From: PrasannaKumar Muralidharan Subject: Re: [PATCH v1 2/2] hw_random: timeriomem_rng: Allow setting RNG quality from platform data Date: Thu, 18 May 2017 11:13:29 +0530 Message-ID: References: <20170517222911.9295-1-raltherr@google.com> <20170517222911.9295-2-raltherr@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Cc: linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, Thomas Gleixner , Herbert Xu , Matt Mackall To: Rick Altherr Return-path: Received: from mail-vk0-f66.google.com ([209.85.213.66]:33437 "EHLO mail-vk0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751348AbdERFna (ORCPT ); Thu, 18 May 2017 01:43:30 -0400 In-Reply-To: <20170517222911.9295-2-raltherr@google.com> Sender: linux-crypto-owner@vger.kernel.org List-ID: Hi Rick, Minor comment below. On 18 May 2017 at 03:59, Rick Altherr wrote: > When a hw_random device's quality is non-zero, it will automatically be > used to fill the kernel's entropy pool. Since timeriomem_rng is used by > many different devices, the quality needs to be provided by platform > data or device tree. > > Signed-off-by: Rick Altherr > --- > > drivers/char/hw_random/timeriomem-rng.c | 7 +++++++ > include/linux/timeriomem-rng.h | 3 +++ > 2 files changed, 10 insertions(+) > > diff --git a/drivers/char/hw_random/timeriomem-rng.c b/drivers/char/hw_random/timeriomem-rng.c > index a0faa5f05deb..03ff5483d865 100644 > --- a/drivers/char/hw_random/timeriomem-rng.c > +++ b/drivers/char/hw_random/timeriomem-rng.c > @@ -151,8 +151,15 @@ static int timeriomem_rng_probe(struct platform_device *pdev) > dev_err(&pdev->dev, "missing period\n"); > return -EINVAL; > } > + > + if (!of_property_read_u32(pdev->dev.of_node, > + "quality", &i)) > + priv->rng_ops.quality = i; > + else > + priv->rng_ops.quality = 0; > } else { > period = pdata->period; > + priv->rng_ops.quality = pdata->quality; > } > > priv->period = ns_to_ktime(period * NSEC_PER_USEC); > diff --git a/include/linux/timeriomem-rng.h b/include/linux/timeriomem-rng.h > index 46eb27ddbfab..320f743bf06b 100644 > --- a/include/linux/timeriomem-rng.h > +++ b/include/linux/timeriomem-rng.h > @@ -13,4 +13,7 @@ struct timeriomem_rng_data { > > /* measures in usecs */ > unsigned int period; > + > + /* bits of entropy per 1000 bits read */ Your dt-bindings patch says 'entropy per 1024 bits'. Please be consistent. > + unsigned int quality; > }; > -- > 2.13.0.303.g4ebf302169-goog > Regards, PrasannaKumar