pwm: Add the pwm_is_enabled() helper

Some PWM drivers are testing the PWMF_ENABLED flag. Create a helper
function to hide the logic behind enabled test. This will allow us to
smoothly move from the current approach to an atomic PWM update
approach.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

drivers/pwm/core.c

@@ -455,7 +455,7 @@ int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity)
 	if (!pwm->chip->ops->set_polarity)
 		return -ENOSYS;
 
-	if (test_bit(PWMF_ENABLED, &pwm->flags))
+	if (pwm_is_enabled(pwm))
 		return -EBUSY;
 
 	err = pwm->chip->ops->set_polarity(pwm->chip, pwm, polarity);
@@ -853,7 +853,7 @@ static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s)
 		if (test_bit(PWMF_REQUESTED, &pwm->flags))
 			seq_puts(s, " requested");
 
-		if (test_bit(PWMF_ENABLED, &pwm->flags))
+		if (pwm_is_enabled(pwm))
 			seq_puts(s, " enabled");
 
 		seq_puts(s, "\n");

drivers/pwm/pwm-atmel-tcb.c

@@ -347,7 +347,7 @@ static int atmel_tcb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	tcbpwm->duty = duty;
 
 	/* If the PWM is enabled, call enable to apply the new conf */
-	if (test_bit(PWMF_ENABLED, &pwm->flags))
+	if (pwm_is_enabled(pwm))
 		atmel_tcb_pwm_enable(chip, pwm);
 
 	return 0;

drivers/pwm/pwm-atmel.c

@@ -114,7 +114,7 @@ static int atmel_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	u32 val;
 	int ret;
 
-	if (test_bit(PWMF_ENABLED, &pwm->flags) && (period_ns != pwm->period)) {
+	if (pwm_is_enabled(pwm) && (period_ns != pwm->period)) {
 		dev_err(chip->dev, "cannot change PWM period while enabled\n");
 		return -EBUSY;
 	}
@@ -176,7 +176,7 @@ static void atmel_pwm_config_v1(struct pwm_chip *chip, struct pwm_device *pwm,
 	 * If the PWM channel is enabled, only update CDTY by using the update
 	 * register, it needs to set bit 10 of CMR to 0
 	 */
-	if (test_bit(PWMF_ENABLED, &pwm->flags))
+	if (pwm_is_enabled(pwm))
 		return;
 	/*
 	 * If the PWM channel is disabled, write value to duty and period
@@ -191,7 +191,7 @@ static void atmel_pwm_config_v2(struct pwm_chip *chip, struct pwm_device *pwm,
 {
 	struct atmel_pwm_chip *atmel_pwm = to_atmel_pwm_chip(chip);
 
-	if (test_bit(PWMF_ENABLED, &pwm->flags)) {
+	if (pwm_is_enabled(pwm)) {
 		/*
 		 * If the PWM channel is enabled, using the duty update register
 		 * to update the value.

drivers/pwm/pwm-bcm-kona.c

@@ -134,7 +134,7 @@ static int kona_pwmc_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	}
 
 	/* If the PWM channel is enabled, write the settings to the HW */
-	if (test_bit(PWMF_ENABLED, &pwm->flags)) {
+	if (pwm_is_enabled(pwm)) {
 		value = readl(kp->base + PRESCALE_OFFSET);
 		value &= ~PRESCALE_MASK(chan);
 		value |= prescale << PRESCALE_SHIFT(chan);
@@ -287,7 +287,7 @@ static int kona_pwmc_remove(struct platform_device *pdev)
 	unsigned int chan;
 
 	for (chan = 0; chan < kp->chip.npwm; chan++)
-		if (test_bit(PWMF_ENABLED, &kp->chip.pwms[chan].flags))
+		if (pwm_is_enabled(&kp->chip.pwms[chan]))
 			clk_disable_unprepare(kp->clk);
 
 	return pwmchip_remove(&kp->chip);

drivers/pwm/pwm-ep93xx.c

@@ -82,7 +82,7 @@ static int ep93xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	 * The clock needs to be enabled to access the PWM registers.
 	 * Configuration can be changed at any time.
 	 */
-	if (!test_bit(PWMF_ENABLED, &pwm->flags)) {
+	if (!pwm_is_enabled(pwm)) {
 		ret = clk_enable(ep93xx_pwm->clk);
 		if (ret)
 			return ret;
@@ -113,7 +113,7 @@ static int ep93xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 		ret = -EINVAL;
 	}
 
