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Date: Wed, 29 Apr 2015 20:56:26 +0200
Message-ID: <CAMuHMdXtL=-JWiXNbpwBEc+oMAVpBq1ShqZhFVKZRO_x9Xq4tA@mail.gmail.com>
Subject: Re: [linux-sunxi] [PATCH 2/3] spidev: Add DT binding example.
From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Michal Suchanek <hramrach@gmail.com>
Cc: Mark Brown <broonie@kernel.org>, "Eric D." <eric.dillmann@gmail.com>,
        linux-sunxi <linux-sunxi@googlegroups.com>,
        Jonathan Corbet <corbet@lwn.net>, Hans de Goede <hdegoede@redhat.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Maxime Ripard <maxime.ripard@free-electrons.com>,
        linux-spi <linux-spi@vger.kernel.org>,
        Martin Sperl <kernel@martin.sperl.org>
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On Wed, Apr 29, 2015 at 8:37 PM, Michal Suchanek <hramrach@gmail.com> wrote:
> I am using a version of Maxime's patch myself right now. It does not
> seem it's going to be include in the kernel any time soon, however.
>
> FWIW I added the ability to open any CS, even those claimed by kernel
> drivers. This addresses any potential race of spidev binding before
> the actual driver but has the potential to introduce some subtle bugs
> when you open and reconfigure a CS used by a kernel driver or send
> some commands that upset the device.

Uh, that sounds dangerous.

Perhaps you can add some safety net, before user space can access
them, cfr. /sys/class/gpio/export?

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
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