From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 886CE44AB91; Tue, 21 Jul 2026 21:35:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784669737; cv=none; b=NnwIAt5pLmITKtejB55KuIzV/w4O2j0byXmvV4e3ma7YTSmn9VFxzqieL1CCx2tQvL1UO4zwA1O7FJHcTGI//kf2lr9bHencrQ6O+55OPwfk9PDsFWp+nleSzOCevQg1rw+8thhru460HyQ+CpshoQwOGsZNxpJbQYzr5aD/xUk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784669737; c=relaxed/simple; bh=hl61Q6tY08VGxhSDbEDifQFlFQ2Dn8TMa3/lSwxK9bg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=oNxtgPqtv1wKijyUQYeWA/KoKk6GS8v+MqXobugxwezO5WMztcBAvy7NiaUqimXNuKnO9cq0uD+lnc70hcB/Lm45bcowg/VbFkIKBmTdq3bJrL28rDxwJ5fnhZFVd4rCPFE8dhPvpq5ZdUMSAzo+hfyDYKtqfNWGnGOTLJ2Y3FU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=I0yEreWL; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="I0yEreWL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A7CCD1F000E9; Tue, 21 Jul 2026 21:35:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784669735; bh=oc3vEdLs7uE2BP11yvZc7N31oomCDjHH2a+vtQgB2GQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=I0yEreWLilsuOQH4UVNpg9Z5YWevxfkYaUYLIEciLiRqQZ1wjrDhsbz3aRksvGmai k3vG6b2L17TSuEh7eOHUvPKpti4BTXV3hf6WLUSyQ6gURLPv+UwW6SMvmwB87qbsOK 65jhYsf5uKISPyO+Lr85aMo+miUADW/hTGpvJ6TU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Viacheslav Bocharov , Linus Walleij , Bartosz Golaszewski , Sasha Levin Subject: [PATCH 6.1 0668/1067] pinctrl: meson: restore non-sleeping GPIO access Date: Tue, 21 Jul 2026 17:21:09 +0200 Message-ID: <20260721152439.539617969@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152424.521567757@linuxfoundation.org> References: <20260721152424.521567757@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Viacheslav Bocharov [ Upstream commit 9777530157e7b82fd994327ff878c4245dadc931 ] Commit 28f240683871 ("pinctrl: meson: mark the GPIO controller as sleeping") set gpio_chip.can_sleep = true to work around gpio-shared-proxy holding a spinlock across a sleeping pinctrl config path. That locking bug is now fixed in the shared-proxy itself ("gpio: shared-proxy: always serialize with a sleeping mutex"), so the controller-wide workaround is no longer needed; the meson GPIO controller does not sleep. meson_gpio_get/set/direction_* access MMIO through regmap. The regmap_mmio bus uses fast I/O (spinlock) locking, so these value callbacks do not contain sleeping operations. Since gpio_chip.can_sleep describes the get/set value path, restore can_sleep = false. Marking the controller sleeping also broke atomic value consumers such as w1-gpio (1-Wire bitbang): w1_io.c runs its read time slot under local_irq_save() and uses the non-cansleep gpiod_set_value() / gpiod_get_value(), which with can_sleep=true trigger WARN_ON(can_sleep) in gpiolib on every transferred bit (from w1_gpio_write_bit() / w1_gpio_read_bit() via w1_reset_bus() and w1_search()). The printk and stack dump inside the IRQs-off, microsecond-scale time slot destroy the bit timing, so reset/presence detection and ROM search fail: the bus master registers but w1_master_slave_count stays at 0 and no devices are found. Verified on an Amlogic A113X board (DS18B20 on GPIOA_14): with can_sleep restored to false the warnings are gone and the sensor is detected and read again. This must not be applied or backported without the shared-proxy locking fix above; otherwise the original Khadas VIM3 splat returns on boards that genuinely share a meson GPIO. Fixes: 28f240683871 ("pinctrl: meson: mark the GPIO controller as sleeping") Link: https://lore.kernel.org/all/20260105150509.56537-1-bartosz.golaszewski@oss.qualcomm.com/ Signed-off-by: Viacheslav Bocharov Acked-by: Linus Walleij Link: https://patch.msgid.link/20260625115718.1678991-3-v@baodeep.com Signed-off-by: Bartosz Golaszewski Signed-off-by: Sasha Levin --- drivers/pinctrl/meson/pinctrl-meson.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pinctrl/meson/pinctrl-meson.c b/drivers/pinctrl/meson/pinctrl-meson.c index 1555d26df6cdbb..1f05f7f1a9aee2 100644 --- a/drivers/pinctrl/meson/pinctrl-meson.c +++ b/drivers/pinctrl/meson/pinctrl-meson.c @@ -619,7 +619,7 @@ static int meson_gpiolib_register(struct meson_pinctrl *pc) pc->chip.set = meson_gpio_set; pc->chip.base = -1; pc->chip.ngpio = pc->data->num_pins; - pc->chip.can_sleep = true; + pc->chip.can_sleep = false; ret = gpiochip_add_data(&pc->chip, pc); if (ret) { -- 2.53.0