Re: [PATCH v5 3/6] pwm: Add rockchip PWMv4 driver
From: Damon Ding
Date: Sun Apr 26 2026 - 08:07:49 EST
Hi Nicolas,
On 4/20/2026 9:52 PM, Nicolas Frattaroli wrote:
The Rockchip RK3576 brings with it a new PWM IP, in downstream codeTested-by: Damon Ding <damon.ding@xxxxxxxxxxxxxx>
referred to as "v4". This new IP is different enough from the previous
Rockchip IP that I felt it necessary to add a new driver for it, instead
of shoehorning it in the old one.
Add this new driver, based on the PWM core's waveform APIs. Its platform
device is registered by the parent mfpwm driver, from which it also
receives a little platform data struct, so that mfpwm can guarantee that
all the platform device drivers spread across different subsystems for
this specific hardware IP do not interfere with each other.
Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@xxxxxxxxxxxxx>
The continuous mode of all PWM channels has been preliminarily tested
and verified working on the RK3576 IoT board.
I have tested with several typical period and duty cycle configurations.
Following Uwe's suggestion [0], I also tested with libpwm using commands
similar to the following:
./pwmset -c 0 -p 0 -P 1000000 -D 500000 -s 5000
I was previously unaware of the existence of libpwm. I will continue to follow its upstream development and updates going forward. :-)
Best regards,
Damon
[0]https://lore.kernel.org/all/fgu42esufq2x4fcccncqs3hlotih2gqmws5atotlaznuahoslw@34vblr6vboze/