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    SubjectRe: [PWM PATCH 1/7] API to consolidate PWM devices behind a common user and kernel interface
    H Hartley Sweeten wrote:
    >> +int pwm_set_polarity(struct pwm_channel *p,
    >> + int active_high)
    >> +{
    >> + struct pwm_channel_config c = {
    >> + .config_mask = PWM_CONFIG_POLARITY,
    >> + .polarity = active_high,
    >> + };
    >> + return pwm_config(p, &c);
    >> +}
    >> +EXPORT_SYMBOL(pwm_set_polarity);
    >>
    >
    > Has the 'polarity' logic been verified?
    >
    > pwm_set_polarity takes an active high flag that is passed to pwm_config.
    > A write to the sysfs 'polarity' file passes the value directly to pwm_config.
    > A read from the sysfs 'polarity' file returns struct pwm_channel ->active_low.
    >
    > Seems like a mis-match in logic.
    >

    It was. And on top of that, none of the drivers were reflecting their
    polarity in their pwm_channel structures.

    I renamed the channel structure variable to active_high for consistency,
    and updated each of the drivers to set that value consistent with their
    actual polarities.

    Very good catch.



    b.g.

    --
    Bill Gatliff
    Embedded systems training and consulting
    http://billgatliff.com
    bgat@billgatliff.com



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