When NRF5x device is reset by software (after DFU for example),
power event is ready from the beginning.
When power interrupt is triggered before tud_init() finished
USBD_IRQn is enabled before it would be enabled in tud_init().
This in turn may result in BUS RESET event being sent from
USB interrupt to USB task when queue is not initialized yet.
This scenario often happens in Mynewt build where queue creation
takes more time.
To prevent this scenario USBD_IRQn is not enabled in power event
interrupt handler before dcd_init() was called.
The datasheet says 2KB FIFO, but accroding to many
code examples, the F1C100s has at least 4KB of FIFO memory.
This is working with cdc_msc example,
but I'm not sure, this should be checked.
Allwinner F1Cx00s family is a series of SoCs
with Mentor MUSB controller and HS phy. It comes
with a slightly different register space layout,
and some quirks, so it's not multiplexed with
the existing musb support library.
This library currently requires to be compiled
with https://github.com/hongxuyao/F1C100s_with_Keil_RTX4_emWin5
Bluetooth's specification defines IAD for primary controller.
While it seems that Windows and Linux can leave without this,
there is no reason TinyUSB should not provide it.
Two interfaces that are required by Bluetooth Primary Controller
do not have IAD according to Bluetooth specification.
Those two interfaces were opened separately in process_set_config().
Later interface association was inferred for BTH (along with other
drivers), since then only one call to open() is place for BTH driver
that should prepare both interfaces at once.
To make it work again btd_open() parses two interfaces at once.
Jerzy Kasenberg