@@ -12,6 +12,7 @@
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
+#include <linux/math64.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
@@ -145,7 +146,6 @@ static int meson_pwm_calc(struct meson_pwm *meson, struct pwm_device *pwm,
struct meson_pwm_channel *channel = pwm_get_chip_data(pwm);
unsigned int duty, period, pre_div, cnt, duty_cnt;
unsigned long fin_freq = -1;
- u64 fin_ps;
duty = state->duty_cycle;
period = state->period;
@@ -164,24 +164,19 @@ static int meson_pwm_calc(struct meson_pwm *meson, struct pwm_device *pwm,
}
dev_dbg(meson->chip.dev, "fin_freq: %lu Hz\n", fin_freq);
- fin_ps = (u64)NSEC_PER_SEC * 1000;
- do_div(fin_ps, fin_freq);
-
- /* Calc pre_div with the period */
- for (pre_div = 0; pre_div <= MISC_CLK_DIV_MASK; pre_div++) {
- cnt = DIV_ROUND_CLOSEST_ULL((u64)period * 1000,
- fin_ps * (pre_div + 1));
- dev_dbg(meson->chip.dev, "fin_ps=%llu pre_div=%u cnt=%u\n",
- fin_ps, pre_div, cnt);
- if (cnt <= 0xffff)
- break;
- }
+ pre_div = div64_u64(fin_freq * (u64)period, NSEC_PER_SEC * 0xffffLL);
if (pre_div > MISC_CLK_DIV_MASK) {
dev_err(meson->chip.dev, "unable to get period pre_div\n");
return -EINVAL;
}
+ cnt = div64_u64(fin_freq * (u64)period, NSEC_PER_SEC * (pre_div + 1));
+ if (cnt > 0xffff) {
+ dev_err(meson->chip.dev, "unable to get period cnt\n");
+ return -EINVAL;
+ }
+
dev_dbg(meson->chip.dev, "period=%u pre_div=%u cnt=%u\n", period,
pre_div, cnt);
@@ -195,8 +190,8 @@ static int meson_pwm_calc(struct meson_pwm *meson, struct pwm_device *pwm,
channel->lo = cnt;
} else {
/* Then check is we can have the duty with the same pre_div */
- duty_cnt = DIV_ROUND_CLOSEST_ULL((u64)duty * 1000,
- fin_ps * (pre_div + 1));
+ duty_cnt = div64_u64(fin_freq * (u64)duty,
+ NSEC_PER_SEC * (pre_div + 1));
if (duty_cnt > 0xffff) {
dev_err(meson->chip.dev, "unable to get duty cycle\n");
return -EINVAL;