[PATCH 3/5] pwm: stm32: Use hweight32 in stm32_pwm_detect_channels

Uwe Kleine-König u.kleine-koenig at pengutronix.de
Thu Oct 19 13:07:02 PDT 2023


From: Philipp Zabel <p.zabel at pengutronix.de>

Use hweight32() to count the CCxE bits in stm32_pwm_detect_channels().
Since the return value is assigned to chip.npwm, change it to unsigned
int as well.

Signed-off-by: Philipp Zabel <p.zabel at pengutronix.de>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig at pengutronix.de>
---
 drivers/pwm/pwm-stm32.c | 17 ++---------------
 1 file changed, 2 insertions(+), 15 deletions(-)

diff --git a/drivers/pwm/pwm-stm32.c b/drivers/pwm/pwm-stm32.c
index 009f9c1a5eca..cc6cae07c02c 100644
--- a/drivers/pwm/pwm-stm32.c
+++ b/drivers/pwm/pwm-stm32.c
@@ -563,10 +563,9 @@ static void stm32_pwm_detect_complementary(struct stm32_pwm *priv)
 	priv->have_complementary_output = (ccer != 0);
 }
 
-static int stm32_pwm_detect_channels(struct stm32_pwm *priv)
+static unsigned int stm32_pwm_detect_channels(struct stm32_pwm *priv)
 {
 	u32 ccer;
-	int npwm = 0;
 
 	/*
 	 * If channels enable bits don't exist writing 1 will have no
@@ -576,19 +575,7 @@ static int stm32_pwm_detect_channels(struct stm32_pwm *priv)
 	regmap_read(priv->regmap, TIM_CCER, &ccer);
 	regmap_clear_bits(priv->regmap, TIM_CCER, TIM_CCER_CCXE);
 
-	if (ccer & TIM_CCER_CC1E)
-		npwm++;
-
-	if (ccer & TIM_CCER_CC2E)
-		npwm++;
-
-	if (ccer & TIM_CCER_CC3E)
-		npwm++;
-
-	if (ccer & TIM_CCER_CC4E)
-		npwm++;
-
-	return npwm;
+	return hweight32(ccer & TIM_CCER_CCXE);
 }
 
 static int stm32_pwm_probe(struct platform_device *pdev)
-- 
2.42.0




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