From mboxrd@z Thu Jan 1 00:00:00 1970 From: mporter@ti.com (Matt Porter) Date: Thu, 10 Jan 2013 14:30:28 -0500 Subject: [RFC PATCH v3 11/16] mmc: omap_hsmmc: limit max_segs with the EDMA DMAC In-Reply-To: <508E3BE6.3070609@ti.com> References: <1350566815-409-1-git-send-email-mporter@ti.com> <1350566815-409-12-git-send-email-mporter@ti.com> <508E3BE6.3070609@ti.com> Message-ID: <20130110193028.GP14660@beef> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.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