Unit USBSTORAGE

Return to Unit Reference

Description

---

Ultibo USB Mass Storage Driver unit

USB Mass Storage Devices

The USB Mass Storage Class Control/Bulk/Interrupt (CBI) Transport specification is approved for use only with full-speed floppy disk drives. CBI shall not be used in high-speed capable devices, or in devices other than floppy disk drives. CBI shall not be used in devices that implement LSDFS. Usage of CBI for any new design is discouraged.

Therefore the majority of USB Mass Storage devices use the Bulk only interface.

USB mass storage class devices normally use the SCSI command set and therefore the USB storage driver consumes the SCSI unit for the protocol and command definitions. USB mass storage devices are registered directly as Storage devices not as SCSI devices.

Constants

---

[Expand]

USB storage USB_STORAGE_*

USBSTORAGE_STORAGE_DESCRIPTION = 'USB Storage Device';
USBSTORAGE_DRIVER_NAME = 'USB Mass Storage Driver';	Name of USB storage driver
CB/CBI (Control/Bulk/Interrupt) Requests
USB_STORAGE_REQUEST_CBI_ADSC = 0;
BBB (Bulk Only) Requests
USB_STORAGE_REQUEST_BBB_RESET = $FF;
USB_STORAGE_REQUEST_BBB_GET_MAX_LUN = $FE;
Command Block Wrapper
USB_STORAGE_CBW_SIGNATUR = $43425355;
USB_STORAGE_CBW_FLAGS_OUT = $00;
USB_STORAGE_CBW_FLAGS_IN = $80;
USB_STORAGE_CBW_CB_LENGTH = 16;
USB_STORAGE_CBW_SIZE = 31;
Command Status Wrapper
USB_STORAGE_CSW_SIGNATURE = $53425355;
USB_STORAGE_CSW_STATUS_GOOD = $00;
USB_STORAGE_CSW_STATUS_FAILED = $01;
USB_STORAGE_CSW_STATUS_PHASE = $02;
USB_STORAGE_CSW_SIZE = 13;
Command Data
USB_STORAGE_COMMAND_MAX_SIZE = 16;
Command Retry Counts
USB_STORAGE_READ_RETRIES = 2;
USB_STORAGE_WRITE_RETRIES = 2;
USB_STORAGE_STATUS_RETRIES = 2;
USB_STORAGE_INQUIRY_RETRIES = 5;
USB_STORAGE_READ_CAPACITY_RETRIES = 3;
USB_STORAGE_TEST_UNIT_READY_RETRIES = 5;	10; TestingRPi
Peripheral Device Types
These are a subset of the SCSI Peripheral Device Types
USB_STORAGE_DEVICE_TYPE_DISK = $00;	SBC Direct-access device (e.g., UHD Floppy disk)
USB_STORAGE_DEVICE_TYPE_CDROM = $05;	MMC-5 CD-ROM device
USB_STORAGE_DEVICE_TYPE_OPTICAL = $07;	Optical memory device (e.g., Non-CD optical disks)
USB_STORAGE_DEVICE_TYPE_RBC = $0E;	RBC Direct-access device (e.g., UHD Floppy disk)
USB_STORAGE_DEVICE_TYPE_UNKNOWN = $1F;	Unknown or no device type

Type definitions

---

USB command block

[Expand]

PUSBCommandBlock = ^TUSBCommandBlock;

TUSBCommandBlock = record

Note: SBC Command Block (Derived from TSCSICommandBlock)
SCSI Properties
Command:array[0..USB_STORAGE_COMMAND_MAX_SIZE - 1] of Byte;	Command
SenseData:array[0..63] of Byte;	Request Sense
Status:Byte;	SCSI Status
TargetID:Byte;	Target Id
TargetLUN:Byte;	Target LUN
CommandLength:Byte;	Command Length
DataLength:LongWord;	Data Length
Data:Pointer;	Pointer to Data
MessageOut:array[0..11] of Byte;	Message out buffer
MessageIn:array[0..11] of Byte;	Message in buffer
SenseCommandLength:Byte;	Sense Command Length
SenseDataLength:LongWord;	Sense Data Length
SenseCommand:array[0..5] of Byte;	Sense Command
ControllerStatus:LongWord;	Controller Status
TransferredBytes:LongWord;	Transferred Bytes
USB Properties
Direction:Byte;	USB Direction (eg USB_DIRECTION_OUT or USB_DIRECTION_IN)

