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 6B26D43B3CA; Mon, 17 Aug 2026 13:55:42 +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=1786974948; cv=none; b=B8ruuLLejE1qRzDDLYlos7Pr4+LOMnTFoQWjTsFwWT71oOE6bR0oftot3uje+RflGChXXlFSybX21mBDiW/PbSk5VZYWP6YlvwvURGuj7jySG84rV8OzWGUHAGFnCCapqXwjQORTn3z7I0GiAM9LV1yAmUlKvIUNSMoL/dLv86I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786974948; c=relaxed/simple; bh=NF8iMrWw30LQlqjJubrIm/DziuGTiMEjd2GVni0iROM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JP7fUDo0RSskeNB6O5h/MBFxNHz2nDfunxgR1BJREuLzhwVc4V9JdZ8oNn0c0gW3llryZOYBoADYmvr/zboLXkE2jfrHQoS+jssBkpRQ/JKARfDZKFk1Px6aLiggiAXetfbplWLmpuj90et31eT/TkPTtRJd3ZqglRBj0tuIDdg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=IphzuKt5; 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="IphzuKt5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7FAAF1F00A3E; Mon, 17 Aug 2026 13:55:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786974941; bh=u4wyKDZlABibMj5oP1K+J21d8oH9xzMAaYxSRmPbL1w=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=IphzuKt5wD3Gd7MhBd5fcznel74YNZoQwifJjAaZKhQ2F2EIZwvIh3heYhHHNxIO7 Vv7olhJ19VkvvKayAwKMc7um8YPEyl6VYsqH24Xat9detT9mD9uZi1+ZTwngB4pEuz qANOLcGyhw8c70cGkoS+3RaYWPGvkpWqjjUJP7zk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Qingshuang Fu , Guenter Roeck , Sasha Levin Subject: [PATCH 6.18 106/250] hwmon: (ads7828) Fix external VREF regulator handling Date: Mon, 17 Aug 2026 15:31:07 +0200 Message-ID: <20260817132540.870345715@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260817132536.466235697@linuxfoundation.org> References: <20260817132536.466235697@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Qingshuang Fu [ Upstream commit fddb5ceaf901b050ed2a1a7deeecbf97e003435a ] The driver currently has two issues with the external VREF regulator handling in ads7828_probe(): 1. All errors from devm_regulator_get_optional() are ignored, causing the driver to incorrectly fall back to internal VREF even for transient errors like -EPROBE_DEFER or genuine failures like -ENOMEM. 2. The external regulator is never enabled. The driver calls regulator_get_voltage() without first calling regulator_enable(), so the VREF pin may remain unpowered if the regulator is not configured as always-on. Fix both issues by switching to devm_regulator_get_enable_read_voltage(), which handles regulator get, enable, and voltage read in one call. Only -ENODEV (no regulator specified in device tree) should trigger the fallback to internal VREF. All other errors are propagated to the caller. Fixes: a8ddfea09566 ("hwmon: (ads7828) Accept optional parameters from device tree") Signed-off-by: Qingshuang Fu Link: https://lore.kernel.org/r/20260805061645.1331652-1-fffsqian@163.com Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- drivers/hwmon/ads7828.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c index 436637264056c..20ef4992f5bb8 100644 --- a/drivers/hwmon/ads7828.c +++ b/drivers/hwmon/ads7828.c @@ -106,12 +106,11 @@ static int ads7828_probe(struct i2c_client *client) struct ads7828_data *data; struct device *hwmon_dev; unsigned int vref_mv = ADS7828_INT_VREF_MV; - unsigned int vref_uv; + int vref_uv; bool diff_input = false; bool ext_vref = false; unsigned int regval; enum ads7828_chips chip; - struct regulator *reg; data = devm_kzalloc(dev, sizeof(struct ads7828_data), GFP_KERNEL); if (!data) @@ -125,9 +124,11 @@ static int ads7828_probe(struct i2c_client *client) } else if (dev->of_node) { diff_input = of_property_read_bool(dev->of_node, "ti,differential-input"); - reg = devm_regulator_get_optional(dev, "vref"); - if (!IS_ERR(reg)) { - vref_uv = regulator_get_voltage(reg); + vref_uv = devm_regulator_get_enable_read_voltage(dev, "vref"); + if (vref_uv < 0) { + if (vref_uv != -ENODEV) + return vref_uv; + } else { vref_mv = DIV_ROUND_CLOSEST(vref_uv, 1000); if (vref_mv < ADS7828_EXT_VREF_MV_MIN || vref_mv > ADS7828_EXT_VREF_MV_MAX) -- 2.53.0