From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH v3 6/7] dmaengine: omap-dma: Remove mapping between virtual channels and requests Date: Fri, 27 Mar 2015 20:22:30 +0000 Message-ID: <20150327202230.GA4027@n2100.arm.linux.org.uk> References: <1427459213-14611-1-git-send-email-peter.ujfalusi@ti.com> <1427459213-14611-7-git-send-email-peter.ujfalusi@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1427459213-14611-7-git-send-email-peter.ujfalusi@ti.com> Sender: linux-omap-owner@vger.kernel.org To: Peter Ujfalusi Cc: vinod.koul@intel.com, tony@atomide.com, grant.likely@linaro.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, robh+dt@kernel.org, nm@ti.com List-Id: devicetree@vger.kernel.org On Fri, Mar 27, 2015 at 02:26:52PM +0200, Peter Ujfalusi wrote: > Do not direct map the virtual channels to sDMA request number. When the > sDMA is behind of a crossbar this direct mapping can cause situations when > certain channel can not be requested since the crossbar request number > will no longer match with the sDMA request line. > The direct mapping for virtual channels with HW request lines will make it > harder to implement MEM_TO_MEM mode for the driver. There's no point having 127 virtual DMA channels then... is there? We might as well reduce the number down to a more reasonable set rather than wasting memory. > @@ -1049,7 +1050,6 @@ static int omap_dma_chan_init(struct omap_dmadev *od, int dma_sig) > return -ENOMEM; > > c->reg_map = od->reg_map; > - c->dma_sig = dma_sig; That's the only user of dma_sig in this function. Why not remove it from the function prototype and its caller? -- FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up according to speedtest.net.