Re: [PATCH 1/4] pwm: pca9685: remove unused duty_cycle struct element

Uwe Kleine-König
2020-02-26T15:10:38Z

Hello Matthias,

as you seem to have this hardware on your desk, it would be great if you
could answer the following questions:

- Does the hardware complete the currently running period before
applying a new setting?
- Is this racy somehow (i.e. can it happen that when going from
duty_cycle/period = 1000/5000 to duty_cycle/period = 4000/10000 the
output is 1000/10000 (or 4000/5000) for one cycle)?
- Does the hardware complete the currently running period before
.enabled = false is configured?
- How does the output pin behave on a disabled PWM. (Usual candidates
are: freeze where is just happens to be, constant inactive and
High-Z).

Best regards
Uwe

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