| Message ID | 1464942192-25967-11-git-send-email-boris.brezillon@free-electrons.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
+ Laxman Hi, On Fri, Jun 03, 2016 at 10:23:08AM +0200, Boris Brezillon wrote: > 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. > > Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> > --- > drivers/regulator/pwm-regulator.c | 38 ++++++++++---------------------------- > 1 file changed, 10 insertions(+), 28 deletions(-) > > diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c > index 524b43f..bf033fd 100644 > --- a/drivers/regulator/pwm-regulator.c > +++ b/drivers/regulator/pwm-regulator.c > @@ -59,16 +59,14 @@ 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_prepare_new_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; > @@ -126,34 +124,18 @@ 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 ret; > > - pwm_get_args(drvdata->pwm, &pargs); > + pwm_prepare_new_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); Notably, you're dropping much of Laxman's commit fd786fb0276a ("regulator: pwm: Try to avoid voltage error in duty cycle calculation"), but I believe the DIV_ROUND_CLOSEST_ULL() in pwm_set_relative_duty_cycle() solves his problem better. > > - 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; Reviewed-by: Brian Norris <briannorris@chromium.org> Tested-by: Brian Norris <briannorris@chromium.org>
On Fri, 3 Jun 2016 13:50:28 -0700 Brian Norris <briannorris@chromium.org> wrote: > + Laxman > > Hi, > > On Fri, Jun 03, 2016 at 10:23:08AM +0200, Boris Brezillon wrote: > > 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. > > > > Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> > > --- > > drivers/regulator/pwm-regulator.c | 38 ++++++++++---------------------------- > > 1 file changed, 10 insertions(+), 28 deletions(-) > > > > diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c > > index 524b43f..bf033fd 100644 > > --- a/drivers/regulator/pwm-regulator.c > > +++ b/drivers/regulator/pwm-regulator.c > > @@ -59,16 +59,14 @@ 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_prepare_new_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; > > @@ -126,34 +124,18 @@ 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 ret; > > > > - pwm_get_args(drvdata->pwm, &pargs); > > + pwm_prepare_new_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); > > Notably, you're dropping much of Laxman's commit fd786fb0276a ("regulator: > pwm: Try to avoid voltage error in duty cycle calculation"), but I > believe the DIV_ROUND_CLOSEST_ULL() in pwm_set_relative_duty_cycle() > solves his problem better. Oops, forgot to comment on that in the commit message. Indeed, the use of pwm_set_relative_duty_cycle() solves the problem Laxman was seeing. > > > > > - 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; > > Reviewed-by: Brian Norris <briannorris@chromium.org> > Tested-by: Brian Norris <briannorris@chromium.org>
On Saturday 04 June 2016 11:58 AM, Boris Brezillon wrote: > On Fri, 3 Jun 2016 13:50:28 -0700 > Brian Norris <briannorris@chromium.org> wrote: > >> + Laxman >> >> Hi, >> >> On Fri, Jun 03, 2016 at 10:23:08AM +0200, Boris Brezillon wrote: >>> - * 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); >> Notably, you're dropping much of Laxman's commit fd786fb0276a ("regulator: >> pwm: Try to avoid voltage error in duty cycle calculation"), but I >> believe the DIV_ROUND_CLOSEST_ULL() in pwm_set_relative_duty_cycle() >> solves his problem better. > Oops, forgot to comment on that in the commit message. Indeed, the use > of pwm_set_relative_duty_cycle() solves the problem Laxman was seeing. > Yaah, the issue which I was seeing and had fix will be resolved with this also. I wanted to do req_diff * period first before any scaling/division. Function pwm_set_relative_duty_cycle() does the same, and hence it is fine. state->duty_cycle = DIV_ROUND_CLOSEST_ULL((u64)val * state->period, + scale); Acked-by: Laxman Dewangan <ldewangan@nvidia.com> Thanks, Laxman
diff --git a/drivers/regulator/pwm-regulator.c b/drivers/regulator/pwm-regulator.c index 524b43f..bf033fd 100644 --- a/drivers/regulator/pwm-regulator.c +++ b/drivers/regulator/pwm-regulator.c @@ -59,16 +59,14 @@ 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_prepare_new_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; @@ -126,34 +124,18 @@ 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 ret; - pwm_get_args(drvdata->pwm, &pargs); + pwm_prepare_new_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;
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. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> --- drivers/regulator/pwm-regulator.c | 38 ++++++++++---------------------------- 1 file changed, 10 insertions(+), 28 deletions(-)