pwm: atmel: Drop driver local locking

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 <[e-mail]>
Link: https://lore.kernel.org/r/5ad3417[e-mail]
Signed-off-by: Uwe Kleine-König <[e-mail]>

drivers/pwm/pwm-atmel.c

···
 	 * hardware.
 	 */
 	u32 update_pending;
-
-	/* Protects .update_pending */
-	spinlock_t lock;
 };
 
 static inline struct atmel_pwm_chip *to_atmel_pwm_chip(struct 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.
···
 	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);
···
 		if (chip->update_pending & (1 << ch))
 			ret = 1;
 	}
-
-	spin_unlock(&chip->lock);
 
 	return ret;
 }
···
 	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))