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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B9E69FA3746 for ; Mon, 31 Oct 2022 19:41:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229668AbiJaTk7 (ORCPT ); Mon, 31 Oct 2022 15:40:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53082 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229549AbiJaTk6 (ORCPT ); Mon, 31 Oct 2022 15:40:58 -0400 Received: from aposti.net (aposti.net [89.234.176.197]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D1FEF62E1; Mon, 31 Oct 2022 12:40:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=crapouillou.net; s=mail; t=1667245255; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ev+MitsCvb12qgt/0r4BvM6yNG9k7Li3wHRVx265aw0=; b=hrfZgO2440u6WNNOd8DB0pQ/70uPdBsvk6fnaQaeMPBiWRo5HPWZ7bJb4WQAM1PepqQ0/D DcY9DaTMglBPI5KVPjwKdZEMm8zF6F69whlQ8hoGl63SBBQgsd7QWWGaGxlv9UUtkib0VN ktxAsvmugDhckF83ij6CGg3ZuumbQaI= Date: Mon, 31 Oct 2022 19:40:44 +0000 From: Paul Cercueil Subject: Re: [PATCH v2 1/4] dt-bindings: rtc: ingenic: Rework compatible strings and add #clock-cells To: Rob Herring Cc: Alessandro Zummo , Alexandre Belloni , Krzysztof Kozlowski , linux-rtc@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, od@opendingux.net Message-Id: In-Reply-To: <20221031192341.GA3270129-robh@kernel.org> References: <20221028225519.89210-1-paul@crapouillou.net> <20221028225519.89210-2-paul@crapouillou.net> <20221031192341.GA3270129-robh@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi Rob, Le lun. 31 oct. 2022 =E0 14:23:41 -0500, Rob Herring a=20 =E9crit : > On Fri, Oct 28, 2022 at 11:55:16PM +0100, Paul Cercueil wrote: >> The RTC in the JZ4770 is compatible with the JZ4760, but has an=20 >> extra >> register that permits to configure the behaviour of the CLK32K pin.=20 >> The >> same goes for the RTC in the JZ4780. >>=20 >> Therefore, the ingenic,jz4770-rtc and ingenic,jz4780-rtc strings do=20 >> not >> fall back anymore to ingenic,jz4760-rtc. The ingenic,jz4780-rtc=20 >> string >> now falls back to the ingenic,jz4770-rtc string. >=20 > This is a compatibility mess. There is no driver support in v6.1-rc=20 > for > ingenic,jz4770-rtc, so a new DT would not work with existing kernels.=20 > It > sounds like you need 3 compatibles for 4780. Do newer DTs need to work with older kernels? I always assumed the=20 compatibility was only enforced for the other way around. If that's the case though, I guess I can enforce 3 compatibles for 4780=20 and 2 for 4770 like you suggested. Cheers, -Paul >>=20 >> Additionally, since the RTCs in the JZ4770 and JZ4780 support=20 >> outputting >> the input oscillator's clock to the CLK32K pin, the RTC node is now=20 >> also >> a clock provider on these SoCs, so a #clock-cells property is added. >>=20 >> Signed-off-by: Paul Cercueil >> --- >>=20 >> v2: - add constraint on which SoCs can have the #clock-cells=20 >> property >> - add JZ4780 example which has a #clock-cells >>=20 >> .../devicetree/bindings/rtc/ingenic,rtc.yaml | 32=20 >> +++++++++++++++++-- >> 1 file changed, 30 insertions(+), 2 deletions(-)