[PATCH 1/8] pwm: atmel: Drop driver local locking

Uwe Kleine-König u.kleine-koenig at baylibre.com
Tue Jun 24 11:15:37 PDT 2025


The two functions making use of the lock are only called transitively from
.apply(). Calls to .apply() are already serialized by the pwm core so the
lock in the driver has no effect and can safely be dropped.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig at baylibre.com>
---
 drivers/pwm/pwm-atmel.c | 12 ------------
 1 file changed, 12 deletions(-)

diff --git a/drivers/pwm/pwm-atmel.c b/drivers/pwm/pwm-atmel.c
index b2f0abbbad63..06d22d0f7b26 100644
--- a/drivers/pwm/pwm-atmel.c
+++ b/drivers/pwm/pwm-atmel.c
@@ -91,9 +91,6 @@ struct atmel_pwm_chip {
 	 * hardware.
 	 */
 	u32 update_pending;
-
-	/* Protects .update_pending */
-	spinlock_t lock;
 };
 
 static inline struct atmel_pwm_chip *to_atmel_pwm_chip(struct pwm_chip *chip)
@@ -145,8 +142,6 @@ static void atmel_pwm_update_pending(struct atmel_pwm_chip *chip)
 
 static void atmel_pwm_set_pending(struct atmel_pwm_chip *chip, unsigned int ch)
 {
-	spin_lock(&chip->lock);
-
 	/*
 	 * Clear pending flags in hardware because otherwise there might still
 	 * be a stale flag in ISR.
@@ -154,16 +149,12 @@ static void atmel_pwm_set_pending(struct atmel_pwm_chip *chip, unsigned int ch)
 	atmel_pwm_update_pending(chip);
 
 	chip->update_pending |= (1 << ch);
-
-	spin_unlock(&chip->lock);
 }
 
 static int atmel_pwm_test_pending(struct atmel_pwm_chip *chip, unsigned int ch)
 {
 	int ret = 0;
 
-	spin_lock(&chip->lock);
-
 	if (chip->update_pending & (1 << ch)) {
 		atmel_pwm_update_pending(chip);
 
@@ -171,8 +162,6 @@ static int atmel_pwm_test_pending(struct atmel_pwm_chip *chip, unsigned int ch)
 			ret = 1;
 	}
 
-	spin_unlock(&chip->lock);
-
 	return ret;
 }
 
@@ -509,7 +498,6 @@ static int atmel_pwm_probe(struct platform_device *pdev)
 	atmel_pwm->data = of_device_get_match_data(&pdev->dev);
 
 	atmel_pwm->update_pending = 0;
-	spin_lock_init(&atmel_pwm->lock);
 
 	atmel_pwm->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(atmel_pwm->base))
-- 
2.49.0




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