Zephyr and stmicro

STMicro has a particular HAL hierarchy of files ported to Zephyr, developed in times likely before and or outside of Zephyr integrations on the part of STMicro. Pinmux files are tricky to navigate when looking for which peripherals are attachable to which pins. Here in dts excerpt channels of timer1 may be attached to GPIO pins of port B:

$workspace/modules/hal/stm32/dts/st/f0/stm32f091rcyx-pinctrl.dtsi

668                         /omit-if-no-ref/ tim1_ch1n_pb13: tim1_ch1n_pb13 {
669                                 pinmux = <STM32_PINMUX('B', 13, AF2)>;
670                         };
671 
672                         /omit-if-no-ref/ tim1_ch2n_pb14: tim1_ch2n_pb14 {
673                                 pinmux = <STM32_PINMUX('B', 14, AF2)>;
674                         };
675 
676                         /omit-if-no-ref/ tim1_ch3n_pb15: tim1_ch3n_pb15 {
677                                 pinmux = <STM32_PINMUX('B', 15, AF2)>;
678                         };

PWM article by Mark Zachmann:

• Using a PWM Device in Zephyr. Using devices in Zephyr is tricky… | by Mark Zachmann | Home Wireless | Medium