From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gary Bisson Subject: Re: [PATCH] Input: egalax_ts - do not release gpio if probe successful Date: Fri, 13 Jan 2017 00:03:43 +0100 Message-ID: <20170112230343.rt6e2qrhnvl4cvqq@x240.lan> References: <20170111172841.9825-1-gary.bisson@boundarydevices.com> <20170112183019.GB7475@dtor-ws> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20170112183019.GB7475@dtor-ws> Sender: linux-kernel-owner@vger.kernel.org To: Dmitry Torokhov Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-input@vger.kernel.org Hi Dmitri, On Thu, Jan 12, 2017 at 10:30:19AM -0800, Dmitry Torokhov wrote: > Hi Gary, > > On Wed, Jan 11, 2017 at 06:28:41PM +0100, Gary Bisson wrote: > > Thus preventing anyone to later modify the interrupt GPIO direction > > and/or state without the driver knowing. > > I am afraid not releasing gpio after waking up the controller will cause > request_irq to fail if we are using the same pin for interrupt and > wakeup (as majority of current DTSes do: see > arch/arm/boot/dts/imx53-tx53-x13x.dts for example). No, keeping the GPIO doesn't prevent from requesting the IRQ. However it keeps other drivers/users from changing the GPIO as output later on. > You'll need to figure out if irq is backed by the same gpio as wakeup > and act accordingly. > > What setup did you test this on? Was it shared pin or dedicated wakeup? I've tested on i.MX6Q Nitrogen6x [1] with Hannstar 10" display [2]. Regards, Gary [1] https://boundarydevices.com/product/nitrogen6x-board-imx6-arm-cortex-a9-sbc/ [2] https://boundarydevices.com/product/nit6x_10-1hannstar/