//! This function transfers the data between memory and USB MSC interface
//!
//! @param addr Sector address to start read
//! @param nb_sector Number of sectors to transfer (sector=512 bytes)
//! @param b_read Memory to USB, if true
//!
//! @return Ctrl_status
//! It is ready -> CTRL_GOOD
//! Memory unplug -> CTRL_NO_PRESENT
//! Not initialized or changed -> CTRL_BUSY
//! An error occurred -> CTRL_FAIL
//!
static Ctrl_status virtual_usb_trans(uint32_t addr, uint16_t nb_sector, bool b_read)
{
if ((addr > VMEM_NB_SECTOR) || (addr + nb_sector > VMEM_NB_SECTOR)) {
return CTRL_FAIL;
}
for (uint16_t i = 0; i < nb_sector; i++)
{
if (b_read) {
VirtualFAT_ReadBlock(addr + i);
if (!udi_msc_trans_block(b_read, BlockBuffer, VMEM_SECTOR_SIZE, NULL)) {
return CTRL_FAIL; // transfer aborted
}
} else {
if (!udi_msc_trans_block(b_read, BlockBuffer, VMEM_SECTOR_SIZE, NULL)) {
return CTRL_FAIL; // transfer aborted
}
VirtualFAT_WriteBlock(addr + i);
}
}
return CTRL_GOOD;
}
/** Command processing for an issued SCSI READ (10) or WRITE (10) command. This command reads in the block start address
* and total number of blocks to process, then calls the appropriate low-level Dataflash routine to handle the actual
* reading and writing of the data.
*
* \param[in] MSInterfaceInfo Pointer to the Mass Storage class interface structure that the command is associated with
* \param[in] IsDataRead Indicates if the command is a READ (10) command or WRITE (10) command (DATA_READ or DATA_WRITE)
*
* \return Boolean \c true if the command completed successfully, \c false otherwise.
*/
static bool SCSI_Command_ReadWrite_10(USB_ClassInfo_MS_Device_t* const MSInterfaceInfo,
const bool IsDataRead)
{
uint16_t BlockAddress;
uint16_t TotalBlocks;
/* Load in the 32-bit block address (SCSI uses big-endian, so have to reverse the byte order) */
BlockAddress = SwapEndian_32(*(uint32_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[2]);
/* Load in the 16-bit total blocks (SCSI uses big-endian, so have to reverse the byte order) */
TotalBlocks = SwapEndian_16(*(uint16_t*)&MSInterfaceInfo->State.CommandBlock.SCSICommandData[7]);
/* Check if the block address is outside the maximum allowable value for the LUN */
if (BlockAddress >= LUN_MEDIA_BLOCKS)
{
/* Block address is invalid, update SENSE key and return command fail */
SCSI_SET_SENSE(SCSI_SENSE_KEY_ILLEGAL_REQUEST,
SCSI_ASENSE_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE,
SCSI_ASENSEQ_NO_QUALIFIER);
return false;
}
/* Determine if the packet is a READ (10) or WRITE (10) command, call appropriate function */
for (uint16_t i = 0; i < TotalBlocks; i++)
{
if (IsDataRead == DATA_READ)
VirtualFAT_ReadBlock(BlockAddress + i);
else
VirtualFAT_WriteBlock(BlockAddress + i);
}
/* Update the bytes transferred counter and succeed the command */
MSInterfaceInfo->State.CommandBlock.DataTransferLength -= ((uint32_t)TotalBlocks * SECTOR_SIZE_BYTES);
return true;
}