This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TUSB8041: TUSB8041: linux 4.14 can not recognize TUSB8041

Part Number: TUSB8041

Hi Team

My CTM use TUSB8041 in their system

CTM CPU (LS1043a) is connected to the hub chip TUSB8041 (using the USB2.0 protocol). Currently, the kernel (4.14) on board cannot recognize the chip.

When the kernel starts, it obtains the state of the root hub port connected to the TUSB8041, and there is no PORT_CONNECTION state, which means that the hub chip does not have attatch to the root hub.

The D+ signal of the usb interface on the board hardware is always low. It is estimated that the root hub port cannot detect whether the hub chip is inserted.

Pls see attach file.

On the hardware, it is no problem to measure the clock and power signals on the Hub side. 

Is it necessary to configure the hub chip through SMbus before the kernel can normally recognize and enumerate the hub chip?

Could you check SCH?


  
SCHEMATIC1 _ P12-USB_HUB.pdfSCHEMATIC1 _ P12-USB_HUB.pdf

  • Hello Seasat,

    The hub will wait in configuration mode until the SMBUS host sets the cfgactive bit in the TUSB8041 registers if SMBUSz is pulled low.  If the customer is not using the SMBUS host, they should pull up the SMBUSz line ( or it also has an internal pullup).

    Regards,

    JMMN