[PATCH v7 11/13] pwm: sun4i: Use 64-bit division macros for period and duty cycle

[Guru Das Srinagesh]

Because period and duty cycle are defined in the PWM framework structs
as ints with units of nanoseconds, the maximum time duration that can be
set is limited to ~2.147 seconds. Redefining them as u64 values will
enable larger time durations to be set.

As a first step, prepare drivers to handle the switch to u64 period and
duty_cycle by replacing division operations involving pwm period and duty cycle
with their 64-bit equivalents as appropriate. The actual switch to u64 period
and duty_cycle follows as a separate patch.

Where the dividend is 64-bit but the divisor is 32-bit, use *_ULL
macros:
- DIV_ROUND_UP_ULL
- DIV_ROUND_CLOSEST_ULL
- div_u64

Where the divisor is 64-bit (dividend may be 32-bit or 64-bit), use
DIV64_* macros:
- DIV64_U64_ROUND_CLOSEST
- div64_u64

Cc: Maxime Ripard <mripard@xxxxxxxxxx>
Cc: Chen-Yu Tsai <wens@xxxxxxxx>
Cc: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>

Signed-off-by: Guru Das Srinagesh <gurus@xxxxxxxxxxxxxx>
---
 drivers/pwm/pwm-sun4i.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c
index 3e3efa6..772fdf4 100644
--- a/drivers/pwm/pwm-sun4i.c
+++ b/drivers/pwm/pwm-sun4i.c
@@ -286,7 +286,7 @@ 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);
+		usecs_to_jiffies(div_u64(cstate.period, 1000) + 1);
 	sun4i_pwm->needs_delay[pwm->hwpwm] = true;
 
 	if (state->polarity != PWM_POLARITY_NORMAL)
-- 
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