Commit Graph

56 Commits

Author SHA1 Message Date
Alan Stern 074f9dd55f USB: add flag for HCDs that can't receive wakeup requests (isp1760-hcd)
Currently the USB stack assumes that all host controller drivers are
capable of receiving wakeup requests from downstream devices.
However, this isn't true for the isp1760-hcd driver, which means that
it isn't safe to do a runtime suspend of any device attached to a
root-hub port if the device requires wakeup.

This patch adds a "cant_recv_wakeups" flag to the usb_hcd structure
and sets the flag in isp1760-hcd.  The core is modified to prevent a
direct child of the root hub from being put into runtime suspend with
wakeup enabled if the flag is set.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Nicolas Pitre <nico@linaro.org>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
2015-01-31 09:05:06 -08:00
Sebastian Andrzej Siewior 5efd2ea8c9 usb: core: buffer: smallest buffer should start at ARCH_DMA_MINALIGN
the following error pops up during "testusb -a -t 10"
| musb-hdrc musb-hdrc.1.auto: dma_pool_free buffer-128,	f134e000/be842000 (bad dma)
hcd_buffer_create() creates a few buffers, the smallest has 32 bytes of
size. ARCH_KMALLOC_MINALIGN is set to 64 bytes. This combo results in
hcd_buffer_alloc() returning memory which is 32 bytes aligned and it
might by identified by buffer_offset() as another buffer. This means the
buffer which is on a 32 byte boundary will not get freed, instead it
tries to free another buffer with the error message.

This patch fixes the issue by creating the smallest DMA buffer with the
size of ARCH_KMALLOC_MINALIGN (or 32 in case ARCH_KMALLOC_MINALIGN is
smaller). This might be 32, 64 or even 128 bytes. The next three pools
will have the size 128, 512 and 2048.
In case the smallest pool is 128 bytes then we have only three pools
instead of four (and zero the first entry in the array).
The last pool size is always 2048 bytes which is the assumed PAGE_SIZE /
2 of 4096. I doubt it makes sense to continue using PAGE_SIZE / 2 where
we would end up with 8KiB buffer in case we have 16KiB pages.
Instead I think it makes sense to have a common size(s) and extend them
if there is need to.
There is a BUILD_BUG_ON() now in case someone has a minalign of more than
128 bytes.

Cc: stable@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09 10:21:31 -08:00
Linus Torvalds e7cf773d43 USB patches for 3.19-rc1
Here's the big set of USB and PHY patches for 3.19-rc1.
 
 The normal churn in the USB gadget area is in here, as well as xhci and
 other individual USB driver updates.  The PHY tree is also in here, as
 there were dependancies on the USB tree.
 
 All of these have been in linux-next.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB updates from Greg KH:
 "Here's the big set of USB and PHY patches for 3.19-rc1.

  The normal churn in the USB gadget area is in here, as well as xhci
  and other individual USB driver updates.  The PHY tree is also in
  here, as there were dependancies on the USB tree.

  All of these have been in linux-next"

* tag 'usb-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (351 commits)
  arm: omap3: twl: remove usb phy init data
  usbip: fix error handling in stub_probe()
  usb: gadget: udc: missing curly braces
  USB: mos7720: delete some unneeded code
  wusb: replace memset by memzero_explicit
  usbip: remove unneeded structure
  usb: xhci: fix comment for PORT_DEV_REMOVE
  xhci: don't use the same variable for stopped and halted rings current TD
  xhci: clear extra bits from slot context when setting max exit latency
  xhci: cleanup finish_td function
  USB: adutux: NULL dereferences on disconnect
  usb: chipidea: fix platform_no_drv_owner.cocci warnings
  usb: chipidea: Fixed a few typos in comments
  Documentation: bindings: add doc for the USB2 ChipIdea USB driver
  usb: chipidea: add a usb2 driver for ci13xxx
  usb: chipidea: fix phy handling
  usb: chipidea: remove duplicate dev_set_drvdata for host_start
  usb: chipidea: parameter 'mode' isn't needed for hw_device_reset
  usb: chipidea: add controller reset API
  usb: chipidea: remove flag CI_HDRC_REQUIRE_TRANSCEIVER
  ...
2014-12-14 14:57:16 -08:00
Rafael J. Wysocki ceb6c9c862 USB / PM: Drop CONFIG_PM_RUNTIME from the USB core
After commit b2b49ccbdd (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is
selected) PM_RUNTIME is always set if PM is set, so quite a few
depend on CONFIG_PM (or even dropped in some cases).

