Commit ba3e5037 authored by Max Kellermann's avatar Max Kellermann Committed by Thierry Reding
Browse files

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



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

Signed-off-by: default avatarMax Kellermann <max.kellermann@gmail.com>
Acked-by: default avatarUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: default avatarThierry Reding <thierry.reding@gmail.com>
parent c7078972

drivers/pwm/pwm-sun4i.c

+7 −12
Original line number Diff line number Diff line
@@ -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);

	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);