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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C73FAECAAD8 for ; Wed, 31 Aug 2022 03:07:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Date:CC:To:From:Subject:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=B6Yzuc6DET4JwVYtcR5HPh/ULjS1Dwjj/JWqlLskPxE=; b=zL+sXSujy5mbDb ZjZrz19g506Lg5ptU/IYK31K8jZZx/dE2CV+6zTC8HwaQWUh/BS7rGAJJXYB7jIjGtDbVLIjexep8 pnFRtm9MR29kNWjmfb+I4LDZQMqYkeCjYXf+aXfBxlmv88CNy81384BL8gDFJXrcg1zphkmPVnp4O mpCJ/21wASmdHTyre2VvV6hRpWmLgU/QUIP4hMgVPCFkLv+TMNYvvejoh7TIiwD1ow32x3cEqSvwM LIcY7cf73R0trchfs2/UmTW6E9UX1gUKnDBhmQxTbzwO4FF6ksfD6j7E1RbCJO9GRNl/yPppGOn3b bglr7MhVgcTGHwoTbxGg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oTE3l-003OAA-1P; Wed, 31 Aug 2022 03:06:33 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oTE3g-003O1y-Mc; Wed, 31 Aug 2022 03:06:30 +0000 X-UUID: 8d98fb4414954f078e12e4856591e840-20220830 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Transfer-Encoding:MIME-Version:Content-Type:References:In-Reply-To:Date:CC:To:From:Subject:Message-ID; bh=gV2SyRTcZm810DhGZ3x0mIBFqGbS1GVUpw4cZ3uMVFw=; b=hGqJ1hS7dOKFrcPQ19oy3iz47p9MPxpmS56VXqwzUM/wcWEgWTrQn352oQsbN5oxeXFUYkcRQZ2brKLHEqbYnHZFBbdICT+1l+7Ls0QTxs7x2+wn3Qep6zaqncSNE0T8qRaKgV0K0CsP/oh7M8eXAss6K5nCMqDnlFNvMs71Hno=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.10,REQID:2ea4c90b-a010-4317-ba71-f80d7d7da7b8,OB:0,L OB:0,IP:0,URL:0,TC:0,Content:0,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_ Ham,ACTION:release,TS:0 X-CID-META: VersionHash:84eae18,CLOUDID:7d591656-e800-47dc-8adf-0c936acf4f1b,C OID:IGNORED,Recheck:0,SF:nil,TC:nil,Content:0,EDM:-3,IP:nil,URL:11|1,File: nil,Bulk:nil,QS:nil,BEC:nil,COL:0 X-UUID: 8d98fb4414954f078e12e4856591e840-20220830 Received: from mtkmbs11n1.mediatek.inc [(172.21.101.185)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 1782453035; Tue, 30 Aug 2022 20:01:34 -0700 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkmbs10n2.mediatek.inc (172.21.101.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.792.3; Wed, 31 Aug 2022 11:00:59 +0800 Received: from mhfsdcap04 (10.17.3.154) by mtkcas11.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Wed, 31 Aug 2022 11:00:57 +0800 Message-ID: <8dcb4de53a52ab44d40f490099b6ed13e5ef7fe0.camel@mediatek.com> Subject: Re: [PATCH 2/7] dt-bindings: phy: mediatek,tphy: add property to set pre-emphasis From: Chunfeng Yun To: Krzysztof Kozlowski , Vinod Koul , Rob Herring CC: Kishon Vijay Abraham I , Krzysztof Kozlowski , Matthias Brugger , , , , , , Eddie Hung Date: Wed, 31 Aug 2022 11:00:57 +0800 In-Reply-To: <0a82842d-283c-e266-84f4-6306f29b61da@linaro.org> References: <20220819091344.2274-1-chunfeng.yun@mediatek.com> <20220819091344.2274-2-chunfeng.yun@mediatek.com> <438da392-f419-ad76-7e91-aa4aab36e12c@linaro.org> <816ecf6287533137b750c8bde9de5830e4229c56.camel@mediatek.com> <1a16cce9fe164bafc06ae193310be71c6f645d75.camel@mediatek.com> <000babd8-5980-3d77-f156-324b3442cbe7@linaro.org> <114c357f8d7f049d21ede789a292a8e2d45f4c61.camel@mediatek.com> <0a82842d-283c-e266-84f4-6306f29b61da@linaro.org> X-Mailer: Evolution 3.28.5-0ubuntu0.18.04.2 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220830_200628_771214_04B17F0E X-CRM114-Status: GOOD ( 25.41 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, 