This is a note to let you know that I've just added the patch titled regulator: core: fix false positive in regulator_late_cleanup() to the 5.16-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: regulator-core-fix-false-positive-in-regulator_late_.patch and it can be found in the queue-5.16 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 3da3c0ce897ebf1927c419f4cb98dfd13cd6e4cc Author: Oliver Barta <oliver.barta@xxxxxxxxx> Date: Tue Feb 8 09:46:45 2022 +0100 regulator: core: fix false positive in regulator_late_cleanup() [ Upstream commit 4e2a354e3775870ca823f1fb29bbbffbe11059a6 ] The check done by regulator_late_cleanup() to detect whether a regulator is on was inconsistent with the check done by _regulator_is_enabled(). While _regulator_is_enabled() takes the enable GPIO into account, regulator_late_cleanup() was not doing that. This resulted in a false positive, e.g. when a GPIO-controlled fixed regulator was used, which was not enabled at boot time, e.g. reg_disp_1v2: reg_disp_1v2 { compatible = "regulator-fixed"; regulator-name = "display_1v2"; regulator-min-microvolt = <1200000>; regulator-max-microvolt = <1200000>; gpio = <&tlmm 148 0>; enable-active-high; }; Such regulator doesn't have an is_enabled() operation. Nevertheless it's state can be determined based on the enable GPIO. The check in regulator_late_cleanup() wrongly assumed that the regulator is on and tried to disable it. Signed-off-by: Oliver Barta <oliver.barta@xxxxxxxxx> Link: https://lore.kernel.org/r/20220208084645.8686-1-oliver.barta@xxxxxxxxx Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 86aa4141efa92..d2553970a67ba 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -6014,9 +6014,8 @@ core_initcall(regulator_init); static int regulator_late_cleanup(struct device *dev, void *data) { struct regulator_dev *rdev = dev_to_rdev(dev); - const struct regulator_ops *ops = rdev->desc->ops; struct regulation_constraints *c = rdev->constraints; - int enabled, ret; + int ret; if (c && c->always_on) return 0; @@ -6029,14 +6028,8 @@ static int regulator_late_cleanup(struct device *dev, void *data) if (rdev->use_count) goto unlock; - /* If we can't read the status assume it's always on. */ - if (ops->is_enabled) - enabled = ops->is_enabled(rdev); - else - enabled = 1; - - /* But if reading the status failed, assume that it's off. */ - if (enabled <= 0) + /* If reading the status failed, assume that it's off. */ + if (_regulator_is_enabled(rdev) <= 0) goto unlock; if (have_full_constraints()) {