Geoff Levand df7c1ca229 usb: Fix PS3 EHCI suspend
The EHCI USB controller of the Cell Super Companion Chip used in the PS3
will stop the root hub after all root hub ports are suspended.  When in
this condition the ehci-hcd handshake routine will return -ETIMEDOUT and
the USB runtime suspend sequence will fail.  The STS_HLT bit will not be
set, so inspection of the frame index is used to test for the condition.

Add a new routine handshake_for_broken_root_hub() that is called after
an unsuccessful -ETIMEDOUT handshake.  On PS3 handshake_for_broken_root_hub()
will test for the condition, and if found will return success to allow the
USB suspend to complete.  For all other platforms
handshake_for_broken_root_hub() will return -ETIMEDOUT

Signed-off-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
2011-12-08 09:38:53 -08:00
..
2011-12-08 09:38:53 -08:00
2011-07-26 16:49:47 -07:00

To understand all the Linux-USB framework, you'll use these resources:

    * This source code.  This is necessarily an evolving work, and
      includes kerneldoc that should help you get a current overview.
      ("make pdfdocs", and then look at "usb.pdf" for host side and
      "gadget.pdf" for peripheral side.)  Also, Documentation/usb has
      more information.

    * The USB 2.0 specification (from www.usb.org), with supplements
      such as those for USB OTG and the various device classes.
      The USB specification has a good overview chapter, and USB
      peripherals conform to the widely known "Chapter 9".

    * Chip specifications for USB controllers.  Examples include
      host controllers (on PCs, servers, and more); peripheral
      controllers (in devices with Linux firmware, like printers or
      cell phones); and hard-wired peripherals like Ethernet adapters.

    * Specifications for other protocols implemented by USB peripheral
      functions.  Some are vendor-specific; others are vendor-neutral
      but just standardized outside of the www.usb.org team.

Here is a list of what each subdirectory here is, and what is contained in
them.

core/		- This is for the core USB host code, including the
		  usbfs files and the hub class driver ("khubd").

host/		- This is for USB host controller drivers.  This
		  includes UHCI, OHCI, EHCI, and others that might
		  be used with more specialized "embedded" systems.

gadget/		- This is for USB peripheral controller drivers and
		  the various gadget drivers which talk to them.


Individual USB driver directories.  A new driver should be added to the
first subdirectory in the list below that it fits into.

image/		- This is for still image drivers, like scanners or
		  digital cameras.
../input/	- This is for any driver that uses the input subsystem,
		  like keyboard, mice, touchscreens, tablets, etc.
../media/	- This is for multimedia drivers, like video cameras,
		  radios, and any other drivers that talk to the v4l
		  subsystem.
../net/		- This is for network drivers.
serial/		- This is for USB to serial drivers.
storage/	- This is for USB mass-storage drivers.
class/		- This is for all USB device drivers that do not fit
		  into any of the above categories, and work for a range
		  of USB Class specified devices. 
misc/		- This is for all USB device drivers that do not fit
		  into any of the above categories.