diff options
| author | Uwe Kleine-König <u.kleine-koenig@baylibre.com> | 2024-07-03 14:00:06 +0300 |
|---|---|---|
| committer | Uwe Kleine-König <ukleinek@kernel.org> | 2024-07-06 00:21:56 +0300 |
| commit | 7346e7a058a2c9aa9ff1cc699c7bf18a402d9f84 (patch) | |
| tree | e5cd4a8357026633b82e4e1593f62854632baf13 /drivers/pwm | |
| parent | f01af3022d4a46362c5dda3d35dea939f3246d10 (diff) | |
| download | linux-7346e7a058a2c9aa9ff1cc699c7bf18a402d9f84.tar.xz | |
pwm: stm32: Always do lazy disabling
When the state changes from enabled to disabled, polarity, duty_cycle
and period are not configured in hardware and TIM_CCER_CCxE is just
cleared. However if the state changes from one disabled state to
another, all parameters are written to hardware because the early exit
from stm32_pwm_apply() is only taken if the pwm is currently enabled.
This yields surprises like: Applying
{ .period = 1, .duty_cycle = 0, .enabled = false }
succeeds if the pwm is initially on, but fails if it's already off
because 1 is a too small period.
Update the check for lazy disable to always exit early if the target
state is disabled, no matter what is currently configured.
Fixes: 7edf7369205b ("pwm: Add driver for STM32 plaftorm")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/20240703110010.672654-2-u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
Diffstat (limited to 'drivers/pwm')
| -rw-r--r-- | drivers/pwm/pwm-stm32.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/pwm/pwm-stm32.c b/drivers/pwm/pwm-stm32.c index 8bae3fd2b330..c586029caf23 100644 --- a/drivers/pwm/pwm-stm32.c +++ b/drivers/pwm/pwm-stm32.c @@ -452,8 +452,9 @@ static int stm32_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, enabled = pwm->state.enabled; - if (enabled && !state->enabled) { - stm32_pwm_disable(priv, pwm->hwpwm); + if (!state->enabled) { + if (enabled) + stm32_pwm_disable(priv, pwm->hwpwm); return 0; } |