Basically this code did "jiffies + period - jiffies", and we can simply eliminate the "jiffies" time stamp here.
Cc: stable@vger.kernel.org Signed-off-by: Max Kellermann max.kellermann@gmail.com --- drivers/pwm/pwm-sun4i.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-)
diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c index c7c564a6bf36..b44deececb8b 100644 --- a/drivers/pwm/pwm-sun4i.c +++ b/drivers/pwm/pwm-sun4i.c @@ -234,9 +234,8 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, struct pwm_state cstate; u32 ctrl, duty = 0, period = 0, val; int ret; + unsigned int delay_jiffies; unsigned int delay_us, prescaler = 0; - unsigned long now; - unsigned long next_period; bool bypass;
pwm_get_state(pwm, &cstate); @@ -284,8 +283,6 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
val = (duty & PWM_DTY_MASK) | PWM_PRD(period); sun4i_pwm_writel(sun4i_pwm, val, PWM_CH_PRD(pwm->hwpwm)); - next_period = jiffies + - nsecs_to_jiffies(cstate.period + 1000);
if (state->polarity != PWM_POLARITY_NORMAL) ctrl &= ~BIT_CH(PWM_ACT_STATE, pwm->hwpwm); @@ -305,14 +302,12 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, return 0;
/* We need a full period to elapse before disabling the channel. */ - now = jiffies; - if (time_before(now, next_period)) { - delay_us = jiffies_to_usecs(next_period - now); - if ((delay_us / 500) > MAX_UDELAY_MS) - msleep(delay_us / 1000 + 1); - else - usleep_range(delay_us, delay_us * 2); - } + delay_jiffies = nsecs_to_jiffies(cstate.period + 1000); + delay_us = jiffies_to_usecs(delay_jiffies); + if ((delay_us / 500) > MAX_UDELAY_MS) + msleep(delay_us / 1000 + 1); + else + usleep_range(delay_us, delay_us * 2);
spin_lock(&sun4i_pwm->ctrl_lock); ctrl = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG);