Re: [PATCH v1] pwm: add sysfs interface

From: Lars Poeschel
Date: Tue Apr 09 2013 - 05:21:39 EST


On Monday 08 April 2013 at 13:34:58, Thierry Reding wrote:
> By the way, would you mind elaborating a bit on the various use-cases
> that you have? I'm interested in what people use the PWM subsystem for
> and you seem to be the only one currently using it from userspace. I'm
> hoping I can get a better understanding of what the PWM subsystem nedes
> to provide if I know what people use it for.

Sure, but there is not much about it:
The PWM output is connected to an electronic circuit that converts the
signal to a voltage. The higher the duty cycle is the higher the voltage
gets. In fact this is a simple DAC converter. This voltage limits the
electric current a battery recharger uses to charge a battery. We think
controlling the PWM from userspace is a simple way for our application to
control the voltage.
If you have further questions feel free to ask.

Lars
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