Date: Tue, 13 Dec 2016 16:33:15 +0100
From: Corentin Labbe <clabbe.montjoie@gmail.com>
To: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>, davem@davemloft.net,
        maxime.ripard@free-electrons.com, Chen-Yu Tsai <wens@csie.org>,
        linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v2] crypto: sun4i-ss: support the Security System PRNG
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On Tue, Dec 13, 2016 at 08:53:54PM +0530, PrasannaKumar Muralidharan wrote:
> > What do you think about those two solutions ?
> 
> I prefer the second solution's idea of using two files (/dev/hwrng and
> /dev/hwprng). Upon having a quick glance it looks like (based on
> current_rng == prng check) that your current implementation allows
> only one rng device to be in use at a time. It would be better to have
> both usable at the same time. So applications that need pseudo random
> data at high speed can use /dev/prng while applications that require
> true random number can use /dev/rng. Please feel free to correct if my
> understanding of the code is incorrect. Along with this change I think
> changing the algif_rng to use this code if this solution is going to
> be used.
> 

No, there could be both device at the same time.