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Date:   Thu, 15 Nov 2018 16:28:26 +0100
From:   Boris Brezillon <boris.brezillon@bootlin.com>
To:     Wolfram Sang <wsa@the-dreams.de>
Cc:     vitor <vitor.soares@synopsys.com>, linux-i2c@vger.kernel.org,
        Jonathan Corbet <corbet@lwn.net>, linux-doc@vger.kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Arnd Bergmann <arnd@arndb.de>,
        Przemyslaw Sroka <psroka@cadence.com>,
        Arkadiusz Golec <agolec@cadence.com>,
        Alan Douglas <adouglas@cadence.com>,
        Bartosz Folta <bfolta@cadence.com>,
        Damian Kos <dkos@cadence.com>,
        Alicja Jurasik-Urbaniak <alicja@cadence.com>,
        Cyprian Wronka <cwronka@cadence.com>,
        Suresh Punnoose <sureshp@cadence.com>,
        Rafal Ciepiela <rafalc@cadence.com>,
        Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
        Nishanth Menon <nm@ti.com>, Rob Herring <robh+dt@kernel.org>,
        Pawel Moll <pawel.moll@arm.com>,
        Mark Rutland <mark.rutland@arm.com>,
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        Kumar Gala <galak@codeaurora.org>, devicetree@vger.kernel.org,
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        Stephen Boyd <swboyd@chromium.org>,
        Mark Brown <broonie@kernel.org>
Subject: Re: [PATCH v10 0/9] Add the I3C subsystem
Message-ID: <20181115162826.42b54776@bbrezillon>
In-Reply-To: <20181115150137.GB4169@kunai>
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On Thu, 15 Nov 2018 16:01:37 +0100
Wolfram Sang <wsa@the-dreams.de> wrote:

> Hi Boris,
> 
> > What we could do though, is expose I3C devices that do not have a
> > driver in kernel space, like spidev does.  
> 
> ...
> 
> > Mark, Wolfram, Arnd, Greg, any opinion?  
> 
> Is there a benefit for having drivers in userspace? My gut feeling is to
> encourage people to write kernel drivers. If this is, for some reason,
> not possible for some driver, then we have a use case at hand to test
> the then-to-be-developed userspace interface against. Until then, I
> personally wouldn't waste effort on designing it without a user in
> sight.

I kind of agree with that. Vitor, do you have a use case in mind for
such userspace drivers? I don't think it's worth designing an API for
something we don't need (yet).