diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/regulator/core.c | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 9d3ed13b7f12..df82e2a8442a 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -3106,6 +3106,66 @@ static int _regulator_call_set_voltage_sel(struct regulator_dev *rdev, return ret; } +static int _regulator_set_voltage_sel_step(struct regulator_dev *rdev, + int uV, int new_selector) +{ + const struct regulator_ops *ops = rdev->desc->ops; + int diff, old_sel, curr_sel, ret; + + /* Stepping is only needed if the regulator is enabled. */ + if (!_regulator_is_enabled(rdev)) + goto final_set; + + if (!ops->get_voltage_sel) + return -EINVAL; + + old_sel = ops->get_voltage_sel(rdev); + if (old_sel < 0) + return old_sel; + + diff = new_selector - old_sel; + if (diff == 0) + return 0; /* No change needed. */ + + if (diff > 0) { + /* Stepping up. */ + for (curr_sel = old_sel + rdev->desc->vsel_step; + curr_sel < new_selector; + curr_sel += rdev->desc->vsel_step) { + /* + * Call the callback directly instead of using + * _regulator_call_set_voltage_sel() as we don't + * want to notify anyone yet. Same in the branch + * below. + */ + ret = ops->set_voltage_sel(rdev, curr_sel); + if (ret) + goto try_revert; + } + } else { + /* Stepping down. */ + for (curr_sel = old_sel - rdev->desc->vsel_step; + curr_sel > new_selector; + curr_sel -= rdev->desc->vsel_step) { + ret = ops->set_voltage_sel(rdev, curr_sel); + if (ret) + goto try_revert; + } + } + +final_set: + /* The final selector will trigger the notifiers. */ + return _regulator_call_set_voltage_sel(rdev, uV, new_selector); + +try_revert: + /* + * At least try to return to the previous voltage if setting a new + * one failed. + */ + (void)ops->set_voltage_sel(rdev, old_sel); + return ret; +} + static int _regulator_set_voltage_time(struct regulator_dev *rdev, int old_uV, int new_uV) { @@ -3179,6 +3239,9 @@ static int _regulator_do_set_voltage(struct regulator_dev *rdev, selector = ret; if (old_selector == selector) ret = 0; + else if (rdev->desc->vsel_step) + ret = _regulator_set_voltage_sel_step( + rdev, best_val, selector); else ret = _regulator_call_set_voltage_sel( rdev, best_val, selector); |