Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755803AbbFOQBD (ORCPT ); Mon, 15 Jun 2015 12:01:03 -0400 Received: from avon.wwwdotorg.org ([70.85.31.133]:33130 "EHLO avon.wwwdotorg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754051AbbFOQA6 (ORCPT ); Mon, 15 Jun 2015 12:00:58 -0400 Message-ID: <557EF6D9.6050503@wwwdotorg.org> Date: Mon, 15 Jun 2015 10:01:29 -0600 From: Stephen Warren User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Ludovic Desroches CC: linux-arm-kernel@lists.infradead.org, linux-gpio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linus.walleij@linaro.org, nicolas.ferre@atmel.com Subject: Re: [RESEND PATCH 2/2] pinctrl: introduce complex pin description References: <1433948699-19800-1-git-send-email-ludovic.desroches@atmel.com> <1433948699-19800-3-git-send-email-ludovic.desroches@atmel.com> In-Reply-To: <1433948699-19800-3-git-send-email-ludovic.desroches@atmel.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1161 Lines: 22 On 06/10/2015 09:04 AM, Ludovic Desroches wrote: > Using a string to describe a pin in the device tree can be not enough. > Some controllers may need extra information to fully describe a pin. It > concerns mainly controllers which have a per pin muxing approach which > don't fit well the notions of groups and functions. > Instead of using a pin name, a 32 bit value is used. The 16 least > significant bits are used for the pin number. Other 16 bits can be used to > store extra parameters. The driver for the pin controller is supposed to provide this information in a table. The whole point of having a driver, rather than a table/list of raw register values in the DT, is so the driver can provide this information at a semantic level. This information is fixed per SoC and so make sense to put into a driver, while the board-specific configuration varies wildly, and hence makes sense to put into DT. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/