Replace CONFIG_PM_RUNTIME with CONFIG_PM in the USB core code
and documentation.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-12-04 00:51:54 +01:00
Michael Grzeschik 11a7e59405 usb: ehci: add ehci_port_power interface
The current EHCI implementation is prepared to toggle the
PORT_POWER bit to enable or disable a USB-Port. In some
cases this port power can not be just toggled by the PORT_POWER
bit, and the gpio-regulator is needed to be toggled too.

This patch defines a port power control interface ehci_port_power for
ehci core use, it toggles PORT_POWER bit as well as calls platform
defined .port_power if it is defined.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Acked-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-03 15:34:00 -08:00
Sergei Shtylyov 0043325495 usb: hcd: add generic PHY support
Add the generic PHY support, analogous to the USB PHY support. Intended it to be
used with the PCI EHCI/OHCI drivers and the xHCI platform driver.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-29 11:54:02 -04:00
Antoine Tenart 3d46e73dfd usb: rename phy to usb_phy in HCD
The USB PHY member of the HCD structure is renamed to 'usb_phy' and
modifications are done in all drivers accessing it.
This is in preparation to adding the generic PHY support.

Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
[Sergei: added missing 'drivers/usb/misc/lvstest.c' file, resolved rejects,
updated changelog.]
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-29 11:52:59 -04:00
Peter Chen f2693b430b usb: hcd: add TPL support flag
The targeted hosts (non-PC hosts) need to have TPL (Targeted Peripheral List)
for USB OTG & EH certification and other vendor specific requirements.

The platform who needs TPL feature should set this flag at usb host
controller driver.

Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-23 21:28:41 -07:00
Oliver Neukum 14aec58932 storage: accept some UAS devices if streams are unavailable
On some older XHCIs streams are not supported and the UAS driver
will fail at probe time. For those devices storage should try
to bind to UAS devices.
This patch adds a flag for stream support to HCDs and evaluates
it.

[Note: Sarah fixed a bug where the USB 2.0 root hub, not USB 3.0 root
hub would get marked as being able to support streams.]

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
2014-03-04 15:41:09 -08:00
Dan Williams 48fc7dbd52 usb: xhci: change enumeration scheme to 'new scheme' by default
Change the default enumeration scheme for xhci attached non-SuperSpeed
devices from:

   Reset
   SetAddress [xhci address-device BSR = 0]
   GetDescriptor(8)
   GetDescriptor(18)

...to:

   Reset
   [xhci address-device BSR = 1]
   GetDescriptor(64)
   Reset
   SetAddress [xhci address-device BSR = 0]
   GetDescriptor(18)

...as some devices misbehave when encountering a SetAddress command
prior to GetDescriptor.  There are known legacy devices that require
this scheme, but testing has found at least one USB3 device that fails
enumeration when presented with this ordering.  For now, follow the ehci
case and enable 'new scheme' by default for non-SuperSpeed devices.

To support this enumeration scheme on xhci the AddressDevice operation
needs to be performed twice.  The first instance of the command enables
the HC's device and slot context info for the device, but omits sending
the device a SetAddress command (BSR == block set address request).
Then, after GetDescriptor completes, follow up with the full
AddressDevice+SetAddress operation.

As mentioned before, this ordering of events with USB3 devices causes an
extra state transition to be exposed to xhci.  Previously USB3 devices
would transition directly from 'enabled' to 'addressed' and never need
to underrun responses to 'get descriptor'. We do see the 64-byte
descriptor fetch the correct data, but the following 18-byte descriptor
read after the reset gets:

bLength            = 0
bDescriptorType    = 0
bcdUSB             = 0
bDeviceClass       = 0
bDeviceSubClass    = 0
bDeviceProtocol    = 0
bMaxPacketSize0    = 9

instead of:

bLength            = 12
bDescriptorType    = 1
bcdUSB             = 300
bDeviceClass       = 0
bDeviceSubClass    = 0
bDeviceProtocol    = 0
bMaxPacketSize0    = 9

which results in the discovery process looping until falling back to
'old scheme' enumeration.

