diff options
| author | Max Kellermann <max.kellermann@gmail.com> | 2022-01-25 13:34:28 +0100 |
|---|---|---|
| committer | Thierry Reding <thierry.reding@gmail.com> | 2022-04-22 17:43:48 +0200 |
| commit | ba3e5037ceeb920e98970e2342edd7ab390217c0 (patch) | |
| tree | 74e44007f9c8390177d1dfcdf709581f03c901ac /drivers/pwm/pwm-sun4i.c | |
| parent | c7078972038a04549cfb1ab1f3f6554db9c31446 (diff) | |
| download | lwn-ba3e5037ceeb920e98970e2342edd7ab390217c0.tar.gz lwn-ba3e5037ceeb920e98970e2342edd7ab390217c0.zip | |
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: 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>
Diffstat (limited to 'drivers/pwm/pwm-sun4i.c')
| -rw-r--r-- | drivers/pwm/pwm-sun4i.c | 19 |
1 files changed, 7 insertions, 12 deletions
diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c index 24db8c9b4bc6..9134db4f52a9 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); |