Re: [PATCH 0/9] platform/surface: aggregator: Improve target/source handling in SSH messages

[Maximilian Luz <luzmaximilian@gmail.com>]

On 12/8/22 17:24, Benjamin Tissoires wrote:
> On Thu, Dec 8, 2022 at 5:03 PM Hans de Goede <hdegoede@redhat.com> wrote:
>>
>> Hi Maximilian,
>>
>> On 12/2/22 23:33, Maximilian Luz wrote:
>>> We have some new insights into the Serial Hub protocol, obtained through
>>> reverse engineering. In particular, regarding the command structure. The
>>> input/output target IDs actually represent source and target IDs of
>>> (what looks like) physical entities (specifically: host, SAM EC, KIP EC,
>>> debug connector, and SurfLink connector).
>>>
>>> This series aims to improve handling of messages with regards to those
>>> new findings and, mainly, improve clarity of the documentation and usage
>>> around those fields.
>>>
>>> See the discussion in
>>>
>>>      https://github.com/linux-surface/surface-aggregator-module/issues/64
>>>
>>> for more details.
>>>
>>> There are a couple of standouts:
>>>
>>> - Patch 1 ensures that we only handle commands actually intended for us.
>>>    It's possible that we receive messages not intended for us when we
>>>    enable debugging. I've kept it intentionally minimal to simplify
>>>    backporting. The rest of the series patch 9 focuses more on clarity
>>>    and documentation, which is probably too much to backport.
>>>
>>> - Patch 8 touches on multiple subsystems. The intention is to enforce
>>>    proper usage and documentation of target IDs in the SSAM_SDEV() /
>>>    SSAM_VDEV() macros. As it directly touches those macros I
>>>    unfortunately can't split it up by subsystem.
>>>
>>> - Patch 9 is a loosely connected cleanup for consistency.
>>
>> Thank you for the patches. Unfortunately I don't have time atm to
>> review this.
>>
>> And the next 2 weeks are the merge window, followed by 2 weeks
>> of christmas vacation.
>>
>> So I'm afraid that I likely won't get around to reviewing
>> this until the week of January 9th.
>>
>>> Hans, Jiri, Benjamin, Sebastian: While patch 8 ("platform/surface:
>>> aggregator: Enforce use of target-ID enum in device ID macros") touches
>>> multiple subsystems, it should be possible to take the whole series
>>> through the pdx86 tree. The changes in other subsystems are fairly
>>> limited.
>>
>> I agree that it will be best to take all of this upstream through the
>> pdx86 tree. Sebastian thank you for the ack for patch 8/9.
>>
>> Jiri or Benjamin may we have your ack for merging patch 7/9 + 8/9
>> through the pdx86 tree ?
> 
> I can give you an ack for taking those through your tree, but I can
> not review the patches themselves because I was only CC-ed to those 2,
> and so was linux-input. Given that SSAM_SSH_TID_KIP is not in my
> current tree I assume it comes from this series.
> 
> Anyway, enough ranting :)

Apologies for that. I should have included you in the CC on at least
patch 2 as well, which introduces this symbol.

FWIW, here's the patchwork link to this series:

   https://patchwork.kernel.org/project/platform-driver-x86/list/?series=701392

Regards,
Max