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: David Moore <david.moore@gmail.com>
Suggested-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2013-12-10 13:54:37 -08:00
Valentine Barshak 103e127d1f usb: hcd: Remove USB phy if needed
This adds remove_phy flag to the HCD structure. If the flag is
set and if hcd->phy is valid, the phy is shutdown and released
whenever usb_add_hcd fails or usb_hcd_remove is called.
This can be used by the HCD drivers to auto-remove
the external USB phy when it is no longer needed.

Signed-off-by: Valentine Barshak <valentine.barshak@cogentembedded.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-08 18:00:51 -08:00
Alan Stern 7c4bb94298 USB: add a private-data pointer to struct usb_tt
For improved scheduling of transfers through a Transaction Translator,
ehci-hcd will need to store a bunch of information associated with the
FS/LS bus on the downstream side of the TT.  This patch adds a pointer
for such HCD-private data to the usb_tt structure.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 16:45:43 -07:00
Alan Stern 63fb3a2800 USB: NS_TO_US should round up
Host controller drivers use the NS_TO_US macro to convert transaction
times, which are computed in nanoseconds, to microseconds for
scheduling.  Periodic scheduling requires worst-case estimates, but
the macro does its conversion using round-to-nearest.  This patch
changes it to use round-up, giving a correct worst-case value.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-11 16:37:45 -07:00
Huang Rui 7868943db1 usb: core: implement AMD remote wakeup quirk
The following patch is required to resolve remote wake issues with
certain devices.

Issue description:
If the remote wake is issued from the device in a specific timing
condition while the system is entering sleep state then it may cause
system to auto wake on subsequent sleep cycle.

Root cause:
Host controller rebroadcasts the Resume signal > 100 µseconds after
receiving the original resume event from the device. For proper
function, some devices may require the rebroadcast of resume event
within the USB spec of 100µS.

Workaroud:
1. Filter the AMD platforms with Yangtze chipset, then judge of all the usb
devices are mouse or not. And get out the port id which attached a mouse
with Pixart controller.
2. Then reset the port which attached issue device during system resume
from S3.

[Q] Why the special devices are only mice? Would high speed devices
such as 3G modem or USB Bluetooth adapter trigger this issue?
- Current this sensitivity is only confined to devices that use Pixart
  controllers. This controller is designed for use with LS mouse
devices only. We have not observed any other devices failing. There
may be a small risk for other devices also but this patch (reset
device in resume phase) will cover the cases if required.

[Q] Shouldn’t the resume signal be sent within 100 us for every
device?
- The Host controller may not send the resume signal within 100us,
  this our host controller specification change. This is why we
require the patch to prevent side effects on certain known devices.

[Q] Why would clicking mouse INTENSELY to wake the system up trigger
this issue?
- This behavior is specific to the devices that use Pixart controller.
  It is timing dependent on when the resume event is triggered during
the sleep state.

[Q] Is it a host controller issue or mouse?
- It is the host controller behavior during resume that triggers the
  device incorrect behavior on the next resume.

This patch sets USB_QUIRK_RESET_RESUME flag for these Pixart-based mice
when they attached to platforms with AMD Yangtze chipset.

Signed-off-by: Huang Rui <ray.huang@amd.com>
Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-25 17:24:37 -07:00
Alan Stern c7ccde6eac USB: see if URB comes from a completion handler
Now that URBs can be completed inside tasklets, we need a way of
determining whether a completion handler for a given endpoint is
currently running.  Otherwise it's not possible to maintain the API
guarantee about keeping isochronous streams synchronous when an
underrun occurs.

This patch adds a field and a routine to check whether a completion
handler for a periodic endpoint is running.  At the moment no
analogous routine appears to be necessary for async endpoints, but one
can always be added.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-17 09:49:24 -07:00
Alan Stern 9d8924297c USB: fix build error when CONFIG_PM_SLEEP isn't enabled
This patch fixes a build error that occurs when CONFIG_PM is enabled
and CONFIG_PM_SLEEP isn't:

>> drivers/usb/host/ohci-pci.c:294:10: error: 'usb_hcd_pci_pm_ops' undeclared here (not in a function)
      .pm = &usb_hcd_pci_pm_ops

Since the usb_hcd_pci_pm_ops structure is defined and used when
CONFIG_PM is enabled, its declaration should not be protected by
CONFIG_PM_SLEEP.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-30 11:12:06 -07:00
Ming Lei 94dfd7edfd USB: HCD: support giveback of URB in tasklet context
This patch implements the mechanism of giveback of URB in
tasklet context, so that hardware interrupt handling time for
usb host controller can be saved much, and HCD interrupt handling
can be simplified.

