lantiq: upstream Linux efforts

[Martin Schiller]

On 2021-04-12 00:24, Hauke Mehrtens wrote:
> Hi,
> 
> On 4/11/21 7:51 PM, Martin Blumenstingl wrote:
>> Hello everyone,
>> 
>> you are included in this email because you have previously worked on
>> patches for the Lantiq SoCs upstream.
>> 
>> In the past updating the kernel version for the lantiq target in
>> OpenWrt was an unpleasant task.
>> There are many out-of-tree patches and some of them are breaking with
>> newer kernel versions.
>> 
>> To improve the situation I suggest using Rafał Miłecki's approach also
>> for the lantiq target:
>> He is submitting patches upstream, then backporting them to OpenWrt.
>> That way backports to the -stable tree are for free.
>> Other patches can simply be dropped during the next major kernel
>> version update (instead of having to rework them every time...).
> 
> I like this approach.

I also like this approach.

>> This approach however only works when there are active contributors 
>> upstream.
>> It brings the benefit of upstream code-reviews though - which in my
>> experience improves the quality of the resulting code.

I think there's quite a bit of work involved.

If you take for example the patch with the configurability of the LEDs
on the phys:
Hauke had already started one or more attempts to bring this upstream
[1], but this was "rejected" with the reason that this belongs in the
LED subsystem.

Now I found an interesting solution on the mailing list, which
implements this function as hw offloading of the netdev trigger. [2]

@Hauke: what do you think about this?

Furthermore there are some patches for the target lantiq, which
unfortunately don't contain any description and so we have to work out
the deeper sense or necessity of this patch again.

[1] https://www.spinics.net/lists/netdev/msg380196.html
[2] https://www.spinics.net/lists/linux-leds/msg17241.html