2026-09-23, S3 Touch on 61ba01c hosting the P4 wearing cdc+uac. A probe started the host with classes=("uac",), listed uac_audio.audio_devices() (one device, one stream, never opened) and called stop():
usbif_host: teardown starting (new devices now declined)
usbif_host: closing cdc / hid / midi / msc / uac
usbif_host: device_close
usbif_host: device_close returned
usbif_host: pre-deregister drain done
usbif_host: deregister -> 0x0
usbif_host: device_free_all -> 0x10c
usbif_host_stop: task DID NOT EXIT -- timed out (marked wedged) after 200 tick(s) (2000 ms)
usbif_host_stop: calling usb_phy_otg_device_mode()
usbif_host_stop: calling tusb_init()
The next host.start() in the same session then fails with OSError: [Errno 5] EIO; a hard reset clears it. device_free_all -> 0x10c is ESP_ERR_NOT_FINISHED: the library still held the device when we asked it to free everything, so the host task never reached its exit. The README's 8-of-8 clean stops were measured with devices that had been opened and closed through a class driver; this is the other path, a device that was only enumerated.
2026-09-23, S3 Touch on 61ba01c hosting the P4 wearing cdc+uac. A probe started the host with
classes=("uac",), listeduac_audio.audio_devices()(one device, one stream, never opened) and calledstop():The next
host.start()in the same session then fails withOSError: [Errno 5] EIO; a hard reset clears it.device_free_all -> 0x10cis ESP_ERR_NOT_FINISHED: the library still held the device when we asked it to free everything, so the host task never reached its exit. The README's 8-of-8 clean stops were measured with devices that had been opened and closed through a class driver; this is the other path, a device that was only enumerated.