Motivations:

1), on some arch(such as ARM), DMA mapping/unmapping is a bit
time-consuming, for example: when accessing usb mass storage
via EHCI on pandaboard, the common length of transfer buffer is 120KB,
the time consumed on DMA unmapping may reach hundreds of microseconds;
even on A15 based box, the time is still about scores of microseconds

2), on some arch, reading DMA coherent memoery is very time-consuming,
the most common example is usb video class driver[1]

3), driver's complete() callback may do much things which is driver
specific, so the time is consumed unnecessarily in hardware irq context.

4), running driver's complete() callback in hardware irq context causes
that host controller driver has to release its lock in interrupt handler,
so reacquiring the lock after return may busy wait a while and increase
interrupt handling time. More seriously, releasing the HCD lock makes
HCD becoming quite complicated to deal with introduced races.

So the patch proposes to run giveback of URB in tasklet context, then
time consumed in HCD irq handling doesn't depend on drivers' complete and
DMA mapping/unmapping any more, also we can simplify HCD since the HCD
lock isn't needed to be released during irq handling.

The patch should be reasonable and doable:

1), for drivers, they don't care if the complete() is called in hard irq
context or softirq context

2), the biggest change is the situation in which usb_submit_urb() is called
in complete() callback, so the introduced tasklet schedule delay might be a
con, but it shouldn't be a big deal:

	- control/bulk asynchronous transfer isn't sensitive to schedule
	  delay

	- the patch schedules giveback of periodic URBs using
	  tasklet_hi_schedule, so the introduced delay should be very
	  small

	- for ISOC transfer, generally, drivers submit several URBs
	  concurrently to avoid interrupt delay, so it is OK with the
	  little schedule delay.

	- for interrupt transfer, generally, drivers only submit one URB
	  at the same time, but interrupt transfer is often used in event
	  report, polling, ... situations, and a little delay should be OK.

Considered that HCDs may optimize on submitting URB in complete(), the
patch may cause the optimization not working, so introduces one flag to mark
if the HCD supports to run giveback URB in tasklet context. When all HCDs
are ready, the flag can be removed.

[1], http://marc.info/?t=136438111600010&r=1&w=2

Cc: Oliver Neukum <oliver@neukum.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-12 11:43:48 -07:00
Thomas Pugliese 1a81f8814c Allow the USB HCD to create Wireless USB root hubs
This patch adds Wireless USB root hub support to the USB HCD.  It allows
the HWA to create its root hub which previously failed because the HCD
treated wireless root hubs the same as USB2 high speed hubs.  The creation
of the root hub would fail in that case due to lack of TTs which wireless
root hubs do not support.

Signed-off-by: Thomas Pugliese <thomas.pugliese@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-03 10:52:40 -07:00
Alan Stern 84ebc10294 USB: remove CONFIG_USB_SUSPEND option
This patch (as1675) removes the CONFIG_USB_SUSPEND option, essentially
replacing it everywhere with CONFIG_PM_RUNTIME (except for one place
in hub.c, where it is replaced with CONFIG_PM because the code needs
to be used in both runtime and system PM).  The net result is code
shrinkage and simplification.

There's very little point in keeping CONFIG_USB_SUSPEND because almost
everybody enables it.  The few that don't will find that the usbcore
module has gotten somewhat bigger and they will have to take active
measures if they want to prevent hubs from being runtime suspended.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-28 11:10:22 -07:00
Lan Tianyu 3f5eb14135 usb: add find_raw_port_number callback to struct hc_driver()
xhci driver divides the root hub into two logical hubs which work
respectively for usb 2.0 and usb 3.0 devices. They are independent
devices in the usb core. But in the ACPI table, it's one device node
and all usb2.0 and usb3.0 ports are under it. Binding usb port with
its acpi node needs the raw port number which is reflected in the xhci
extended capabilities table. This patch is to add find_raw_port_number
callback to struct hc_driver(), fill it with xhci_find_raw_port_number()
which will return raw port number and add a wrap usb_hcd_find_raw_port_number().

