Re: Sense of soc bus? (was: [PATCH] base: soc: Export soc_device_to_device() helper)

From: Tony Lindgren <tony@atomide.com>
To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: "Geert Uytterhoeven" <geert+renesas@glider.be>,
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Subject: Re: Sense of soc bus? (was: [PATCH] base: soc: Export soc_device_to_device() helper)
Date: Mon, 18 Nov 2019 07:55:39 -0800	[thread overview]
Message-ID: <20191118155539.GB35479@atomide.com> (raw)
In-Reply-To: <CAMuHMdU7EYHWRAR+s3ee4Wy6+6_MZON5xARszO7TDXZGyw8d5w@mail.gmail.com>

* 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

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