[PATCH v5 30/46] regulator: pwm: retrieve correct voltage
From: Boris Brezillon <hidden>
Date: 2016-03-30 20:05:46
Also in:
dri-devel, intel-gfx, linux-arm-kernel, linux-clk, linux-fbdev, linux-leds, linux-pwm, linux-rockchip, linux-samsung-soc, lkml
Subsystem:
the rest, voltage and current regulator framework · Maintainers:
Linus Torvalds, Liam Girdwood, Mark Brown
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-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> --- drivers/regulator/pwm-regulator.c | 23 +++++++++++++++++------ 1 file changed, 17 insertions(+), 6 deletions(-)
diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c
index 9374796..77f42d8 100644
--- a/drivers/regulator/pwm-regulator.c
+++ b/drivers/regulator/pwm-regulator.c@@ -35,9 +35,6 @@ struct pwm_regulator_data { struct regulator_ops ops; int state; - - /* Continuous voltage */ - int volt_uV; }; struct pwm_voltages {
@@ -167,11 +164,27 @@ static int pwm_voltage_to_duty_cycle_percentage(struct regulator_dev *rdev, int return ((req_uV * 100) - (min_uV * 100)) / diff; } +static int pwm_duty_cycle_percentage_to_voltage(struct regulator_dev *rdev, + int dutycycle) +{ + int min_uV = rdev->constraints->min_uV; + int max_uV = rdev->constraints->max_uV; + int diff = max_uV - min_uV; + + return min_uV + ((diff * dutycycle) / 100); +} + static int pwm_regulator_get_voltage(struct regulator_dev *rdev) { struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev); + struct pwm_state pstate; + u64 dutycycle; - return drvdata->volt_uV; + pwm_get_state(drvdata->pwm, &pstate); + dutycycle = pstate.duty_cycle * 100; + do_div(dutycycle, pstate.period); + + return pwm_duty_cycle_percentage_to_voltage(rdev, dutycycle); } static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
@@ -196,8 +209,6 @@ static int pwm_regulator_set_voltage(struct regulator_dev *rdev, return ret; } - drvdata->volt_uV = min_uV; - /* Delay required by PWM regulator to settle to the new voltage */ usleep_range(ramp_delay, ramp_delay + 1000);
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2.5.0