Otherwise, refactor xhci_find_real_port_number(). Using
xhci_find_raw_port_number() to get real index in the HW port status
registers instead of scanning through the xHCI roothub port array.
This can help to speed up.

All addresses in xhci->usb2_ports and xhci->usb3_ports array are
kown good ports and don't include following bad ports in the extended
capabilities talbe.
     (1) root port that doesn't have an entry
     (2) root port with unknown speed
     (3) root port that is listed twice and with different speeds.

So xhci_find_raw_port_number() will only return port num of good ones
and never touch bad ports above.

Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2013-03-25 10:39:17 -07:00
Alan Stern da0aa7169b USB: add usb_hcd_{start,end}_port_resume
This patch (as1649) adds a mechanism for host controller drivers to
inform usbcore when they have begun or ended resume signalling on a
particular root-hub port.  The core will then make sure that the root
hub does not get runtime-suspended while the port resume is going on.

Since commit 596d789a21 (USB: set hub's
default autosuspend delay as 0), the system tries to suspend hubs
whenever they aren't in use.  While a root-hub port is being resumed,
the root hub does not appear to be in use.  Attempted runtime suspends
fail because of the ongoing port resume, but the PM core just keeps on
trying over and over again.  We want to prevent this wasteful effort.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-25 15:06:01 -08:00
Kishon Vijay Abraham I 26f944b271 usb: hcd: use *resource_size_t* for specifying resource data
Changed the type of rsrc_start and rsrc_len from u64 to resource_size_t
so that it behaves well with resource API's like *resource_size()* on both
32bit and 64bit devices.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-16 14:04:14 -07:00
Greg Kroah-Hartman e17f8af316 Merge branch 'usb-linus' into usb-next
This is to pick up the changes to the option driver, which are needed
for follow-on patches from Johan.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-13 15:22:54 -07:00
Alan Stern c2fb8a3fa2 USB: add NO_D3_DURING_SLEEP flag and revert 151b612847
This patch (as1558) fixes a problem affecting several ASUS computers:
The machine crashes or corrupts memory when going into suspend if the
ehci-hcd driver is bound to any controllers.  Users have been forced
to unbind or unload ehci-hcd before putting their systems to sleep.

After extensive testing, it was determined that the machines don't
like going into suspend when any EHCI controllers are in the PCI D3
power state.  Presumably this is a firmware bug, but there's nothing
we can do about it except to avoid putting the controllers in D3
during system sleep.

The patch adds a new flag to indicate whether the problem is present,
and avoids changing the controller's power state if the flag is set.
Runtime suspend is unaffected; this matters only for system suspend.
However as a side effect, the controller will not respond to remote
wakeup requests while the system is asleep.  Hence USB wakeup is not
functional -- but of course, this is already true in the current state
of affairs.

A similar patch has already been applied as commit
151b612847 (USB: EHCI: fix crash during
suspend on ASUS computers).  The patch supersedes that one and reverts
it.  There are two differences:

	The old patch added the flag at the USB level; this patch
	adds it at the PCI level.

	The old patch applied to all chipsets with the same vendor,
	subsystem vendor, and product IDs; this patch makes an
	exception for a known-good system (based on DMI information).

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Dâniel Fraga <fragabr@gmail.com>
Tested-by: Andrey Rahmatullin <wrar@wrar.name>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-13 13:11:39 -07:00
Richard Zhao c2e935a7db USB: move transceiver from ehci_hcd and ohci_hcd to hcd and rename it as phy
- to decrease redundant since both ehci_hcd and ohci_hcd have the same variable
 - it helps access phy in usb core code
 - phy is more meaningful than transceiver

Signed-off-by: Richard Zhao <richard.zhao@freescale.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-13 12:38:36 -07:00
Sarah Sharp 1ea7e0e8e3 USB: Add support to enable/disable USB3 link states.
There are various functions within the USB core that will need to
disable USB 3.0 link power states.  For example, when a USB device
driver is being bound to an interface, we need to disable USB 3.0 LPM
until we know if the driver will allow hub-initiated LPM transitions.
Another example is when the USB core is switching alternate interface
settings.  The USB 3.0 timeout values are dependent on what endpoints
are enabled, so we want to ensure that LPM is disabled until the new alt
setting is fully installed.

