Use USB microB for USB peripherals rather than power on BRK

[mlarkin]

Hello,

I am trying to power the BRK from breakout pins (this works). We removed the ferrite bead and are providing power to VIN.

We have a USB stick attached via a micro-B to female usb-A cable, the device does not show up to Linux.

We have confirmed the USB is getting power and we removed the small section of usb_otg in the device tree.

Is there any other reason this might not work?

Appreciate the help.

[Neeraj Dantu]

mlarkin,

The BRK’s micro-USB is not setup to function as host. Please take a look at the requirements in section 10.1.12 (USB) of the hardware getting started guide for STM32MP1 (https://www.st.com/resource/en/application_note/dm00389996-getting-started-with-stm32mp151-stm32mp153-and-stm32mp157-line-hardware-development-stmicroelectronics.pdf).

You can use the dedicated Host USB pins provided on PB29 and PB30 Header pins(https://octavosystems.com/docs/osd32mp1-brk-schematics/). You can use a USB Type A breakout (https://learn.sparkfun.com/tutorials/usb-type-a-female-breakout-hookup-guide/all) to implement a USB host port. You will not need to make a device tree change.

Best,

Neeraj

[mlarkin]

Thank you for the insight.

We need 2 USB host ports. We are actually already using the port off of PB29/30 with the sparkfun breakout exactly as you mentioned and it works great.

Looking at section 10.1.12, is the OTG block the micro-USB on the BRK? I think it is.

It looks like second port from the usb is not brought out on the BRK.

Is there anyway to use the OTG port as a host?

In the document, “Note: On OTG IP, USB full-speed device is also supported by using Micro-B receptacle instead of Micro-AB and leaving the OTG_ID pin unconnected.” We did precisely this and had the ID pin floating, but saw no change.

[Neeraj Dantu]

mlarkin,

Your best bet is to use a USB hub connected to the USB host port you are using.

In order to use the OTG port as host, the ID pin must be connected to GND or to the USB port for the USB peripheral to detect the host configuration. For device configuration, this is not necessary(ID pin can be left floating).

Best,

Neeraj

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