[PATCH AUTOSEL 4.14 198/371] pwm: meson: Consider 128 a valid pre-divider

[PATCH AUTOSEL 4.14 198/371] pwm: meson: Consider 128 a valid pre-divider

[Sasha Levin]

From: Martin Blumenstingl <martin.blumenstingl@googlemail.com>

[ Upstream commit 51496e4446875726d50a5617a6e0e0dabbc2e6da ]

The pre-divider allows configuring longer PWM periods compared to using
the input clock directly. The pre-divider is 7 bit wide, meaning it's
maximum value is 128 (the register value is off-by-one: 0x7f or 127).

Change the loop to also allow for the maximum possible value to be
considered valid.

Fixes: 211ed630753d2f ("pwm: Add support for Meson PWM Controller")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/pwm/pwm-meson.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
index 9b79cbc7a715..9551f896dd6f 100644
--- a/drivers/pwm/pwm-meson.c
+++ b/drivers/pwm/pwm-meson.c
@@ -188,7 +188,7 @@ static int meson_pwm_calc(struct meson_pwm *meson,
 	do_div(fin_ps, fin_freq);
 
 	/* Calc pre_div with the period */
-	for (pre_div = 0; pre_div < MISC_CLK_DIV_MASK; pre_div++) {
+	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",
@@ -197,7 +197,7 @@ static int meson_pwm_calc(struct meson_pwm *meson,
 			break;
 	}
 
-	if (pre_div == MISC_CLK_DIV_MASK) {
+	if (pre_div > MISC_CLK_DIV_MASK) {
 		dev_err(meson->chip.dev, "unable to get period pre_div\n");
 		return -EINVAL;
 	}
-- 
2.20.1


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[PATCH AUTOSEL 4.14 199/371] pwm: meson: Don't disable PWM when setting duty repeatedly

[Sasha Levin]

From: Bichao Zheng <bichao.zheng@amlogic.com>

[ 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@amlogic.com>
[ Dropped code instead of hiding it behind a comment ]
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 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 9551f896dd6f..3d2c36963a4f 100644
--- a/drivers/pwm/pwm-meson.c
+++ b/drivers/pwm/pwm-meson.c
@@ -325,11 +325,6 @@ 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