There's no reason to expect a single jiffy has passed since writing
the CTRL register except if a preemption has occured in the meantime.
Avoid introducing unnecessary complexity and simply wait for the whole
period.

Signed-off-by: Roman Beranek <[email protected]>
---
 drivers/pwm/pwm-sun4i.c | 17 ++---------------
 1 file changed, 2 insertions(+), 15 deletions(-)

diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c
index b3ec59a83d00..8218173ce3f6 100644
--- a/drivers/pwm/pwm-sun4i.c
+++ b/drivers/pwm/pwm-sun4i.c
@@ -14,7 +14,6 @@
 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/io.h>
-#include <linux/jiffies.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/of.h>
@@ -89,7 +88,6 @@ struct sun4i_pwm_chip {
        void __iomem *base;
        struct mutex ctrl_lock;
        const struct sun4i_pwm_data *data;
-       unsigned long next_period[2];
 };
 
 static inline struct sun4i_pwm_chip *to_sun4i_pwm_chip(struct pwm_chip *chip)
@@ -242,8 +240,7 @@ 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_us, prescaler = 0;
-       unsigned long now;
+       unsigned int prescaler = 0;
        bool bypass;
 
        pwm_get_state(pwm, &cstate);
@@ -291,8 +288,6 @@ 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));
-       sun4i_pwm->next_period[pwm->hwpwm] = jiffies +
-               nsecs_to_jiffies(cstate.period + 1000);
 
        if (state->polarity != PWM_POLARITY_NORMAL)
                ctrl &= ~BIT_CH(PWM_ACT_STATE, pwm->hwpwm);
@@ -314,15 +309,7 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct 
pwm_device *pwm,
        }
 
        /* We need a full period to elapse before disabling the channel. */
-       now = jiffies;
-       if (time_before(now, sun4i_pwm->next_period[pwm->hwpwm])) {
-               delay_us = jiffies_to_usecs(sun4i_pwm->next_period[pwm->hwpwm] -
-                                          now);
-               if ((delay_us / 500) > MAX_UDELAY_MS)
-                       msleep(delay_us / 1000 + 1);
-               else
-                       usleep_range(delay_us, delay_us * 2);
-       }
+       fsleep(cstate.period / NSEC_PER_USEC + 1);
 
        ctrl &= ~BIT_CH(PWM_CLK_GATING, pwm->hwpwm);
        sun4i_pwm_writel(sun4i_pwm, ctrl, PWM_CTRL_REG);
-- 
2.31.1

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