From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sascha Hauer Subject: Re: [PATCH 0/4 v6] i.MX31: dmaengine and framebuffer drivers Date: Tue, 6 Jan 2009 10:04:22 +0100 Message-ID: <20090106090422.GC18861@pengutronix.de> References: Mime-Version: 1.0 Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Guennadi Liakhovetski Cc: linux-kernel@vger.kernel.org, linux-fbdev-devel@lists.sourceforge.net, adaplas@gmail.com, linux-arm-kernel@lists.arm.linux.org.uk, Dan Williams , Geert Uytterhoeven Hi Guennadi, On Fri, Dec 26, 2008 at 06:11:13PM +0100, Guennadi Liakhovetski wrote: > Hi, > > This is version 6 of dmaengine and framebuffer drivers for i.MX31. > > Changes since version 5: as requested by Sascha Hauer switched to dynamic > IPU IRQ mapping. I tried to express that it's really odd that you demux your _internal_ interrupts as chained handlers. Consider a network driver which has a rx, tx and an error status bit, all of them can trigger an interrupt. A you aware of a single driver that uses chained interrupts for this case? No, they don't have to, because all this happens inside one driver and this can easily be dispatched in one interrupt handler. IMHO chained interrupts only make sense when you have an interrupt source which leaves your driver code and you don't know who might be interested in, like the assorted non channel interrupts the IPU also provides. I bet you'd never have the idea for such a code design without the Freescale code as a sample. Note that arch/arm/plat-mxc/include/mach/mx31.h does not apply anymore due to upstream changes. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |