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 8ECA038E8DD; Fri, 4 Sep 2026 05:28:23 +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=1788499704; cv=none; b=SSF+d7asdb/025flhBo4oi9JYvF1lGzZaJzt4o2I8pBJdFwqQWYHuK+UzMY+nmI09OfWtY/3N5ryfbW7VfnaHsxyX1VroPcgaN5QIRH21FReOsOfr1U+xsX0qcHGJrhm2Z4/E+jze2GL7Nm+zbtHIWXF9D2xIt8b1d5SdysCxwU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788499704; c=relaxed/simple; bh=Byn+Mpyl2gvVS/b8IvvageUSXOkuLz2gXH8hif9HGhY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LGwAam9f2rvPqzSxIrm4B8fgUO+LRnILLW39/96y3PaycZo+BcQlLNMqJPVLWghD6otUA3vt9kZk1YvB9pgjqOnHeK9i4umNS/mr0IBn8JpLGLW77CWoeL6GfpvtNHVSKbSQ8/KAxgjEfNyDxUSW/0VHl/TK5G/V2FRdQMUuxzE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=bOmG8FdW; 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="bOmG8FdW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E96021F00A3D; Fri, 4 Sep 2026 05:28:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788499703; bh=3iBkPaVa+9li+ct4/Ds/YP/Ta0bJ5fWtFoz9JL+U3l8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=bOmG8FdWeN2NQ7EdHJWpNwlYpVtpe7aWCPSrI+Sr8zOkndd7hdgSQ2YsNBDPuCU8Z SDjbI7ydZixThuMjuaRA0ysDccqUO9EoSTNPQLpS903BfUCi3qE0xLqNGPcEjovOXe Ng5tdpbdfFIX0PWIKlCamCUuRJpcwDII7qLl3Kws= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jianing Li , Sebastian Reichel Subject: [PATCH 7.2 512/713] power: supply: max17040: propagate register read errors Date: Fri, 4 Sep 2026 06:58:00 +0200 Message-ID: <20260904045815.296586277@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260904045803.810145556@linuxfoundation.org> References: <20260904045803.810145556@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 7.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jianing Li commit 659cc3d8d5ef246263873fce72c8cadeeed073cc upstream. max17040_get_vcell() and max17040_get_soc() ignore errors returned by regmap_read(). When an I2C transfer fails, the uninitialized register value is converted and reported to userspace as a valid voltage or state of charge. The polling worker can also replace the cached state of charge with the bogus value and emit a spurious change event. Propagate read errors through the power supply get_property callback and keep the last valid cached state of charge when polling fails. Fixes: c6f4a42de60b ("Add MAX17040 Fuel Gauge driver") Cc: stable@vger.kernel.org Signed-off-by: Jianing Li Link: https://patch.msgid.link/20260727064825.948-1-m13940358460@163.com Signed-off-by: Sebastian Reichel Signed-off-by: Greg Kroah-Hartman --- drivers/power/supply/max17040_battery.c | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) --- a/drivers/power/supply/max17040_battery.c +++ b/drivers/power/supply/max17040_battery.c @@ -192,8 +192,11 @@ static int max17040_raw_vcell_to_uvolts( static int max17040_get_vcell(struct max17040_chip *chip) { u32 vcell; + int ret; - regmap_read(chip->regmap, MAX17040_VCELL, &vcell); + ret = regmap_read(chip->regmap, MAX17040_VCELL, &vcell); + if (ret) + return ret; return max17040_raw_vcell_to_uvolts(chip, vcell); } @@ -201,8 +204,11 @@ static int max17040_get_vcell(struct max static int max17040_get_soc(struct max17040_chip *chip) { u32 soc; + int ret; - regmap_read(chip->regmap, MAX17040_SOC, &soc); + ret = regmap_read(chip->regmap, MAX17040_SOC, &soc); + if (ret) + return ret; return soc >> (chip->quirk_double_soc ? 9 : 8); } @@ -261,7 +267,11 @@ static int max17040_get_of_data(struct m static void max17040_check_changes(struct max17040_chip *chip) { - chip->soc = max17040_get_soc(chip); + int soc; + + soc = max17040_get_soc(chip); + if (soc >= 0) + chip->soc = soc; } static void max17040_queue_work(struct max17040_chip *chip) @@ -396,10 +406,16 @@ static int max17040_get_property(struct val->intval = max17040_get_online(chip); break; case POWER_SUPPLY_PROP_VOLTAGE_NOW: - val->intval = max17040_get_vcell(chip); + ret = max17040_get_vcell(chip); + if (ret < 0) + return ret; + val->intval = ret; break; case POWER_SUPPLY_PROP_CAPACITY: - val->intval = max17040_get_soc(chip); + ret = max17040_get_soc(chip); + if (ret < 0) + return ret; + val->intval = ret; break; case POWER_SUPPLY_PROP_CAPACITY_ALERT_MIN: val->intval = chip->low_soc_alert;