From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Porter Subject: Re: [RFC PATCH v3 11/16] mmc: omap_hsmmc: limit max_segs with the EDMA DMAC Date: Thu, 10 Jan 2013 14:30:28 -0500 Message-ID: <20130110193028.GP14660@beef> References: <1350566815-409-1-git-send-email-mporter@ti.com> <1350566815-409-12-git-send-email-mporter@ti.com> <508E3BE6.3070609@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Linux DaVinci Kernel List , Linux OMAP List , Russell King , Benoit Cousson , Arnd Bergmann , Linux Documentation List , Tony Lindgren , Devicetree Discuss , Mark Brown , Linux MMC List , Linux Kernel Mailing List , Rob Herring , Grant Likely , Vinod Koul , Rob Landley , Dan Williams , Linux SPI Devel List , Chris Ball , Linux ARM Kernel List To: Sekhar Nori Return-path: Content-Disposition: inline In-Reply-To: <508E3BE6.3070609@ti.com> Sender: linux-doc-owner@vger.kernel.org List-Id: linux-spi.vger.kernel.org On Mon, Oct 29, 2012 at 01:48:46PM +0530, Sekhar Nori wrote: > On 10/18/2012 6:56 PM, Matt Porter wrote: > > The EDMA DMAC has a hardware limitation that prevents supporting > > scatter gather lists with any number of segments. Since the EDMA > > DMA Engine driver sets the maximum segments to 16, we do the > > same. > > > > TODO: this will be replaced once the DMA Engine API supports an > > API to query the DMAC's segment size limit. > > > > Signed-off-by: Matt Porter > > --- > > drivers/mmc/host/omap_hsmmc.c | 10 ++++++++++ > > 1 file changed, 10 insertions(+) > > > > diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c > > index b327cd0..52bab01 100644 > > --- a/drivers/mmc/host/omap_hsmmc.c > > +++ b/drivers/mmc/host/omap_hsmmc.c > > @@ -1828,6 +1828,16 @@ static int __devinit omap_hsmmc_probe(struct platform_device *pdev) > > * as we want. */ > > mmc->max_segs = 1024; > > > > + /* Eventually we should get our max_segs limitation for EDMA by > > + * querying the dmaengine API */ > > Nit picking: This is not as per multi-line comment style in > Documentation/CodingStyle. Thanks :). This is dropped from v4 anyway, as I now use a call to dma_get_channel_caps() to determine the SG limits. -Matt