[PATCH v3] pwm: meson: modify and simplify calculation in meson_pwm_get_state
Heiner Kallweit
hkallweit1 at gmail.com
Tue May 2 13:33:42 PDT 2023
I don't see a reason why we should treat the case lo < hi differently
and return 0 as period and duty_cycle. The current logic was added with
c375bcbaabdb ("pwm: meson: Read the full hardware state in
meson_pwm_get_state()"), Martin as original author doesn't remember why
it was implemented this way back then.
So let's handle it as normal use case and also remove the optimization
for lo == 0. I think the improved readability is worth it.
Fixes: c375bcbaabdb ("pwm: meson: Read the full hardware state in meson_pwm_get_state()")
Reviewed-by: Uwe Kleine-König <u.kleine-koenig at pengutronix.de>
Cc: stable at vger.kernel.org
Signed-off-by: Heiner Kallweit <hkallweit1 at gmail.com>
---
v2:
- improve commit description
v3:
- make patch a fix
---
drivers/pwm/pwm-meson.c | 14 ++------------
1 file changed, 2 insertions(+), 12 deletions(-)
diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
index 5732300eb..3865538dd 100644
--- a/drivers/pwm/pwm-meson.c
+++ b/drivers/pwm/pwm-meson.c
@@ -351,18 +351,8 @@ static int meson_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
channel->lo = FIELD_GET(PWM_LOW_MASK, value);
channel->hi = FIELD_GET(PWM_HIGH_MASK, value);
- if (channel->lo == 0) {
- state->period = meson_pwm_cnt_to_ns(chip, pwm, channel->hi);
- state->duty_cycle = state->period;
- } else if (channel->lo >= channel->hi) {
- state->period = meson_pwm_cnt_to_ns(chip, pwm,
- channel->lo + channel->hi);
- state->duty_cycle = meson_pwm_cnt_to_ns(chip, pwm,
- channel->hi);
- } else {
- state->period = 0;
- state->duty_cycle = 0;
- }
+ state->period = meson_pwm_cnt_to_ns(chip, pwm, channel->lo + channel->hi);
+ state->duty_cycle = meson_pwm_cnt_to_ns(chip, pwm, channel->hi);
state->polarity = PWM_POLARITY_NORMAL;
--
2.40.0
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