Files
linux/drivers/usb
Takashi Iwai 638298dc66 xhci: Fix spurious wakeups after S5 on Haswell
Haswell LynxPoint and LynxPoint-LP with the recent Intel BIOS show
mysterious wakeups after shutdown occasionally.  After discussing with
BIOS engineers, they explained that the new BIOS expects that the
wakeup sources are cleared and set to D3 for all wakeup devices when
the system is going to sleep or power off, but the current xhci driver
doesn't do this properly (partly intentionally).

This patch introduces a new quirk, XHCI_SPURIOUS_WAKEUP, for
fixing the spurious wakeups at S5 by calling xhci_reset() in the xhci
shutdown ops as done in xhci_stop(), and setting the device to PCI D3
at shutdown and remove ops.

The PCI D3 call is based on the initial fix patch by Oliver Neukum.

[Note: Sarah changed the quirk name from XHCI_HSW_SPURIOUS_WAKEUP to
XHCI_SPURIOUS_WAKEUP, since none of the other quirks have system names
in them.  Sarah also fixed a collision with a quirk submitted around the
same time, by changing the xhci->quirks bit from 17 to 18.]

This patch should be backported to kernels as old as 3.0, that
contain the commit 1c12443ab8 "xhci: Add
Lynx Point to list of Intel switchable hosts."

Cc: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
2013-10-09 16:27:20 -07:00
..
2013-08-18 20:33:01 -07:00
2013-08-18 20:33:01 -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.