The LPSS PWM driver calls pwm_lpss_disable() when the PWM device is
released (for example unexported from sysfs). This in turn calls
pm_runtime_put() which makes runtime PM count to be unbalanced if the
device has not been enabled at this point.

This is easy to reproduce:

  # cd /sys/class/pwm/pwmchip0
  # echo 0 > export
  # echo 0 > unexport

The count is unbalanced and prevents the PWM device from being powered on
next time.

Fix this by removing ->free() callback. There are no resources to be
released anyway.

Signed-off-by: Mika Westerberg <[email protected]>
---
 drivers/pwm/pwm-lpss.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/pwm/pwm-lpss.c b/drivers/pwm/pwm-lpss.c
index 6063c3dcbd46..ba9f17443843 100644
--- a/drivers/pwm/pwm-lpss.c
+++ b/drivers/pwm/pwm-lpss.c
@@ -159,7 +159,6 @@ static void pwm_lpss_disable(struct pwm_chip *chip, struct 
pwm_device *pwm)
 }
 
 static const struct pwm_ops pwm_lpss_ops = {
-       .free = pwm_lpss_disable,
        .config = pwm_lpss_config,
        .enable = pwm_lpss_enable,
        .disable = pwm_lpss_disable,
-- 
2.6.2

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