Question on uvcvideo driver's power management:
Q1: We found some USB material mentioned : Relationship between ACPI
Dx states and USB PM states (active/suspended) is orthogonal.
Suspend/resume might not effect device Dx state(e.g. D0/D1/D3). Is it
a correct statement for general usb device and uvcvideo usb device?
Q2: How to tell USB uvcvideo device’s ACPI Dx state. It seems lsusb
can’t tell us those info. (lspci works for PCI device’s Dx state)
Q3: How to tell USB uvcvideo device’s suspension state? will any query
via urb will cause resume of uvcvideo device?
Q4: should USB uvcvideo device driver response to do some
device-specific power action (e.g. device register writing) to put a
specific USB camera into low power state when responding to suspend
action? (I didn't find such device-specific power code inside uvcvideo
src code)
Q5: If Q4 is Yes, should device vendor respond for those device-specific code?

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