From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-lj1-f171.google.com (mail-lj1-f171.google.com [209.85.208.171]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BC4B23B3C08 for ; Fri, 15 May 2026 14:38:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.171 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778855888; cv=none; b=SR6/3kkLVkqaa5qWYVXdYF2dkK5tX/8OoApDac8ZnjhwKmaC15AlAAy3vZ7D19YpSSZZ6R/zJV3n1seGBbNPnigoNBJqor/ZbkT85fBepfjv/lhsPck7n4NqaV3/KGOgv5qX/SH42PQKvMSzAxEhL6gXNlAdWXKsRpP9OqQETdA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778855888; c=relaxed/simple; bh=Q6eQ/PnI/4lNyvGcIep9mTKMWp0lV6GD0D36jxEkonc=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=XGMWtQQz2VDhVAe0vOnEyqICZbKK0xOBVZb6dJzgIIQr8v//7RADEgcu7QJl09STkuawr78cDt9QM7Fjoq3HA/hLl1c9Txn5XK4QAcGMxTAHaCQLrnj6xzYmy7GgVCMwEQT8xFB02Zo11pSR97qDSuHkL4WuBeAAqCsN6kUesvg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=iP5J883d; arc=none smtp.client-ip=209.85.208.171 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="iP5J883d" Received: by mail-lj1-f171.google.com with SMTP id 38308e7fff4ca-39396f873adso123377671fa.3 for ; Fri, 15 May 2026 07:38:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1778855885; x=1779460685; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=StZsbJeEJPo8M4uDdGQIgmZ75YI487IGeU37Pfexsek=; b=iP5J883d5YYYhZL3nq5nYkF82R8K4aq9dVpsDv+Uzcl2ucWsdmVD15/z/a+R1Dtk/I T6qTSt/mDC5mtdGeox4rVUwIDcjCQNs4LvzgyxkFdIB332GX8nppZG5d9bR0Bt7XAkjN /AN3rgSprHLTgiAPJ2iUZhX6YssvtzghIRGFdFbKazM/iV+Zo0csgvrxlSEDkpvQL9Li F52CLPLIHdmvvQfR77ucXscGnIkKCEXfJorXNUEmHfzj9+QgzJFMR8HmV4ZbJP9OSRod 0l4cbYk5OwgETArKyE8rr2zgmlKzXaiaQtlswOgQ+wx8tKW8ob+ADY7r74FwxJAQ5ReI z/HA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1778855885; x=1779460685; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=StZsbJeEJPo8M4uDdGQIgmZ75YI487IGeU37Pfexsek=; b=NgxPvjvNSXVCbeYfoeMKzhGDVXXAZq+7s2aXG38qYuZKaiaKtaOvNLHh2l9Z7L8ypm TObg0jK33Rxjd+urZB9ofztk7BkodpN8pQhtYfvbbsckW9PRNswku6/nagkIRUFg6IbI LPw2X3mkqnTJRUUNt11+NOgFze+tyc77p/urkLrXDpzzuBLdoiXWorbrOiUNEVq6cs7L eEPdhz/HF2NlDbVvl4TEMeRdja3KRgtM1YkFWsne4KVDhGMv6/Q9lcw6cg0ynzDHpWi2 p43aSHurtm4cyuj6z2VOkiWmx0fzfpDH+0BBUy5YhSQk1CJ/fRaI02PMgUT9qdrxQ1+d r4GA== X-Forwarded-Encrypted: i=1; AFNElJ/897hKJRQpiqi4WDOpPl6t/qUpsuIv8155Y45sLlR4PuH2vQ7TzEq0bKPfW2pdk6hJGSTY3ISpRPId@vger.kernel.org X-Gm-Message-State: AOJu0Yx5oFrySmyhpsf2mvuqjX52BIYWjlTX/9byIO8Vhb6qOnFZZFWK a5satdCRnvj3FlewQFWwZq/R16YExo4i6ERUwm3bumJzdASqPhJFq0To X-Gm-Gg: Acq92OFLt0FM9UqJolHNzPluv1AeQHn8bSarFYWVVDkvYw21e5T5zXPa+XebIx38DsD OhS4y0jqRvdJKWSaE8HlSPJieWqGVe4e4zrrhFDAeK09VRw48RJ06FFkzbWkcjf2vBJ39xsF0BE PCGmG3NFS4QmkGAGGv4NiZWcNCIxloqVv7ByeUtRHVNgaBbgWHShD4sEaT3q4MERaUmUwIt+TOW 0SuLCOy4ieVXwNhLhcCoXacdv0YnGSh6OpU/CIlE+ag9r+QVAeATCpA99EZ+IvtsLHlfYLwo3AW