An XFER_COMPLETE dropped by a full event queue leaves its endpoint's
BUSY|CLAIMED state set forever - the consumer that normally clears it
never sees the event, so usbd_edpt_claim()/usbd_edpt_xfer() fail from
then on and the class never re-arms the endpoint. Clear both flags when
the enqueue fails: the completion is lost either way, but the endpoint
stays usable.
Unit test: arm a bulk endpoint, drop its completion against a full
queue, verify the endpoint can be claimed and re-armed.
A SETUP arriving while the event queue is full is silently dropped by
queue_event(), but _usbd_queued_setup has already been incremented. The
leaked count makes the event handler skip every subsequent SETUP
("Skipped since there is other SETUP in queue") forever: EP0 stays deaf
until tud_init() while the device otherwise looks alive - enumerated,
endpoints armed. Undo the increment when the enqueue fails.
Unit test: fill the queue so a SETUP is dropped, then verify the next
SETUP still completes a GET_DESCRIPTOR control transfer.
* device: clamp EP0 OUT data copy to the control transfer buffer
usbd_control_xfer_cb() copied xferred_bytes from the EP0 bounce buffer
into the requester's buffer with no bound. A non-compliant host that
sends an OUT data packet larger than the control transfer's data_len
(= min(len, wLength), the buffer capacity) would overflow that buffer
and over-count total_xferred. Clamp xferred_bytes to the remaining
buffer space before the memcpy and accounting.
Brings the MIDI 2.0 device driver into full conformance with USB
Device Class Definition for MIDI Devices v2.0 (USB-IF, May 2020).
- Alt 1 MS Interface Header wTotalLength now reports 0x0007 per
Table 5-2 ("set to match bLength"), replacing the prior 0x0011
carried over from USB-MIDI 1.0 conventions.
- GET_DESCRIPTOR class request now validates bmRequestType direction,
type and recipient plus wIndex and wValue high byte per Section 6.
- iBlockItem in the default Group Terminal Block is driven by
CFG_TUD_MIDI2_BLOCK_STRIDX so applications can attach a UI string
descriptor to the block per Table 5-6.
- UMP word byte order assumption (little-endian host per Section
3.2.2) is documented inline so future big-endian ports know where
to wrap access with tu_htole32 / tu_le32toh.
Validated on RP2040 and ESP32-P4 under Linux kernel 6.17: lsusb -v
reports wTotalLength = 0x0007 on Alt 1 MS Header (raw bytes
07 24 01 00 02 07 00). amidi -l enumerates Group Terminals exposed
via the class-specific GET_DESCRIPTOR response.
