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Subject: Re: Sense of soc bus? (was: [PATCH] base: soc: Export
 soc_device_to_device() helper)
To:     Geert Uytterhoeven <geert@linux-m68k.org>
Cc:     Neil Armstrong <narmstrong@baylibre.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Geert Uytterhoeven <geert+renesas@glider.be>,
        linux-realtek-soc@lists.infradead.org,
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From:   =?UTF-8?Q?Andreas_F=c3=a4rber?= <afaerber@suse.de>
Organization: SUSE Software Solutions Germany GmbH
Message-ID: <a0a6d71f-4fb7-51ce-fe33-74f9e588b791@suse.de>
Date:   Fri, 15 Nov 2019 13:00:59 +0100
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Hi Geert,

Am 15.11.19 um 09:58 schrieb Geert Uytterhoeven:
> On Fri, Nov 15, 2019 at 9:52 AM Neil Armstrong <narmstrong@baylibre.com> wrote:
>> On 12/11/2019 11:47, Andreas Färber wrote:
>>> For example, RTD1295 will support LSADC only from revision B00
>>> on (and it's not the first time I'm seeing such things in the industry).
>>> So if a user complains, it will be helpful to see that information.
>>>
>>> Referencing your Amlogic review, with all due respect for its authors,
>>> the common framework here just lets that information evaporate into the
>>> deeps of sysfs.
>>
>> Hopefully we never had the case where needed to use the soc info in drivers,
>> but now we have one and having such infrastructure already in-place will help.
>>
>> Renesas platforms makes a extensive usage of the soc info infrastructure to
>> figure out plenty of HW parameters at runtime and lower their DT changes.
> 
> 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?

Regards,
Andreas

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