The datasheet specifies that programming the base_unit part of the
ctrl register to 0 results in a contineous low signal.

Adjust the get_state method to reflect this by setting pwm_state.period
to 1 and duty_cycle to 0.

Suggested-by: Uwe Kleine-König <u.kleine-koe...@pengutronix.de>
Signed-off-by: Hans de Goede <hdego...@redhat.com>
---
Changes in v4:
- This is a new patch in v4 of this patchset
---
 drivers/pwm/pwm-lpss.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/pwm/pwm-lpss.c b/drivers/pwm/pwm-lpss.c
index 4f3d60ce9929..4d4de45cf99b 100644
--- a/drivers/pwm/pwm-lpss.c
+++ b/drivers/pwm/pwm-lpss.c
@@ -192,14 +192,16 @@ static void pwm_lpss_get_state(struct pwm_chip *chip, 
struct pwm_device *pwm,
 
        freq = base_unit * lpwm->info->clk_rate;
        do_div(freq, base_unit_range);
-       if (freq == 0)
-               state->period = NSEC_PER_SEC;
-       else
+       if (freq == 0) {
+               /* In this case the PWM outputs a continous low signal */
+               state->period = 1;
+               state->duty_cycle = 0;
+       } else {
                state->period = NSEC_PER_SEC / (unsigned long)freq;
-
-       on_time_div *= state->period;
-       do_div(on_time_div, 255);
-       state->duty_cycle = on_time_div;
+               on_time_div *= state->period;
+               do_div(on_time_div, 255);
+               state->duty_cycle = on_time_div;
+       }
 
        state->polarity = PWM_POLARITY_NORMAL;
        state->enabled = !!(ctrl & PWM_ENABLE);
-- 
2.26.2

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