From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756300Ab2BAOXR (ORCPT ); Wed, 1 Feb 2012 09:23:17 -0500 Received: from mail-pw0-f46.google.com ([209.85.160.46]:50639 "EHLO mail-pw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752760Ab2BAOXQ (ORCPT ); Wed, 1 Feb 2012 09:23:16 -0500 Date: Wed, 1 Feb 2012 22:35:34 +0800 From: Shawn Guo To: Stephen Warren Cc: Dong Aisheng-B29396 , "Linus Walleij (linus.walleij@linaro.org)" , "Sascha Hauer (s.hauer@pengutronix.de)" , "rob.herring@calxeda.com" , "kernel@pengutronix.de" , "cjb@laptop.org" , "Simon Glass (sjg@chromium.org)" , Dong Aisheng , Thomas Abraham , Tony Lindgren , "Grant Likely (grant.likely@secretlab.ca)" , "devicetree-discuss@lists.ozlabs.org" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" Subject: Re: Pinmux bindings proposal V2 Message-ID: <20120201143530.GA2203@S2101-09.ap.freescale.net> References: <74CDBE0F657A3D45AFBB94109FB122FF1780DAB4CE@HQMAIL01.nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <74CDBE0F657A3D45AFBB94109FB122FF1780DAB4CE@HQMAIL01.nvidia.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Stephen, I had a talk with Dong about this binding, and we think that it should work well for imx if we have a couple of small pieces added. On Fri, Jan 20, 2012 at 02:22:20PM -0800, Stephen Warren wrote: ... > pmx_sdhci: pinconfig-sdhci { > /* > * The mux property is a list of muxable entities > * and the mux function to select for it. The number > * of cells in each entry is the pin controller's > * #pinmux-cells property. The pin controller's > * binding defines what the cells mean. The pinctrl > * driver is responsible for mapping this data to > * the (group, function) pair required to fill in > * the pinctrl subsystem's pinmux mapping table. > */ > mux = > > ; We need a property like 'mux-unit' whose value can be either 'pin' or 'pingroup' to reflect something you mentioned as muxable entity. The reason behind this is the DT logic inside pinctrl core needs to know how the pinmux_map should be constructed from device tree. In tegra case, the 'mux-unit' is 'pingroup', the core should construct pinmux_map entry for each row/element of 'mux'. In imx case, the 'mux-unit' will be 'pin', and we would expect core construct only one pinmux_map entry there, with all the pins listed in 'mux' composing the group that pinmux_map needs. And in case of 'mux-unit' is 'pin', we would need one more property 'mux-name' to present the group name. Then we have all the pieces to construct pinmux_map for cases like imx, where we do not define all those functions, groups in pinctrl driver at all. Regards, Shawn > /* > * The config property is a list of muxable entities > * and individual configuration setting. The number > * of cells in each entry is the pin controller's > * #pinconfig-cells property. The pin controller's > * binding defines what the cells mean. The pinctrl > * driver is responsible for mapping this data to > * the (group, config) pair required to fill in > * the pinctrl subsystem's pin configuration table. > */ > config = > > > > ; > };