XBox One Wireless Adapter v2 doesn't work

Edited: Used wrong firmware the first time, sorry about that... :-/

In order to avoid any confusion, it's this adapter:
https://mspoweruser.com/new-xbox-wireless-adapter-significantly-slimmer/

Hardware:
Orange Pi PC (Allwinner H3)

Software:
OpenWrt master (commit 212aa332267641fa9fc9a16d39159decec95b4a1)
https://github.com/openwrt/openwrt/pull/1460 + https://github.com/openwrt/openwrt/pull/1461

I tried adding the device id however that doesn't seem enough:
{ USB_DEVICE(0x045e, 0x02fe) }, /* XBox One Wireless Adapter v2 */

dmesg

[    8.284978] mt76x2u 3-1:1.0: ASIC revision: 76320044
[    8.345123] mt76x2u 3-1:1.0: ROM patch build: 20140408060640a
[    8.511399] mt76x2u 3-1:1.0: Firmware Version: 0.0.00
[    8.516489] mt76x2u 3-1:1.0: Build: 1
[    8.520148] mt76x2u 3-1:1.0: Build Time: 201406241830____
[    8.757481] mt76x2u 3-1:1.0: error: MCU resp evt:9 seq:1-0
[    8.762971] mt76x2u 3-1:1.0: error: MCU resp evt:9 seq:1-0
[    8.768482] mt76x2u 3-1:1.0: error: MCU resp evt:9 seq:1-0

lsusb (serial zeroed)

Bus 003 Device 002: ID 045e:02fe Microsoft Corp.
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.01
  bDeviceClass            0 (Defined at Interface level)
  bDeviceSubClass         0
  bDeviceProtocol         0
  bMaxPacketSize0        64
  idVendor           0x045e Microsoft Corp.
  idProduct          0x02fe
  bcdDevice            1.00
  iManufacturer           1 Microsoft Inc.
  iProduct                2 XBOX ACC
  iSerial                 3 000000
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength           74
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          2 XBOX ACC
    bmAttributes         0xa0
      (Bus Powered)
      Remote Wakeup
    MaxPower              500mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           8
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass    255 Vendor Specific Subclass
      bInterfaceProtocol    255 Vendor Specific Protocol
      iInterface              2 XBOX ACC
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x84  EP 4 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     0x85  EP 5 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     0x08  EP 8 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     0x04  EP 4 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     0x05  EP 5 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     0x06  EP 6 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     0x07  EP 7 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     0x09  EP 9 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           12
  bNumDeviceCaps          1
  USB 2.0 Extension Device Capability:
    bLength                 7
    bDescriptorType        16
    bDevCapabilityType      2
    bmAttributes   0x0000f41e
      Link Power Management (LPM) Supported
Device Status:     0x0002
  (Bus Powered)
  Remote Wakeup Enabled

Windows drivers can be obtained here (includes firmware):
http://www.catalog.update.microsoft.com/Search.aspx?q=xbox%20wireless%20adapter

18.X - 21.X seems to be for the older adapter
1.0.X is for the new one

Having a quick look at the drivers they're using different firmwares but that's as far as I can tell.
If there's anything else I can provide just ask and I'll try my best.

@LorenzoBianconi

Start at the mt76x2u USB-device handling and firmware-loading path; the report identifies USB ID 045e:02fe, MCU response errors, and separate old/new firmware versions. Confirm the adapter's required firmware and define done as successful initialization without those errors, then validate on the reported OpenWrt master commit and Orange Pi PC.