Demos/Device/ClassDriver/MassStorage/Lib/SCSI.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  *  SCSI command processing routines, for SCSI commands issued by the host. Mass Storage
  34  *  devices use a thin "Bulk-Only Transport" protocol for issuing commands and status information,
  35  *  which wrap around standard SCSI device commands for controlling the actual storage medium.
  36  */
  37
  38 #define  INCLUDE_FROM_SCSI_C
  39 #include "SCSI.h"
  40
  41 /** Structure to hold the SCSI response data to a SCSI INQUIRY command. This gives information about the device's
  42  *  features and capabilities.
  43  */
  44 SCSI_Inquiry_Response_t InquiryData =
  45         {
  46                 .DeviceType          = DEVICE_TYPE_BLOCK,
  47                 .PeripheralQualifier = 0,
  48
  49                 .Removable           = true,
  50
  51                 .Version             = 0,
  52
  53                 .ResponseDataFormat  = 2,
  54                 .NormACA             = false,
  55                 .TrmTsk              = false,
  56                 .AERC                = false,
  57
  58                 .AdditionalLength    = 0x1F,
  59
  60                 .SoftReset           = false,
  61                 .CmdQue              = false,
  62                 .Linked              = false,
  63                 .Sync                = false,
  64                 .WideBus16Bit        = false,
  65                 .WideBus32Bit        = false,
  66                 .RelAddr             = false,
  67
  68                 .VendorID            = "LUFA",
  69                 .ProductID           = "Dataflash Disk",
  70                 .RevisionID          = {'0','.','0','0'},
  71         };
  72
  73 /** Structure to hold the sense data for the last issued SCSI command, which is returned to the host after a SCSI REQUEST SENSE
  74  *  command is issued. This gives information on exactly why the last command failed to complete.
  75  */
  76 SCSI_Request_Sense_Response_t SenseData =
  77         {
  78                 .ResponseCode        = 0x70,
  79                 .AdditionalLength    = 0x0A,
  80         };
  81
  82
  83 /** Main routine to process the SCSI command located in the Command Block Wrapper read from the host. This dispatches
  84  *  to the appropriate SCSI command handling routine if the issued command is supported by the device, else it returns
  85  *  a command failure due to a ILLEGAL REQUEST.
  86  *
  87  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
  88  */
  89 bool SCSI_DecodeSCSICommand(USB_ClassInfo_MS_Device_t* MSInterfaceInfo)
  90 {
  91         bool CommandSuccess = false;
  92
  93         /* Run the appropriate SCSI command hander function based on the passed command */
  94         switch (MSInterfaceInfo->State.CommandBlock.SCSICommandData[0])
  95         {
  96                 case SCSI_CMD_INQUIRY:
  97                         CommandSuccess = SCSI_Command_Inquiry(MSInterfaceInfo);
  98                         break;
  99                 case SCSI_CMD_REQUEST_SENSE:
 100                         CommandSuccess = SCSI_Command_Request_Sense(MSInterfaceInfo);
 101                         break;
 102                 case SCSI_CMD_READ_CAPACITY_10:
 103                         CommandSuccess = SCSI_Command_Read_Capacity_10(MSInterfaceInfo);
 104                         break;
 105                 case SCSI_CMD_SEND_DIAGNOSTIC:
 106                         CommandSuccess = SCSI_Command_Send_Diagnostic(MSInterfaceInfo);
 107                         break;
 108                 case SCSI_CMD_WRITE_10:
 109                         CommandSuccess = SCSI_Command_ReadWrite_10(MSInterfaceInfo, DATA_WRITE);
 110                         break;
 111                 case SCSI_CMD_READ_10:
 112                         CommandSuccess = SCSI_Command_ReadWrite_10(MSInterfaceInfo, DATA_READ);
 113                         break;
 114                 case SCSI_CMD_TEST_UNIT_READY:
 115                 case SCSI_CMD_PREVENT_ALLOW_MEDIUM_REMOVAL:
 116                 case SCSI_CMD_VERIFY_10:
 117                         /* These commands should just succeed, no handling required */
 118                         CommandSuccess = true;
 119                         MSInterfaceInfo->State.CommandBlock.DataTransferLength = 0;
 120                         break;
 121                 default:
 122                         /* Update the SENSE key to reflect the invalid command */
 123                         SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
 124                                    SCSI_ASENSE_INVALID_COMMAND,
 125                                    SCSI_ASENSEQ_NO_QUALIFIER);
 126                         break;
 127         }
 128
 129         /* Check if command was successfully processed */
 130         if (CommandSuccess)
 131         {
 132                 SCSI_SET_SENSE(SCSI_SENSE_KEY_GOOD,
 133                                SCSI_ASENSE_NO_ADDITIONAL_INFORMATION,
 134                                SCSI_ASENSEQ_NO_QUALIFIER);
 135
 136                 return true;
 137         }
 138
 139         return false;
 140 }
 141
 142 /** Command processing for an issued SCSI INQUIRY command. This command returns information about the device's features
 143  *  and capabilities to the host.
