From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 396EBECE560 for ; Mon, 17 Sep 2018 13:50:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C6423214C2 for ; Mon, 17 Sep 2018 13:50:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C6423214C2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=opensource.cirrus.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728400AbeIQTRw (ORCPT ); Mon, 17 Sep 2018 15:17:52 -0400 Received: from mx0a-001ae601.pphosted.com ([67.231.149.25]:55498 "EHLO mx0b-001ae601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726865AbeIQTRw (ORCPT ); Mon, 17 Sep 2018 15:17:52 -0400 Received: from pps.filterd (m0077473.ppops.net [127.0.0.1]) by mx0a-001ae601.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w8HDkE0P012092; Mon, 17 Sep 2018 08:50:18 -0500 Authentication-Results: ppops.net; spf=none smtp.mailfrom=ckeepax@opensource.cirrus.com Received: from mail1.cirrus.com ([141.131.3.20]) by mx0a-001ae601.pphosted.com with ESMTP id 2mgyg0u1a4-1; Mon, 17 Sep 2018 08:50:18 -0500 Received: from EX17.ad.cirrus.com (unknown [172.20.9.81]) by mail1.cirrus.com (Postfix) with ESMTP id F02CB611E120; Mon, 17 Sep 2018 08:50:17 -0500 (CDT) Received: from imbe.wolfsonmicro.main (198.61.95.81) by EX17.ad.cirrus.com (172.20.9.81) with Microsoft SMTP Server id 14.3.408.0; Mon, 17 Sep 2018 14:50:17 +0100 Received: from imbe.wolfsonmicro.main (imbe.wolfsonmicro.main [198.61.95.81]) by imbe.wolfsonmicro.main (8.14.4/8.14.4) with ESMTP id w8HDoG8P022560; Mon, 17 Sep 2018 14:50:16 +0100 Date: Mon, 17 Sep 2018 14:50:16 +0100 From: Charles Keepax To: Rob Herring CC: Linus Walleij , Lee Jones , Michael Turquette , Stephen Boyd , Mark Brown , "Mark Rutland" , Liam Girdwood , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , "linux-kernel@vger.kernel.org" , Subject: Re: [PATCH 1/5] mfd: lochnagar: Add support for the Cirrus Logic Lochnagar Message-ID: <20180917135016.GK1653@imbe.wolfsonmicro.main> References: <20180905104120.17252-1-ckeepax@opensource.cirrus.com> <20180906144834.GD1653@imbe.wolfsonmicro.main> <5b9f3f61.1c69fb81.f4e64.f592@mx.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <5b9f3f61.1c69fb81.f4e64.f592@mx.google.com> User-Agent: Mutt/1.5.20 (2009-12-10) X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1809170140 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Sep 16, 2018 at 06:11:08PM -0500, Rob Herring wrote: > On Thu, Sep 06, 2018 at 03:48:34PM +0100, Charles Keepax wrote: > > On Thu, Sep 06, 2018 at 03:46:12PM +0200, Linus Walleij wrote: > > > On Wed, Sep 5, 2018 at 12:41 PM Charles Keepax > > > wrote: > > > It's a bit confusing, maybe you can clear it up: > > > it appears to be an I2C device, so when you say this is a > > > "development board" is there something like a board > > > controller that is accessed over I2C and this is what the > > > driver really probes to, not the board per se? > > > > > > I guess jamming this card into the I2C slot of any other > > > system (would work fine with a 96Boards LS connector > > > as it seems, actually) also involves connecting some > > > I2S or similar on the side for high-datarate traffic? > > > > > > This driver seems to only concern itself with the I2C > > > board controller per se, not the board is that right? > > > > > > > Yeah I have poorly phrased that, these patches are very much > > just dealing with the board controller chip. > > How would the codec I2C connect to the host? Is there one I2C bus or > 2? The binding looks mostly fine to me, but I think we need to > understand that part. > If the CODEC is I2C based then both the CODEC and the controller IC will be on the same I2C bus. If the CODEC is connected over SPI that is obviously a separate bus as the board controller chip is I2C only. There are some additional I2C interfaces but they are not currently used on any mini-cards, and they are intended for secondary purposes not control of the CODEC itself. Thanks, Charles