Multiple functions need to disable LPM, and those functions can even be
nested.  For example, usb_bind_interface() could disable LPM, and then
call into the driver probe function, which may attempt to switch to a
different alt setting.  Therefore, we need to keep a count of the number
of functions that require LPM to be disabled at any point in time.

Introduce two new USB core API calls, usb_disable_lpm() and
usb_enable_lpm().  These functions increment and decrement a new
variable in the usb_device, lpm_disable_count.  If usb_disable_lpm()
fails, it will call usb_enable_lpm() in order to balance the
lpm_disable_count.

These two new functions must be called with the bandwidth_mutex locked.
If the bandwidth_mutex is not already held by the caller, it should
instead call usb_unlocked_disable_lpm() and usb_enable_lpm(), which take
the bandwidth_mutex before calling usb_disable_lpm() and
usb_enable_lpm(), respectively.

Introduce a new variable (timeout) in the usb3_lpm_params structure to
keep track of the currently enabled U1/U2 timeout values.  When
usb_disable_lpm() is called, and the USB device has the U1 or U2
timeouts set to a non-zero value (meaning either device-initiated or
hub-initiated LPM is enabled), attempt to disable LPM, regardless of the
state of the lpm_disable_count.  We want to ensure that all callers can
be guaranteed that LPM is disabled if usb_disable_lpm() returns zero.

Otherwise the following scenario could occur:

1. Driver A is being bound to interface 1.  usb_probe_interface()
disables LPM.  Driver A doesn't care if hub-initiated LPM is enabled, so
even though usb_disable_lpm() fails, the probe of the driver continues,
and the bandwidth mutex is dropped.

2. Meanwhile, Driver B is being bound to interface 2.
usb_probe_interface() grabs the bandwidth mutex and calls
usb_disable_lpm().  That call should attempt to disable LPM, even
though the lpm_disable_count is set to 1 by Driver A.

For usb_enable_lpm(), we attempt to enable LPM only when the
lpm_disable_count is zero.  If some step in enabling LPM fails, it will
only have a minimal impact on power consumption, and all USB device
drivers should still work properly.  Therefore don't bother to return
any error codes.

Don't enable device-initiated LPM if the device is unconfigured.  The
USB device will only accept the U1/U2_ENABLE control transfers in the
configured state.  Do enable hub-initiated LPM in that case, since
devices are allowed to accept the LGO_Ux link commands in any state.

Don't enable or disable LPM if the device is marked as not being LPM
capable.  This can happen if:
 - the USB device doesn't have a SS BOS descriptor,
 - the device's parent hub has a zeroed bHeaderDecodeLatency value, or
 - the xHCI host doesn't support LPM.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Andiry Xu <andiry.xu@amd.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-05-18 15:41:58 -07:00
Greg Kroah-Hartman 61906313bd Merge 3.4-rc6 into usb-next
This resolves the conflict with:
	drivers/usb/host/ehci-tegra.c

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-07 09:03:39 -07:00
Greg Kroah-Hartman fb28d58b72 USB: remove CONFIG_USB_DEVICEFS
This option has been deprecated for many years now, and no userspace
tools use it anymore, so it should be safe to finally remove it.

Reported-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-29 22:20:03 -04:00
Alan Stern 151b612847 USB: EHCI: fix crash during suspend on ASUS computers
This patch (as1545) fixes a problem affecting several ASUS computers:
The machine crashes or corrupts memory when going into suspend if the
ehci-hcd driver is bound to any controllers.  Users have been forced
to unbind or unload ehci-hcd before putting their systems to sleep.

After extensive testing, it was determined that the machines don't
like going into suspend when any EHCI controllers are in the PCI D3
power state.  Presumably this is a firmware bug, but there's nothing
we can do about it except to avoid putting the controllers in D3
during system sleep.

The patch adds a new flag to indicate whether the problem is present,
and avoids changing the controller's power state if the flag is set.
Runtime suspend is unaffected; this matters only for system suspend.
However as a side effect, the controller will not respond to remote
wakeup requests while the system is asleep.  Hence USB wakeup is not
functional -- but of course, this is already true in the current state
of affairs.