USB storage device

[Expand]

PUSBStorageDevice = ^TUSBStorageDevice;

TUSBStorageDevice = record

Storage Properties
Storage:TStorageDevice;
USB Properties
Subclass:Byte;
Protocol:Byte;
MaxLUN:Byte;
Sequence:LongWord;	For dCBWTag property
Primary:PUSBStorageDevice;	Primary storage device (for multi LUN devices)
StorageInterface:PUSBInterface;	USB Mass Storage device Interface
ReadWait:TSemaphoreHandle;	Read completed semaphore
WriteWait:TSemaphoreHandle;	Write completed semaphore
InterruptWait:TSemaphoreHandle;	Interrupt completed semaphore
ReadRequest:PUSBRequest;	Bulk IN Request
WriteRequest:PUSBRequest;	Bulk OUT Request
InterruptRequest:PUSBRequest;	Interrupt IN Request
ReadEndpoint:PUSBEndpointDescriptor;	Bulk IN Endpoint
WriteEndpoint:PUSBEndpointDescriptor;	Bulk OUT Endpoint
InterruptEndpoint:PUSBEndpointDescriptor;	Interrupt IN Endpoint
PendingCount:LongWord;	Number of USB requests pending for this storage
WaiterThread:TThreadId;	Thread waiting for pending requests to complete (for storage eject)
SCSI Properties
CommandBlock:TUSBCommandBlock;
ATAPI Properties
RBC Properties

USB command block wrapper

[Expand]

PUSBCommandBlockWrapper = ^TUSBCommandBlockWrapper;

TUSBCommandBlockWrapper = record

dCBWSignature:LongWord;
dCBWTag:LongWord;
dCBWDataTransferLength:LongWord;
bCBWFlags:Byte;
bCBWLUN:Byte;
bCBWCBLength:Byte;
CBWCB:array[0..USB_STORAGE_CBW_CB_LENGTH - 1] of Byte;

USB command status wrapper

[Expand]

PUSBCommandStatusWrapper = ^TUSBCommandStatusWrapper;

TUSBCommandStatusWrapper = record

dCSWSignature:LongWord;
dCSWTag:LongWord;
dCSWDataResidue:LongWord;
bCSWStatus:Byte;

Function declarations

---

Initialization functions

[Expand]

procedure USBStorageInit;

Description: To be documented

Note	None documented

USB storage functions

[Expand]

function USBStorageDeviceRead(Storage:PStorageDevice; const Start,Count:Int64; Buffer:Pointer):LongWord;

Description: To be documented

Note	According to 3.4 of USB Mass Storage Bulk Only 1.0, requests must be queued one at a time to a device.

[Expand]

function USBStorageDeviceWrite(Storage:PStorageDevice; const Start,Count:Int64; Buffer:Pointer):LongWord;

Description: To be documented

Note	According to 3.4 of USB Mass Storage Bulk Only 1.0, requests must be queued one at a time to a device.

[Expand]

function USBStorageDeviceControl(Storage:PStorageDevice; Request:Integer; Argument1:PtrUInt; var Argument2:PtrUInt):LongWord;

Description: To be documented

Note	According to 3.4 of USB Mass Storage Bulk Only 1.0, requests must be queued one at a time to a device.

[Expand]

function USBStorageDriverBind(Device:PUSBDevice; Interrface:PUSBInterface):LongWord;

Description: Bind the Storage driver to a USB device if it is suitable

Device	The USB device to attempt to bind to
Interrface	The USB interface to attempt to bind to (or nil for whole device)
Return	USB_STATUS_SUCCESS if completed, USB_STATUS_DEVICE_UNSUPPORTED if unsupported or another error code on failure.

