USB APM suspend

[Alan Stern]

Here's a piece from my system log, when I did "apm --suspend".  The 
usb_device_suspend/resume messages are things I added for debugging.

Sep 19 17:02:35 ida kernel: uhci-hcd 0000:00:07.2: suspend to state 3
Sep 19 17:02:35 ida kernel: drivers/usb/host/uhci-hcd.c: 6400: suspend_hc
Sep 19 17:02:35 ida kernel: usb_device_suspend: 1-1:0
Sep 19 17:02:35 ida kernel: usb_device_suspend: 1-1
Sep 19 17:02:35 ida kernel: usb_device_suspend: 1-0:0
Sep 19 17:02:35 ida kernel: usb_device_suspend: usb1
Sep 19 17:02:45 ida kernel: uhci-hcd 0000:00:07.2: suspend D4 --> D3
Sep 19 17:02:45 ida kernel: drivers/usb/host/uhci-hcd.c: 6400: wakeup_hc
Sep 19 17:02:45 ida kernel: usb_device_resume: usb1
Sep 19 17:02:45 ida kernel: usb_device_resume: 1-0:0
Sep 19 17:02:45 ida kernel: usb_device_resume: 1-1
Sep 19 17:02:45 ida kernel: usb_device_resume: 1-1:0
Sep 19 17:02:45 ida kernel: uhci-hcd 0000:00:07.2: can't resume, not suspended!

This has several odd things.  Note that both the first two "0000:00:07.2"  
messages were created by hcd-pci.c, in its usb_hcd_pci_suspend() routine.  

Why was this routine called twice?  (Don't be fooled by the timestamps; I 
think the "suspend D4 --> D3" message was created during the suspend but 
not read by syslogd until after the resume.)

Why doesn't usb_hcd_pci_resume() log a similar message when it is called?
A simple oversight?

Why was the host controller suspended _before_ its child USB devices?  

And why was it woken up twice?

Alan Stern


P.S.: Greg, what on Earth does "GREG: gregindex = 0" mean?

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