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{ "id": 2227570, "url": "http://patchwork.ozlabs.org/api/covers/2227570/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-gpio/cover/20260423230338.442497-1-bigunclemax@gmail.com/", "project": { "id": 42, "url": "http://patchwork.ozlabs.org/api/projects/42/?format=api", "name": "Linux GPIO development", "link_name": "linux-gpio", "list_id": "linux-gpio.vger.kernel.org", "list_email": "linux-gpio@vger.kernel.org", "web_url": "", "scm_url": "", "webscm_url": "", "list_archive_url": "", "list_archive_url_format": "", "commit_url_format": "" }, "msgid": "<20260423230338.442497-1-bigunclemax@gmail.com>", "list_archive_url": null, "date": "2026-04-23T23:03:34", "name": "[RFC,0/1] reset: gpio: Add support for GPIO providers with #gpio-cells=3", "submitter": { "id": 78282, "url": "http://patchwork.ozlabs.org/api/people/78282/?format=api", "name": "Maxim Kiselev", "email": "bigunclemax@gmail.com" }, "mbox": "http://patchwork.ozlabs.org/project/linux-gpio/cover/20260423230338.442497-1-bigunclemax@gmail.com/mbox/", "series": [ { "id": 501262, "url": "http://patchwork.ozlabs.org/api/series/501262/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-gpio/list/?series=501262", "date": "2026-04-23T23:03:34", "name": "reset: gpio: Add support for GPIO providers with #gpio-cells=3", "version": 1, "mbox": "http://patchwork.ozlabs.org/series/501262/mbox/" } ], "comments": "http://patchwork.ozlabs.org/api/covers/2227570/comments/", "headers": { "Return-Path": "\n <linux-gpio+bounces-35442-incoming=patchwork.ozlabs.org@vger.kernel.org>", "X-Original-To": [ "incoming@patchwork.ozlabs.org", "linux-gpio@vger.kernel.org" ], "Delivered-To": "patchwork-incoming@legolas.ozlabs.org", "Authentication-Results": [ "legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256\n header.s=20251104 header.b=Z4OgTslK;\n\tdkim-atps=neutral", "legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2600:3c0a:e001:db::12fc:5321; helo=sea.lore.kernel.org;\n envelope-from=linux-gpio+bounces-35442-incoming=patchwork.ozlabs.org@vger.kernel.org;\n receiver=patchwork.ozlabs.org)", "smtp.subspace.kernel.org;\n\tdkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com\n header.b=\"Z4OgTslK\"", "smtp.subspace.kernel.org;\n arc=none smtp.client-ip=209.85.167.44", "smtp.subspace.kernel.org;\n dmarc=pass (p=none dis=none) header.from=gmail.com", "smtp.subspace.kernel.org;\n spf=pass smtp.mailfrom=gmail.com" ], "Received": [ "from sea.lore.kernel.org (sea.lore.kernel.org\n [IPv6:2600:3c0a:e001:db::12fc:5321])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange x25519 server-signature ECDSA (secp384r1) server-digest SHA384)\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4g1s9y57Xnz1yDD\n\tfor <incoming@patchwork.ozlabs.org>; Fri, 24 Apr 2026 09:04:54 +1000 (AEST)", "from smtp.subspace.kernel.org (conduit.subspace.kernel.org\n [100.90.174.1])\n\tby sea.lore.kernel.org (Postfix) with ESMTP id EE13E302D088\n\tfor <incoming@patchwork.ozlabs.org>; Thu, 23 Apr 2026 23:04:29 +0000 (UTC)", "from localhost.localdomain (localhost.localdomain [127.0.0.1])\n\tby smtp.subspace.kernel.org (Postfix) with ESMTP id 982C63D8119;\n\tThu, 23 Apr 2026 23:04:29 +0000 (UTC)", "from mail-lf1-f44.google.com (mail-lf1-f44.google.com\n [209.85.167.44])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits))\n\t(No client certificate requested)\n\tby smtp.subspace.kernel.org (Postfix) with ESMTPS id A82EF3D8122\n\tfor <linux-gpio@vger.kernel.org>; Thu, 23 Apr 2026 23:04:27 +0000 (UTC)", "by mail-lf1-f44.google.com with SMTP id\n 2adb3069b0e04-5a3fcb2c718so6149979e87.0\n for <linux-gpio@vger.kernel.org>;\n Thu, 23 Apr 2026 16:04:27 -0700 (PDT)", "from wpc (host-95-152-45-178.dsl.sura.ru. 