From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [PATCH] ata: libata depends on HAS_DMA Date: Fri, 15 May 2009 13:16:30 +0200 Message-ID: <200905151316.31521.arnd@arndb.de> References: <20090513043409.GA13577@cynthia.pants.nu> <20090514091928R.fujita.tomonori@lab.ntt.co.jp> <4A0CFE1F.5080409@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <4A0CFE1F.5080409@gmail.com> Content-Disposition: inline Sender: linux-m68k-owner@vger.kernel.org To: Tejun Heo Cc: FUJITA Tomonori , hancockrwd@gmail.com, alan@lxorguk.ukuu.org.uk, flar@allandria.com, schmitz@biophys.uni-duesseldorf.de, linux-kernel@vger.kernel.org, jgarzik@pobox.com, linux-ide@vger.kernel.org, takata@linux-m32r.org, geert@linux-m68k.org, linux-m68k@vger.kernel.org, ysato@users.sourceforge.jp List-Id: linux-ide@vger.kernel.org On Friday 15 May 2009, Tejun Heo wrote: > FUJITA Tomonori wrote: > > Can libata call dma_supported() per device to decide DMA or PIO mod= e? > > Then, we can solve this problem by add dummy DMA API (just calls BU= G) > > on such architectures, without Kconfig magic or adding ifdef (like = the > > old ide stack does), I think. That would be the !CONFIG_PCI half of the old include/asm-generic/dma-mapping.h file that you just removed, right? In general, I'd prefer keeping the asm-generic/dma-mapping-broken.h implementation that gives us a compile-time error, but maybe there is an even better option based on the mn10300 implementation which basically pretends everything works with just page_to_phys() mappings. > Sure it can. =A0Which specific drivers are we talking about? The main problem is libata-core.c, which references DMA mapping API calls that are only implemented on architectures setting CONFIG_HAS_DMA. Arnd <>< -- To unsubscribe from this list: send the line "unsubscribe linux-m68k" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html