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 DCA3FCE7A81 for ; Mon, 25 Sep 2023 13:22:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231747AbjIYNWK (ORCPT ); Mon, 25 Sep 2023 09:22:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40862 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230445AbjIYNWH (ORCPT ); Mon, 25 Sep 2023 09:22:07 -0400 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E735EA2; Mon, 25 Sep 2023 06:22:00 -0700 (PDT) Received: from lhrpeml500005.china.huawei.com (unknown [172.18.147.206]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4RvNl16n7cz6D9y0; Mon, 25 Sep 2023 21:19:41 +0800 (CST) Received: from localhost (10.202.227.76) by lhrpeml500005.china.huawei.com (7.191.163.240) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Mon, 25 Sep 2023 14:21:58 +0100 Date: Mon, 25 Sep 2023 14:21:57 +0100 From: Jonathan Cameron To: Krzysztof Kozlowski CC: Andreas Kemnade , , , , , , , , , , , , , , Subject: Re: [PATCH 1/3] dt-bindings: iio: imu: mpu6050: Add level shifter Message-ID: <20230925142157.00000914@Huawei.com> In-Reply-To: <3b81a9a7-69a3-4fd6-875f-7a5170c5c872@linaro.org> References: <20230924222559.2038721-1-andreas@kemnade.info> <20230924222559.2038721-2-andreas@kemnade.info> <6db5b758-2ae6-46fb-a699-d73a2b98b4c2@linaro.org> <20230925112852.00007d34@Huawei.com> <20230925130225.55fe6fd4@aktux> <3b81a9a7-69a3-4fd6-875f-7a5170c5c872@linaro.org> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.1.0 (GTK 3.24.33; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.202.227.76] X-ClientProxiedBy: lhrpeml500003.china.huawei.com (7.191.162.67) To lhrpeml500005.china.huawei.com (7.191.163.240) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 25 Sep 2023 14:24:32 +0200 Krzysztof Kozlowski wrote: > On 25/09/2023 13:02, Andreas Kemnade wrote: > > On Mon, 25 Sep 2023 11:28:52 +0100 > > Jonathan Cameron wrote: > > > >> On Mon, 25 Sep 2023 08:54:08 +0200 > >> Krzysztof Kozlowski wrote: > >> > >>> On 25/09/2023 00:25, Andreas Kemnade wrote: > >>>> Found in ancient platform data struct: > >>>> level_shifter: 0: VLogic, 1: VDD > >>>> > >>>> Signed-off-by: Andreas Kemnade > >>>> --- > >>>> .../devicetree/bindings/iio/imu/invensense,mpu6050.yaml | 2 ++ > >>>> 1 file changed, 2 insertions(+) > >>>> > >>>> diff --git a/Documentation/devicetree/bindings/iio/imu/invensense,mpu6050.yaml b/Documentation/devicetree/bindings/iio/imu/invensense,mpu6050.yaml > >>>> index 1db6952ddca5e..6aae2272fa15c 100644 > >>>> --- a/Documentation/devicetree/bindings/iio/imu/invensense,mpu6050.yaml > >>>> +++ b/Documentation/devicetree/bindings/iio/imu/invensense,mpu6050.yaml > >>>> @@ -48,6 +48,8 @@ properties: > >>>> > >>>> mount-matrix: true > >>>> > >>>> + invensense,level-shifter: true > >>> > >>> It does not look like you tested the bindings, at least after quick > >>> look. Please run `make dt_binding_check` (see > >>> Documentation/devicetree/bindings/writing-schema.rst for instructions). > >>> Maybe you need to update your dtschema and yamllint. > >>> > >>> Best regards, > >>> Krzysztof > >>> > >>> > >> > >> Also this one isn't obvious - give it a description in the binding doc. > >> > >> I'm not sure of the arguement for calling it level shift in general. > >> > > I have no more descrption than the old source (see the citation from there) > > https://invensense.tdk.com/wp-content/uploads/2015/02/MPU-9150-Register-Map.pdf > > I could not find any reference to level shift in this manual. To which > page and part do you refer? > > > > > does not list it. But that bit is needed to get things to work what also does the > > vendor kernel do. > > > > What could be a better descrption? > > I don't know, but something reasonable to you should be put there. The text you have in the commit log seems better than nothing. I suspect it's internally wiring VDD to VDDIO. Normally people just connect both power supplies to same supply if they want to do that, but maybe there was a chip variant that didn't have enough pins? If you have the device, can you see it actually matches the packaging types in the manual? Jonathan > > Best regards, > Krzysztof > >