tinyusb.git/examples/device/usbtest/skip.txt, branch master

dcd_lpc17_40: address review findings in the iso paths

2026-07-17T17:15:53Z

From a second max-effort review of the branch: - Drop the dead TUSB_XFER_ISOCHRONOUS case in dcd_edpt_open: iso endpoints are armed via dcd_edpt_iso_alloc/activate (TUP_DCD_EDPT_ISO_ALLOC is defined for this IP), never through dcd_edpt_open, so the case and its dd->isochronous assignment were unreachable and asserted a false invariant. Only bulk/interrupt reach the switch now. - Extend the iso compile gate to the classes that actually arm an iso endpoint: DCD_ISO_ENABLED now includes CFG_TUD_BTH (bth_device.c opens an iso voice endpoint). Without it a BTH build would compile the iso machinery out and fail SET_INTERFACE at runtime. - Un-skip LPC175X_6X in the usbtest example: it shares dcd_lpc17_40.c with LPC40XX verbatim, so the "DCD has no isochronous support" skip reason no longer holds. Build-verified for lpcxpresso1769 (previously blocked by the skip). - TU_ATTR_UNUSED on the ep_id_is_iso helper: every caller is under #if DCD_ISO_ENABLED, so non-iso builds don't reference it and clang's -Wunused-function (fatal in CI) rejected the build — gcc stays quiet. Verified with the full lpc17 and lpc40 example sets under arm-clang. A fifth finding — bounding control_ep_read's PACKET_READY spin with a timeout — was implemented and REVERTED: a naive 100k-iteration bound fires on legitimately-slow control reads and intermittently drops the device (hardware-proven by interleaved A/B testing against the pre-fix binary). The infinite wait is retained; the read is only reached once out_received/ out_queued signal data is present, so the theoretical IRQ-off hang is not reachable in practice. Re-verified on ea4088_quickstart: usbtest 30/30 (repeated) + HIL 14/14.

dcd_lpc17_40: fix stale EP0 out_received, add isochronous support

2026-07-17T09:48:01Z

EP0 control-OUT fix (usbtest 14/21, errno 110/-74): usbd queues the status-stage OUT ZLP of every control read with buffer=NULL, so the ISR's `if (out_buffer)` check missed it and marked the arriving ZLP as out_received instead. The stale flag poisoned the next control-OUT with data: its first chunk "completed" instantly from an empty EP0 buffer and the host's real DATA NAKed forever. Track queued transfers with an explicit out_queued flag and void half-finished control state on a new SETUP. Isochronous support (UM10562 12.15.6): 5-word DMA descriptors with per-packet size memory, buflen/present_count in packets, one packet per FRAME (no DMARSet/EpIntEn involvement), completion at EOT for both directions. Details that matter: - the iso machinery (5th DD word + packet-size memory) is compiled only when an iso-capable class is enabled (CFG_TUD_AUDIO/VIDEO/VENDOR), so non-iso builds pay nothing: _dcd stays 648 B vs 1032 B with iso - ISR dispatch keys on the hardware's fixed ep-number/type map (ep_id_is_iso), never on dd fields that thread mode rebuilds - iso OUT honors Packet_valid (bit 16) and prefills the hardware writeback slots with 0, so a missed frame counts as 0 bytes instead of reading back stale buffer contents as data - packet count is validated (tu_div_ceil <= ISO_MAX_PACKETS) before the DD is touched, so an oversized transfer is refused without leaving a serviceable half-built descriptor armed for the frame engine - dcd_edpt_iso_alloc and iso_activate both enforce the fixed iso endpoint numbers (3/6/9/12); classes ignore alloc's return value, so activate must not trust it Un-skip LPC40XX in the usbtest example; tier 4 now enumerates and passes iso cases 15/16/22/23. cdc_msc_throughput and printer_to_cdc had bulk on iso-only EP3 (SET_CONFIGURATION failed with -32); add the LPC17/40 EPNUM block (bulk on EP2/EP5) like other fixed-EP examples. Verified on ea4088_quickstart: usbtest tier-4 battery 30/30 repeatedly and the full device HIL suite 14/14 (incl. audio_test iso).

example(usbtest): device-side peer for the Linux kernel usbtest battery

2026-07-09T16:38:48Z

Gadget-Zero style source/sink on a vendor interface (alt0 empty, alt1 bulk+int+iso) plus EP0 ctrl_out; tier advertised in bcdDevice. Co-Authored-By: Claude Fable 5 Claude-Session: https://claude.ai/code/session_01HeF2gZ1M7GWkz6Av4BpKPg