From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH v2 1/2] Input: Add device_enable handler to DaVinci Keyscan platform data Date: Thu, 19 Nov 2009 08:55:10 -0800 Message-ID: <20091119165509.GA15647@core.coreip.homeip.net> References: <1258141434-18351-1-git-send-email-miguel.aguilar@ridgerun.com> <20091119025946.GC20172@core.coreip.homeip.net> <4B057315.5070302@ridgerun.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-px0-f180.google.com ([209.85.216.180]:51847 "EHLO mail-px0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752168AbZKSQzK (ORCPT ); Thu, 19 Nov 2009 11:55:10 -0500 Received: by pxi10 with SMTP id 10so1755713pxi.33 for ; Thu, 19 Nov 2009 08:55:15 -0800 (PST) Content-Disposition: inline In-Reply-To: <4B057315.5070302@ridgerun.com> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Miguel Aguilar Cc: davinci-linux-open-source@linux.davincidsp.com, nsnehaprabha@ti.com, linux-input@vger.kernel.org, todd.fischer@ridgerun.com, diego.dompe@ridgerun.com, clark.becker@ridgerun.com, santiago.nunez@ridgerun.com On Thu, Nov 19, 2009 at 10:32:21AM -0600, Miguel Aguilar wrote: > Hi Dmitry, > >>> + if (pdata->device_enable) { >>> + error = pdata->device_enable(dev); >>> + if (error < 0) { >>> + dev_dbg(dev, "device enable function failed\n"); >>> + return error; >>> + } >>> + } >>> + >> >> Hi Miguel, >> >> Does this need to live in the driver? Why can't platform code do this >> for us? >> >> Thanks. >> > > The reason to invoke the device_enable function in the driver is because > in the testing process of the key scan driver a issue was found when the > key scan is built as a module. > > There is a specific PINMUX configuration that only should be set if the > key scan driver is loaded in the kernel to avoid pin conflicts. So when > the key scan is built as a module the board file (or platform code) > doesn't know if the key scan is loaded or not, so that's why the driver > is the one who must invoke the device_enable function in the probe > function. > I see... What happens if PINMUX is set but there isn't a driver? Also, what happens when you unload the module? Don't you need a similar call to disable PINMUX configuration? -- Dmitry