[PATCH AUTOSEL 4.9 138/251] pwm: meson: Don't disable PWM when setting duty repeatedly

From: Sasha Levin
Date: Thu Jan 16 2020 - 13:05:45 EST


From: Bichao Zheng <bichao.zheng@xxxxxxxxxxx>

[ Upstream commit a279345807e1e0ae79567a52cfdd9d30c9174a3c ]

There is an abnormally low about 20ms,when setting duty repeatedly.
Because setting the duty will disable PWM and then enable. Delete
this operation now.

Fixes: 211ed630753d2f ("pwm: Add support for Meson PWM Controller")
Signed-off-by: Bichao Zheng <bichao.zheng@xxxxxxxxxxx>
[ Dropped code instead of hiding it behind a comment ]
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>
Reviewed-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
Signed-off-by: Thierry Reding <thierry.reding@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/pwm/pwm-meson.c | 5 -----
1 file changed, 5 deletions(-)

diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
index f58a4867b519..a196439ee14c 100644
--- a/drivers/pwm/pwm-meson.c
+++ b/drivers/pwm/pwm-meson.c
@@ -320,11 +320,6 @@ static int meson_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
if (state->period != channel->state.period ||
state->duty_cycle != channel->state.duty_cycle ||
state->polarity != channel->state.polarity) {
- if (channel->state.enabled) {
- meson_pwm_disable(meson, pwm->hwpwm);
- channel->state.enabled = false;
- }
-
if (state->polarity != channel->state.polarity) {
if (state->polarity == PWM_POLARITY_NORMAL)
meson->inverter_mask |= BIT(pwm->hwpwm);
--
2.20.1