From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yegor Yefremov Subject: Re: [PATCH] Input: TPS6507X - define MFD dependencies for touch and regulator unit Date: Tue, 12 Jul 2011 10:23:24 +0200 Message-ID: <4E1C047C.2080508@visionsystems.de> References: <4E1AD56B.6080306@visionsystems.de> <20110711122004.GA9478@sirena.org.uk> <20110711164124.GB1648@core.coreip.homeip.net> <20110711223312.GA32033@opensource.wolfsonmicro.com> Reply-To: yegor_sub1@visionsystems.de Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from hhlx01.visionsystems.de ([62.145.30.242]:35830 "EHLO mail.visionsystems.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751259Ab1GLIXd (ORCPT ); Tue, 12 Jul 2011 04:23:33 -0400 In-Reply-To: <20110711223312.GA32033@opensource.wolfsonmicro.com> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Mark Brown Cc: Dmitry Torokhov , linux-input@vger.kernel.org Am 12.07.2011 00:33, schrieb Mark Brown: > On Mon, Jul 11, 2011 at 09:41:24AM -0700, Dmitry Torokhov wrote: >> On Mon, Jul 11, 2011 at 01:20:04PM +0100, Mark Brown wrote: >>> This isn't a good fix, the driver should depend on the MFD core not >>> select it. >> The problem with such dependencies is that user has to first enable MFD >> core and then hunt through all other menus in search of the function >> drivers for that chip... >> Depending on what other things TPS6507X depends on it might be good idea >> to go ahead and select it. > If this is an issue it's going to be much more useful to have the boards > select their MFD cores than have random function drivers do that, in > most situations it's not actually going to be useful to select the core > driver as the core driver itself needs something to select either the > I2C or SPI bus interface for the device in order to actually communicate > with it. > > Remember that this is for embedded systems where the user will normally > have a pretty good idea what's on their system, someone will have had to > explicitly plumb the device into the board anyway. The reason for the patch was following. I have a custom board, that is very close to some other board except of this PMIC (TPS650732). So I copied the platform code from the second board, but not the configuration. Then I activated the touchscreen driver and wondered, why on earth i2c driver doesn't see this device? At last I found out, that this driver depends on MFD driver and so I made this patch to avoid this situation in the future. Yegor