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    SubjectRe: [v2 2/2] pwm: Add Aspeed ast2600 PWM support
    Hello,

    your second reply is nearly identical to the first. It would be helpful
    to only write new stuff in new mail. I think there is only a single new
    paragraph that I will reply to here.

    On Mon, May 03, 2021 at 05:57:23AM +0000, Billy Tsai wrote:
    > On 2021/4/27, 4:44 AM,Uwe Kleine-Königwrote:
    > > Also please round down in the division to never provide a duty_cycle
    > > bigger than the requested vaule. Also you have to use the actually used
    > > period as divider, not state->period.
    >
    > I don’t think that I should use the actually used period as divider.
    > The state->duty_cycle is relative with state->period, not the actual period
    > if I use the actual period the precision of the duty cycle may lose.

    The strategy you should implement in .apply() is: Pick the biggest
    period that is not bigger than the requested period. With that period
    pick the biggest duty_cycle that is not bigger than the requested
    duty_cycle.

    As the actual period might be smaller than state->period, dividing by
    the latter yields a result that might be too small.

    See commit 8035e6c66a5e98f098edf7441667de74affb4e78 (currently in next)
    for a similar example.

    Best regards
    Uwe

    --
    Pengutronix e.K. | Uwe Kleine-König |
    Industrial Linux Solutions | https://www.pengutronix.de/ |
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