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BC1.2 together with USB_HS



I am working on a rechargeable battery powered device that includes a STM32F405VGT6 and can communicate with a proprietary PC software using the internal USB HS Phy.

To control the charging of the battery I included a BQ IC (BQ25882), this IC includes D+/- detection to implement BC1.2 DCD.

I seem to have problems with the STM32F4 and the BQ living together on the same USB port. When the STM32F4's USB Phy (with its internal DP PU) is physically connected to the port - the DCD on the BQ is not preforming correctly. From my understanding this is due to the DP PU that interferes with the resistor divider.

This seems like a common requirement for a device but I cant find any information about how to do this correctly. I may be missing something.

If it matters - the STM32F4 is not connected to VBUS and not sensing it.

Does anyone have any tips about including these two together?