 {
  67         /* Disable watchdog if enabled by bootloader/fuses */
  68         MCUSR &= ~(1 << WDRF);
  69         wdt_disable();
  70
  71         /* Disable Clock Division */
  72         SetSystemClockPrescaler(0);
  73
  74         /* Hardware Initialization */
  75         LEDs_Init();
  76         Dataflash_Init(SPI_SPEED_FCPU_DIV_2);
  77
  78         /* Clear Dataflash sector protections, if enabled */
  79         DataflashManager_ResetDataflashProtections();
  80
  81         /* Indicate USB not ready */
  82         UpdateStatus(Status_USBNotReady);
  83
  84         /* Initialize Scheduler so that it can be used */
  85         Scheduler_Init();
  86
  87         /* Initialize USB Subsystem */
  88         USB_Init();
  89
  90         /* Scheduling - routine never returns, so put this last in the main function */
  91         Scheduler_Start();
  92 }
  93
  94 /** Event handler for the USB_Reset event. This fires when the USB interface is reset by the USB host, before the
  95  *  enumeration process begins, and enables the control endpoint interrupt so that control requests can be handled
  96  *  asynchronously when they arrive rather than when the control endpoint is polled manually.
  97  */
  98 EVENT_HANDLER(USB_Reset)
  99 {
 100         /* Select the control endpoint */
 101         Endpoint_SelectEndpoint(ENDPOINT_CONTROLEP);
 102
 103         /* Enable the endpoint SETUP interrupt ISR for the control endpoint */
 104         USB_INT_Enable(ENDPOINT_INT_SETUP);
 105 }
 106
 107 /** Event handler for the USB_Connect event. This indicates that the device is enumerating via the status LEDs. */
 108 EVENT_HANDLER(USB_Connect)
 109 {
 110         /* Indicate USB enumerating */
 111         UpdateStatus(Status_USBEnumerating);
 112
 113         /* Reset the MSReset flag upon connection */
 114         IsMassStoreReset = false;
 115 }
 116
 117 /** Event handler for the USB_Disconnect event. This indicates that the device is no longer connected to a host via
 118  *  the status LEDs and stops the Mass Storage management task.
 119  */
 120 EVENT_HANDLER(USB_Disconnect)
 121 {
 122         /* Stop running mass storage task */
 123         Scheduler_SetTaskMode(USB_MassStorage, TASK_STOP);
 124
 125         /* Indicate USB not ready */
 126         UpdateStatus(Status_USBNotReady);
 127 }
 128
 129 /** Event handler for the USB_ConfigurationChanged event. This is fired when the host set the current configuration
 130  *  of the USB device after enumeration - the device endpoints are configured and the Mass Storage management task started.
 131  */
 132 EVENT_HANDLER(USB_ConfigurationChanged)
 133 {
 134         /* Setup Mass Storage In and Out Endpoints */
 135         Endpoint_ConfigureEndpoint(MASS_STORAGE_IN_EPNUM, EP_TYPE_BULK,
 136                                        ENDPOINT_DIR_IN, MASS_STORAGE_IO_EPSIZE,
 137                                    ENDPOINT_BANK_DOUBLE);
 138
 139         Endpoint_ConfigureEndpoint(MASS_STORAGE_OUT_EPNUM, EP_TYPE_BULK,
 140                                        ENDPOINT_DIR_OUT, MASS_STORAGE_IO_EPSIZE,
 141                                    ENDPOINT_BANK_DOUBLE);
 142
 143         /* Indicate USB connected and ready */
 144         UpdateStatus(Status_USBReady);
 145
 146         /* Start mass storage task */
 147         Scheduler_SetTaskMode(USB_MassStorage, TASK_RUN);
 148 }
 149
 150 /** Event handler for the USB_UnhandledControlPacket event. This is used to catch standard and class specific
 151  *  control requests that are not handled internally by the USB library (including the Mass Storage class-specific
 152  *  requests) so that they can be handled appropriately for the application.
 153  */
 154 EVENT_HANDLER(USB_UnhandledControlPacket)
 155 {
 156         /* Process UFI specific control requests */
 157         switch (bRequest)
 158         {
 159                 case REQ_MassStorageReset:
 160                         if (bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE))
 161                         {
 162                                 /* Indicate that the current transfer should be aborted */
 163                                 IsMassStoreReset = true;
 164
 165                                 Endpoint_ClearSetupReceived();
 166                                 Endpoint_ClearSetupIN();
 167                         }
 168
 169                         break;
 170                 case REQ_GetMaxLUN:
 171                         if (bmRequestType == (REQDIR_DEVICETOHOST | REQTYPE_CLASS | REQREC_INTERFACE))
 172                         {
 173                                 /* Indicate to the host the number of supported LUNs (virtual disks) on the device */
 174                                 Endpoint_ClearSetupReceived();
 175                                 Endpoint_Write_Byte(TOTAL_LUNS - 1);
 176                                 Endpoint_ClearSetupIN();
 177                         }
 178
 179                         break;
 180         }
 181 }
 182
 183 /** Function to manage status updates to the user. This is done via LEDs on the given board, if available, but may be changed to
 184  *  log to a serial port, or anything else that is suitable for status updates.
