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=-9.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 16B6FC43461 for ; Wed, 16 Sep 2020 00:31:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CBB3E2076B for ; Wed, 16 Sep 2020 00:31:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="owBOhW6E" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726710AbgIPAbQ (ORCPT ); Tue, 15 Sep 2020 20:31:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55586 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726726AbgIONox (ORCPT ); Tue, 15 Sep 2020 09:44:53 -0400 Received: from mail-ot1-x344.google.com (mail-ot1-x344.google.com [IPv6:2607:f8b0:4864:20::344]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 30363C061A31 for ; Tue, 15 Sep 2020 06:43:41 -0700 (PDT) Received: by mail-ot1-x344.google.com with SMTP id g10so3240051otq.9 for ; Tue, 15 Sep 2020 06:43:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=B9DG7AFGOCi4fDIA/pebWsaF98Vfs0PhS8LEaercJUM=; b=owBOhW6EC7dR5wsl+J+VKIlsez0gsh9VM0JvmxWSZxWow81fml9LtpKBl4uX3tavXV lElVW/PinQeJb5cLZZBBk/hdlHr1yq52Wkrb0rFD4RVn9+JEFDqKJU8Y7VZ5bhPUPNdA myx4gU3MvUS5aCqwKxtuOgU3CQJAApWfYy5D9KWp7VZd5rokkIOL6Q9OrP9I8YmnI7Mv 2PyW4S3jl2HsHVAiOLxJfZXZRs7z5AzcfxmmvFnMN//9OXoO3FQ/RI2Z3H0B74PlaAfI RpQegVQmIbVCJjxHPj8nkKUT7KsN2AiACJCN1d6eHiY+GRQkr0sp8YN6uRo0yzcY7IdA ICfQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=B9DG7AFGOCi4fDIA/pebWsaF98Vfs0PhS8LEaercJUM=; b=rzywPhjNdqa2hlj4O2UaNBfab7D90aep5YQwcEg3nKlCCxksKQeNrsc4W+utWqYp99 XagIomha2ANo+Anqu1M3VMbFT++6vy9eTriQ+VSm9XtvpLregU4Rw4+HCWHDvztUo0hl iDwHbMpvt64eHcWmh08JpaKhoSDgzlSgh1zqUFkpA5KMwCnI57sJxhWZDjhcYFQa1p51 TR1w7QFSucZxlA8X1OQkZe773bKOXC1TR4SXXHA/VyAW4o6bXMa+rb4TZws6SMS81PT6 59DUiqYG9O/lfhXUC4XbMmHaATJbgH6Wt0iqMTaw/JllTpvD2Fhh9uAsfnTaiAqJsa1a 9NsA== X-Gm-Message-State: AOAM5339EjPsFmpCqkdjVtFNxaEdRPTLyB6pe7amYvVj8WdVV6lGd+Gw u64x8Pr9NZFv1RUraYfWx7Zo0A== X-Google-Smtp-Source: ABdhPJwGr+GRet1pRxe3nZ/L2fOWfupvdFYKrPB2ph9ZOkRDUTpxsjgx1wdTPacAmCm2yl+UzZeslA== X-Received: by 2002:a9d:7b48:: with SMTP id f8mr13079469oto.297.1600177420799; Tue, 15 Sep 2020 06:43:40 -0700 (PDT) Received: from yoga ([2605:6000:e5cb:c100:8898:14ff:fe6d:34e]) by smtp.gmail.com with ESMTPSA id w19sm5635176otq.70.2020.09.15.06.43.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Sep 2020 06:43:40 -0700 (PDT) Date: Tue, 15 Sep 2020 08:43:35 -0500 From: Bjorn Andersson To: nguyenb@codeaurora.org Cc: cang@codeaurora.org, asutoshd@codeaurora.org, martin.petersen@oracle.com, linux-scsi@vger.kernel.org, linux-arm-msm@vger.kernel.org, Rob Herring , Avri Altman , Vinod Koul , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , open list Subject: Re: [PATCH v1 1/2] scsi: dt-bindings: ufs: Add vcc-voltage-level for UFS Message-ID: <20200915134335.GE670377@yoga> References: <0a9d395dc38433501f9652a9236856d0ac840b77.1598939393.git.nguyenb@codeaurora.org> <20200915044154.GB670377@yoga> <748d238a3d9e53834a498c6f37f9f3c9@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <748d238a3d9e53834a498c6f37f9f3c9@codeaurora.org> Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Tue 15 Sep 03:14 CDT 2020, nguyenb@codeaurora.org wrote: > On 2020-09-14 21:41, Bjorn Andersson wrote: > > On Tue 01 Sep 01:00 CDT 2020, Bao D. Nguyen wrote: > > > > > UFS's specifications supports a range of Vcc operating > > > voltage levels. Add documentation for the UFS's Vcc voltage > > > levels setting. > > > > > > Signed-off-by: Can Guo > > > Signed-off-by: Asutosh Das > > > Signed-off-by: Bao D. Nguyen > > > --- > > > Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt | 2 ++ > > > 1 file changed, 2 insertions(+) > > > > > > diff --git a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt > > > b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt > > > index 415ccdd..7257b32 100644 > > > --- a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt > > > +++ b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt > > > @@ -23,6 +23,8 @@ Optional properties: > > > with "phys" attribute, provides phandle > > > to UFS PHY node > > > - vdd-hba-supply : phandle to UFS host controller supply > > > regulator node > > > - vcc-supply : phandle to VCC supply regulator node > > > +- vcc-voltage-level : specifies voltage levels for VCC supply. > > > + Should be specified in pairs (min, max), > > > units uV. > > > > What exactly are these pairs representing? > The pair is the min and max Vcc voltage request to the PMIC chip. > As a result, the regulator output voltage would only be in this range. > If you have static min/max voltage constraints for a device on a particular board the right way to handle this is to adjust the board's regulator-min-microvolt and regulator-max-microvolt accordingly - and not call regulator_set_voltage() from the river at all. In other words, you shouldn't add this new property to describe something already described in the node vcc-supply points to. Regards, Bjorn > > > > Is this supposed to be 3 pairs of (min,max) for vcc, vcc and vccq2 to be > > passed into a regulator_set_voltage() for each regulator? > Yes, that's right. I should include the other power supplies in this change > as well. > > > > Or are these some sort of "operating points" for the vcc-supply? > > > > Regards, > > Bjorn > > > > > - vccq-supply : phandle to VCCQ supply regulator node > > > - vccq2-supply : phandle to VCCQ2 supply regulator node > > > - vcc-supply-1p8 : For embedded UFS devices, valid VCC range > > > is 1.7-1.95V > > > -- > > > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora > > > Forum, > > > a Linux Foundation Collaborative Project > > >