2022-08-30 at 13:08 +0300, Krzysztof Kozlowski wrote: > On 29/08/2022 05:37, Chunfeng Yun wrote: > > On Fri, 2022-08-26 at 09:36 +0300, Krzysztof Kozlowski wrote: > > > On 26/08/2022 08:36, Chunfeng Yun wrote: > > > > On Tue, 2022-08-23 at 13:24 +0300, Krzysztof Kozlowski wrote: > > > > > On 22/08/2022 10:07, Chunfeng Yun wrote: > > > > > > On Fri, 2022-08-19 at 15:15 +0300, Krzysztof Kozlowski > > > > > > wrote: > > > > > > > On 19/08/2022 12:13, Chunfeng Yun wrote: > > > > > > > > Add a property to set usb2 phy's pre-emphasis. > > > > > > > > > > > > > > > > Signed-off-by: Chunfeng Yun > > > > > > > > --- > > > > > > > > Documentation/devicetree/bindings/phy/mediatek,tphy.ya > > > > > > > > ml | > > > > > > > > 7 > > > > > > > > +++++++ > > > > > > > > 1 file changed, 7 insertions(+) > > > > > > > > > > > > > > > > diff --git > > > > > > > > a/Documentation/devicetree/bindings/phy/mediatek,tphy.y > > > > > > > > aml > > > > > > > > b/Documentation/devicetree/bindings/phy/mediatek,tphy.y > > > > > > > > aml > > > > > > > > index 848edfb1f677..aee2f3027371 100644 > > > > > > > > --- > > > > > > > > a/Documentation/devicetree/bindings/phy/mediatek,tphy.y > > > > > > > > aml > > > > > > > > +++ > > > > > > > > b/Documentation/devicetree/bindings/phy/mediatek,tphy.y > > > > > > > > aml > > > > > > > > @@ -219,6 +219,13 @@ patternProperties: > > > > > > > > minimum: 1 > > > > > > > > maximum: 15 > > > > > > > > > > > > > > > > + mediatek,pre-emphasis: > > > > > > > > + description: > > > > > > > > + The selection of pre-emphasis (U2 phy) > > > > > > > > + $ref: /schemas/types.yaml#/definitions/uint32 > > > > > > > > + minimum: 1 > > > > > > > > + maximum: 3 > > > > > > > > > > > > > > Instead of hard-coding register values in bindings, you > > > > > > > should > > > > > > > rather > > > > > > > describe here feature/effect. If it is in units, use unit > > > > > > > suffixes. > > > > > > > If > > > > > > > it is some choice, usually string enum is appropriate. > > > > > > > > > > > > How about changing description as bellow: > > > > > > > > > > > > "The level of pre-emphasis, increases one level, boosts the > > > > > > relative > > > > > > amplitudes of signal's higher frequencies components about > > > > > > 4.16% > > > > > > (U2 > > > > > > phy)" > > > > > > > > > > > > > > > > Still the question is what is the unit. 4.16%? > > > > > > > > No unit, it's a level value, like an index of array. > > > > > > > > > > So a value from register/device programming? > > > > Yes > > > Rather a regular units > > > should be used if that's possible. If not, this should be clearly > > > described here, not some magical number which you encode into > > > DTS... > > > > Ok, I'll add more descriptions. > > Better use logical value, e.g. > https://urldefense.com/v3/__https://github.com/devicetree-org/dt-schema/blob/main/dtschema/schemas/property-units.yaml*L38__;Iw!!CTRNKA9wMg0ARbw!1e-h0R_uwcaHKfKC9qYfaRWYeuWRq1sLCGy3yupNmkFyuW5s1nmRotL7Y0vFG9ETLLTA$ > Optional unit may be -percent or -bp, but the value 4.16% * X (X=1,2,3...)is not an exact value, they are variable in a range and dependent more factors. So I think use level value is simple enough. > > Best regards, > Krzysztof _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel