From 7a32b589a9c856493bccb02db55047edc04eee7b Mon Sep 17 00:00:00 2001 From: MyungJoo Ham Date: Fri, 11 Mar 2011 10:13:59 +0900 Subject: [PATCH] Regulator: add suspend-finish API for regulator core. The regulator core had suspend-prepare that turns off the regulators when entering a system-wide suspend. However, it did not have suspend-finish that pairs with suspend-prepare and the regulator core has assumed that the regulator devices and their drivers support autonomous recover at resume. This patch adds regulator_suspend_finish that pairs with the previously-existed regulator_suspend_prepare. The function regulator_suspend_finish turns on the regulators that have always_on set or positive use_count so that we can reset the regulator states appropriately at resume. In regulator_suspend_finish, if has_full_constraints, it disables unnecessary regulators. Signed-off-by: MyungJoo Ham Signed-off-by: Kyungmin Park Acked-by: Mark Brown -- Updates v3 comments corrected (Thanks to Igor) v2 disable unnecessary regulators (Thanks to Mark) Signed-off-by: Liam Girdwood --- drivers/regulator/core.c | 41 +++++++++++++++++++++++++++++++ include/linux/regulator/machine.h | 1 + 2 files changed, 42 insertions(+) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index a2dc6223e8d2..e611f6797e6a 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -2655,6 +2655,47 @@ out: } EXPORT_SYMBOL_GPL(regulator_suspend_prepare); +/** + * regulator_suspend_finish - resume regulators from system wide suspend + * + * Turn on regulators that might be turned off by regulator_suspend_prepare + * and that should be turned on according to the regulators properties. + */ +int regulator_suspend_finish(void) +{ + struct regulator_dev *rdev; + int ret = 0, error; + + mutex_lock(®ulator_list_mutex); + list_for_each_entry(rdev, ®ulator_list, list) { + struct regulator_ops *ops = rdev->desc->ops; + + mutex_lock(&rdev->mutex); + if ((rdev->use_count > 0 || rdev->constraints->always_on) && + ops->enable) { + error = ops->enable(rdev); + if (error) + ret = error; + } else { + if (!has_full_constraints) + goto unlock; + if (!ops->disable) + goto unlock; + if (ops->is_enabled && !ops->is_enabled(rdev)) + goto unlock; + + error = ops->disable(rdev); + if (error) + ret = error; + } +unlock: + mutex_unlock(&rdev->mutex); + } + mutex_unlock(®ulator_list_mutex); + return ret; +} +EXPORT_SYMBOL_GPL(regulator_suspend_finish); + /** * regulator_has_full_constraints - the system has fully specified constraints * diff --git a/include/linux/regulator/machine.h b/include/linux/regulator/machine.h index 761c745b9c24..c4c4fc45f856 100644 --- a/include/linux/regulator/machine.h +++ b/include/linux/regulator/machine.h @@ -186,6 +186,7 @@ struct regulator_init_data { }; int regulator_suspend_prepare(suspend_state_t state); +int regulator_suspend_finish(void); #ifdef CONFIG_REGULATOR void regulator_has_full_constraints(void); -- 2.20.1