gpio: mvebu/pwm: Refuse requests with inverted polarity

[ Upstream commit 3ecb10175b1f776f076553c24e2689e42953fef5 ]

The driver doesn't take struct pwm_state::polarity into account when
configuring the hardware, so refuse requests for inverted polarity.

Fixes: 757642f9a584 ("gpio: mvebu: Add limited PWM support")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c
index ad8822d..1448dc8 100644 (file)
--- a/drivers/gpio/gpio-mvebu.c
+++ b/drivers/gpio/gpio-mvebu.c
@@ -707,6 +707,9 @@ static int mvebu_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
        unsigned long flags;
        unsigned int on, off;
 
+       if (state->polarity != PWM_POLARITY_NORMAL)
+               return -EINVAL;
+
        val = (unsigned long long) mvpwm->clk_rate * state->duty_cycle;
        do_div(val, NSEC_PER_SEC);
        if (val > UINT_MAX + 1ULL)