[RFC PATCH 14/15] regulator: pwm: implement ->enable(), ->disable() and ->is_enabled methods

Boris Brezillon
2015-07-01T08:22:00Z

Implement the ->enable(), ->disable() and ->is_enabled methods and remove
the PWM call in ->set_voltage_sel().
This is particularly important for critical regulators tagged as always-on,
because not claiming the PWM (and its dependencies) might lead to
unpredictable behavior (like a system hang because the PWM clk is only
claimed when the PWM device is enabled).

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
---
drivers/regulator/pwm-regulator.c | 32 ++++++++++++++++++++++++++------
1 file changed, 26 insertions(+), 6 deletions(-)

diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c
index 12b4d9d..8159518 100644
--- a/drivers/regulator/pwm-regulator.c
+++ b/drivers/regulator/pwm-regulator.c
@@ -59,12 +59,6 @@ static int pwm_regulator_set_voltage_sel(struct regulator_dev *rdev,

drvdata->state = selector;

- ret = pwm_enable(drvdata->pwm);
- if (ret) {
- dev_err(&rdev->dev, "Failed to enable PWM\n");
- return ret;
- }
-
return 0;
}

@@ -79,11 +73,37 @@ static int pwm_regulator_list_voltage(struct regulator_dev *rdev,
return drvdata->duty_cycle_table[selector].uV;
}

+static int pwm_regulator_enable(struct regulator_dev *dev)
+{
+ struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
+
+ return pwm_enable(drvdata->pwm);
+}
+
+static int pwm_regulator_disable(struct regulator_dev *dev)
+{
+ struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
+
+ pwm_disable(drvdata->pwm);
+
+ return 0;
+}
+
+static int pwm_regulator_is_enabled(struct regulator_dev *dev)
+{
+ struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
+
+ return pwm_is_enabled(drvdata->pwm);
+}
+
static struct regulator_ops pwm_regulator_voltage_ops = {
.set_voltage_sel = pwm_regulator_set_voltage_sel,
.get_voltage_sel = pwm_regulator_get_voltage_sel,
.list_voltage = pwm_regulator_list_voltage,
.map_voltage = regulator_map_voltage_iterate,
+ .enable = pwm_regulator_enable,
+ .disable = pwm_regulator_disable,
+ .is_enabled = pwm_regulator_is_enabled,
};

static struct regulator_desc pwm_regulator_desc = {
--
1.9.1