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Sgs USB Host Debug SOP Manual

REVISION HISTORY

Revision No.
Description
 Date
1.0
  • Initial release
    		•  12/03/2024

    Issue 1. Device Not Recognized

    Figure 1 Device Recognition Troubleshooting Flowchart
    Step Method
    A The log level may be too low to display USB enumeration logs. Execute echo 7 > /proc/sys/kernel/printk to increase the log level
    B USB 2.0 host requires the following kernel modules: ehci-hcd.ko, sgs-usb2-phy.ko. Note: Some modules may be built-in
    C Some chips support different boards with varying numbers of USB ports. The USB port status is controlled via the board-level DTS. Verify that the DTS status is set to "okay"
    D Verify that VBUS is powered. Check whether the VBUS jumper for the corresponding port is connected. This can be measured with a multimeter or tested by connecting an LED-equipped WiFi dongle to check if the LED illuminates

    Issue 2. Upgrade via usbstar Fails in U-Boot

    Figure 2 usbstar Upgrade Failure Troubleshooting Flowchart
    Step Method
    A Verify that usbstar and USB 2.0 under usbstar are enabled in menuconfig
    B Verify that the USB 2.0 related status in DTS is set to "okay"
    C Check whether VBUS is powered using a multimeter
    D If the upgrade image name is not specified via usbstar -f, the default upgrade filename is SgsUpgrade.bin
    E Check whether the USB drive has multiple partitions and the file is located in a non-primary partition. The usbstar utility reads the first partition of the USB drive by default
    F USB drive upgrade currently supports FAT32 format only

    Issue 3. USB Drive Mount Failure

    Figure 3 USB Drive Mount Failure Troubleshooting Flowchart
    Step Method
    A First, verify whether the USB drive is recognized. If not, refer to the device recognition troubleshooting process
    B Execute cat /proc/filesystems to check whether the corresponding USB drive filesystem is loaded in the kernel
    C For example, execute mount /dev/sda1 /mnt -t vfat. The device may also be sdb1, sdc1, etc.

    Issue 4. USB 2.0 Device Not Recognized as High-Speed

    Figure 4 High-Speed Recognition Failure Troubleshooting Flowchart
    Step Method
    A When high-speed is recognized, the log "new high-speed USB device number 16 using ehci-hcd" will be displayed
    B Connect the device to a PC and use USBTreeView to verify that the Device Maximum Speed descriptor indicates "high-speed"
    C The cable quality may be defective. Test with a different cable
    D If the connection is not secure, poor contact may cause abnormal recognition