diff options
| author | Uwe Kleine-König <u.kleine-koenig@baylibre.com> | 2025-04-05 11:27:12 +0200 |
|---|---|---|
| committer | Uwe Kleine-König <ukleinek@kernel.org> | 2025-04-07 15:10:13 +0200 |
| commit | 00e53d0f4baedd72196b65f00698b2a5a537dc2b (patch) | |
| tree | 27a24351dfff3fe65e439814e129cb1e8a18a3a4 | |
| parent | 928446a5302eee30ebb32075c0db5dda5a138fb7 (diff) | |
pwm: Let pwm_set_waveform() succeed even if lowlevel driver rounded up
Waveform parameters are supposed to be rounded down to the next value
possible for the hardware. However when a requested value is too small,
.round_waveform_tohw() is supposed to pick the next bigger value and
return 1. Let pwm_set_waveform() behave in the same way.
This creates consistency between pwm_set_waveform_might_sleep() with
exact=false and pwm_round_waveform_might_sleep() +
pwm_set_waveform_might_sleep() with exact=true.
The PWM_DEBUG rounding check has to be adapted to only trigger if no
uprounding happend.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Tested-by: Trevor Gamblin <tgamblin@baylibre.com>
Link: https://lore.kernel.org/r/353dc6ae31be815e41fd3df89c257127ca0d1a09.1743844730.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
| -rw-r--r-- | drivers/pwm/core.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index a40c511e0096..0387bd838487 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -322,7 +322,7 @@ static int __pwm_set_waveform(struct pwm_device *pwm, const struct pwm_ops *ops = chip->ops; char wfhw[WFHWSIZE]; struct pwm_waveform wf_rounded; - int err; + int err, ret_tohw; BUG_ON(WFHWSIZE < ops->sizeof_wfhw); @@ -332,16 +332,16 @@ static int __pwm_set_waveform(struct pwm_device *pwm, if (!pwm_wf_valid(wf)) return -EINVAL; - err = __pwm_round_waveform_tohw(chip, pwm, wf, &wfhw); - if (err) - return err; + ret_tohw = __pwm_round_waveform_tohw(chip, pwm, wf, &wfhw); + if (ret_tohw < 0) + return ret_tohw; if ((IS_ENABLED(CONFIG_PWM_DEBUG) || exact) && wf->period_length_ns) { err = __pwm_round_waveform_fromhw(chip, pwm, &wfhw, &wf_rounded); if (err) return err; - if (IS_ENABLED(CONFIG_PWM_DEBUG) && !pwm_check_rounding(wf, &wf_rounded)) + if (IS_ENABLED(CONFIG_PWM_DEBUG) && ret_tohw == 0 && !pwm_check_rounding(wf, &wf_rounded)) dev_err(&chip->dev, "Wrong rounding: requested %llu/%llu [+%llu], result %llu/%llu [+%llu]\n", wf->duty_length_ns, wf->period_length_ns, wf->duty_offset_ns, wf_rounded.duty_length_ns, wf_rounded.period_length_ns, wf_rounded.duty_offset_ns); @@ -382,7 +382,8 @@ static int __pwm_set_waveform(struct pwm_device *pwm, wf_rounded.duty_length_ns, wf_rounded.period_length_ns, wf_rounded.duty_offset_ns, wf_set.duty_length_ns, wf_set.period_length_ns, wf_set.duty_offset_ns); } - return 0; + + return ret_tohw; } /** |