diff options
Diffstat (limited to 'drivers/regulator/core.c')
| -rw-r--r-- | drivers/regulator/core.c | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 8588a2490e0a..01f7702a805d 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -28,6 +28,7 @@ static DEFINE_MUTEX(regulator_list_mutex); static LIST_HEAD(regulator_list); static LIST_HEAD(regulator_map_list); +static int has_full_constraints; /* * struct regulator_map @@ -2143,6 +2144,23 @@ out: EXPORT_SYMBOL_GPL(regulator_suspend_prepare); /** + * regulator_has_full_constraints - the system has fully specified constraints + * + * Calling this function will cause the regulator API to disable all + * regulators which have a zero use count and don't have an always_on + * constraint in a late_initcall. + * + * The intention is that this will become the default behaviour in a + * future kernel release so users are encouraged to use this facility + * now. + */ +void regulator_has_full_constraints(void) +{ + has_full_constraints = 1; +} +EXPORT_SYMBOL_GPL(regulator_has_full_constraints); + +/** * rdev_get_drvdata - get rdev regulator driver data * @rdev: regulator * @@ -2209,3 +2227,77 @@ static int __init regulator_init(void) /* init early to allow our consumers to complete system booting */ core_initcall(regulator_init); + +static int __init regulator_init_complete(void) +{ + struct regulator_dev *rdev; + struct regulator_ops *ops; + struct regulation_constraints *c; + int enabled, ret; + const char *name; + + mutex_lock(®ulator_list_mutex); + + /* If we have a full configuration then disable any regulators + * which are not in use or always_on. This will become the + * default behaviour in the future. + */ + list_for_each_entry(rdev, ®ulator_list, list) { + ops = rdev->desc->ops; + c = rdev->constraints; + + if (c->name) + name = c->name; + else if (rdev->desc->name) + name = rdev->desc->name; + else + name = "regulator"; + + if (!ops->disable || c->always_on) + continue; + + mutex_lock(&rdev->mutex); + + if (rdev->use_count) + goto unlock; + + /* If we can't read the status assume it's on. */ + if (ops->is_enabled) + enabled = ops->is_enabled(rdev); + else + enabled = 1; + + if (!enabled) + goto unlock; + + if (has_full_constraints) { + /* We log since this may kill the system if it + * goes wrong. */ + printk(KERN_INFO "%s: disabling %s\n", + __func__, name); + ret = ops->disable(rdev); + if (ret != 0) { + printk(KERN_ERR + "%s: couldn't disable %s: %d\n", + __func__, name, ret); + } + } else { + /* The intention is that in future we will + * assume that full constraints are provided + * so warn even if we aren't going to do + * anything here. + */ + printk(KERN_WARNING + "%s: incomplete constraints, leaving %s on\n", + __func__, name); + } + +unlock: + mutex_unlock(&rdev->mutex); + } + + mutex_unlock(®ulator_list_mutex); + + return 0; +} +late_initcall(regulator_init_complete); |