[RFC PATCH 3/4] pwm: sun4i: Move delay to function

Pascal Roeleven
2020-03-17T16:00:10Z

Move the delay to a function so we can reuse it.

Signed-off-by: Pascal Roeleven <dev@pascalroeleven.nl>
---
drivers/pwm/pwm-sun4i.c | 32 ++++++++++++++++++--------------
1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c
index 56942036b..a11d00f96 100644
--- a/drivers/pwm/pwm-sun4i.c
+++ b/drivers/pwm/pwm-sun4i.c
@@ -89,7 +89,6 @@ struct sun4i_pwm_chip {
void __iomem *base;
spinlock_t 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)
@@ -228,6 +227,20 @@ static int sun4i_pwm_calculate(struct sun4i_pwm_chip *sun4i_pwm,
return 0;
}

+static void sun4i_pwm_wait(unsigned long next_period) {
+ unsigned int delay_us;
+ unsigned long now;
+
+ 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);
+ }
+}
+
static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
const struct pwm_state *state)
{
@@ -235,8 +248,8 @@ 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_us, prescaler = 0;
- unsigned long now;
+ unsigned int prescaler = 0;
+ unsigned long next_period;
bool bypass;

pwm_get_state(pwm, &cstate);
@@ -284,8 +297,7 @@ 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 +
- usecs_to_jiffies(cstate.period / 1000 + 1);
+ next_period = jiffies + usecs_to_jiffies(cstate.period / 1000 + 1);

if (state->polarity != PWM_POLARITY_NORMAL)
ctrl &= ~BIT_CH(PWM_ACT_STATE, pwm->hwpwm);
@@ -308,15 +320,7 @@ 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, 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);
- }
+ sun4i_pwm_wait(next_period);

spin_lock(&sun4i_pwm->ctrl_lock);
ctrl = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG);
--
2.20.1