Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <dc06357e-2d4d-208f-d59d-c0f8bf4c1843@redhat.com>
Date:   Thu, 8 Dec 2022 17:38:57 +0100
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101
 Thunderbird/102.5.1
Subject: Re: [PATCH 0/9] platform/surface: aggregator: Improve target/source
 handling in SSH messages
Content-Language: en-US, nl
To:     Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc:     Maximilian Luz <luzmaximilian@gmail.com>,
        Jiri Kosina <jikos@kernel.org>,
        Sebastian Reichel <sre@kernel.org>,
        Mark Gross <markgross@kernel.org>,
        Jonathan Corbet <corbet@lwn.net>,
        platform-driver-x86@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-input@vger.kernel.org, linux-pm@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20221202223327.690880-1-luzmaximilian@gmail.com>
 <c09c9cef-14ac-2ab3-5e01-13189823a053@redhat.com>
 <CAO-hwJLHzRCJF96gKJwj7zCCPxRLoEw=cQ2w8=yLBOfyZz-c8w@mail.gmail.com>
From:   Hans de Goede <hdegoede@redhat.com>
In-Reply-To: <CAO-hwJLHzRCJF96gKJwj7zCCPxRLoEw=cQ2w8=yLBOfyZz-c8w@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Precedence: bulk

Hi,

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 :)
> 
> If you think the patches are OK, they are really small concerning the
> HID part, so feel free to take them through your tree Hans.

Thank you.

Regards,

Hans


>>> Maximilian Luz (9):
>>>   platform/surface: aggregator: Ignore command messages not intended for
>>>     us
>>>   platform/surface: aggregator: Improve documentation and handling of
>>>     message target and source IDs
>>>   platform/surface: aggregator: Add target and source IDs to command
>>>     trace events
>>>   platform/surface: aggregator_hub: Use target-ID enum instead of
>>>     hard-coding values
>>>   platform/surface: aggregator_tabletsw: Use target-ID enum instead of
>>>     hard-coding values
>>>   platform/surface: dtx: Use target-ID enum instead of hard-coding
>>>     values
>>>   HID: surface-hid: Use target-ID enum instead of hard-coding values
>>>   platform/surface: aggregator: Enforce use of target-ID enum in device
>>>     ID macros
>>>   platform/surface: aggregator_registry: Fix target-ID of base-hub
>>>
>>>  .../driver-api/surface_aggregator/client.rst  |  4 +-
>>>  .../driver-api/surface_aggregator/ssh.rst     | 36 ++++-----
>>>  drivers/hid/surface-hid/surface_hid.c         |  2 +-
>>>  drivers/hid/surface-hid/surface_kbd.c         |  2 +-
>>>  .../platform/surface/aggregator/controller.c  | 12 +--
>>>  .../platform/surface/aggregator/ssh_msgb.h    |  4 +-
>>>  .../surface/aggregator/ssh_request_layer.c    | 15 ++++
>>>  drivers/platform/surface/aggregator/trace.h   | 73 +++++++++++++++++--
>>>  .../platform/surface/surface_aggregator_hub.c |  8 +-
>>>  .../surface/surface_aggregator_registry.c     |  2 +-
>>>  .../surface/surface_aggregator_tabletsw.c     | 10 +--
>>>  drivers/platform/surface/surface_dtx.c        | 20 ++---
>>>  .../surface/surface_platform_profile.c        |  2 +-
>>>  drivers/power/supply/surface_battery.c        |  4 +-
>>>  drivers/power/supply/surface_charger.c        |  2 +-
>>>  include/linux/surface_aggregator/controller.h |  4 +-
>>>  include/linux/surface_aggregator/device.h     | 50 ++++++-------
>>>  include/linux/surface_aggregator/serial_hub.h | 40 ++++++----
>>>  18 files changed, 191 insertions(+), 99 deletions(-)
>>>
>>
>