STM32MP15x PWM with DMA

RBerk.1 · ‎2024-05-27

Hi,

I am using a STM32MP151AAA3 and i need to control an RGB LED via PWM control (something like the WS2812B). I was looking into the PWM driver options for Linux side control and can't find options for PWM control for specific buffer sizes or anything like that (only for fixed PWM outputs).

On the bare metal MCU's i can control this via PWM and DMA and send a specified data buffer. does anyone know if there is a similar option for a Linux controller PWM driver?

The other option is to control these LED's via the secondary M4 core but I rather not if possible.

Kind regards,

Richard

RBerk.1 · ‎2024-06-02

Hi Olivier,

Thank you for your reply.

After some internet searches i read on a few places that buffer PWM writes are a real hassle or just won't work under Linux. Our solution also due to time constraints was to replace the WS2812B LED's with 'normal' RGB LED's with 3 pin control via an I2C IO extender.

So not really an answer to this question but a fix around the problem.

Richard

View solution in original post

Olivier GALLIEN · ‎2024-05-31

Hi @RBerk.1

Please have a look to PWM overview - stm32mpu

Hope it help

Olivier

Olivier GALLIEN
In order to give better visibility on the answered topics, please click on 'Accept as Solution' on the reply which solved your issue or answered your question.

RBerk.1 · ‎2024-06-02

Hi Olivier,

Thank you for your reply.

After some internet searches i read on a few places that buffer PWM writes are a real hassle or just won't work under Linux. Our solution also due to time constraints was to replace the WS2812B LED's with 'normal' RGB LED's with 3 pin control via an I2C IO extender.

So not really an answer to this question but a fix around the problem.

Richard