This is a note to let you know that I've just added the patch titled regulator: core: enable power when setting up constraints to the 4.19-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-enable-power-when-setting-up-constrai.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 9224f99447bb9ee3f5a622baaa093278518923ae Author: Olliver Schinagl <oliver@xxxxxxxxxxx> Date: Mon Nov 26 17:27:44 2018 +0200 regulator: core: enable power when setting up constraints [ Upstream commit 2bb1666369339f69f227ad060c250afde94d5c69 ] When a regulator is marked as always on, it is enabled early on, when checking and setting up constraints. It makes the assumption that the bootloader properly initialized the regulator, and just in case enables the regulator anyway. Some constraints however currently get missed, such as the soft-start and ramp-delay. This causes the regulator to be enabled, without the soft-start and ramp-delay being applied, which in turn can cause high-currents or other start-up problems. By moving the always-enabled constraints later in the constraints check, we can at least ensure all constraints for the regulator are followed. Signed-off-by: Olliver Schinagl <oliver@xxxxxxxxxxx> Signed-off-by: Priit Laes <plaes@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 fa8f5fc04d8fd..870baa7036ecd 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1142,17 +1142,6 @@ static int set_machine_constraints(struct regulator_dev *rdev) } } - /* If the constraints say the regulator should be on at this point - * and we have control then make sure it is enabled. - */ - if (rdev->constraints->always_on || rdev->constraints->boot_on) { - ret = _regulator_do_enable(rdev); - if (ret < 0 && ret != -EINVAL) { - rdev_err(rdev, "failed to enable\n"); - return ret; - } - } - if ((rdev->constraints->ramp_delay || rdev->constraints->ramp_disable) && ops->set_ramp_delay) { ret = ops->set_ramp_delay(rdev, rdev->constraints->ramp_delay); @@ -1198,6 +1187,17 @@ static int set_machine_constraints(struct regulator_dev *rdev) } } + /* If the constraints say the regulator should be on at this point + * and we have control then make sure it is enabled. + */ + if (rdev->constraints->always_on || rdev->constraints->boot_on) { + ret = _regulator_do_enable(rdev); + if (ret < 0 && ret != -EINVAL) { + rdev_err(rdev, "failed to enable\n"); + return ret; + } + } + print_constraints(rdev); return 0; }