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charset=UTF-8", "Content-Transfer-Encoding": "8bit" }, "content": "From: Maksim Kiselev <bigunclemax@gmail.com>\n\nHello everyone,\n\nA little background.\nI have a BigTreeTech CB1 board based on the Allwinner H616.\nI decided to try upstream Linux v7.0 and ran into the following issue:\n\n[ 0.453297] pwrseq_simple wifi-pwrseq: error -ENOENT: reset control not ready\n[ 0.460472] pwrseq_simple wifi-pwrseq: probe with driver pwrseq_simple failed with error -2\n\nThis error prevents the WiFi chip from coming up.\n\nI started investigating and traced it down to the function\n__reset_add_reset_gpio_device() in drivers/reset/core.c:\n\n/*\n * @args:\tphandle to the GPIO provider with all the args like GPIO number\n */\nstatic int __reset_add_reset_gpio_device(const struct of_phandle_args *args)\n{\n\tstruct property_entry properties[3] = { };\n\tunsigned int offset, of_flags, lflags;\n\tstruct reset_gpio_lookup *rgpio_dev;\n\tstruct device *parent;\n\tint id, ret, prop = 0;\n\n\t/*\n\t * Currently only #gpio-cells=2 is supported with the meaning of:\n\t * args[0]: GPIO number\n\t * args[1]: GPIO flags\n\t * TODO: Handle other cases.\n\t */\n\tif (args->args_count != 2)\n\t\treturn -ENOENT;\n\nAs you can see, a GPIO from controller where #gpio-cells != 2 will cause\nan error.\n\nUnfortunately, the Allwinner pinctrl is one such GPIO controller.\nIt uses three arguments to describe a GPIO line: bank, number, and flags.\n\nHere’s the DT fragment that describes wifi_pwrseq in\narch/arm64/boot/dts/allwinner/sun50i-h616-bigtreetech-cb1.dtsi file:\n\nwifi_pwrseq: wifi-pwrseq {\n\tcompatible = \"mmc-pwrseq-simple\";\n\tclocks = <&rtc 1>;\n\tclock-names = \"ext_clock\";\n\treset-gpios = <&pio 6 18 GPIO_ACTIVE_LOW>; /* PG18 */\n\tpost-power-on-delay-ms = <200>;\n};\n\nPotentially this problem could also be observed on other GPIO controllers:\nspacemit,k1-gpio, microchip,sparx5-sgpio, and many allwinner,___-pinctrl\nvariants.\n\nI attempted to make a patch for reset/core.c (not pretty in my opinion)\nthat adds support for three-args GPIO phandles.\nBut it seems I’ve fallen down a rabbit hole, because next I hit the fact\nthat gpiolib-swnode expects GPIOs to be described with exactly\ntwo arguments (swnode_gpio_get_reference()).\n\nI also did a git bisect to find when wifi_pwrseq broke for\nthe BigTreeTech CB1. It turned out to be commit\n73bf4b7381f7 (\"mmc: pwrseq_simple: add support for one reset control\")\nin v6.13-rc1.\n\nSo, in theory, a patch to pwrseq_simple.c could be made to fix my issue,\nbut that wouldn’t solve the underlying reset-gpio problem.\n\nI don’t know how to proceed from here and I’m asking for advice.\n\nBest regards\nMaksim\n\nMaksim Kiselev (1):\n reset: add support the GPIO provider with #gpio-cells=3\n\n drivers/reset/core.c | 33 +++++++++++++++++++++++----------\n 1 file changed, 23 insertions(+), 10 deletions(-)" }