From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH] Input: eeti_ts: Mark as CONFIG_BROKEN Date: Tue, 10 Apr 2012 11:10:47 +0100 Message-ID: <20120410101047.GQ24211@n2100.arm.linux.org.uk> References: <1333777207-4151-1-git-send-email-olof@lixom.net> <20120407070206.GA17623@core.coreip.homeip.net> <4F8089A9.6080704@raumfeld.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Olof Johansson Cc: Sven Neumann , Dmitry Torokhov , Haojian Zhuang , linux-kernel@vger.kernel.org, Daniel Mack , linux-input@vger.kernel.org, Daniel Mack , linux-arm-kernel@lists.infradead.org List-Id: linux-input@vger.kernel.org On Sat, Apr 07, 2012 at 01:32:31PM -0700, Olof Johansson wrote: > Haojian, I think it was probably premature to do the multiplatform > change like that, since it means that a PXA-only kernel has no mapping > from irq_to_gpio to pxa_irq_to_gpio. Can you please address this as a > fix for 3.4? Please fix ezx-pcap instead - it's broken as it currently stands by using irq_to_gpio(), and it's one reason why my randconfig builds on OMAP fail. The big problem is - what does this do: do { ... } while (gpio_get_value(irq_to_gpio(pcap->spi->irq))); if pcap->spi->irq has no GPIO associated with the interrupt? irq_to_gpio() probably returns some random number which might be some other GPIO in the system, and gpio_get_value() could oops if irq_to_gpio returns a negative or large positive number. To put it another way, according to the above code, irq_to_gpio() must always return a valid gpio for the IRQ even if the IRQ doesn't have a GPIO associated with it. This is a fine illustration of why irq_to_gpio() is just plain broken in its design.