pwm: atmel: Change prototype of a helper to prepare further changes

This prepares the driver for further changes that will make it harder to
determine the pwm_chip from a given atmel_pwm_chip. To just not have to
do that, rework atmel_pwm_enable_clk_if_on() to take a pwm_chip.

Link: https://lore.kernel.org/r/c9a92f77760e401debfe0c9bfc086222f31fb3c4.1707900770.git.u.kleine-koenig@pengutronix.deSigned-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

drivers/pwm/pwm-atmel.c

@@ -459,8 +459,9 @@ static const struct of_device_id atmel_pwm_dt_ids[] = {
 };
 MODULE_DEVICE_TABLE(of, atmel_pwm_dt_ids);
 
-static int atmel_pwm_enable_clk_if_on(struct atmel_pwm_chip *atmel_pwm, bool on)
+static int atmel_pwm_enable_clk_if_on(struct pwm_chip *chip, bool on)
 {
+	struct atmel_pwm_chip *atmel_pwm = to_atmel_pwm_chip(chip);
 	unsigned int i, cnt = 0;
 	unsigned long sr;
 	int ret = 0;
@@ -469,7 +470,7 @@ static int atmel_pwm_enable_clk_if_on(struct atmel_pwm_chip *atmel_pwm, bool on)
 	if (!sr)
 		return 0;
 
-	cnt = bitmap_weight(&sr, atmel_pwm->chip.npwm);
+	cnt = bitmap_weight(&sr, chip->npwm);
 
 	if (!on)
 		goto disable_clk;
@@ -477,7 +478,7 @@ static int atmel_pwm_enable_clk_if_on(struct atmel_pwm_chip *atmel_pwm, bool on)
 	for (i = 0; i < cnt; i++) {
 		ret = clk_enable(atmel_pwm->clk);
 		if (ret) {
-			dev_err(atmel_pwm->chip.dev,
+			dev_err(chip->dev,
 				"failed to enable clock for pwm %pe\n",
 				ERR_PTR(ret));
 
@@ -498,6 +499,7 @@ static int atmel_pwm_enable_clk_if_on(struct atmel_pwm_chip *atmel_pwm, bool on)
 static int atmel_pwm_probe(struct platform_device *pdev)
 {
 	struct atmel_pwm_chip *atmel_pwm;
+	struct pwm_chip *chip;
 	int ret;
 
 	atmel_pwm = devm_kzalloc(&pdev->dev, sizeof(*atmel_pwm), GFP_KERNEL);
@@ -518,15 +520,16 @@ static int atmel_pwm_probe(struct platform_device *pdev)
 		return dev_err_probe(&pdev->dev, PTR_ERR(atmel_pwm->clk),
 				     "failed to get prepared PWM clock\n");
 
-	atmel_pwm->chip.dev = &pdev->dev;
-	atmel_pwm->chip.ops = &atmel_pwm_ops;
-	atmel_pwm->chip.npwm = 4;
+	chip = &atmel_pwm->chip;
+	chip->dev = &pdev->dev;
+	chip->ops = &atmel_pwm_ops;
+	chip->npwm = 4;
 
-	ret = atmel_pwm_enable_clk_if_on(atmel_pwm, true);
+	ret = atmel_pwm_enable_clk_if_on(chip, true);
 	if (ret < 0)
 		return ret;
 
-	ret = devm_pwmchip_add(&pdev->dev, &atmel_pwm->chip);
+	ret = devm_pwmchip_add(&pdev->dev, chip);
 	if (ret < 0) {
 		dev_err_probe(&pdev->dev, ret, "failed to add PWM chip\n");
 		goto disable_clk;
@@ -535,7 +538,7 @@ static int atmel_pwm_probe(struct platform_device *pdev)
 	return 0;
 
 disable_clk:
-	atmel_pwm_enable_clk_if_on(atmel_pwm, false);
+	atmel_pwm_enable_clk_if_on(chip, false);
 
 	return ret;
 }