linux-kernel - Re: [PATCH v9 6/7] i2c: xiic: use numbered adapter registration

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: <1ac7be34-22b1-4d93-9957-fc7ade9a2649@lunn.ch>
Date: Tue, 3 Feb 2026 19:31:20 +0100
From: Andrew Lunn <andrew@...n.ch>
To: Abdurrahman Hussain <abdurrahman@...thop.ai>
Cc: Andy Shevchenko <andriy.shevchenko@...el.com>,
	Michal Simek <michal.simek@....com>,
	Andi Shyti <andi.shyti@...nel.org>, Rob Herring <robh@...nel.org>,
	Krzysztof Kozlowski <krzk+dt@...nel.org>,
	Conor Dooley <conor+dt@...nel.org>,
	linux-arm-kernel@...ts.infradead.org, linux-i2c@...r.kernel.org,
	linux-kernel@...r.kernel.org, devicetree@...r.kernel.org
Subject: Re: [PATCH v9 6/7] i2c: xiic: use numbered adapter registration

On Tue, Feb 03, 2026 at 10:14:49AM -0800, Abdurrahman Hussain wrote:
> 
> 
> > On Feb 3, 2026, at 7:45 AM, Andy Shevchenko <andriy.shevchenko@...el.com> wrote:
> > 
> > On Mon, Feb 02, 2026 at 08:37:23PM +0000, Abdurrahman Hussain via B4 Relay wrote:
> > 
> >> Use i2c_add_numbered_adapter() to allow platform devices to specify
> >> fixed bus numbers when needed.
> > 
> > Not sure about this. Doesn't it break the current approach? Please, double
> > check that.
> > 
> > -- 
> > With Best Regards,
> > Andy Shevchenko
> > 
> > 
> 
> If pdev->id is PLATFORM_DEVID_NONE(-1) then i2c_add_numbered_adapter()
> falls back to dynamic allocation and calls i2c_add_adapter().
> 
> Many existing i2c drivers use the same approach, see i2c-pxa.c and
> i2c-pnx.c etc.

It is not about if other drivers do this. Its about does this change
the behaviour of this driver, so that I2C busses get different IDs
then before, and so cause regressions?

You need to explain in the commit message why you think this is safe.

    Andrew