[Expand]

function USBStorageDriverUnbind(Device:PUSBDevice; Interrface:PUSBInterface):LongWord;

Description: Unbind the Storage driver from a USB device

Device	The USB device to unbind from
Interrface	The USB interface to unbind from (or nil for whole device)
Return	USB_STATUS_SUCCESS if completed or another error code on failure

[Expand]

procedure USBStorageReadComplete(Request:PUSBRequest);

Description: Called when a USB request from a USB storage bulk IN endpoint completes

Request	The USB request which has completed
Note	The thread that submitted the read request will hold the storage lock

[Expand]

procedure USBStorageWriteComplete(Request:PUSBRequest);

Description: Called when a USB request from a USB storage bulk OUT endpoint completes

Request	The USB request which has completed
Note	The thread that submitted the write request will hold the storage lock

[Expand]

procedure USBStorageInterruptComplete(Request:PUSBRequest);

Description: Called when a USB request from a USB storage IN interrupt endpoint completes

Request	The USB request which has completed
Note	The thread that submitted the interrupt request will hold the storage lock

USB storage helper functions

[Expand]

function USBStorageCheckDevice(Device:PUSBDevice):Boolean;

Description: Check if the supplied USB device is suitable for detection as a Mass Storage Device

Device	The USB device to check
Return	True if the device is suitable or False if it is not

[Expand]

function USBStorageCheckSubclass(Subclass:Byte):Boolean;

Description: To be documented

Note	None documented

[Expand]

function USBStorageCheckProtocol(Protocol:Byte):Boolean;

Description: To be documented

Note	None documented

[Expand]

function USBStorageBlockSizeToBlockShift(BlockSize:LongWord):LongWord;

Description: To be documented

Note	None documented

[Expand]

function USBStoragePatchDevice(Device:PUSBDevice; var Subclass,Protocol:Byte):LongWord;

Description: A function to adjust the subclass and protocol parameters of known defective devices

Note	None documented

[Expand]

function USBStorageFixupDevice(Device:PUSBDevice; var Vendor,Product:String):LongWord;

Description: A function to adjust the vendor and product parameters of known defective devices

Note	None documented

[Expand]

function USBStorageDeviceLock(Device:PUSBDevice; Storage:PUSBStorageDevice):LongWord;

Description: Issue a Prevent Media Removal request to a storage device

Note	None documented

[Expand]

function USBStorageDeviceUnlock(Device:PUSBDevice; Storage:PUSBStorageDevice):LongWord;

Description: Issue a Allow Media Removal request to a storage device

Note	None documented

[Expand]

function USBStorageDeviceLoad(Device:PUSBDevice; Storage:PUSBStorageDevice):LongWord;

Description: Issue a Start Stop request to a storage device

Note	None documented

[Expand]

function USBStorageDeviceEject(Device:PUSBDevice; Storage:PUSBStorageDevice):LongWord;

Description: Issue a Start Stop request to a storage device

Note	None documented

USB storage helper functions

[Expand]

function USBStorageDeviceReset(Device:PUSBDevice; Storage:PUSBStorageDevice):LongWord;

Description: Issue a Storage Reset request to a storage device

Note	Reset recovery (5.3.4 in USB Mass Storage Bulk Only 1.0) For Reset Recovery the host shall issue in the following order: a) a Bulk-Only Mass Storage Reset, b) a Clear Feature HALT to the Bulk-In endpoint, c) a Clear Feature HALT to the Bulk-Out endpoint. This is done in 3 steps. If the reset doesn't succeed, the device should be port reset.

