Using internal STPMIC1 boost and power switch for USB dual role functionality.

[Badzonor]

Hello, we have trouble finding any dts example for USB dual role utilizing STPMIC1 internal boost regulator and power switches. Our design is pretty close to attached scheme (from AN5260 page 6).

We need to know how to use stpmic1 linux driver to dynamically start and stop boots regulator and power swich on USB device insertion. We use USB-C witch additional IC but for simplicity just assume oldstyle ID pin and VBUS detection.

Could we get information what we need to do for this functionality to work? Any driver modyfications needs to be done? Maybe theory of operation (linux side)?

Any starting point for further work will be helpful. Thank you!

[PatrickF]

Hi,

please have a look to

https://wiki.st.com/stm32mpu/wiki/OTG_device_tree_configuration#DT_configuration_example_as_high_speed_OTG--with_micro-B_connector--Vbus_and_ID_mapped_on_GPIOs

(note that VBUS GPIO should have a voltage divider as listed in AN4879. STM32MP1 OTG_VBUS pin should be left open)

For STPMIC1 BOOST, I think you should look at https://wiki.st.com/stm32mpu/wiki/Regulator_overview and https://github.com/STMicroelectronics/linux/blob/v6.6-stm32mp/Documentation/devicetree/bindings/mfd/st,stpmic1.yaml

Regards.