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Re: [PATCH] hw_random: Improve description of the ->read() interface

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On Thu, Aug 18, 2016 at 01:37:21PM +0100, Daniel Thompson wrote:
> Currently, very few RNG drivers support single byte reads using the
> ->read() interface. Of the 14 drivers in drivers/char/hw_random that
> support this interface only three of these actually support max == 1.
> The other behaviours vary between return 0, return 2, return 4 and return
> -EIO).
> 
> This is not a problem in practice because the core hw_random code never
> performs a read shorter than 16 bytes. The documentation for this function
> already contrains the alignment of the buffer pointer, so let's also
> guarantee that the buffer is at least as large as its alignment.
> 
> This constraint is intended to be the weakest guarantee neccessary to
> allow driver writers to safely simplify their code.
> 
> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>

Patch applied.  Thanks.
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

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[PATCH] hw_random: Improve description of the ->read() interface Daniel Thompson <daniel.thompson@linaro.org> - 2016-08-18 14:40 +0200
  Re: [PATCH] hw_random: Improve description of the ->read() interface Herbert Xu <herbert@gondor.apana.org.au> - 2016-08-24 15:20 +0200

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