Seems like my TinyRex can't change USB0 from USB-OTG to USB-HOST

[eugene128]

Hello. I've got a little trouble.
I have USB-Storage (It has own power supply) and it doesn't eat power from USB, only two data channels is connected, and OTG_ID channel is shorted with GND.

When I'm in uBoot of Openrex, it seeing my USB Storage (connected to USB0) without any troubles.

When I'm in uBoot of TinyRex, which connected to custom board, it doesn't see my USB Strorage (connected to USB0).

But both of data channels and OTG_ID are connected right, because I can boot through USB-OTG into TinyRex's uBoot.

Is there any other sing, which tells to TinyRex state of USB0 (OTG or HOST), or only OTG_ID is needed?

Thanks!

[robertferanec]

Is also GND connected?

[eugene128]

Yes, GND on the USB0 is already connected

[robertferanec]

I do not remember exactly, but I think, there is also something in software what needs to be enabled to support OTG. Do you use your own Kernel?

[eugene128]

No, I'm trying to boot standard Voipa's uBoot through mfgtools.

When I'm on uBoot (loaded through USB-OTG) there is two situations:

OpenRex (works perfect):
* I've turned power OFF of USB0 (5V) manually
* I've succesfully have booted into uBoot through USB-OTG and tool mfgtool2
* I've disconnected USB-OTG cable (it was connected to USB0, default USB-OTG port)
* Then I've plugged in usb-storage into USB0 (via Samsung USB-Connector)
* device has shorted OTG_ID to GND automatically, so I can see mass-storage on USB0

TinyRex:
* I've turned power OFF of USB0 (5V) manually
* I've succesfully have booted into uBoot through USB-OTG and tool mfgtool2
* I've disconnected USB-OTG cable (it was connected to USB0, default USB-OTG port)
* Then I've plugged in usb-storage into USB0 (via Samsung USB-Connector)
* device has shorted OTG_ID to GND automatically (I see it on my osciloscope)
* I've turned power ON of USB0 (5V) manually (I see power level of USB0 on my oscilloscope)
* I still can't see any devices on USB.
Command "usb reset" was excepted with message "Port USB0 is not available."

So, there is connected PINs:
GND (straight connection PIN2PIN)
DATA0 (straight connection PIN2PIN)
DATA1 (straight connection PIN2PIN)
PWR 5V0 (connection through jumper to ON and OFF power manually)
OTG_ID (straight connection PIN2PIN)

[robertferanec]

Check if TinyRex uBoot code has support for otg, looks like there needs to be something added e.g. I found at least this https://github.com/FEDEVEL/openrex-u...9af9c4134a67c3

Is OTG working ok in Linux?

[eugene128]

OTG mode works perfect in Linux and uBoot (I think).

My problem that it doesn't switch to HOST mode on TinyRex (when it needed, for example to read external memory stick), but in that time works fine on OpenRex.

In both cases (TinyRex and OpenRex) I've tried to use original Voipac's U-Boot, without any modifications.

[robertferanec]

Are you using original VOIPAC board with TinyRex module or your own baseboard?

[eugene128]

I'm using own board and USB0 have "pin to pin" connection with micro USB socket.

[robertferanec]

There is power delivery tight up to using OTG. Here you can see it in the schematic (page 9): https://www.imx6rex.com/wp-content/u...-Schematic.pdf

[eugene128]

Well, we've just tried with another TinyRex (serial number 00076) and it works fine.
Looks like something wrong with our first tinyrex 00018.

[robertferanec]

Perfect. Thank you for letting me know.