[PATCH v9 6/7] i2c: xiic: use numbered adapter registration

[Abdurrahman Hussain]

> On Feb 3, 2026, at 10:31 AM, Andrew Lunn <andrew at lunn.ch> wrote:
> 
> 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 at intel.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

Before, the driver was always doing the dynamic allocation due to
i2c_add_adapter(). So there could not have been a system that relied on
consistent i2c bus numbering. Even between reboots bus numbering could change.

The systems that did set pdev->id and were expecting a consistent i2c bus
numbering were broken to begin with.

This patch won’t break any existing systems or cause regressions.