From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Subject: Re: [V3 PATCH 3/5] device property: Introduces device_dma_is_coherent()
Date: Fri, 08 May 2015 22:49:09 +0200
Message-ID: <4329505.9FeAdJdNVY@vostro.rjw.lan>
References: <1431045436-8690-1-git-send-email-Suravee.Suthikulpanit@amd.com> <1431045436-8690-4-git-send-email-Suravee.Suthikulpanit@amd.com> <554C3790.4010407@oracle.com>
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Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>,
	lenb@kernel.org, catalin.marinas@arm.com, will.deacon@arm.com,
	thomas.lendacky@amd.com, herbert@gondor.apana.org.au,
	davem@davemloft.net, arnd@arndb.de, msalter@redhat.com,
	hanjun.guo@linaro.org, al.stone@linaro.org,
	grant.likely@linaro.org, leo.duran@amd.com,
	linux-arm-kernel@lists.infradead.org, linux-acpi@vger.kernel.org,
	linux-kernel@vger.kernel.org, linaro-acpi@lists.linaro.org,
	netdev@vger.kernel.org, linux-crypto@vger.kernel.org
To: "santosh.shilimkar@oracle.com" <santosh.shilimkar@oracle.com>
In-Reply-To: <554C3790.4010407@oracle.com>
Sender: linux-crypto-owner@vger.kernel.org

On Thursday, May 07, 2015 09:12:00 PM santosh.shilimkar@oracle.com wrote:
> On 5/7/15 5:37 PM, Suravee Suthikulpanit wrote:
> > Currently, device drivers, which support both OF and ACPI,
> > need to call two separate APIs, of_dma_is_coherent() and
> > acpi_dma_is_coherent()) to determine device coherency attribute.
> >
> > This patch simplifies this process by introducing a new device
> > property API, device_dma_is_coherent(), which calls the appropriate
> > interface based on the booting architecture.
> >
> > Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
> > ---
> >   drivers/base/property.c  | 12 ++++++++++++
> >   include/linux/property.h |  2 ++
> >   2 files changed, 14 insertions(+)
> >
> > diff --git a/drivers/base/property.c b/drivers/base/property.c
> > index 1d0b116..8123c6e 100644
> > --- a/drivers/base/property.c
> > +++ b/drivers/base/property.c
> > @@ -14,6 +14,7 @@
> >   #include <linux/export.h>
> >   #include <linux/kernel.h>
> >   #include <linux/of.h>
> > +#include <linux/of_address.h>
> >   #include <linux/property.h>
> >
> >   /**
> > @@ -519,3 +520,14 @@ unsigned int device_get_child_node_count(struct device *dev)
> >   	return count;
> >   }
> >   EXPORT_SYMBOL_GPL(device_get_child_node_count);
> > +
> > +bool device_dma_is_coherent(struct device *dev)
> > +{
> > +	if (IS_ENABLED(CONFIG_OF) && dev->of_node)
> 
> Do you really need that IS_ENABLED(CONFIG_OF) ?
> In other words, dev->of_node should be null for !CONFIG_OF

Yes, but IS_ENABLED(CONFIG_OF) causes the check to be optimized away by the
compiler if CONFIG_OF is not enabled.


-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.