SvcTL+tcspmVJ3Om81uZMElneNNS/TCXyo33VwC1pjAxputdq9JhNg/Sx45WwUsU2Xh9W8BY9ml 1xKXaQ5bMUlCajPn8mlMmhOga/i0cECBj/xixjqoZ4zok22DXBmf4eDVGVC6QXQgJ6cUc/8N7MR BZpY0hMhxQO6kvK6kYMH0WFE3mZkUfRksEmJj4msynAzRRfe+EmFOkWc4= X-Received: by 2002:a05:6512:3a8f:b0:5a8:86a8:2e09 with SMTP id 2adb3069b0e04-5aa0e733fcdmr1252639e87.7.1778855884497; Fri, 15 May 2026 07:38:04 -0700 (PDT) Received: from qwas-jet.office.tvip.ru ([188.227.12.10]) by smtp.gmail.com with ESMTPSA id 38308e7fff4ca-3945cb38061sm15539511fa.37.2026.05.15.07.38.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 15 May 2026 07:38:04 -0700 (PDT) From: Nikita Maslo To: Bartosz Golaszewski , Linus Walleij Cc: Nikita Maslo , linux-gpio@vger.kernel.org, linux-amlogic@lists.infradead.org Subject: Broken bitbang 1-wire on Amlogic after kernel update Date: Fri, 15 May 2026 17:38:00 +0300 Message-ID: <20260515143801.2132974-1-nikitamalco203@gmail.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi, I was running linux-6.12.67 on a hardkernel odroid-c2 (Amlogic S905) Amlogic board with DS18B20 on w1-gpio (1-Wire bitbang), everything worked fine. After updating the kernel, 1-wire stopped working the DS18B20 fails to enumerate or reads back the broken-bus, and dmesg gets flooded with WARNINGs from gpiod_set_value/gpiod_get_value called from w1_gpio_write_bit/w1_gpio_read_bit. Hardware: Hardkernel ODROID-C2 (Amlogic S905). Kernel: linux-6.18.15 (also reproduces on linux-6.12.69; last known-good for me was linux-6.12.67). Device tree fragment used: / { onewire { compatible = "w1-gpio"; gpios = <&gpio GPIOX_17 GPIO_ACTIVE_HIGH>; }; }; dmesg, captured on ODROID-C2 / linux-6.18.15: [ 59.102855] ------------[ cut here ]------------ [ 59.102891] WARNING: CPU: 0 PID: 1145 at drivers/gpio/gpiolib.c:3880 gpiod_set_value+0x78/0x88 [ 59.103569] CPU: 0 UID: 0 PID: 1145 Comm: w1_bus_master1 Tainted: G WC 6.18.15-current-meson64 #8 PREEMPT [ 59.103618] Hardware name: Hardkernel ODROID-C2 (DT) [ 59.103658] pc : gpiod_set_value+0x78/0x88 [ 59.103687] lr : w1_gpio_write_bit+0x20/0x38 [w1_gpio] [ 59.104161] Call trace: [ 59.104175] gpiod_set_value+0x78/0x88 (P) [ 59.104210] w1_gpio_write_bit+0x20/0x38 [w1_gpio] [ 59.104238] w1_reset_bus+0x84/0xe0 [wire] [ 59.104272] w1_search+0x88/0x2a0 [wire] [ 59.104304] w1_search_devices+0x54/0x90 [wire] [ 59.104336] w1_search_process_cb+0x84/0x170 [wire] [ 59.104368] w1_process+0x1c0/0x238 [wire] [ 59.104400] kthread+0x14c/0x218 [ 59.104432] ret_from_fork+0x10/0x20 [ 59.104464] ---[ end trace 0000000000000000 ]--- A symmetric WARN at gpiolib.c:3501 fires from gpiod_get_value via w1_gpio_read_bit on every read slot. After a little researching, the suspect commit looks like: 28f240683871 ("pinctrl: meson: mark the GPIO controller as sleeping") I also tested bitbang i2c-gpio on the same hardware after the update, it seems to keep working.