 144  *
 145  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 146  *
 147  *  \return Boolean true if the command completed successfully, false otherwise.
 148  */
 149 static bool SCSI_Command_Inquiry(USB_ClassInfo_MS_Device_t* MSInterfaceInfo)
 150 {
 151         uint16_t AllocationLength  = (((uint16_t)MSInterfaceInfo->State.CommandBlock.SCSICommandData[3] << 8) |
 152                                                  MSInterfaceInfo->State.CommandBlock.SCSICommandData[4]);
 153         uint16_t BytesTransferred  = (AllocationLength < sizeof(InquiryData))? AllocationLength :
 154                                                                                sizeof(InquiryData);
 155
 156         /* Only the standard INQUIRY data is supported, check if any optional INQUIRY bits set */
 157         if ((MSInterfaceInfo->State.CommandBlock.SCSICommandData[1] & ((1 << 0) | (1 << 1))) ||
 158              MSInterfaceInfo->State.CommandBlock.SCSICommandData[2])
 159         {
 160                 /* Optional but unsupported bits set - update the SENSE key and fail the request */
 161                 SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
 162                                SCSI_ASENSE_INVALID_FIELD_IN_CDB,
 163                                SCSI_ASENSEQ_NO_QUALIFIER);
 164
 165                 return false;
 166         }
 167
 168         Endpoint_Write_Stream_LE(&InquiryData, BytesTransferred, NO_STREAM_CALLBACK);
 169
 170         uint8_t PadBytes[AllocationLength - BytesTransferred];
 171
 172         /* Pad out remaining bytes with 0x00 */
 173         Endpoint_Write_Stream_LE(&PadBytes, (AllocationLength - BytesTransferred), NO_STREAM_CALLBACK);
 174
 175         /* Finalize the stream transfer to send the last packet */
 176         Endpoint_ClearIN();
 177
 178         /* Succeed the command and update the bytes transferred counter */
 179         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= BytesTransferred;
 180
 181         return true;
 182 }
 183
 184 /** Command processing for an issued SCSI REQUEST SENSE command. This command returns information about the last issued command,
 185  *  including the error code and additional error information so that the host can determine why a command failed to complete.
 186  *
 187  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 188  *
 189  *  \return Boolean true if the command completed successfully, false otherwise.
 190  */
 191 static bool SCSI_Command_Request_Sense(USB_ClassInfo_MS_Device_t* MSInterfaceInfo)
 192 {
 193         uint8_t  AllocationLength = MSInterfaceInfo->State.CommandBlock.SCSICommandData[4];
 194         uint8_t  BytesTransferred = (AllocationLength < sizeof(SenseData))? AllocationLength : sizeof(SenseData);
 195
 196         uint8_t PadBytes[AllocationLength - BytesTransferred];
 197
 198         Endpoint_Write_Stream_LE(&SenseData, BytesTransferred, NO_STREAM_CALLBACK);
 199         Endpoint_Write_Stream_LE(&PadBytes, (AllocationLength - BytesTransferred), NO_STREAM_CALLBACK);
 200         Endpoint_ClearIN();
 201
 202         /* Succeed the command and update the bytes transferred counter */
 203         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= BytesTransferred;
 204
 205         return true;
 206 }
 207
 208 /** Command processing for an issued SCSI READ CAPACITY (10) command. This command returns information about the device's capacity
 209  *  on the selected Logical Unit (drive), as a number of OS-sized blocks.
 210  *
 211  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 212  *
 213  *  \return Boolean true if the command completed successfully, false otherwise.
 214  */
 215 static bool SCSI_Command_Read_Capacity_10(USB_ClassInfo_MS_Device_t* MSInterfaceInfo)
 216 {
 217         uint32_t LastBlockAddressInLUN = (LUN_MEDIA_BLOCKS - 1);
 218         uint32_t MediaBlockSize        = VIRTUAL_MEMORY_BLOCK_SIZE;
 219
 220         Endpoint_Write_Stream_BE(&LastBlockAddressInLUN, sizeof(LastBlockAddressInLUN), NO_STREAM_CALLBACK);
 221         Endpoint_Write_Stream_BE(&MediaBlockSize, sizeof(MediaBlockSize), NO_STREAM_CALLBACK);
 222         Endpoint_ClearIN();
 223
 224         /* Succeed the command and update the bytes transferred counter */
 225         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= 8;
 226
 227         return true;
 228 }
 229
 230 /** Command processing for an issued SCSI SEND DIAGNOSTIC command. This command performs a quick check of the Dataflash ICs on the
 231  *  board, and indicates if they are present and functioning correctly. Only the Self-Test portion of the diagnostic command is
 232  *  supported.
