linux-kernel - [PATCH v3 05/14] pwm: meson: don't duplicate the polarity internally

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Message-Id: <20190612195911.4442-6-martin.blumenstingl@googlemail.com>
Date:   Wed, 12 Jun 2019 21:59:02 +0200
From:   Martin Blumenstingl <martin.blumenstingl@...glemail.com>
To:     linux-amlogic@...ts.infradead.org, linux-pwm@...r.kernel.org,
        thierry.reding@...il.com
Cc:     linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        u.kleine-koenig@...gutronix.de, narmstrong@...libre.com,
        Martin Blumenstingl <martin.blumenstingl@...glemail.com>
Subject: [PATCH v3 05/14] pwm: meson: don't duplicate the polarity internally

Let meson_pwm_calc() use the polarity from struct pwm_state directly.
This removes a level of indirection where meson_pwm_apply() first had to
set a driver-internal inverter mask which was then only used by
meson_pwm_calc().

Instead of adding the polarity as parameter to meson_pwm_calc() switch
to struct pwm_state directly to make it easier to see where the
parameters are actually coming from.

Reviewed-by: Neil Armstrong <narmstrong@...libre.com>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@...glemail.com>
---
 drivers/pwm/pwm-meson.c | 23 ++++++++---------------
 1 file changed, 8 insertions(+), 15 deletions(-)

diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
index 84b28ba0f903..39ea119add7b 100644
--- a/drivers/pwm/pwm-meson.c
+++ b/drivers/pwm/pwm-meson.c
@@ -63,7 +63,6 @@ struct meson_pwm {
 	struct pwm_chip chip;
 	const struct meson_pwm_data *data;
 	void __iomem *base;
-	u8 inverter_mask;
 	/*
 	 * Protects register (write) access to the REG_MISC_AB register
 	 * that is shared between the two PWMs.
@@ -116,14 +115,17 @@ static void meson_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
 }
 
 static int meson_pwm_calc(struct meson_pwm *meson,
-			  struct meson_pwm_channel *channel, unsigned int id,
-			  unsigned int duty, unsigned int period)
+			  struct meson_pwm_channel *channel,
+			  struct pwm_state *state)
 {
-	unsigned int pre_div, cnt, duty_cnt;
+	unsigned int duty, period, pre_div, cnt, duty_cnt;
 	unsigned long fin_freq = -1;
 	u64 fin_ps;
 
-	if (~(meson->inverter_mask >> id) & 0x1)
+	duty = state->duty_cycle;
+	period = state->period;
+
+	if (state->polarity == PWM_POLARITY_INVERSED)
 		duty = period - duty;
 
 	if (period == channel->state.period &&
@@ -278,15 +280,7 @@ 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 (state->polarity != channel->state.polarity) {
-			if (state->polarity == PWM_POLARITY_NORMAL)
-				meson->inverter_mask |= BIT(pwm->hwpwm);
-			else
-				meson->inverter_mask &= ~BIT(pwm->hwpwm);
-		}
-
-		err = meson_pwm_calc(meson, channel, pwm->hwpwm,
-				     state->duty_cycle, state->period);
+		err = meson_pwm_calc(meson, channel, state);
 		if (err < 0)
 			return err;
 
@@ -520,7 +514,6 @@ static int meson_pwm_probe(struct platform_device *pdev)
 	meson->chip.of_pwm_n_cells = 3;
 
 	meson->data = of_device_get_match_data(&pdev->dev);
-	meson->inverter_mask = BIT(meson->chip.npwm) - 1;
 
 	channels = devm_kcalloc(&pdev->dev, meson->chip.npwm,
 				sizeof(*channels), GFP_KERNEL);
-- 
2.22.0