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 A4284CCA48E for ; Tue, 26 Jul 2022 07:24:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238353AbiGZHYQ (ORCPT ); Tue, 26 Jul 2022 03:24:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58256 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238119AbiGZHXa (ORCPT ); Tue, 26 Jul 2022 03:23:30 -0400 Received: from mail-ej1-x62d.google.com (mail-ej1-x62d.google.com [IPv6:2a00:1450:4864:20::62d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A9B4D2B622 for ; Tue, 26 Jul 2022 00:23:21 -0700 (PDT) Received: by mail-ej1-x62d.google.com with SMTP id ez10so24418320ejc.13 for ; Tue, 26 Jul 2022 00:23:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=DD0uadPhkaJ539aapAhTDeVFQH+XGwCWm7G+YfPh7fc=; b=Kba4ZDV1A/AXRgz6iEbxRwn8EqVTv2R9yv+8Q2gRza9+ZIvQtXmDpHMJ+sUhFJFMZ0 7FbNc6d3/UoKdDqyTR5suL8w6TJ5Gn4/Kz3AtA2NjJTGAKHlcxyL3aJx4A7+/5TiUfQS NxlzBAykIrKayHvDFOAKgU5Tiinpei2lR44V3d7wEJl+WEyIYRuRvQ9iG/c5gF30k3Zl UFz7H/aJUp9D6Vjh3W9yMy72PrQ2Xxh5RoEOE3cP+U8zGqLPIIyi1AHwfcGI0gIcwimM 2dsoyOJLHp+5tVE6zpTC3LAoEK7Uku2f0P0wNfD7NWfh2JBiJ8ColgXgz/u4zr4EIrTZ 1Fsw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=DD0uadPhkaJ539aapAhTDeVFQH+XGwCWm7G+YfPh7fc=; b=NGo8vVTiOwccjc/bWwdZJ3knuUov/hj7bYxmgG5bCb0zC6e5trtj2Xn+GDM6ZtzywK +3rxItoD2ychf64C/mT4PueYM6ie5yEfcU+5y8A5ApyeWwB4wdFigxQfHXtm2XX4qYye nTzUOohZVyReeZeWSsrX3YdnUkUU0pYv+LDzY4FsOzXgkCFjbH0beEhTc3bFN07k5Ylb qAo/KusU8S0m05LQ7yKZy8SiRuzxwJT7jrtrwxIrkI1D4evzp1taWIF0pAbsSfuvZee0 6vEvJQH8YvEq8QMmUS9Z8epagCL4u/mc87tg5h63HwNxBDojA413NETzyVnjorlte2h6 ySGQ== X-Gm-Message-State: AJIora+2NDPBjrvelOfMJVsOfGrL9ScA9Xza0y9zSg678vWY7M4biXlI 7Z26FMjxpIBqj4SkniEiJQyxCK7zvOl+ybMzRgXyIg== X-Google-Smtp-Source: AGRyM1tNXCKI2buHcvEhsS4ymiRcgoitpKwhQicSRzpI9ca8De/k6MNUhY31qEeF7NOfuZPg6YuHDk4sc/waM5l8O4g= X-Received: by 2002:a17:906:58c8:b0:6fe:91d5:18d2 with SMTP id e8-20020a17090658c800b006fe91d518d2mr13217132ejs.190.1658820199862; Tue, 26 Jul 2022 00:23:19 -0700 (PDT) MIME-Version: 1.0 References: <20220721093422.2173982-1-marcus.folkesson@gmail.com> In-Reply-To: From: Linus Walleij Date: Tue, 26 Jul 2022 09:23:08 +0200 Message-ID: Subject: Re: [PATCH 1/2] gpio: gpio-74x164: add support for CDx4HC4094 To: Andy Shevchenko Cc: Marcus Folkesson , Bartosz Golaszewski , Rob Herring , Krzysztof Kozlowski , Maxime Ripard , "open list:GPIO SUBSYSTEM" , devicetree , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Tue, Jul 26, 2022 at 8:55 AM Andy Shevchenko wrote: > On Tue, Jul 26, 2022 at 12:22 AM Linus Walleij wrote: > > Well it will work, because all values come out, however *during* > > the transfer, not *after* the transfer as intended with the > > STR signal. > > No. I think you missed one little but crucial detail. The strobe is > edge, not level, while you consider CS as a level signal (only). Aha! Then it works :) > See Figure 7 and Table 9 in the datasheet you linked to. When STR is > low, the data is not changed. Maybe it's not clear in this datasheet, > I found somewhere > in a more clear table. > > > At least how I see it ...? > > If what you are saying is true, the hardware is totally broken and I > wouldn't use it. I.o.w. if the strobe passes all data when it's at low > level and latches at low-to-high, it's broken by definition in my > point of view. I have seen strobes that are level-active in my life, but if you say this one isn't then all is fine! Yours, Linus Walleij