Enum TransferError 

pub enum TransferError {
    Stall,
    TransactionError,
    Babble,
    Nak,
    NakTimeout,
    FrameOverrun,
    DataToggleError,
    Halted,
    Timeout,
}

Available on non-crate feature bcm2712 only.

Why a single-packet channel transfer didn’t complete successfully.

Variants

Stall

The device returned STALL — it doesn’t support/recognize the request.

TransactionError

HCINT.TXERR — a transaction error (no response, bad CRC, etc.).

Babble

HCINT.BBERR — babble (the device sent more than expected).

Nak

The device NAK’d this attempt — normal USB flow control (“not ready yet, ask again”), not a real error. Left for the caller to retry; see crate::usb::control’s retry wrapper.

NakTimeout

A caller-level retry budget was exhausted while the device kept NAKing — distinct from a single Self::Nak.

FrameOverrun

HCINT.FRMOR — frame overrun. A periodic (interrupt or isochronous) transaction was still in progress when the microframe it was scheduled in ran out, and the core abandoned it.

This is about when the transaction was started, not about the device: a periodic transfer armed late in a microframe has too little of it left to finish. Retrying on the next interval is the normal response, which is why callers should treat this much as they treat Self::Nak rather than as a hard failure.

DataToggleError

HCINT.DTERR — the packet arrived carrying the opposite data toggle to the one expected, so it was discarded as a retransmission of one already received. Means host and device have lost toggle synchronisation.

Halted

The channel halted (HCINT.CHH) without HCINT.XFRC (transfer complete) and without any specific error/status bit set — an unexplained halt. Not expected in normal operation now that completion is detected via CHH; a defensive branch rather than a condition seen in practice.

Timeout

The channel never halted (HCINT.CHH never set) within this driver’s timeout — the transaction appears stuck rather than having reached any terminal condition.

Trait Implementations

impl Clone for TransferError

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for TransferError

impl Debug for TransferError

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for TransferError

impl From<TransferError> for EnumerationError

fn from(error: TransferError) -> Self

Converts to this type from the input type.

impl PartialEq for TransferError

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for TransferError