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pwm-sun4i: Calculate "delay_jiffies" directly, eliminate absolute time

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Basically this code did "jiffies + period - jiffies", and we can
simply eliminate the "jiffies" time stamp here.

Signed-off-by: Max Kellermann <max.kellermann@gmail.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This commit is contained in:
Max Kellermann 2022-01-25 13:34:28 +01:00 committed by Thierry Reding
parent c707897203
commit ba3e5037ce
1 changed files with 7 additions and 12 deletions
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19
drivers/pwm/pwm-sun4i.c
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@ -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);