[PATCH 3/5] gpio: mvebu: make pwm apply/get_state closer to idempotent
From: Baruch Siach <baruch@tkos.co.il>
Date: 2021-01-11 11:18:28
Also in:
linux-gpio, linux-pwm
Subsystem:
gpio subsystem, the rest · Maintainers:
Linus Walleij, Bartosz Golaszewski, Linus Torvalds
Round up the result of division in period/duty_cycle calculation to make the result closer to idempotent. Reported-by: Uwe Kleine-König <redacted> Signed-off-by: Baruch Siach <baruch@tkos.co.il> --- drivers/gpio/gpio-mvebu.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c
index c424d88e9e2b..6fc64846eda3 100644
--- a/drivers/gpio/gpio-mvebu.c
+++ b/drivers/gpio/gpio-mvebu.c@@ -668,7 +668,7 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip, regmap_read(mvpwm->regs, mvebu_pwmreg_blink_on_duration(mvpwm), &u); val = (unsigned long long) u * NSEC_PER_SEC; - do_div(val, mvpwm->clk_rate); + val = DIV_ROUND_UP_ULL(val, mvpwm->clk_rate); if (val > UINT_MAX) state->duty_cycle = UINT_MAX; else if (val)
@@ -680,7 +680,7 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip, regmap_read(mvpwm->regs, mvebu_pwmreg_blink_off_duration(mvpwm), &u); val += (unsigned long long) u; /* period = on + off duration */ val *= NSEC_PER_SEC; - do_div(val, mvpwm->clk_rate); + val = DIV_ROUND_UP_ULL(val, mvpwm->clk_rate); if (val > UINT_MAX) state->period = UINT_MAX; else if (val)
@@ -707,7 +707,7 @@ static int mvebu_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, unsigned int on, off; val = (unsigned long long) mvpwm->clk_rate * state->duty_cycle; - do_div(val, NSEC_PER_SEC); + val = DIV_ROUND_UP_ULL(val, NSEC_PER_SEC); if (val > UINT_MAX) return -EINVAL; if (val)
@@ -716,7 +716,7 @@ static int mvebu_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, on = 1; val = (unsigned long long) mvpwm->clk_rate * state->period; - do_div(val, NSEC_PER_SEC); + val = DIV_ROUND_UP_ULL(val, NSEC_PER_SEC); val -= on; if (val > UINT_MAX) return -EINVAL;
--
2.29.2
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