From: Oliver Barta oliver.barta@aptiv.com
stable inclusion from stable-v5.10.104 commit 6e7015d982ee8defa4b45e652b177800bb38c213 bugzilla: https://gitee.com/openeuler/kernel/issues/I56XAC
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ 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@aptiv.com Link: https://lore.kernel.org/r/20220208084645.8686-1-oliver.barta@aptiv.com Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yu Liao liaoyu15@huawei.com Reviewed-by: Wei Li liwei391@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- drivers/regulator/core.c | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-)
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index a6d27334a71d..c65299f8c01d 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -5868,9 +5868,8 @@ 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; @@ -5883,14 +5882,8 @@ 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()) {