 233  *
 234  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 235  *
 236  *  \return Boolean true if the command completed successfully, false otherwise.
 237  */
 238 static bool SCSI_Command_Send_Diagnostic(USB_ClassInfo_MS_Device_t* MSInterfaceInfo)
 239 {
 240         /* Check to see if the SELF TEST bit is not set */
 241         if (!(MSInterfaceInfo->State.CommandBlock.SCSICommandData[1] & (1 << 2)))
 242         {
 243                 /* Only self-test supported - update SENSE key and fail the command */
 244                 SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
 245                                SCSI_ASENSE_INVALID_FIELD_IN_CDB,
 246                                SCSI_ASENSEQ_NO_QUALIFIER);
 247
 248                 return false;
 249         }
 250
 251         /* Check to see if all attached Dataflash ICs are functional */
 252         if (!(DataflashManager_CheckDataflashOperation()))
 253         {
 254                 /* Update SENSE key with a hardware error condition and return command fail */
 255                 SCSI_SET_SENSE(SCSI_SENSE_KEY_HARDWARE_ERROR,
 256                                SCSI_ASENSE_NO_ADDITIONAL_INFORMATION,
 257                                SCSI_ASENSEQ_NO_QUALIFIER);
 258
 259                 return false;
 260         }
 261
 262         /* Succeed the command and update the bytes transferred counter */
 263         MSInterfaceInfo->State.CommandBlock.DataTransferLength = 0;
 264
 265         return true;
 266 }
 267
 268 /** Command processing for an issued SCSI READ (10) or WRITE (10) command. This command reads in the block start address
 269  *  and total number of blocks to process, then calls the appropriate low-level dataflash routine to handle the actual
 270  *  reading and writing of the data.
 271  *
 272  *  \param[in] MSInterfaceInfo  Pointer to the Mass Storage class interface structure that the command is associated with
 273  *  \param[in] IsDataRead  Indicates if the command is a READ (10) command or WRITE (10) command (DATA_READ or DATA_WRITE)
 274  *
 275  *  \return Boolean true if the command completed successfully, false otherwise.
 276  */
 277 static bool SCSI_Command_ReadWrite_10(USB_ClassInfo_MS_Device_t* MSInterfaceInfo, const bool IsDataRead)
 278 {
 279         uint32_t BlockAddress;
 280         uint16_t TotalBlocks;
 281
 282         /* Load in the 32-bit block address (SCSI uses big-endian, so have to do it byte-by-byte) */
 283         ((uint8_t*)&BlockAddress)[3] = MSInterfaceInfo->State.CommandBlock.SCSICommandData[2];
 284         ((uint8_t*)&BlockAddress)[2] = MSInterfaceInfo->State.CommandBlock.SCSICommandData[3];
 285         ((uint8_t*)&BlockAddress)[1] = MSInterfaceInfo->State.CommandBlock.SCSICommandData[4];
 286         ((uint8_t*)&BlockAddress)[0] = MSInterfaceInfo->State.CommandBlock.SCSICommandData[5];
 287
 288         /* Load in the 16-bit total blocks (SCSI uses big-endian, so have to do it byte-by-byte) */
 289         ((uint8_t*)&TotalBlocks)[1]  = MSInterfaceInfo->State.CommandBlock.SCSICommandData[7];
 290         ((uint8_t*)&TotalBlocks)[0]  = MSInterfaceInfo->State.CommandBlock.SCSICommandData[8];
 291
 292         /* Check if the block address is outside the maximum allowable value for the LUN */
 293         if (BlockAddress >= LUN_MEDIA_BLOCKS)
 294         {
 295                 /* Block address is invalid, update SENSE key and return command fail */
 296                 SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
 297                                SCSI_ASENSE_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE,
 298                                SCSI_ASENSEQ_NO_QUALIFIER);
 299
 300                 return false;
 301         }
 302
 303         #if (TOTAL_LUNS > 1)
 304         /* Adjust the given block address to the real media address based on the selected LUN */
 305         BlockAddress += ((uint32_t)MSInterfaceInfo->State.CommandBlock.LUN * LUN_MEDIA_BLOCKS);
 306         #endif
 307
 308         /* Determine if the packet is a READ (10) or WRITE (10) command, call appropriate function */
 309         if (IsDataRead == DATA_READ)
 310           DataflashManager_ReadBlocks(MSInterfaceInfo, BlockAddress, TotalBlocks);
 311         else
 312           DataflashManager_WriteBlocks(MSInterfaceInfo, BlockAddress, TotalBlocks);
 313
 314         /* Update the bytes transferred counter and succeed the command */
 315         MSInterfaceInfo->State.CommandBlock.DataTransferLength -= ((uint32_t)TotalBlocks * VIRTUAL_MEMORY_BLOCK_SIZE);
 316
 317         return true;
 318 }