Re: How to PWM in RPi3B+

[mlelstv%serpens.de@localhost (Michael van Elst)]

nmingotti%gmail.com@localhost ("Dr. Nicola Mingotti") writes:

>I am able to use GPIOPWM but that is limited to 100 Hz
>so I wish to use the hardware device, if possible.

>I found this old mail showing there was something already
>done but i can't find anything else.
>https://mail-index.netbsd.org/port-arm/2018/04/04/msg004706.html

>If you know how to do it please let me know.


There is currently no working driver for it, and there was never
anything exposed to userland.

The hardware itself can either generate a static PWM signal
with fixed pulse width, it can also be fed from a DMA channel
to produce a sequence of individual pulses.

The PWM hardware is also used for analog audio output. There should be
some mechanism to manage exclusive access.