Sarah Sharp e7ecf069d4 xhci: Fix warning introduced by disabling runtime PM.
The 0day build server caught a new build warning that is triggered when
CONFIG_USB_DEFAULT_PERSIST is turned on:

tree:   git://git.kernel.org/pub/scm/linux/kernel/git/sarah/xhci.git for-usb-next
head:   0730d52a86919300a39a2be37f6c140997dfb82f
commit: c8476fb855434c733099079063990e5bfa7ecad6 [1/3] usb: xhci: Disable runtime PM suspend for quirky controllers
config: i386-randconfig-r6-0826 (attached as .config)

All warnings:

   drivers/usb/host/xhci.c: In function 'xhci_free_dev':
>> drivers/usb/host/xhci.c:3560:17: warning: unused variable 'dev' [-Wunused-variable]
     struct device *dev = hcd->self.controller;
                    ^
   drivers/usb/host/xhci.c: In function 'xhci_alloc_dev':
>> drivers/usb/host/xhci.c:3648:17: warning: unused variable 'dev' [-Wunused-variable]
     struct device *dev = hcd->self.controller;
                    ^

vim +/dev +3560 drivers/usb/host/xhci.c

  3554   * disabled.  Free any HC data structures associated with that device.
  3555   */
  3556  void xhci_free_dev(struct usb_hcd *hcd, struct usb_device *udev)
  3557  {
  3558          struct xhci_hcd *xhci = hcd_to_xhci(hcd);
  3559          struct xhci_virt_device *virt_dev;
> 3560          struct device *dev = hcd->self.controller;
  3561          unsigned long flags;
  3562          u32 state;
  3563          int i, ret;
  3564
  3565  #ifndef CONFIG_USB_DEFAULT_PERSIST
  3566          /*
  3567           * We called pm_runtime_get_noresume when the device was attached.
  3568           * Decrement the counter here to allow controller to runtime suspend
  3569           * if no devices remain.
  3570           */
  3571          if (xhci->quirks & XHCI_RESET_ON_RESUME)
  3572                  pm_runtime_put_noidle(dev);
  3573  #endif
  3574
...
  3641  /*
  3642   * Returns 0 if the xHC ran out of device slots, the Enable Slot command
  3643   * timed out, or allocating memory failed.  Returns 1 on success.
  3644   */
  3645  int xhci_alloc_dev(struct usb_hcd *hcd, struct usb_device *udev)
  3646  {
  3647          struct xhci_hcd *xhci = hcd_to_xhci(hcd);
> 3648          struct device *dev = hcd->self.controller;
  3649          unsigned long flags;
  3650          int timeleft;
  3651          int ret;

Fix this.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Shawn Nematbakhsh <shawnn@chromium.org>
2013-08-28 10:55:47 -07:00
..
2013-08-18 20:33:01 -07:00
2013-08-18 20:33:01 -07:00
2013-08-13 15:28:01 -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.