diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index d2c3592..8c748b1 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -236,7 +236,7 @@
 	int ret;
 
 	if (!chip || !chip->dev || !chip->ops || !chip->ops->config ||
-	    !chip->ops->enable || !chip->ops->disable)
+	    !chip->ops->enable || !chip->ops->disable || !chip->npwm)
 		return -EINVAL;
 
 	mutex_lock(&pwm_lock);