regulator: pwm: Switch to the atomic PWM API

Use the atomic API wherever appropriate and get rid of pwm_apply_args()
call (the reference period and polarity are now explicitly set when
calling pwm_apply_state()).

We also make use of the pwm_set_relative_duty_cycle() helper to ease
relative to absolute duty_cycle conversion.

Note that changes introduced by commit fd786fb0276a ("regulator: pwm:
Try to avoid voltage error in duty cycle calculation") are no longer
needed because pwm_set_relative_duty_cycle() takes care of all rounding
approximation for us.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Tested-by: Brian Norris <briannorris@chromium.org>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

1 files changed, 10 insertions, 28 deletions

diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c
index cb2f22c02469..7920411057af 100644
--- a/drivers/regulator/pwm-regulator.c
+++ b/drivers/regulator/pwm-regulator.c
@@ -63,16 +63,14 @@ static int pwm_regulator_set_voltage_sel(struct regulator_dev *rdev,
                                          unsigned selector)
 {
         struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
-        struct pwm_args pargs;
-        int dutycycle;
+        struct pwm_state pstate;
         int ret;
 
-        pwm_get_args(drvdata->pwm, &pargs);
+        pwm_init_state(drvdata->pwm, &pstate);
+        pwm_set_relative_duty_cycle(&pstate,
+                        drvdata->duty_cycle_table[selector].dutycycle, 100);
 
-        dutycycle = (pargs.period *
-                    drvdata->duty_cycle_table[selector].dutycycle) / 100;
-
-        ret = pwm_config(drvdata->pwm, dutycycle, pargs.period);
+        ret = pwm_apply_state(drvdata->pwm, &pstate);
         if (ret) {
                 dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
                 return ret;
@@ -139,35 +137,19 @@ static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
 {
         struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
         unsigned int ramp_delay = rdev->constraints->ramp_delay;
-        struct pwm_args pargs;
         unsigned int req_diff = min_uV - rdev->constraints->min_uV;
+        struct pwm_state pstate;
         unsigned int diff;
-        unsigned int duty_pulse;
-        u64 req_period;
-        u32 rem;
         int old_uV = pwm_regulator_get_voltage(rdev);
         int ret;
 
-        pwm_get_args(drvdata->pwm, &pargs);
+        pwm_init_state(drvdata->pwm, &pstate);
         diff = rdev->constraints->max_uV - rdev->constraints->min_uV;
 
-        /* First try to find out if we get the iduty cycle time which is
-         * factor of PWM period time. If (request_diff_to_min * pwm_period)
-         * is perfect divided by voltage_range_diff then it is possible to
-         * get duty cycle time which is factor of PWM period. This will help
-         * to get output voltage nearer to requested value as there is no
-         * calculation loss.
-         */
-        req_period = req_diff * pargs.period;
-        div_u64_rem(req_period, diff, &rem);
-        if (!rem) {
-                do_div(req_period, diff);
-                duty_pulse = (unsigned int)req_period;
-        } else {
-                duty_pulse = (pargs.period / 100) * ((req_diff * 100) / diff);
-        }
+        /* We pass diff as the scale to get a uV precision. */
+        pwm_set_relative_duty_cycle(&pstate, req_diff, diff);
 
-        ret = pwm_config(drvdata->pwm, duty_pulse, pargs.period);
+        ret = pwm_apply_state(drvdata->pwm, &pstate);
         if (ret) {
                 dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
                 return ret;