esp_tinyusb port ECM/RNDIS supprt (IEC-176) (IEC-178)

[chegewara]

Answers checklist.

• I have read the documentation of the component in question and the issue is not addressed there.
• I have searched the issue tracker for a similar issue and not found a similar issue.

General issue report

Hi,
quick test with USB-NCM shows it is working, but there is problem with ECM/RNDIS. (v1.4.5)
According to changelog ECM/RNDIS support should be added:

## 1.1.0

- Added support for NCM, ECM/RNDIS, DFU and Bluetooth TinyUSB drivers https://github.com/espressif/idf-extra-components/commit/79f35c9b047b583080f93a63310e2ee7d82ef17b

but only NCM is enabled in CMakeLists

if(CONFIG_TINYUSB_NET_MODE_NCM)
    list(APPEND srcs
         tinyusb_net.c
         )
endif() # CONFIG_TINYUSB_NET_MODE_NCM

When trying to build with ECM enabled in menuconfig i get many (10) undefined reference to errors.

Thanks

BTW NCM is using different callback than ECM, so the init_cb callback on NCM is not working (no big issue)

tud_network_link_state_cb <--- NCM
tud_network_init_cb <--- ECM/RNDIS

[tore-espressif]

@chegewara Thank you very much for trying this out.

The engineer who mainly worked on this left some work unfinished, ie here we wanted to remove support for ECM/RNDIS because it was never implemented in esp_tinyusb in a first place espressif/idf-extra-components#235

ATM, we want to upgrade to TinyUSB v0.17 which contains refactored NCM driver, if it works OK, we don't plan to implement ECM/RNDIS mainly because of maintenance cost

[chegewara]

That's sad there is no plan to add ECM, because NCM is not supported on android.

I hope espressif don't plan to remove current ECM code, so maybe community will expand it (maybe I will try to work on it, if it's not a problem).

Thanks for good work on USB

Btw I think RNDIS is supported in tinyusb