 185  *
 186  *  \param CurrentStatus  Current status of the system, from the MassStorage_StatusCodes_t enum
 187  */
 188 void UpdateStatus(uint8_t CurrentStatus)
 189 {
 190         uint8_t LEDMask = LEDS_NO_LEDS;
 191
 192         /* Set the LED mask to the appropriate LED mask based on the given status code */
 193         switch (CurrentStatus)
 194         {
 195                 case Status_USBNotReady:
 196                         LEDMask = (LEDS_LED1);
 197                         break;
 198                 case Status_USBEnumerating:
 199                         LEDMask = (LEDS_LED1 | LEDS_LED2);
 200                         break;
 201                 case Status_USBReady:
 202                         LEDMask = (LEDS_LED2 | LEDS_LED4);
 203                         break;
 204                 case Status_CommandBlockError:
 205                         LEDMask = (LEDS_LED1);
 206                         break;
 207                 case Status_ProcessingCommandBlock:
 208                         LEDMask = (LEDS_LED1 | LEDS_LED2);
 209                         break;
 210         }
 211
 212         /* Set the board LEDs to the new LED mask */
 213         LEDs_SetAllLEDs(LEDMask);
 214 }
 215
 216 /** Task to manage the Mass Storage interface, reading in Command Block Wrappers from the host, processing the SCSI commands they
 217  *  contain, and returning Command Status Wrappers back to the host to indicate the success or failure of the last issued command.
 218  */
 219 TASK(USB_MassStorage)
 220 {
 221         /* Check if the USB System is connected to a Host */
 222         if (USB_IsConnected)
 223         {
 224                 /* Select the Data Out Endpoint */
 225                 Endpoint_SelectEndpoint(MASS_STORAGE_OUT_EPNUM);
 226
 227                 /* Check to see if a command from the host has been issued */
 228                 if (Endpoint_ReadWriteAllowed())
 229                 {
 230                         /* Indicate busy */
 231                         UpdateStatus(Status_ProcessingCommandBlock);
 232
 233                         /* Process sent command block from the host */
 234                         if (ReadInCommandBlock())
 235                         {
 236                                 /* Check direction of command, select Data IN endpoint if data is from the device */
 237                                 if (CommandBlock.Flags & COMMAND_DIRECTION_DATA_IN)
 238                                   Endpoint_SelectEndpoint(MASS_STORAGE_IN_EPNUM);
 239
 240                                 /* Decode the received SCSI command */
 241                                 SCSI_DecodeSCSICommand();
 242
 243                                 /* Load in the CBW tag into the CSW to link them together */
 244                                 CommandStatus.Tag = CommandBlock.Tag;
 245
 246                                 /* Load in the data residue counter into the CSW */
 247                                 CommandStatus.DataTransferResidue = CommandBlock.DataTransferLength;
 248
 249                                 /* Stall the selected data pipe if command failed (if data is still to be transferred) */
 250                                 if ((CommandStatus.Status == Command_Fail) && (CommandStatus.DataTransferResidue))
 251                                   Endpoint_StallTransaction();
 252
 253                                 /* Return command status block to the host */
 254                                 ReturnCommandStatus();
 255
 256                                 /* Check if a Mass Storage Reset ocurred */
 257                                 if (IsMassStoreReset)
 258                                 {
 259                                         /* Reset the data endpoint banks */
 260                                         Endpoint_ResetFIFO(MASS_STORAGE_OUT_EPNUM);
 261                                         Endpoint_ResetFIFO(MASS_STORAGE_IN_EPNUM);
 262
 263                                         /* Clear the abort transfer flag */
 264                                         IsMassStoreReset = false;
 265                                 }
 266
 267                                 /* Indicate ready */
 268                                 UpdateStatus(Status_USBReady);
 269                         }
 270                         else
 271                         {
 272                                 /* Indicate error reading in the command block from the host */
 273                                 UpdateStatus(Status_CommandBlockError);
 274                         }
 275                 }
 276         }
 277 }
 278
 279 /** Function to read in a command block from the host, via the bulk data OUT endpoint. This function reads in the next command block
 280  *  if one has been issued, and performs validation to ensure that the block command is valid.
