Does Linux on STM32MP support connection of USB hubs and OTG ?

[Pavel A.]

Is the USB controller in MP chips same as in F7 (Tensilica) or compatible?

Does it support connection of devices thru a full speed hub?

Does it support OTG mode?

Thanks,

Pavel A.

[PatrickF]

In STM32MP1, there is two USB controllers with up to three ports with embedded PHY in total:

• a full EHCI/OHCI USB Host controller (acronym: USBH) with 2 High-Speed ports and embedded PHY wich fully support Hub (as example, you have one external Hub on STM32MP1 Discovery and Evaluation boards). This is only a Host controller, and so, does not support OTG.
• an OTG High-Speed controller, similar the the one used on other STM32 MCUs (like STM32H7 series) which support Host or Device mode. Supports OTG (altough now superseded by USB Type-C Dual Role Port. for Type-C, see Discovery board for example, and this post. The OTG IP share one High-Speed PHY with second port of USBH controller or could have dedicated Full-Speed PHY.

Notice that in STM32MP1, our SW delivery support USBH and OTG on Linux (Cortex-A7) only.

[Pavel A.]

Thank you, @PatrickF for the explanation.

-- pa