[PATCH 5/8] usb: eth: Add CDC ECM support

[Marek Vasut]

On 7/12/26 11:08 AM, Jonas Karlman wrote:
> Hi Marek,
> 
> On 7/11/2026 9:57 PM, Marek Vasut wrote:
>> On 7/11/26 6:08 PM, Jonas Karlman wrote:
>>> Add support for CDC ECM (Communications Device Class, Ethernet Control
>>> Model) devices.
>>>
>>> References:
>>> - [USBECM12] USB Subclass Specification for Ethernet Control Model 1.2.
>>> - [USBCDC12] USB Class Definitions for Communications Devices 1.2.
>>> - [USB20] USB Specification 2.0.
>>>
>>> Signed-off-by: Jonas Karlman <jonas at kwiboo.se>
>> Is this pulled from Linux or is this written from scratch ?
> 
> As stated in the cover letter this driver was written from scratch.
> 
>    The driver implementations was created based of the CDC ECM 1.2 and
>    CDC NCM 1.1 specifications and was tested on a few different USB
>    Ethernet adapters using ASIX or Realtek IC.
> At some point I looked and compared to Linux to ensure ordering of e.g.
> control messages and size limitations where closely matched.
> 
> In more detail the NCM driver was first created and tested on AX88179.
> Later when tested on RTL815x there were some issues, so I also added the
> ECM variant and tested that on both AX88179 and RTL815x.
> 
> The ECM variant is likely enough for U-Boot purposes, however NCM still
> has some good features such as custom MAC-addresses. So, I included both
> in this series, with NCM being preferred over ECM due to driver list
> sorting.
OK