From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Gleixner Subject: Re: [PATCH] genirq: fix trigger flags check for shared irqs Date: Thu, 28 Jan 2016 21:06:20 +0100 (CET) Message-ID: References: <96c068ece0f5d01fc85bdbd9e0798f68180eebb8.1453204950.git.brian.starkey@arm.com> <20160128095955.GA12884@e106950-lin.cambridge.arm.com> <20160128111041.GB12884@e106950-lin.cambridge.arm.com> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Rob Herring Cc: Brian Starkey , LKML , Marc Zyngier , Tomasz Figa , Frank Rowand , Grant Likely , "devicetree@vger.kernel.org" List-Id: devicetree@vger.kernel.org On Thu, 28 Jan 2016, Rob Herring wrote: > On Thu, Jan 28, 2016 at 5:49 AM, Thomas Gleixner wrote: > > I've cc'ed the author and the device tree folks. Perhaps are they able to > > explain what this commit tries to 'fix'. > > It's certainly not clear what driver was being fixed. I think the > intention was to provide the trigger flags from the DT to drivers in a > standard, non-DT specific way. The implementation of it certainly > seems convoluted. The usecase I can think of is drivers may need the > trigger information for cases where the device can support different > trigger modes/polarity. The DT says which trigger mode to use and the > device and irqchip need to be programmed to match. IIRC, SMSC ethernet > chips frequently used on ARM boards do this. I can see that the driver wants this information, but why would one feed that back into request_irq() when the interrupt was already configured by DT. Still confused. Thanks, tglx