[PATCH 2/5] gpio: mvebu: improve pwm period calculation accuracy
flat view
STALE2101d
SUPERSEDED
From: Baruch Siach <baruch@tkos.co.il>
Date: 2021-01-11 11:18:26
Also in:
linux-arm-kernel, linux-pwm
Subsystem:
gpio subsystem, the rest · Maintainers:
Linus Walleij, Bartosz Golaszewski, Linus Torvalds
Revision v1 of 5 in this series.
Revisions (5)
Divide the full period value to reduce rounding error. Reported-by: Uwe Kleine-König <redacted> Signed-off-by: Baruch Siach <baruch@tkos.co.il> --- drivers/gpio/gpio-mvebu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c
index a912a8fed197..c424d88e9e2b 100644
--- a/drivers/gpio/gpio-mvebu.c
+++ b/drivers/gpio/gpio-mvebu.c@@ -715,9 +715,9 @@ static int mvebu_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, else on = 1; - val = (unsigned long long) mvpwm->clk_rate * - (state->period - state->duty_cycle); + val = (unsigned long long) mvpwm->clk_rate * state->period; do_div(val, NSEC_PER_SEC); + val -= on; if (val > UINT_MAX) return -EINVAL; if (val)
--
2.29.2