From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753188AbbCYTTu (ORCPT ); Wed, 25 Mar 2015 15:19:50 -0400 Received: from mout.gmx.net ([212.227.15.15]:60932 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752592AbbCYTTr (ORCPT ); Wed, 25 Mar 2015 15:19:47 -0400 Message-ID: <55130A4E.9010305@gmx.de> Date: Wed, 25 Mar 2015 20:19:42 +0100 From: Sergej Sawazki User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: Michael Turquette , linux-kernel@vger.kernel.org, jsarha@ti.com Subject: Re: clk: dt: bindings for mux-clock References: <550B44BA.4030401@gmx.de> <20150322171009.7930.25481@quantum> In-Reply-To: <20150322171009.7930.25481@quantum> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Provags-ID: V03:K0:2KMeoijdFFBvy9/F5GIFzc8tp6aFX0Wt+VwMBbUc3LP0Qlrf9Fk AZY9KhH9E23p+NTz74VZH8E5Em1EseS3NGT+PgM/xYts5mrpR4fh3Cf30cZDPNTmFIaUML8 gXsH+39LTrTqOpCr5s3EG68/wuRSBP1XOFxdyQ7l4rQpzOcnS6e8TqR5Rhi58ibUGDMhiqQ esYttqdlXQr0TQaHFGwrg== X-UI-Out-Filterresults: notjunk:1; Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am 22.03.2015 um 18:10 schrieb Michael Turquette: > Quoting Sergej Sawazki (2015-03-19 14:50:50) >> Hi Mike, >> >> I came across your "[PATCH v2 0/5] clk: dt: bindings for mux, divider & >> gate clocks" email from 16 Jun 2013. The DT bindings for simple clock >> multiplexers would be very helpful for a board I am working on. Do you >> see any chance to get it into mainline? > > Hi Sergej, > > I abandoned those binding a while back. The reason is that those are > one-node-per-clock bindings, which are unpopular with the DT crowd. > Instead most bindings today use a single node to represent a clock > provider, which maps onto a clock driver in Linux. > > Is your clock provider made up of only a single clock? If so then the > bindings you mentioned above may be appropriate. But if you have a clock > controller IP block that manages several clocks then it is better for > you to follow the clock provider binding style. There is no shortage of > good examples on how to do this. See the QCOM, Samsung and Nvidia > bindings for ideas. > > Regards, > Mike > >> >> Many thanks in advance! >> Regards, >> Sergej Hi Mike, many thanks for your answer. My clock provider is made up of two external oscillators and an external clock multiplexer. The clock multiplexer has two inputs and one output. See IDT 853S01I for example. The oscillators are connected to the multiplexer inputs. The clock consumer is connected to the output of the multiplexer. The multiplexer is controlled by a gpio to select one of the oscillators. Based on clk-gpio-gate.c, I am considering to develop a driver for a gpio controlled clock multiplexer. Do you think it makes sense? Or should I choose a different approach? Regards, Sergej