-	if (!test_bit(PWMF_ENABLED, &pwm->flags))
+	if (!pwm_is_enabled(pwm))
 		clk_disable(ep93xx_pwm->clk);
 
 	return ret;

drivers/pwm/pwm-imx.c

@@ -114,7 +114,7 @@ static int imx_pwm_config_v2(struct pwm_chip *chip,
 	unsigned long long c;
 	unsigned long period_cycles, duty_cycles, prescale;
 	unsigned int period_ms;
-	bool enable = test_bit(PWMF_ENABLED, &pwm->flags);
+	bool enable = pwm_is_enabled(pwm);
 	int wait_count = 0, fifoav;
 	u32 cr, sr;
 

drivers/pwm/pwm-mxs.c

@@ -77,7 +77,7 @@ static int mxs_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	 * If the PWM channel is disabled, make sure to turn on the clock
 	 * before writing the register. Otherwise, keep it enabled.
 	 */
-	if (!test_bit(PWMF_ENABLED, &pwm->flags)) {
+	if (!pwm_is_enabled(pwm)) {
 		ret = clk_prepare_enable(mxs->clk);
 		if (ret)
 			return ret;
@@ -92,7 +92,7 @@ static int mxs_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	/*
 	 * If the PWM is not enabled, turn the clock off again to save power.
 	 */
-	if (!test_bit(PWMF_ENABLED, &pwm->flags))
+	if (!pwm_is_enabled(pwm))
 		clk_disable_unprepare(mxs->clk);
 
 	return 0;

drivers/pwm/pwm-renesas-tpu.c

@@ -301,7 +301,7 @@ static int tpu_pwm_config(struct pwm_chip *chip, struct pwm_device *_pwm,
 	pwm->duty = duty;
 
 	/* If the channel is disabled we're done. */
-	if (!test_bit(PWMF_ENABLED, &_pwm->flags))
+	if (!pwm_is_enabled(_pwm))
 		return 0;
 
 	if (duty_only && pwm->timer_on) {

drivers/pwm/pwm-tegra.c

@@ -112,7 +112,7 @@ static int tegra_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	 * If the PWM channel is disabled, make sure to turn on the clock
 	 * before writing the register. Otherwise, keep it enabled.
 	 */
-	if (!test_bit(PWMF_ENABLED, &pwm->flags)) {
+	if (!pwm_is_enabled(pwm)) {
 		err = clk_prepare_enable(pc->clk);
 		if (err < 0)
 			return err;
@@ -124,7 +124,7 @@ static int tegra_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 	/*
 	 * If the PWM is not enabled, turn the clock off again to save power.
 	 */
-	if (!test_bit(PWMF_ENABLED, &pwm->flags))
+	if (!pwm_is_enabled(pwm))
 		clk_disable_unprepare(pc->clk);
 
 	return 0;
@@ -214,7 +214,7 @@ static int tegra_pwm_remove(struct platform_device *pdev)
 	for (i = 0; i < NUM_PWM; i++) {
 		struct pwm_device *pwm = &pc->chip.pwms[i];
 
-		if (!test_bit(PWMF_ENABLED, &pwm->flags))
+		if (!pwm_is_enabled(pwm))
 			if (clk_prepare_enable(pc->clk) < 0)
 				continue;
 

drivers/pwm/pwm-tiecap.c

@@ -97,7 +97,7 @@ static int ecap_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 
 	writew(reg_val, pc->mmio_base + ECCTL2);
 
