USB to Ethernet adapter

[gadget-man]

As an alternative to WiFi, I'd like to be able to connect my ESP32S3 to the network using a usb-ethernet dongle. It uses a Realtek 8152 chipset which I understand is CDC-NCM compatible. Here is the configuration descriptor:

2025-02-17 15:23:43 bLength 9
2025-02-17 15:23:43 bDescriptorType 2
2025-02-17 15:23:43 wTotalLength 80
2025-02-17 15:23:43 bNumInterfaces 2
2025-02-17 15:23:43 bConfigurationValue 2
2025-02-17 15:23:43 iConfiguration 0
2025-02-17 15:23:43 bmAttributes 0xa0
2025-02-17 15:23:43 bMaxPower 100mA
2025-02-17 15:23:43     *** Interface descriptor ***
2025-02-17 15:23:43     bLength 9
2025-02-17 15:23:43     bDescriptorType 4
2025-02-17 15:23:43     bInterfaceNumber 0
2025-02-17 15:23:43     bAlternateSetting 0
2025-02-17 15:23:43     bNumEndpoints 1
2025-02-17 15:23:43     bInterfaceClass 0x2
2025-02-17 15:23:43     bInterfaceSubClass 0x6
2025-02-17 15:23:43     bInterfaceProtocol 0x0
2025-02-17 15:23:43     iInterface 5
2025-02-17 15:23:43             *** Endpoint descriptor ***
2025-02-17 15:23:43             bLength 7
2025-02-17 15:23:43             bDescriptorType 5
2025-02-17 15:23:43             bEndpointAddress 0x83   EP 3 IN
2025-02-17 15:23:43             bmAttributes 0x3        INT
2025-02-17 15:23:43             wMaxPacketSize 16
2025-02-17 15:23:43             bInterval 8
2025-02-17 15:23:43     *** Interface descriptor ***
2025-02-17 15:23:43     bLength 9
2025-02-17 15:23:43     bDescriptorType 4
2025-02-17 15:23:43     bInterfaceNumber 1
2025-02-17 15:23:43     bAlternateSetting 0
2025-02-17 15:23:43     bNumEndpoints 0
2025-02-17 15:23:43     bInterfaceClass 0xa
2025-02-17 15:23:43     bInterfaceSubClass 0x0
2025-02-17 15:23:43     bInterfaceProtocol 0x0
2025-02-17 15:23:43     iInterface 0
2025-02-17 15:23:43     *** Interface descriptor ***
2025-02-17 15:23:43     bLength 9
2025-02-17 15:23:43     bDescriptorType 4
2025-02-17 15:23:43     bInterfaceNumber 1
2025-02-17 15:23:43     bAlternateSetting 1
2025-02-17 15:23:43     bNumEndpoints 2
2025-02-17 15:23:43     bInterfaceClass 0xa
2025-02-17 15:23:43     bInterfaceSubClass 0x0
2025-02-17 15:23:43     bInterfaceProtocol 0x0
2025-02-17 15:23:43     iInterface 4
2025-02-17 15:23:43             *** Endpoint descriptor ***
2025-02-17 15:23:43             bLength 7
2025-02-17 15:23:43             bDescriptorType 5
2025-02-17 15:23:43             bEndpointAddress 0x81   EP 1 IN
2025-02-17 15:23:43             bmAttributes 0x2        BULK
2025-02-17 15:23:43             wMaxPacketSize 64
2025-02-17 15:23:43             bInterval 0
2025-02-17 15:23:43             *** Endpoint descriptor ***
2025-02-17 15:23:43             bLength 7
2025-02-17 15:23:43             bDescriptorType 5
2025-02-17 15:23:43             bEndpointAddress 0x2    EP 2 OUT
2025-02-17 15:23:43             bmAttributes 0x2        BULK
2025-02-17 15:23:43             wMaxPacketSize 64
2025-02-17 15:23:43             bInterval 0
2025-02-17 15:23:43 I (838) CLASS: Getting Manufacturer string descriptor
2025-02-17 15:23:43 Realtek
2025-02-17 15:23:43 I (848) CLASS: Getting Product string descriptor
2025-02-17 15:23:43 USB 10/100 LAN
2025-02-17 15:23:43 I (848) CLASS: Getting Serial Number string descriptor
2025-02-17 15:23:43 00E04C3603D6```

I'm able to setup my ESP32S3 as a USB Host and obtain the above information, but I realise that I need to create a host device class, and then route LWIP via the USB Host so that my device can obtain an IP address from the DHCP server and route traffic over usb-ethernet.

Any advice on how to achieve this?

[hathach]

You need to implement host driver for the dongle

[gadget-man]

OK that's what I suspected, but I'm not quite sure where to start. Are there any examples of host drivers for other types of device that I could use as a reference point?

[hathach]

There is existing host driver for msc,hid,cdc for reference

[nitsuj102284]

I have the same question. What are the steps to get this working as a USB to Network host? My other device has a USB-C Connection and expects an http PUT request from the ESP32-S3.