[Expand]

function USBStorageDeviceGetInfo(Device:PUSBDevice; Storage:PUSBStorageDevice):LongWord;

Description: Obtain basic information about a storage device (Type, Size, State, Product etc)

Note	None documented

[Expand]

function USBStorageDeviceGetStatus(Device:PUSBDevice; Storage:PUSBStorageDevice):LongWord;

Description: Supported by Subclass SCSI/UFI/SFF8070

Note	None documented

[Expand]

function USBStorageDeviceGetMaxLUN(Device:PUSBDevice; Storage:PUSBStorageDevice; var MaxLUN:Byte):LongWord;

Description: Issue a Get Max LUN request to a storage device

Note	None documented

[Expand]

function USBStorageDeviceClearStall(Device:PUSBDevice; Storage:PUSBStorageDevice; Endpoint:PUSBEndpointDescriptor):LongWord;

Description: Issue a USB Clear Feature (HALT) to the supplied endpoint on a storage device

Note	None documented

[Expand]

function USBStorageDeviceInquiry(Device:PUSBDevice; Storage:PUSBStorageDevice; var DeviceType,DeviceFlags:LongWord; var Vendor,Product,Revision:PChar):LongWord;

Description: Issue a SCSI Inquiry command to a LUN on a storage device

Note	Supported by Subclass SCSI/UFI/SFF8070

[Expand]

function USBStorageDeviceRequestSense(Device:PUSBDevice; Storage:PUSBStorageDevice; var SenseKey,ASC,ASCQ:Byte):LongWord;

Description: Issue a SCSI Request Sense command to a LUN on a storage device

Note	Supported by Subclass SCSI/UFI/SFF8070

[Expand]

function USBStorageDeviceReadCapacity(Device:PUSBDevice; Storage:PUSBStorageDevice; var BlockSize,BlockShift:LongWord; var BlockCount:Int64):LongWord;

Description: Issue a SCSI Read Capacity command to a LUN on a storage device

Note	Supported by Subclass SCSI/UFI/SFF8070

[Expand]

function USBStorageDeviceTestUnitReady(Device:PUSBDevice; Storage:PUSBStorageDevice; var DeviceFlags:LongWord):LongWord;

Description: Issue a SCSI Test Unit Ready command to a LUN on a storage device

Note	Supported by Subclass SCSI/UFI/SFF8070

[Expand]

function USBStorageDeviceRead10(Device:PUSBDevice; Storage:PUSBStorageDevice; Start:LongWord; Count:Word;Buffer:Pointer):LongWord;

Description: Issue a SCSI Read10 command to a LUN on a storage device

Note	Supported by Subclass SCSI/UFI/SFF8070 Caller must hold the storage lock

[Expand]

function USBStorageDeviceWrite10(Device:PUSBDevice; Storage:PUSBStorageDevice; Start:LongWord;Count:Word; Buffer:Pointer):LongWord;

Description: Issue a SCSI Write10 command to a LUN on a storage device

Note	Supported by Subclass SCSI/UFI/SFF8070 Caller must hold the storage lock

[Expand]

function USBStorageDeviceRead16(Device:PUSBDevice; Storage:PUSBStorageDevice; const Start,Count:Int64; Buffer:Pointer):LongWord;

Description: Issue a SCSI Read16 command to a LUN on a storage device

Note	Supported by Subclass SCSI only (Only on devices > 2TB) Caller must hold the storage lock

[Expand]

function USBStorageDeviceWrite16(Device:PUSBDevice; Storage:PUSBStorageDevice; const Start,Count:Int64; Buffer:Pointer):LongWord;

Description: Issue a SCSI Write16 command to a LUN on a storage device

Note	Supported by Subclass SCSI only (Only on devices > 2TB) Caller must hold the storage lock

[Expand]

function USBStorageDeviceTransport(Device:PUSBDevice; Storage:PUSBStorageDevice; Command:PUSBCommandBlock):LongWord;

Description: Perform the appropriate transport sequence for the device based on subclass and protocol

Note	Handles Command / Data / Status phases plus endpoint stall, reset and retry as per the specification. Supported by Subclass SCSI/UFI/SFF8070 Caller must hold the storage lock

Return to Unit Reference