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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 15284C3F2CD for ; Mon, 2 Mar 2020 16:13:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EAD072146E for ; Mon, 2 Mar 2020 16:13:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727183AbgCBQNn (ORCPT ); Mon, 2 Mar 2020 11:13:43 -0500 Received: from mail-oi1-f196.google.com ([209.85.167.196]:46788 "EHLO mail-oi1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726621AbgCBQNm (ORCPT ); Mon, 2 Mar 2020 11:13:42 -0500 Received: by mail-oi1-f196.google.com with SMTP id a22so10778402oid.13; Mon, 02 Mar 2020 08:13:41 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to; bh=wQyyrYKhl2IEkNe34AsK9CIVdMgcXzMGqPt74D0oPoI=; b=BjEToWRvD2dK2QDQVsWeFuMDh3mPeXGyaEStYhNNDoU7gOv3RzlMbJYPeGiyrE00/s y8FmXCBrXKefvbqJ8K+oIWOa/0psE51bmwxXFjRoVVf6EebxD0QGk8haluXHLRfs2L9t 4zPLBhHb6LbMMTFc1qL2BeuejtCFy0URVHXFw/5vkYyve668cCYnM4XH9wg/lr2uAGF2 NG/IYw8fc04kJw3Y3TkH04ZYTW6ppljAQnCXcnbu9lCBWV4aTMXzGcQsICoHdw7ZHAfv b80TuOZprpBeqHfnSCjThoTm9+uwX5Gx5T/uG617JkZ0m+2dAeq/rvsJPRHgW8WqAqFU N/RA== X-Gm-Message-State: ANhLgQ2ok++G6w+89LLA+15RbeWs9JsHMbUiqN1OUxaZ6sF6mVcSUIsD elzcXlcJ/+OBZaidwECwc2fSyFhV4SLCEow26JU= X-Google-Smtp-Source: ADFU+vtgX5P8l3pp8Byli/gDvMCPgCR1jBlOu2Z5pKiwIOplHm/8t6TqxYo4MB2Jy/30YCeHN5RgbSXCAHjgMhFgi3s= X-Received: by 2002:aca:ac4c:: with SMTP id v73mr185003oie.102.1583165621604; Mon, 02 Mar 2020 08:13:41 -0800 (PST) MIME-Version: 1.0 References: <20200113141556.GI3606@pflmari> <20200302134011.GA3717@pflmari> <20200302150706.GB3717@pflmari> <20200302160906.GC3717@pflmari> In-Reply-To: <20200302160906.GC3717@pflmari> From: Geert Uytterhoeven Date: Mon, 2 Mar 2020 17:13:30 +0100 Message-ID: Subject: Re: [PATCH 8/8] arm64: dts: renesas: salvator: add a connection from adv748x codec (HDMI input) to the R-Car SoC To: Alex Riesen , Geert Uytterhoeven , Kieran Bingham , Mauro Carvalho Chehab , Hans Verkuil , Laurent Pinchart , Rob Herring , Mark Rutland , driverdevel , Linux Media Mailing List , Linux Kernel Mailing List , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , Linux-Renesas Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Alex, On Mon, Mar 2, 2020 at 5:09 PM Alex Riesen wrote: > Geert Uytterhoeven, Mon, Mar 02, 2020 16:32:32 +0100: > > > And this absence of documentation also means that whatever clocks (both input > > > in "clocks=" and output in "#clock-cells") listed in a specific .dts are just > > > an integration detail? > > > > No, the absence probably means that any clock-related properties in a .dts > > file will just be ignored. > > > > Looking at the driver source, it indeed has no support related to clocks at all. > > ... > > > > Does this below makes more sense, than? > > > > > > video-receiver@70 { > > > compatible = "adi,adv7482"; > > > clocks = <&rcar_sound 3>; > > > clock-names = "clk-hdmi-video"; > > > adv748x_mclk: mclk { > > > compatible = "fixed-clock"; > > > #clock-cells = <0>; > > > /* frequency hard-coded for illustration */ > > > clock-frequency = <12288000>; > > > clock-output-names = "clk-hdmi-i2s-mclk"; > > > }; > > > }; > > > > The #clock-cells should be in the main video-receiver node. > > Probably there is more than one clock output, so #clock-cells may be 1? > > AFAICS, the device can provide only this one clock line (audio master clock > for I2S output)... I shall re-check, just in case. > > > There is no need for a fixed-clock compatible, nor for clock-frequency > > and clock-output-names. > > > > But most important: this should be documented in the adv748x DT bindings, > > and implemented in the adv748x driver. > > So if the driver is to export that clock for the kernel (like in this case), > it must implement its support? Exactly. Unless that pin is hardcoded to output a fixed clock, in which case you can just override the existing audio_clk_c rate. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds