linux-kernel - [PATCH v8 4/6] pwm: sun4i: Always calculate params when applying new parameters

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Message-Id: <20191121195902.6906-5-peron.clem@gmail.com>
Date:   Thu, 21 Nov 2019 20:59:00 +0100
From:   Clément Péron <peron.clem@...il.com>
To:     Thierry Reding <thierry.reding@...il.com>,
        Uwe Kleine-König 
        <u.kleine-koenig@...gutronix.de>,
        Maxime Ripard <mripard@...nel.org>,
        Chen-Yu Tsai <wens@...e.org>,
        Philipp Zabel <pza@...gutronix.de>
Cc:     linux-pwm@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-kernel@...r.kernel.org, linux-sunxi@...glegroups.com,
        Clément Péron <peron.clem@...il.com>
Subject: [PATCH v8 4/6] pwm: sun4i: Always calculate params when applying new parameters

Bypass mode will require to be re-calculated when the pwm state
is changed.

Remove the condition so pwm_sun4i_calculate is always called.

Signed-off-by: Clément Péron <peron.clem@...il.com>
---
 drivers/pwm/pwm-sun4i.c | 52 ++++++++++++++++++-----------------------
 1 file changed, 23 insertions(+), 29 deletions(-)

diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c
index 66befd8d6f9c..1fa2057419fb 100644
--- a/drivers/pwm/pwm-sun4i.c
+++ b/drivers/pwm/pwm-sun4i.c
@@ -202,9 +202,9 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 {
 	struct sun4i_pwm_chip *sun4i_pwm = to_sun4i_pwm_chip(chip);
 	struct pwm_state cstate;
-	u32 ctrl;
+	u32 ctrl, duty, period, val;
 	int ret;
-	unsigned int delay_us;
+	unsigned int delay_us, prescaler;
 	unsigned long now;
 
 	pwm_get_state(pwm, &cstate);
@@ -220,43 +220,37 @@ static int sun4i_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 	spin_lock(&sun4i_pwm->ctrl_lock);
 	ctrl = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG);
 
-	if ((cstate.period != state->period) ||
-	    (cstate.duty_cycle != state->duty_cycle)) {
-		u32 period, duty, val;
-		unsigned int prescaler;
-
-		ret = sun4i_pwm_calculate(sun4i_pwm, state,
-					  &duty, &period, &prescaler);
-		if (ret) {
-			dev_err(chip->dev, "period exceeds the maximum value\n");
-			spin_unlock(&sun4i_pwm->ctrl_lock);
-			if (!cstate.enabled)
-				clk_disable_unprepare(sun4i_pwm->clk);
-			return ret;
-		}
-
-		if (PWM_REG_PRESCAL(ctrl, pwm->hwpwm) != prescaler) {
-			/* Prescaler changed, the clock has to be gated */
-			ctrl &= ~BIT_CH(PWM_CLK_GATING, pwm->hwpwm);
-			sun4i_pwm_writel(sun4i_pwm, ctrl, PWM_CTRL_REG);
+	ret = sun4i_pwm_calculate(sun4i_pwm, state, &duty, &period, &prescaler);
+	if (ret) {
+		dev_err(chip->dev, "period exceeds the maximum value\n");
+		spin_unlock(&sun4i_pwm->ctrl_lock);
+		if (!cstate.enabled)
+			clk_disable_unprepare(sun4i_pwm->clk);
+		return ret;
+	}
 
-			ctrl &= ~BIT_CH(PWM_PRESCAL_MASK, pwm->hwpwm);
-			ctrl |= BIT_CH(prescaler, pwm->hwpwm);
-		}
+	if (PWM_REG_PRESCAL(ctrl, pwm->hwpwm) != prescaler) {
+		/* Prescaler changed, the clock has to be gated */
+		ctrl &= ~BIT_CH(PWM_CLK_GATING, pwm->hwpwm);
+		sun4i_pwm_writel(sun4i_pwm, ctrl, PWM_CTRL_REG);
 
-		val = (duty & PWM_DTY_MASK) | PWM_PRD(period);
-		sun4i_pwm_writel(sun4i_pwm, val, PWM_CH_PRD(pwm->hwpwm));
-		sun4i_pwm->next_period[pwm->hwpwm] = jiffies +
-			usecs_to_jiffies(cstate.period / 1000 + 1);
-		sun4i_pwm->needs_delay[pwm->hwpwm] = true;
+		ctrl &= ~BIT_CH(PWM_PRESCAL_MASK, pwm->hwpwm);
+		ctrl |= BIT_CH(prescaler, pwm->hwpwm);
 	}
 
+	val = (duty & PWM_DTY_MASK) | PWM_PRD(period);
+	sun4i_pwm_writel(sun4i_pwm, val, PWM_CH_PRD(pwm->hwpwm));
+	sun4i_pwm->next_period[pwm->hwpwm] = jiffies +
+		usecs_to_jiffies(cstate.period / 1000 + 1);
+	sun4i_pwm->needs_delay[pwm->hwpwm] = true;
+
 	if (state->polarity != PWM_POLARITY_NORMAL)
 		ctrl &= ~BIT_CH(PWM_ACT_STATE, pwm->hwpwm);
 	else
 		ctrl |= BIT_CH(PWM_ACT_STATE, pwm->hwpwm);
 
 	ctrl |= BIT_CH(PWM_CLK_GATING, pwm->hwpwm);
+
 	if (state->enabled) {
 		ctrl |= BIT_CH(PWM_EN, pwm->hwpwm);
 	} else if (!sun4i_pwm->needs_delay[pwm->hwpwm]) {
-- 
2.20.1