From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [203.10.76.45]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mx.ozlabs.org", Issuer "CA Cert Signing Authority" (verified OK)) by bilbo.ozlabs.org (Postfix) with ESMTPS id 2E123B7131 for ; Mon, 15 Jun 2009 09:51:04 +1000 (EST) Date: Mon, 15 Jun 2009 01:50:53 +0200 From: "Hans J. Koch" To: Wolfram Sang Subject: Re: [PATCH 2/2] uio: add an of_genirq driver Message-ID: <20090614235053.GK3639@local> References: <20090614122136.GD3639@local> <20090614171406.GA1010@pengutronix.de> <20090614183357.GE3639@local> <20090614190533.GA7387@pengutronix.de> <20090614192359.GG3639@local> <4A355155.4020500@grandegger.com> <20090614203444.GH3639@local> <20090614220022.GB24323@pengutronix.de> <20090614230135.GI3639@local> <20090614234643.GA17791@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20090614234643.GA17791@pengutronix.de> Cc: devicetree-discuss@ozlabs.org, "Hans J. Koch" , linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, Greg KH List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Mon, Jun 15, 2009 at 01:46:43AM +0200, Wolfram Sang wrote: > > > driver. A user _has_ to setup irq, if there is none, he still has to set > > irq=UIO_IRQ_NONE. For that matter, 'not specified' and 'not found' is both > > the same bad thing. > > Hmm, what should I do? > > A typical interrupts-property in a device-tree is specified as: > > interrupts = <&irq_controller_node irq_number irq_sense>; > > Something like UIO_IRQ_NONE does not fit into this scheme, even more as it is > Linux-specific and device trees need to be OS independant. > > I'm pretty sure the correct way to state that you don't need an interrupt in > the device-tree is to simply not specify the above interrupt property. > > Well, yes, that means you can't distinguish between 'forgotten' and > 'intentionally left out'. I wonder if it is really that bad? If something does > not work (= one is missing interrupts), the first place to look at is the > device tree. If one does not see an interrupt-property, voila, problem solved. > > (Note that with my latest suggestion, a _wrong_ interrupt is handled the same > way as with platform_data. request_irq() should equally fail if the > return-value from irq_of_parse_and_map() is simply forwarded.) I agree. And assuming Alan is right, forget what I said about IRQ 0 being a valid interrupt number. Thanks, Hans > > -- > Pengutronix e.K. | Wolfram Sang | > Industrial Linux Solutions | http://www.pengutronix.de/ |