 281  *
 282  *  \return Boolean true if a valid command block has been read in from the endpoint, false otherwise
 283  */
 284 static bool ReadInCommandBlock(void)
 285 {
 286         /* Select the Data Out endpoint */
 287         Endpoint_SelectEndpoint(MASS_STORAGE_OUT_EPNUM);
 288
 289         /* Read in command block header */
 290         Endpoint_Read_Stream_LE(&CommandBlock, (sizeof(CommandBlock) - sizeof(CommandBlock.SCSICommandData)),
 291                                 AbortOnMassStoreReset);
 292
 293         /* Check if the current command is being aborted by the host */
 294         if (IsMassStoreReset)
 295           return false;
 296
 297         /* Verify the command block - abort if invalid */
 298         if ((CommandBlock.Signature != CBW_SIGNATURE) ||
 299             (CommandBlock.LUN >= TOTAL_LUNS) ||
 300                 (CommandBlock.SCSICommandLength > MAX_SCSI_COMMAND_LENGTH))
 301         {
 302                 /* Stall both data pipes until reset by host */
 303                 Endpoint_StallTransaction();
 304                 Endpoint_SelectEndpoint(MASS_STORAGE_IN_EPNUM);
 305                 Endpoint_StallTransaction();
 306
 307                 return false;
 308         }
 309
 310         /* Read in command block command data */
 311         Endpoint_Read_Stream_LE(&CommandBlock.SCSICommandData,
 312                                 CommandBlock.SCSICommandLength,
 313                                 AbortOnMassStoreReset);
 314
 315         /* Check if the current command is being aborted by the host */
 316         if (IsMassStoreReset)
 317           return false;
 318
 319         /* Finalize the stream transfer to send the last packet */
 320         Endpoint_ClearCurrentBank();
 321
 322         return true;
 323 }
 324
 325 /** Returns the filled Command Status Wrapper back to the host via the bulk data IN endpoint, waiting for the host to clear any
 326  *  stalled data endpoints as needed.
 327  */
 328 static void ReturnCommandStatus(void)
 329 {
 330         /* Select the Data Out endpoint */
 331         Endpoint_SelectEndpoint(MASS_STORAGE_OUT_EPNUM);
 332
 333         /* While data pipe is stalled, wait until the host issues a control request to clear the stall */
 334         while (Endpoint_IsStalled())
 335         {
 336                 /* Check if the current command is being aborted by the host */
 337                 if (IsMassStoreReset)
 338                   return;
 339         }
 340
 341         /* Select the Data In endpoint */
 342         Endpoint_SelectEndpoint(MASS_STORAGE_IN_EPNUM);
 343
 344         /* While data pipe is stalled, wait until the host issues a control request to clear the stall */
 345         while (Endpoint_IsStalled())
 346         {
 347                 /* Check if the current command is being aborted by the host */
 348                 if (IsMassStoreReset)
 349                   return;
 350         }
 351
 352         /* Write the CSW to the endpoint */
 353         Endpoint_Write_Stream_LE(&CommandStatus, sizeof(CommandStatus),
 354                                   AbortOnMassStoreReset);
 355
 356         /* Check if the current command is being aborted by the host */
 357         if (IsMassStoreReset)
 358           return;
 359
 360         /* Finalize the stream transfer to send the last packet */
 361         Endpoint_ClearCurrentBank();
 362 }
 363
 364 /** Stream callback function for the Endpoint stream read and write functions. This callback will abort the current stream transfer
 365  *  if a Mass Storage Reset request has been issued to the control endpoint.
 366  */
 367 STREAM_CALLBACK(AbortOnMassStoreReset)
 368 {
 369         /* Abort if a Mass Storage reset command was received */
 370         if (IsMassStoreReset)
 371           return STREAMCALLBACK_Abort;
 372
 373         /* Continue with the current stream operation */
 374         return STREAMCALLBACK_Continue;
 375 }
 376
 377 /** ISR for the general Pipe/Endpoint interrupt vector. This ISR fires when a control request has been issued to the control endpoint,
 378  *  so that the request can be processed. As several elements of the Mass Storage implementation require asynchronous control requests
 379  *  (such as endpoint stall clearing and Mass Storage Reset requests during data transfers) this is done via interrupts rather than
 380  *  polling.
 381  */
 382 ISR(ENDPOINT_PIPE_vect, ISR_BLOCK)
 383 {
 384         /* Check if the control endpoint has received a request */
 385         if (Endpoint_HasEndpointInterrupted(ENDPOINT_CONTROLEP))
 386         {
 387                 /* Clear the endpoint interrupt */
 388                 Endpoint_ClearEndpointInterrupt(ENDPOINT_CONTROLEP);
 389
 390                 /* Process the control request */
 391                 USB_USBTask();
 392
 393                 /* Handshake the endpoint setup interrupt - must be after the call to USB_USBTask() */
 394                 USB_INT_Clear(ENDPOINT_INT_SETUP);
 395         }
 396 }