linux-kernel - Re: [PATCH v13 1/3] dt-bindings: i2c: Add CP2112 HID USB to SMBus Bridge

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <aXowcdIpdZwrc5KW@smile.fi.intel.com>
Date: Wed, 28 Jan 2026 17:51:13 +0200
From: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To: Conor Dooley <conor@...nel.org>
Cc: Krzysztof Kozlowski <krzk@...nel.org>,
	Danny Kaehn <danny.kaehn@...xus.com>, Rob Herring <robh@...nel.org>,
	Krzysztof Kozlowski <krzk+dt@...nel.org>,
	Benjamin Tissoires <bentiss@...nel.org>,
	Andi Shyti <andi.shyti@...nel.org>,
	Conor Dooley <conor+dt@...nel.org>, Jiri Kosina <jikos@...nel.org>,
	devicetree@...r.kernel.org, linux-input@...r.kernel.org,
	Dmitry Torokhov <dmitry.torokhov@...il.com>,
	Bartosz Golaszewski <bartosz.golaszewski@...aro.org>,
	Ethan Twardy <ethan.twardy@...xus.com>, linux-i2c@...r.kernel.org,
	linux-kernel@...r.kernel.org, Leo Huang <leohu@...dia.com>,
	Arun D Patil <arundp@...dia.com>, Willie Thai <wthai@...dia.com>,
	Ting-Kai Chen <tingkaic@...dia.com>
Subject: Re: [PATCH v13 1/3] dt-bindings: i2c: Add CP2112 HID USB to SMBus
 Bridge

On Wed, Jan 28, 2026 at 03:06:58PM +0000, Conor Dooley wrote:
> On Wed, Jan 28, 2026 at 02:49:39PM +0200, Andy Shevchenko wrote:
> > On Wed, Jan 28, 2026 at 11:35:25AM +0100, Krzysztof Kozlowski wrote:
> > > On Tue, Jan 27, 2026 at 10:02:17AM -0600, Danny Kaehn wrote:

...

> > > That's actually rule communicated many times, also documented in writing
> > > bindings and in recent talks.
> > 
> > Does DT represents HW in this case? Shouldn't I²C controller be the same node?
> > Why not? This is inconsistent for the device that is multi-functional. And from
> > my understanding the firmware description (DT, ACPI, you-name-it) must follow
> > the HW. I don't see how it's done in this case.
> 
> The i2c controller should probably be in the same node too, unless it
> would cause conflicts between function (e.g. inability to figure out if
> a child is a hog or a i2c device). I would like a rationale provided for
> why the i2c controller is in a subnode.

I can expect a disaster with such a scheme, splitting multi-functional device
to the subdevices (children) sounds to me like the best approach. With this,
one may have the same (globally named) property to be different on subdevices.

But I will hold my breath to see the outcome of this discussion.

-- 
With Best Regards,
Andy Shevchenko