Received: by 2002:a05:6a10:f347:0:0:0:0 with SMTP id d7csp724276pxu; Wed, 6 Jan 2021 02:40:21 -0800 (PST) X-Google-Smtp-Source: ABdhPJwQnUXkpXwY4XRFumtoXyxWLJFBCIcdzZahYldyUhxgB315LM/FCK1ZoSj9HyqajToLD3ko X-Received: by 2002:a17:906:705:: with SMTP id y5mr2349584ejb.428.1609929620916; Wed, 06 Jan 2021 02:40:20 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1609929620; cv=none; d=google.com; s=arc-20160816; b=MXyqMJIjr6xTGt/3n8mUpwXrCdnyxmAE1RlTo0qSk4ntRBuoXcicJJ9YI8bfFGdHvp 5BVdeyUU7+Y1jDHj28gBvSiAScSPGleASiFSS4GbsTKniD0+yms8yG5VgMdSaRbJNK+X Dw1V3eUABu/YCG36E86VYAnAnMdckg6qUnIu0O7gj9KSDiHkeNc9+i6r83/st7OsdAjG XP7VYLZwbm/qe70cmAqBXP5Ybo1Tcedr4qx4MyGYe3Bqna2wrt+J7DZTPHAo/tkNZvHC bRGz4Cawy+h/srznTHMFdtVEt9wFQm2X8XYI+b9+rQS1QWLFHu8PwP8nS5p8aFP4NaAP FkTQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:user-agent:in-reply-to:content-disposition :mime-version:references:message-id:subject:cc:to:from:date; bh=6y9ZojttwQWYmQheNkoH/sc16KAQult41jmPKhggQjQ=; b=DVc2M7WvkUrid/qzk+mNehAWIKoFxgIaGzfGIy/UgiKRB8MRvYfWSEhyCIup1p7ttT Ut0oRAeBmJ5QdXVWA2ufhOHyCxe+QzgZv7O4++f8hSRu109lTgk9332VgmZtWS9H/PVp 8495csg1KhkByAEH2XoIewIM6h8mzy82gB9XEhBXI941eDjC4paWK6cmqmSYLNRkkgcr VYhTURWVzst+vPjdhDyo3Sc9UTUFa/1jlddfnbDDwt5GJ+mql4S0AoK73m5tImUx+2/N OEkKD5vgXinE+lvQ9ADv7SRvGuLoM3N0C9w0bm9Rv/1eCfQB8u1tko7nVyskUgjGcLVp 1VAA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id q25si843763edw.87.2021.01.06.02.39.55; Wed, 06 Jan 2021 02:40:20 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726951AbhAFKiP (ORCPT + 99 others); Wed, 6 Jan 2021 05:38:15 -0500 Received: from tux.runtux.com ([176.9.82.136]:55426 "EHLO tux.runtux.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726195AbhAFKiP (ORCPT ); Wed, 6 Jan 2021 05:38:15 -0500 Received: from localhost (localhost [127.0.0.1]) by tux.runtux.com (Postfix) with ESMTP id 6D3206EF93; Wed, 6 Jan 2021 11:37:27 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at tux.runtux.com Received: from tux.runtux.com ([127.0.0.1]) by localhost (tux2.runtux.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id xqxNnamEXbMe; Wed, 6 Jan 2021 11:37:26 +0100 (CET) Received: from bee.priv.zoo (62-99-217-90.static.upcbusiness.at [62.99.217.90]) (Authenticated sender: postmaster@runtux.com) by tux.runtux.com (Postfix) with ESMTPSA id 61E166EEFF; Wed, 6 Jan 2021 11:37:26 +0100 (CET) Received: by bee.priv.zoo (Postfix, from userid 1002) id 750A346C; Wed, 6 Jan 2021 11:37:25 +0100 (CET) Date: Wed, 6 Jan 2021 11:37:25 +0100 From: Ralf Schlatterbeck To: Geert Uytterhoeven Cc: linux-kernel , Willy Tarreau , Lars Poeschel , Linus Walleij , Miguel Ojeda Subject: Re: [PATCH 1/2] auxdisplay: HD44780 connected to I2C via PCF8574 Message-ID: <20210106103725.vlqsmlxmqkjbyrzu@runtux.com> References: <20210105150124.dvlochv3qrp4wpre@runtux.com> <20210105150400.j7hhxu5uextga5mz@runtux.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-ray: beware User-Agent: NeoMutt/20180716 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Miguel, Geert, thanks for the quick feedback. On Wed, Jan 06, 2021 at 09:03:13AM +0100, Geert Uytterhoeven wrote: > > Unless I'm missing some little detail, there should be no need for this > driver: this wiring (and alternative wirings) can just be expressed in DT. > Examples (using 74HC595 SPI GPIO expanders) can be found in my > renesas-overlays branch: Thanks for the examples. I've tried this and it really works! It feels somewhat slower (I'm using user-defined characters) but that probably doesn't warrant its own driver. So I'll contribute a documentation change that adds an example of how to use the I2C-enabled version of the display, this may be non-obvious to others. I'll start a new thread for this, stay tuned... @Miguel: Thanks for your detailed feedback on coding style, I'll use this next time ;-) Ralf -- Ralf Schlatterbeck Tel: +43/2243/26465-16 Open Source Consulting www: www.runtux.com Reichergasse 131, A-3411 Weidling email: office@runtux.com