UPSTREAM: regulator: pwm: Retrieve correct voltage

The continuous PWM voltage regulator is caching the voltage value in
the ->volt_uV field. While most of the time this value should reflect the
real voltage, sometime it can be sightly different if the PWM device
rounded the set_duty_cycle request.
Moreover, this value is not valid until someone has modified the regulator
output.

Remove the ->volt_uV field and always rely on the PWM state to calculate
the regulator output.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Tested-by: Brian Norris <briannorris@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
(cherry picked from commit d9070fdbe40a04b61262bac0f7ff0c7c29a68015)

Change-Id: Iba7b143c1b08d547b5cd46ac42d9051fb34309df
Signed-off-by: David Wu <david.wu@rock-chips.com>

diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c
index 7d26d3b0eed6122f1ee720db64b23121d36f0103..ae0bebbfda9db0a4b1809cd6447e0506719ab480 100644 (file)
--- a/drivers/regulator/pwm-regulator.c
+++ b/drivers/regulator/pwm-regulator.c
@@ -37,9 +37,6 @@ struct pwm_regulator_data {
 
        int state;
 
-       /* Continuous voltage */
-       int volt_uV;
-
        /* Enable GPIO */
        struct gpio_desc *enb_gpio;
 };
@@ -148,8 +145,13 @@ static int pwm_regulator_is_enabled(struct regulator_dev *dev)
 static int pwm_regulator_get_voltage(struct regulator_dev *rdev)
 {
        struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
+       int min_uV = rdev->constraints->min_uV;
+       int diff = rdev->constraints->max_uV - min_uV;
+       struct pwm_state pstate;
 
-       return drvdata->volt_uV;
+       pwm_get_state(drvdata->pwm, &pstate);
+
+       return min_uV + pwm_get_relative_duty_cycle(&pstate, diff);
 }
 
 static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
@@ -176,8 +178,6 @@ static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
                return ret;
        }
 
-       drvdata->volt_uV = min_uV;
-
        if ((ramp_delay == 0) || !pwm_regulator_is_enabled(rdev))
                return 0;