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 590CD54EED9 for ; Wed, 9 Sep 2026 11:58:18 +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=1788955099; cv=none; b=XTYI7sN2Eg8eX0v+bok1yUitJQJhuD30IdpvzA6K0hV1CBUf0ktCbKiCLz8p+DvS4Us37UoEUaOLc5h79mvFdc1C9Ac9L9yxNLdCmUxp5eWHgBip3NaYZ28/Y+wUEL3fEUsnq/9PBcZFz4Ri/DQ2nGViXgQzGjRx1eu6YvaFcPw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788955099; c=relaxed/simple; bh=6yOjapjZwaembAbnRxNqx7QU2LnZuKwdpeS/s+2Kz1I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=TXNvoYTI9SWB2Ff+kwsMdauU7rnGzj0vgfG+H2EEXHWQFpi2jJI2mgbI5LmVacp1rTd7B0GYbH5Mn5Mk/eRsSXuo4E6SyumlfSiuCYr3IjohTbT0agzORLbbCCJc7bL1K0Qql+QyCAgRflqibPMfHUo4UzAjOsm4ZXTv2YB73rk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mMbZdKP7; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="mMbZdKP7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BB59F1F00A3A; Wed, 9 Sep 2026 11:58:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788955098; bh=DW3fPKS6jWhQqvy4hEVlFVS9mblwHtBnFuMUgLn3xM0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=mMbZdKP79oqd0PAcjb0xnawwaHttgp+utD5VEWhaPiQqDikgxOLpeligbcPfZACkp zq5ZwmKy6McAEQ+QTjvbbYHUKUKz9xRQ8L+3pWFDEnRhAFRJ3smF71bF+muL2wk819 fKuiMW87Gd61jyFmvJJheXBr4ZiFguDCgJOBdYXMxNt+KrKEEoqZ5pzHoTWGNx63QY Da8kA3RQKI3yq0UEj7oC5LfUOOEZjh0jXcsk2AwkpTfJcKY14LGA1Dn/EmzqCQAp4m kvrkcOz18EG1uuPAxNzapcWriMRmL/4ZhP1b11IIXF6AIwqOx7GJ0ZwiO5hVM32Q9/ tsfJ8eCAPEDqQ== From: Sasha Levin To: stable@vger.kernel.org Cc: Jianing Li , Sebastian Reichel , Sasha Levin Subject: [PATCH 5.10.y 4/4] power: supply: max17040: propagate register read errors Date: Wed, 9 Sep 2026 07:58:13 -0400 Message-ID: <20260909115813.2181976-4-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260909115813.2181976-1-sashal@kernel.org> References: <2026090352-handyman-delegate-c138@gregkh> <20260909115813.2181976-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Jianing Li [ Upstream commit 659cc3d8d5ef246263873fce72c8cadeeed073cc ] 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: Sasha Levin --- drivers/power/supply/max17040_battery.c | 26 ++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) diff --git a/drivers/power/supply/max17040_battery.c b/drivers/power/supply/max17040_battery.c index fad244a73c8ea..5f266c0244d8d 100644 --- 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(struct max17040_chip *chip, u16 vcell) 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 max17040_chip *chip) 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); } @@ -263,7 +269,11 @@ static int max17040_get_of_data(struct max17040_chip *chip) 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) @@ -399,10 +409,16 @@ static int max17040_get_property(struct power_supply *psy, 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; -- 2.53.0