From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751591AbbBJPhA (ORCPT ); Tue, 10 Feb 2015 10:37:00 -0500 Received: from foss-mx-na.arm.com ([217.140.108.86]:42928 "EHLO foss-mx-na.foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751434AbbBJPg6 (ORCPT ); Tue, 10 Feb 2015 10:36:58 -0500 Date: Tue, 10 Feb 2015 15:36:28 +0000 From: Mark Rutland To: Boris Brezillon Cc: Thomas Gleixner , Jason Cooper , Nicolas Ferre , Jean-Christophe Plagniol-Villard , Alexandre Belloni , Rob Herring , Pawel Moll , Ian Campbell , Kumar Gala , "devicetree@vger.kernel.org" , "Rafael J. Wysocki" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v4 3/5] irqchip: Add DT binding doc for the virtual irq demuxer chip Message-ID: <20150210153628.GF9432@leverpostej> References: <1422527620-8308-1-git-send-email-boris.brezillon@free-electrons.com> <1422527620-8308-4-git-send-email-boris.brezillon@free-electrons.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1422527620-8308-4-git-send-email-boris.brezillon@free-electrons.com> Thread-Topic: [PATCH v4 3/5] irqchip: Add DT binding doc for the virtual irq demuxer chip Accept-Language: en-GB, en-US Content-Language: en-US User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Boris, On Thu, Jan 29, 2015 at 10:33:38AM +0000, Boris Brezillon wrote: > Add documentation for the virtual irq demuxer. > > Signed-off-by: Boris Brezillon > Acked-by: Nicolas Ferre > --- > .../bindings/interrupt-controller/dumb-demux.txt | 41 ++++++++++++++++++++++ > 1 file changed, 41 insertions(+) > create mode 100644 Documentation/devicetree/bindings/interrupt-controller/dumb-demux.txt > > diff --git a/Documentation/devicetree/bindings/interrupt-controller/dumb-demux.txt b/Documentation/devicetree/bindings/interrupt-controller/dumb-demux.txt > new file mode 100644 > index 0000000..b9a7830 > --- /dev/null > +++ b/Documentation/devicetree/bindings/interrupt-controller/dumb-demux.txt > @@ -0,0 +1,41 @@ > +* Virtual Interrupt Demultiplexer > + > +This virtual demultiplexer simply forward all incoming interrupts to its > +enabled/unmasked children. > +It is only intended to be used by hardware that do not provide a proper way > +to demultiplex a source interrupt, and thus have to wake all their children > +up so that they can possibly handle the interrupt (if needed). > +This can be seen as an alternative to shared interrupts when at least one > +of the interrupt children is a timer (and require the irq to stay enabled > +on suspend) while others are not. This will prevent calling irq handlers of > +non timer devices while they are suspended. This sounds like a DT-workaround for a Linux implementation problem, and I don't think this the right way to solve your problem. Why does this have to be in DT at all? Why can we not fix the core to handle these details? I am very much not keen on this binding. > + > +Required properties: > +- compatible: Should be "virtual,irq-demux". > +- interrupt-controller: Identifies the node as an interrupt controller. > +- interrupts-extended or interrupt-parent and interrupts: Reference the source > + interrupt connected to this dumb demuxer. > +- #interrupt-cells: The number of cells to define the interrupts (should be 1). > + The only cell is the IRQ number. > +- irqs: u32 bitfield specifying the interrupts provided by the demuxer. Arbitrary limitation? Thanks, Mark.