-	if (!test_bit(PWMF_ENABLED, &pwm->flags)) {
+	if (!pwm_is_enabled(pwm)) {
 		/* Update active registers if not running */
 		writel(duty_cycles, pc->mmio_base + CAP2);
 		writel(period_cycles, pc->mmio_base + CAP1);
@@ -111,7 +111,7 @@ static int ecap_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
 		writel(period_cycles, pc->mmio_base + CAP3);
 	}
 
-	if (!test_bit(PWMF_ENABLED, &pwm->flags)) {
+	if (!pwm_is_enabled(pwm)) {
 		reg_val = readw(pc->mmio_base + ECCTL2);
 		/* Disable APWM mode to put APWM output Low */
 		reg_val &= ~ECCTL2_APWM_MODE;
@@ -179,7 +179,7 @@ static void ecap_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
 
 static void ecap_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
 {
-	if (test_bit(PWMF_ENABLED, &pwm->flags)) {
+	if (pwm_is_enabled(pwm)) {
 		dev_warn(chip->dev, "Removing PWM device without disabling\n");
 		pm_runtime_put_sync(chip->dev);
 	}
@@ -306,7 +306,7 @@ static int ecap_pwm_suspend(struct device *dev)
 	ecap_pwm_save_context(pc);
 
 	/* Disable explicitly if PWM is running */
-	if (test_bit(PWMF_ENABLED, &pwm->flags))
+	if (pwm_is_enabled(pwm))
 		pm_runtime_put_sync(dev);
 
 	return 0;
@@ -318,7 +318,7 @@ static int ecap_pwm_resume(struct device *dev)
 	struct pwm_device *pwm = pc->chip.pwms;
 
 	/* Enable explicitly if PWM was running */
-	if (test_bit(PWMF_ENABLED, &pwm->flags))
+	if (pwm_is_enabled(pwm))
 		pm_runtime_get_sync(dev);
 
 	ecap_pwm_restore_context(pc);

drivers/pwm/pwm-tiehrpwm.c

@@ -407,7 +407,7 @@ static void ehrpwm_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
 {
 	struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
 
-	if (test_bit(PWMF_ENABLED, &pwm->flags)) {
+	if (pwm_is_enabled(pwm)) {
 		dev_warn(chip->dev, "Removing PWM device without disabling\n");
 		pm_runtime_put_sync(chip->dev);
 	}
@@ -565,7 +565,7 @@ static int ehrpwm_pwm_suspend(struct device *dev)
 	for (i = 0; i < pc->chip.npwm; i++) {
 		struct pwm_device *pwm = &pc->chip.pwms[i];
 
-		if (!test_bit(PWMF_ENABLED, &pwm->flags))
+		if (!pwm_is_enabled(pwm))
 			continue;
 
 		/* Disable explicitly if PWM is running */
@@ -582,7 +582,7 @@ static int ehrpwm_pwm_resume(struct device *dev)
 	for (i = 0; i < pc->chip.npwm; i++) {
 		struct pwm_device *pwm = &pc->chip.pwms[i];
 
-		if (!test_bit(PWMF_ENABLED, &pwm->flags))
+		if (!pwm_is_enabled(pwm))
 			continue;
 
 		/* Enable explicitly if PWM was running */

drivers/pwm/sysfs.c

@@ -97,7 +97,7 @@ static ssize_t pwm_enable_show(struct device *child,
 			       char *buf)
 {
 	const struct pwm_device *pwm = child_to_pwm_device(child);
-	int enabled = test_bit(PWMF_ENABLED, &pwm->flags);
+	int enabled = pwm_is_enabled(pwm);
 
 	return sprintf(buf, "%d\n", enabled);
 }

include/linux/pwm.h

@@ -92,6 +92,11 @@ struct pwm_device {
 	enum pwm_polarity	polarity;
 };
 
+static inline bool pwm_is_enabled(const struct pwm_device *pwm)
+{
+	return test_bit(PWMF_ENABLED, &pwm->flags);
+}
+
 static inline void pwm_set_period(struct pwm_device *pwm, unsigned int period)
 {
 	if (pwm)