Texas Instruments OMAP5912 Reference Manual page 1446

USB Device Controller
3.15 Endpoint 0 TX Interrupt Handler
154 Universal Serial Bus (USB)
Figure 20 shows the TX portion of the general USB interrupt handler, which
must handle general USB interrupts related to control IN transactions on
endpoint 0.
The endpoint 0 TX interrupt handler must be able to move data into the
endpoint 0 TX FIFO when the application buffer for endpoint 0 TX data is not
empty and an endpoint 0 TX interrupt occurs signaling an ACKed
non-autodecoded endpoint 0 IN transaction. This data can be control read
data stage information or control write status stage handshaking information
(see Figure 21).
SPRU761A