diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index dba3843c53b8d2162d10100d2473be79014d4b4b..ed337a8c34ab4bb231814136fe5cd9628962eff1 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -457,7 +457,8 @@ int pwm_apply_state(struct pwm_device *pwm, struct pwm_state *state)
 {
 	int err;
 
-	if (!pwm)
+	if (!pwm || !state || !state->period ||
+	    state->duty_cycle > state->period)
 		return -EINVAL;
 
 	if (!memcmp(state, &pwm->state, sizeof(*state)))
diff --git a/drivers/pwm/pwm-atmel-hlcdc.c b/drivers/pwm/pwm-atmel-hlcdc.c
index f994c7eaf41c6c3d67a0c688247561dadee49863..14fc011faa32fee990c7ab9253d5faabe67465d4 100644
--- a/drivers/pwm/pwm-atmel-hlcdc.c
+++ b/drivers/pwm/pwm-atmel-hlcdc.c
@@ -272,7 +272,7 @@ static int atmel_hlcdc_pwm_probe(struct platform_device *pdev)
 	chip->chip.of_pwm_n_cells = 3;
 	chip->chip.can_sleep = 1;
 
-	ret = pwmchip_add(&chip->chip);
+	ret = pwmchip_add_with_polarity(&chip->chip, PWM_POLARITY_INVERSED);
 	if (ret) {
 		clk_disable_unprepare(hlcdc->periph_clk);
 		return ret;
diff --git a/drivers/pwm/sysfs.c b/drivers/pwm/sysfs.c
index d98599249a05688137325fcf906415e14aa7aed4..01695d48dd543152624b9ed40a9c3afd9de45d0d 100644
--- a/drivers/pwm/sysfs.c
+++ b/drivers/pwm/sysfs.c
@@ -152,7 +152,7 @@ static ssize_t enable_store(struct device *child,
 		goto unlock;
 	}
 
-	pwm_apply_state(pwm, &state);
+	ret = pwm_apply_state(pwm, &state);
 
 unlock:
 	mutex_unlock(&export->lock);
diff --git a/include/linux/pwm.h b/include/linux/pwm.h
index 17018f3c066ed5a44c76ca77ce63b6203725ef34..908b67c847cd656489f0a679422852e7c845d18f 100644
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h
@@ -235,6 +235,9 @@ static inline int pwm_config(struct pwm_device *pwm, int duty_ns,
 	if (!pwm)
 		return -EINVAL;
 
+	if (duty_ns < 0 || period_ns < 0)
+		return -EINVAL;
+
 	pwm_get_state(pwm, &state);
 	if (state.duty_cycle == duty_ns && state.period == period_ns)
 		return 0;