Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752648AbdLFPET (ORCPT ); Wed, 6 Dec 2017 10:04:19 -0500 Received: from mail-lf0-f65.google.com ([209.85.215.65]:35960 "EHLO mail-lf0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752018AbdLFPEO (ORCPT ); Wed, 6 Dec 2017 10:04:14 -0500 X-Google-Smtp-Source: AGs4zMZsuQL96VTFvlAwrFOXnxzlmhsXIUYDcQv7BMnIFYzonyX29Hct+6k1lDRD0UbkeDIQ6kvXiSv25xAcjseetKM= MIME-Version: 1.0 In-Reply-To: <20171206135255.6990-1-poeschel@lemonage.de> References: <20171206135255.6990-1-poeschel@lemonage.de> From: Geert Uytterhoeven Date: Wed, 6 Dec 2017 16:04:10 +0100 X-Google-Sender-Auth: a2QQOHGQf55vZ7MtiiMJ354qYTE Message-ID: Subject: Re: [PATCH] video: hd44780: Add hd44780 lcd display driver To: Lars Poeschel Cc: David Airlie , Rob Herring , Mark Rutland , Bartlomiej Zolnierkiewicz , =?UTF-8?Q?Manuel_Sch=C3=B6lling?= , Greg Kroah-Hartman , Daniel Vetter , Stafford Horne , Christophe Leroy , Randy Dunlap , Kate Stewart , Philippe Ombredanne , Sean Paul , Thomas Gleixner , DRI Development , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Linux Fbdev development list Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1813 Lines: 51 Hi Lars, On Wed, Dec 6, 2017 at 2:52 PM, Lars Poeschel wrote: > This adds a console driver for hd44780 based character lcd displays and > clones. The driver currently supports 20x4 character displays with > character ROMs A00 and A02. > The hardware wirings to the display have to be supplied to the kernel in > the devicetree. The binding doc has the necessary information. > There are also tons of these cheap displays sold with a serial > interface. Many of them use a simple pcf8574 gpio expanders. An example > for using that kind of display is also in the binding doc. > > Signed-off-by: Lars Poeschel Thanks for your patch! > --- > .../bindings/video/console/hd44780con.txt | 42 ++ > drivers/video/console/Kconfig | 13 + > drivers/video/console/Makefile | 1 + > drivers/video/console/hd44780con.c | 676 +++++++++++++++++++++ I'm wondering if you could implement this on top of the existing charlcd framework: drivers/auxdisplay/charlcd.c include/misc/charlcd.h which can use the existing hd44780 backend: Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt drivers/auxdisplay/hd44780.c That way it can be used on other character LCDs, like the one supported by drivers/auxdisplay/panel.c. Thanks! P.S. I did something similar a long time ago, cfr. https://github.com/geertu/hd44780/blob/master/lcdcon.c Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds