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Date:   Mon, 18 Nov 2019 07:55:39 -0800
From:   Tony Lindgren <tony@atomide.com>
To:     Geert Uytterhoeven <geert@linux-m68k.org>
Cc:     Andreas =?utf-8?Q?F=C3=A4rber?= <afaerber@suse.de>,
        Neil Armstrong <narmstrong@baylibre.com>,
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        Geert Uytterhoeven <geert+renesas@glider.be>,
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        Bjorn Andersson <bjorn.andersson@linaro.org>,
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        Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= 
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Subject: Re: Sense of soc bus? (was: [PATCH] base: soc: Export
 soc_device_to_device() helper)
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* Geert Uytterhoeven <geert@linux-m68k.org> [191115 15:51]:
> On Fri, Nov 15, 2019 at 1:01 PM Andreas Färber <afaerber@suse.de> wrote:
> > Am 15.11.19 um 09:58 schrieb Geert Uytterhoeven:
> > > We do our best to use it solely for detecting quirks in early SoC revisions.
> >
> > Got a pointer? I fail to immediately understand how sysfs would help
> > drivers (as opposed to userspace) detect quirks: Parsing strings back
> > doesn't sound efficient, and I don't see you exporting any custom APIs
> > in drivers/soc/renesas/renesas-soc.c?
> 
> We use soc_device_match(), inside kernel drivers.
> Exposure through sysfs is a side-effect of using soc_device_register(),
> and welcomed, as it allows the user to find out quickly which SoC and
> revision is being used.

For the omap variants too, we've so far gotten away with early SoC
detection for platform code, and then use soc_device_match() in few
cases for drivers at probe time if needed.

Regards,

Tony