[hathach]

firstly, we need to implement host driver for the dongle, then integrate it with an tcp/ip stack like lwip

[gadget-man]

I’ve started work on this. I’m using the esp-IDF cdc-acm host driver example as a guide. (https://github.com/espressif/esp-idf/tree/master/examples/peripherals/usb/host/cdc/cdc_acm_host)

I’ve managed to get the device configured as a host class using the 2nd configuration and am successfully receiving Ethernet connection and link speed change notifications (although I'm currently getting them repeatedly.

I’m hoping to start work on the bulk in/out data transfer over the next couple of days and connect these to netif. If anyone is able to help out with this, let me know and I’ll share the repo.

Alternatively, if there's a simpler way to do this by modifying an existing tinyUSB host class driver, I'd be grateful if somebody could point me in the right direction!

[hathach]

that is great to hear, you can make an draft PR to add the host driver. That will allow other people to chime in to discuss or submit patch.

[gadget-man]

Updated device configuration details based on the CDC (2nd) configuration:

Bus 020 Device 001: ID 0bda:8152  
Negotiated speed: High Speed (480Mbps)
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.10
  bDeviceClass            0 [unknown]
  bDeviceSubClass         0 [unknown]
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  idVendor           0x0bda 
  idProduct          0x8152 
  bcdDevice           20.00
  iManufacturer           1 
  iProduct                2 
  iSerial                 3 
  bNumConfigurations      2
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x0027
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xa0
      (Bus Powered)
      Remote Wakeup
    MaxPower              100mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           3
      bInterfaceClass       255 [unknown]
      bInterfaceSubClass    255 [unknown]
      bInterfaceProtocol      0 
      iInterface              0 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x02  EP 2 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x83  EP 3 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0002  1x 2 bytes
        bInterval               8
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x0050
    bNumInterfaces          2
    bConfigurationValue     2
    iConfiguration          0 
    bmAttributes         0xa0
      (Bus Powered)
      Remote Wakeup
    MaxPower              100mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           1
      bInterfaceClass         2 [unknown]
      bInterfaceSubClass      6 [unknown]
      bInterfaceProtocol      0 
      iInterface              5 CDC Communications Control
      CDC Header:
        bcdCDC               1.10
      CDC Union:
        bMasterInterface        0
        bSlaveInterface         1 
      CDC Ethernet:
        iMacAddress                      3 00E04C3603D6
        bmEthernetStatistics    0x00000000
        wMaxSegmentSize               1514
        wNumberMCFilters            0x0000
        bNumberPowerFilters              0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x83  EP 3 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0010  1x 16 bytes
        bInterval               8
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       0
      bNumEndpoints           0
      bInterfaceClass        10 [unknown]
      bInterfaceSubClass      0 [unknown]
      bInterfaceProtocol      0 
      iInterface              0 
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       1
      bNumEndpoints           2
      bInterfaceClass        10 [unknown]
      bInterfaceSubClass      0 [unknown]
      bInterfaceProtocol      0 
      iInterface              4 Ethernet Data
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x02  EP 2 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               0
Binary Object Store Descriptor:
  bLength                 5
  bDescriptorType        15
  wTotalLength       0x000c
  bNumDeviceCaps          1
  USB 2.0 Extension Device Capability:
    bLength                 7
    bDescriptorType        16
    bDevCapabilityType      2
    bmAttributes   0x00000002
      HIRD Link Power Management (LPM) Supported

[gadget-man]

I've managed to get a working usb host driver For CDC-ECM working on CherryUSB by taking their existing cdc-ecm implementation and re-writing the netif sections to work for ESP-NETIF. However, I would much rather use tinyUSB across the board due to its better implementation of device classes and deeper integration with espressif. Here's my working demo on CherryUSB: https://github.com/gadget-man/cherryusb. And I've got an almost working version of cdc-acm-host, however it never seems to send or receive any data - I think I'm missing some control commands on enumeration of the host device class: - I'm trying to set packet filter but it always fails: https://github.com/gadget-man/cherryusb

Some progress, at least....

[gadget-man]

OK I've had a chance to have more of a look at this now - a working version of cdc-ecm-host for integration with esp-idf is now working and available at https://github.com/gadget-man/cdc-acm-host. Any feedback appreciated!

[hathach]

great news, thank you for your effort. Unfortunately I am a bit busy atm, I will check this out later on whenever possible.

[nitsuj102284]

How would I integrate this on the ESP32-S3 to send http requests to a connected device?

[gadget-man]

How would I integrate this on the ESP32-S3 to send http requests to a connected device?

If you install the sample app from my link above, it will automatically connect when Ethernet is connected, linked to esp-netif. You can then make an http request in exactly the same way as you would if the device was connected to WiFi.

[FunDeckHermit]

Would this also allow Tethering from an Android device?

[gadget-man]

If your Android device in tethering mode acts as a cdc-ecm device, then I suspect this could be modified - currently it specifically waits for connection from two types of Realktec usb to ethernet adapter.