From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932548Ab1LOQek (ORCPT ); Thu, 15 Dec 2011 11:34:40 -0500 Received: from metis.ext.pengutronix.de ([92.198.50.35]:38120 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932308Ab1LOQej (ORCPT ); Thu, 15 Dec 2011 11:34:39 -0500 Date: Thu, 15 Dec 2011 17:34:31 +0100 From: Sascha Hauer To: Shawn Guo Cc: Dong Aisheng-B29396 , Guo Shawn-R65073 , Linus Walleij , "linus.walleij@stericsson.com" , "linux-kernel@vger.kernel.org" , "rob.herring@calxeda.com" , "grant.likely@secretlab.ca" , "linux-arm-kernel@lists.infradead.org" , "kernel@pengutronix.de" Subject: Re: [RFC PATCH v2 4/4] mmc: sdhci-esdhc-imx: using pinmux subsystem Message-ID: <20111215163431.GV27267@pengutronix.de> References: <7FE21149F4667147B645348EC60578850564C5@039-SN2MPN1-013.039d.mgd.msft.net> <20111215093319.GO27267@pengutronix.de> <20111215112140.GA10522@S2101-09.ap.freescale.net> <7FE21149F4667147B645348EC60578850567C3@039-SN2MPN1-013.039d.mgd.msft.net> <20111215115300.GB10522@S2101-09.ap.freescale.net> <20111215115428.GQ27267@pengutronix.de> <20111215121752.GD10522@S2101-09.ap.freescale.net> <20111215132336.GR27267@pengutronix.de> <20111215140024.GA2963@S2100-06.ap.freescale.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20111215140024.GA2963@S2100-06.ap.freescale.net> X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-IRC: #ptxdist @freenode X-Accept-Language: de,en X-Accept-Content-Type: text/plain X-Uptime: 17:33:11 up 33 days, 20 min, 52 users, load average: 1.41, 2.96, 4.66 User-Agent: Mutt/1.5.21 (2010-09-15) X-SA-Exim-Connect-IP: 2001:6f8:1178:2:21e:67ff:fe11:9c5c X-SA-Exim-Mail-From: sha@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Dec 15, 2011 at 10:00:25PM +0800, Shawn Guo wrote: > On Thu, Dec 15, 2011 at 02:23:36PM +0100, Sascha Hauer wrote: > > On Thu, Dec 15, 2011 at 08:17:54PM +0800, Shawn Guo wrote: > > > On Thu, Dec 15, 2011 at 12:54:28PM +0100, Sascha Hauer wrote: > > > > On Thu, Dec 15, 2011 at 07:53:05PM +0800, Shawn Guo wrote: > > > > > On Thu, Dec 15, 2011 at 07:28:18PM +0800, Dong Aisheng-B29396 wrote: > > > > > > > -----Original Message----- > > > > > > > > > > > > > My understanding is that pinmux_get will return an error if no proper pinmux > > > > > > Found without dummy pinmux. That's a real error. > > > > > > But with dummy pinmux, if no proper pinmux found, the pinctrl core may check > > > > > > If dummy pinmux is supported, if supported, it will fakely success with returning > > > > > > a dummy pinmux. Then real error is hiden. > > > > > > This is due to for supporting one single image, the dummy pinmux may also be enabled > > > > > > For platforms like mx6q with real pinmux. > > > > > > > > > > > Got your point. So your concern is about the fake success when dummy > > > > > pinmux comes to play rather than 'fake error'. I'm not concerned about > > > > > that case much, since we will know the failure with a simple debug/info > > > > > message in the pinmux core, saying 'I do not find any available pinmux, > > > > > and I'm falling into the dummy pinmux'. When you see this message > > > > > imx6q, you know something goes wrong. > > > > > > > > So i.MX3/5 people must know that it's safe to ignore this message > > > > whereas i.MX6 people must know there's something wrong Adding messages > > > > saying "there might or might not be something wrong" is not good. > > > > People will frequently ask on the mailing list about these messages. > > > > > > > Usually, people checking the serial output and asking question on list > > > are developers not users. It's not too hard for developers to figure > > > out such message. Or we can making it a debug message, and when some > > > driver is not working, turn on debug option, you know where it goes > > > wrong. > > > > So we as developers have to figure out ourselves what can go wrong and > > the users, well who cares about users? > > > It's really the type of problem that can be discovered and fixed in > the development phase, isn't it? > > BTW, I did not mean to leave imx3 and imx5 there forever, but mean, > with the dummy pinmux support, we do not have to strictly migrate imx3, > imx5 and imx6 all at the same time. I'm afraid your plans for i.MX3/5 clash with Freescale's i.MX7 release... Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |