Switching between USB modes

[helg]

I have some empiric evidence of an unintended switch between the USB mass storage and UVC webcam on mini5,
which i wanted to share, because streaming video over USB can be an interesting option.
Here is the normal 'USB mass storage' mode, which allows you to access the eMMC user partition:

[  750.185054] usb 1-3: new high-speed USB device number 11 using xhci_hcd
[  750.334180] usb 1-3: New USB device found, idVendor=0525, idProduct=a4a5, bcdDevice= 4.09
[  750.334188] usb 1-3: New USB device strings: Mfr=3, Product=4, SerialNumber=0
[  750.334193] usb 1-3: Product: Mass Storage Gadget
[  750.334197] usb 1-3: Manufacturer: Linux 4.9.37 with dwc3-gadget
[  750.335921] usb-storage 1-3:1.0: USB Mass Storage device detected
[  750.336241] usb-storage 1-3:1.0: Quirks match for vid 0525 pid a4a5: 10000
[  750.336310] scsi host3: usb-storage 1-3:1.0
[  751.357477] scsi 3:0:0:0: Direct-Access     Linux    File-Stor Gadget 0409 PQ: 0 ANSI: 2
[  751.358231] sd 3:0:0:0: Attached scsi generic sg1 type 0
[  751.358268] sd 3:0:0:0: Power-on or device reset occurred
[  751.358597] sd 3:0:0:0: [sdb] 120397824 512-byte logical blocks: (61.6 GB/57.4 GiB)
[  751.358751] sd 3:0:0:0: [sdb] Write Protect is off
[  751.358758] sd 3:0:0:0: [sdb] Mode Sense: 0f 00 00 00
[  751.358907] sd 3:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[  751.360254]  sdb:
[  751.363011] sd 3:0:0:0: [sdb] Attached SCSI removable disk
[  753.000484] usb 1-3: USB disconnect, device number 11
[  753.007034] sd 3:0:0:0: [sdb] Synchronizing SCSI cache
[  753.007052] sd 3:0:0:0: [sdb] Synchronize Cache(10) failed: Result: hostbyte=DID_NO_CONNECT driverbyte=DRIVER_OK

and after that it switched to UVC webcam:

[  753.412803] usb 1-3: new high-speed USB device number 12 using xhci_hcd
[  753.561759] usb 1-3: New USB device found, idVendor=1d6b, idProduct=0102, bcdDevice= 4.09
[  753.561766] usb 1-3: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[  753.561770] usb 1-3: Product: Webcam gadget
[  753.561773] usb 1-3: Manufacturer: Linux Foundation
[  753.563178] uvcvideo: Unknown video format 3132564e-0000-0010-8000-00aa00389b71
[  753.563199] uvcvideo: Found UVC 1.10 device Webcam gadget (1d6b:0102)
[  753.566802] input: Webcam gadget: UVC Camera as /devices/pci0000:00/0000:00:14.0/usb1/1-3/1-3:1.0/input/input22

 

[vjiethoang]

mini 5 flash fimw hard drive hangs, red led indicator and does not recognize hard drive on pc when plugged in usb now how can i make the camera work please help me