[{"id":1770085,"web_url":"http://patchwork.ozlabs.org/comment/1770085/","msgid":"","list_archive_url":null,"date":"2017-09-18T11:15:55","subject":"Re: [PATCH 0/7] I2C GPIO to use gpiolibs open drain","submitter":{"id":703,"url":"http://patchwork.ozlabs.org/api/people/703/","name":"Geert Uytterhoeven","email":"geert@linux-m68k.org"},"content":"Hi Linus,\n\nOn Sun, Sep 17, 2017 at 11:38 AM, Linus Walleij\n wrote:\n> This augments the I2C GPIO driver to use open drain emulation\n> or hardware support for open drain from the GPIO driver.\n>\n> This version layers Geert Uytterhoeven's idea to use explicit\n> sda-gpios and scl-gpios for the GPIO lines, and strongly\n> encourage the (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN) flags to be\n> used in all device trees.\n>\n> We have collected ACKs from the ARM SoC maintainers and the\n> MFD maintainer and are looking for testers to try this out.\n>\n> Geert Uytterhoeven (1):\n> dt-bindings: i2c: i2c-gpio: Add support for named gpios\n>\n> Linus Walleij (6):\n> i2c: gpio: Convert to use descriptors\n> gpio: Make it possible for consumers to enforce open drain\n> i2c: gpio: Enforce open drain through gpiolib\n> i2c: gpio: Augment all boardfiles to use open drain\n> i2c: gpio: Local vars in probe\n> i2c: gpio: Add support for named gpios in DT\n\nThanks for doing this, and picking up my patch.\n\nI gave this a try on r8a7740/armadillo800eva.\nWithout DT changes, the GPIO i2c bus still works fine, but a warning is\nprinted, as expected:\n\n gpio-208 (sda): enforced open drain please flag it properly in\nDT/ACPI DSDT/board file\n gpio-91 (scl): enforced open drain please flag it properly in\nDT/ACPI DSDT/board file\n\nAfter\n\n - sda-gpios = <&pfc 208 GPIO_ACTIVE_HIGH>;\n - scl-gpios = <&pfc 91 GPIO_ACTIVE_HIGH>;\n + sda-gpios = <&pfc 208 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;\n + scl-gpios = <&pfc 91 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;\n\nthe warning is gone, and the GPIO i2c bus still works.\n\nTested-by: Geert Uytterhoeven \n\nGr{oetje,eeting}s,\n\n Geert\n\n--\nGeert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org\n\nIn personal conversations with technical people, I call myself a hacker. But\nwhen I'm talking to journalists I just say \"programmer\" or something like that.\n -- Linus Torvalds","headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@bilbo.ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=linux-i2c-owner@vger.kernel.org;\n\treceiver=)","ozlabs.org;\n\tdkim=fail reason=\"signature verification failed\" (2048-bit key;\n\tunprotected) header.d=gmail.com header.i=@gmail.com\n\theader.b=\"DmgLIkaD\"; dkim-atps=neutral"],"Received":["from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xwk2k4JXQz9s7G\n\tfor ;\n\tMon, 18 Sep 2017 21:15:58 +1000 (AEST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1752600AbdIRLP5 (ORCPT );\n\tMon, 18 Sep 2017 07:15:57 -0400","from mail-pg0-f68.google.com ([74.125.83.68]:34342 \"EHLO\n\tmail-pg0-f68.google.com\" rhost-flags-OK-OK-OK-OK) by vger.kernel.org\n\twith ESMTP id S1752156AbdIRLP4 (ORCPT\n\t); Mon, 18 Sep 2017 07:15:56 -0400","by mail-pg0-f68.google.com with SMTP id v82so79613pgb.1\n\tfor ; Mon, 18 Sep 2017 04:15:56 -0700 (PDT)","by 10.100.160.13 with HTTP; Mon, 18 Sep 2017 04:15:55 -0700 (PDT)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=gmail.com; s=20161025;\n\th=mime-version:sender:in-reply-to:references:from:date:message-id\n\t:subject:to:cc;\n\tbh=4ve3tJQ3ZQkrSAlPYgR/EAUoghZeu+Wb6CReR/d+Rrk=;\n\tb=DmgLIkaD4TMwV3/efg/M4pw1CbvEJbvyl6P3hRWd2r2psBaXTTfl0KsA54JhnMY1LF\n\tFka3JBlPsB3mzpcAPvw9YFixaJ9f72yJXPHKawVdyO2ALWsC262MnuHa2s3dvnt4SNhI\n\t69ifpDyPW3iBhWhiWDDdagir26nKDQiW/L8amhC3fNNuuOlIVgR5bneaWbXjCGrUIDll\n\tJ8qdj063SD/Mgwb9DcKZnQYp94ifxdI6br898W1kXJUP3wI9JABXXwP1qQTxR1p42jBY\n\tMlCuihDB4LKdI4ZtfOl6TIu17mlPRtnGIixhREAKdmP1h6WA0iZZK0UCcDVDTF3+8mhd\n\tjQGQ==","X-Google-DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=1e100.net; s=20161025;\n\th=x-gm-message-state:mime-version:sender:in-reply-to:references:from\n\t:date:message-id:subject:to:cc;\n\tbh=4ve3tJQ3ZQkrSAlPYgR/EAUoghZeu+Wb6CReR/d+Rrk=;\n\tb=KSxx3tJo20yA8eWDWyRf+JakBmFOP3lQBh6JzGFsezkTr7PCp40tyn4sx1VfegGhxe\n\tuv/1EB+HpeLBul2/EseltEgDkJN0v5dT5+cB5q580/aR3bMWukBn6o9lRgqpZovK1irk\n\th1AYvO7UpTzXKdB/r9lxh8gqMkU8zIsUsDzQUpPN+weGMwdpvsLjsesf58hGOShHHqZG\n\t8oOSPwmnb24H8i9IeX2SksVbv4++hlO3OEEPKCyh2c9qK4sCdQQw2ATO0e+73O6E5ufG\n\t28C89FvrRZleetnTk6lE+Ka0UQg3jt/dvU8PxeSTyHYvV3vW9QOCmoP8vqePzIoS+i1b\n\tZmJA==","X-Gm-Message-State":"AHPjjUhAgScD1wwlPibhjiPfNFOabuV2T31xKrYJ9Oyqr5W5/ydn4D2x\n\tP+yzbKjxNdIA89PkzRRSfbtd+DDJxBfjs5p1ehw=","X-Google-Smtp-Source":"ADKCNb6+nMLeLv25YFbinFmW+WYOhpnln4w9YakSBQ2sTRmYK8heP4+lM1D3+mjouyA89KBpV7UI9D6GcV5bPXSTRRk=","X-Received":"by 10.98.217.75 with SMTP id s72mr31474346pfg.158.1505733356089; \n\tMon, 18 Sep 2017 04:15:56 -0700 (PDT)","MIME-Version":"1.0","In-Reply-To":"<20170917093906.16325-1-linus.walleij@linaro.org>","References":"<20170917093906.16325-1-linus.walleij@linaro.org>","From":"Geert Uytterhoeven ","Date":"Mon, 18 Sep 2017 13:15:55 +0200","X-Google-Sender-Auth":"Dj9C1qSWPrBO8jZisOIGx-ICcls","Message-ID":"","Subject":"Re: [PATCH 0/7] I2C GPIO to use gpiolibs open drain","To":"Linus Walleij ","Cc":"Wolfram Sang , Linux I2C ,\n\t\"linux-arm-kernel@lists.infradead.org\" \n\t,\n\tLinux MIPS Mailing List ,\n\t\"adi-buildroot-devel@lists.sourceforge.net\" \n\t","Content-Type":"text/plain; charset=\"UTF-8\"","Sender":"linux-i2c-owner@vger.kernel.org","Precedence":"bulk","List-ID":"","X-Mailing-List":"linux-i2c@vger.kernel.org"}}]