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()) {
