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Message-ID: <1434614901.2385.27.camel@x220>
Subject: Re: [PATCH] driver/i2c/mux: Add register based mux i2c-mux-reg
From: Paul Bolle <pebolle@tiscali.nl>
To: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: York Sun <yorksun@freescale.com>, wsa@the-dreams.de,
        linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org,
        Peter Korsgaard <peter.korsgaard@barco.com>
Date: Thu, 18 Jun 2015 10:08:21 +0200
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Hi Alexander,

On Thu, 2015-06-18 at 09:40 +0200, Alexander Sverdlin wrote:
> On 17/06/15 18:03, ext Paul Bolle wrote:
> >> You do not see the platform_device, because there are no users yet, put
> >> > this MODULE_ALIAS() is perfectly fine, it will allow automatic module loading
> >> > in non-DT case.
> > Do you mean that it will allow automatic module loading once the patch
> > that adds a struct platform_device with a "i2c-mux-reg" name lands?
> 
> Any platform code which will register the platform_device will trigger uevent and
> udevd will be able to find the module with this macro. This is a legacy alternative
> to device-tree approach.

That means I've correctly figured out the purpose of this
MODULE_ALIAS("platform:" stuff. Because it might actually be documented
somewhere but I managed to not stumble on that documentation.

With that out of the way: am I right in thinking there's currently no
platform code that triggers that uevent for
"MODALIAS=platform:i2c-mux-reg"? Because if there's no struct
platform_device taking care of that I think this MODULE_ALIAS() should
not be added, not yet.

Thanks,


Paul Bolle