This fixes Bugzilla #42728.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Tested-by: Andrey Rahmatullin <wrar@wrar.name>
Tested-by: Oleksij Rempel (fishor) <bug-track@fisher-privat.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-24 13:55:43 -07:00
Felipe Balbi cd70469d08 usb: core: hcd: make hcd->irq unsigned
There's really no point in having hcd->irq as a
signed integer when we consider the fact that
IRQ 0 means NO_IRQ. In order to avoid confusion,
make hcd->irq unsigned and fix users who were
passing -1 as the IRQ number to usb_add_hcd.

Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-01 09:31:22 -08:00
Sarah Sharp 4ee823b83b USB/xHCI: Support device-initiated USB 3.0 resume.
USB 3.0 hubs don't have a port suspend change bit (that bit is now
reserved).  Instead, when a host-initiated resume finishes, the hub sets
the port link state change bit.

When a USB 3.0 device initiates remote wakeup, the parent hubs with
their upstream links in U3 will pass the LFPS up the chain.  The first
hub that has an upstream link in U0 (which may be the roothub) will
reflect that LFPS back down the path to the device.

However, the parent hubs in the resumed path will not set their link
state change bit.  Instead, the device that initiated the resume has to
send an asynchronous "Function Wake" Device Notification up to the host
controller.  Therefore, we need a way to notify the USB core of a device
resume without going through the normal hub URB completion method.

First, make the xHCI roothub act like an external USB 3.0 hub and not
pass up the port link state change bit when a device-initiated resume
finishes.  Introduce a new xHCI bit field, port_remote_wakeup, so that
we can tell the difference between a port coming out of the U3Exit state
(host-initiated resume) and the RExit state (ending state of
device-initiated resume).

Since the USB core can't tell whether a port on a hub has resumed by
looking at the Hub Status buffer, we need to introduce a bitfield,
wakeup_bits, that indicates which ports have resumed.  When the xHCI
driver notices a port finishing a device-initiated resume, we call into
a new USB core function, usb_wakeup_notification(), that will set
the right bit in wakeup_bits, and kick khubd for that hub.

We also call usb_wakeup_notification() when the Function Wake Device
Notification is received by the xHCI driver.  This covers the case where
the link between the roothub and the first-tier hub is in U0, and the
hub reflects the resume signaling back to the device without giving any
indication it has done so until the device sends the Function Wake
notification.

Change the code in khubd that handles the remote wakeup to look at the
state the USB core thinks the device is in, and handle the remote wakeup
if the port's wakeup bit is set.

This patch only takes care of the case where the device is attached
directly to the roothub, or the USB 3.0 hub that is attached to the root
hub is the device sending the Function Wake Device Notification (e.g.
because a new USB device was attached).  The other cases will be covered
in a second patch.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-02-14 12:12:26 -08:00
Alan Stern 968b822c00 USB: Remove the SAW_IRQ hcd flag
The HCD_FLAG_SAW_IRQ flag was introduced in order to catch IRQ routing
errors: If an URB was unlinked and the host controller hadn't gotten
any IRQs, it seemed likely that the IRQs were directed to the wrong
vector.

This warning hasn't come up in many years, as far as I know; interrupt
routing now seems to be well under control.  Therefore there's no
reason to keep the flag around any more.  This patch (as1495) finally
removes it.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-14 16:46:06 -08:00
Harro Haan 276532ba96 USB: fix ehci alignment error
The Kirkwood gave an unaligned memory access error on
line 742 of drivers/usb/host/echi-hcd.c:
"ehci->last_periodic_enable = ktime_get_real();"

Signed-off-by: Harro Haan <hrhaan@gmail.com>
Cc: stable <stable@kernel.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-10 16:43:53 -07:00
Andiry Xu 65580b4321 xHCI: set USB2 hardware LPM
If the device pass the USB2 software LPM and the host supports hardware
LPM, enable hardware LPM for the device to let the host decide when to
put the link into lower power state.

If hardware LPM is enabled for a port and driver wants to put it into
suspend, it must first disable hardware LPM, resume the port into U0,
and then suspend the port.

Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-09-26 15:51:10 -07:00
Sarah Sharp c563543784 usb: Make core allocate resources per PCI-device.
Introduce the notion of a PCI device that may be associated with more than
one USB host controller driver (struct usb_hcd).  This patch is the start
of the work to separate the xHCI host controller into two roothubs: a USB
3.0 roothub with SuperSpeed-only ports, and a USB 2.0 roothub with
HS/FS/LS ports.

One usb_hcd structure is designated to be the "primary HCD", and a pointer
is added to the usb_hcd structure to keep track of that.  A new function
call, usb_hcd_is_primary_hcd() is added to check whether the USB hcd is
marked as the primary HCD (or if it is not part of a roothub pair).  To
allow the USB core and xHCI driver to access either roothub in a pair, a
"shared_hcd" pointer is added to the usb_hcd structure.

Add a new function, usb_create_shared_hcd(), that does roothub allocation
for paired roothubs.  It will act just like usb_create_hcd() did if the
primary_hcd pointer argument is NULL.  If it is passed a non-NULL
primary_hcd pointer, it sets usb_hcd->shared_hcd and usb_hcd->primary_hcd
fields.  It will also skip the bandwidth_mutex allocation, and set the
secondary hcd's bandwidth_mutex pointer to the primary HCD's mutex.

IRQs are only allocated once for the primary roothub.

Introduce a new usb_hcd driver flag that indicates the host controller
driver wants to create two roothubs.  If the HCD_SHARED flag is set, then
the USB core PCI probe methods will allocate a second roothub, and make
sure that second roothub gets freed during rmmod and in initialization
error paths.

When usb_hc_died() is called with the primary HCD, make sure that any
roothubs that share that host controller are also marked as being dead.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2011-03-13 18:23:06 -07:00
Sarah Sharp 83de4b2b90 usb: Store bus type in usb_hcd, not in driver flags.
The xHCI driver essentially has both a USB 2.0 and a USB 3.0 roothub.  So
setting the HCD_USB3 bits in the hcd->driver->flags is a bit misleading.
Add a new field to usb_hcd, bcdUSB.  Store the result of
hcd->driver->flags & HCD_MASK in it.  Later, when we have the xHCI driver
register the two roothubs, we'll set the usb_hcd->bcdUSB field to HCD_USB2
for the USB 2.0 roothub, and HCD_USB3 for the USB 3.0 roothub.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2011-03-13 18:07:15 -07:00
Sarah Sharp d673bfcbff usb: Change usb_hcd->bandwidth_mutex to a pointer.
Change the bandwith_mutex in struct usb_hcd to a pointer.  This will allow
the pointer to be shared across usb_hcds for the upcoming work to split
the xHCI driver roothub into a USB 2.0/1.1 and a USB 3.0 bus.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2011-03-13 18:07:14 -07:00
Sarah Sharp da13051cc7 USB: Remove bitmap #define from hcd.h
Using a #define to redefine a common variable name is a bad thing,
especially when the #define is in a header.  include/linux/usb/hcd.h
redefined bitmap to DeviceRemovable to avoid typing a long field in the
hub descriptor.  This has unintended side effects for files like
drivers/usb/core/devio.c that include that file, since another header
included after hcd.h has different variables named bitmap.

Remove the bitmap #define and replace instances of it in the host
controller code.  Cleanup the spaces around function calls and square
brackets while we're at it.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Cc: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Cc: Tony Olech <tony.olech@elandigitalsystems.com>
Cc: "Robert P. J. Day" <rpjday@crashcourse.ca>
Cc: Max Vozeler <mvz@vozeler.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: Rodolfo Giometti <giometti@linux.it>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Anton Vorontsov <avorontsov@mvista.com>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Lothar Wassmann <LW@KARO-electronics.de>
Cc: Olav Kongas <ok@artecdesign.ee>
Cc: Martin Fuzzey <mfuzzey@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: David Brownell <dbrownell@users.sourceforge.net>
2011-03-13 18:07:07 -07:00
Alan Stern 9b37596a2e USB: move usbcore away from hcd->state
The hcd->state variable is a disaster.  It's not clearly owned by
either usbcore or the host controller drivers, and they both change it
from time to time, potentially stepping on each other's toes.  It's
not protected by any locks.  And there's no mechanism to prevent it
from going through an invalid transition.

This patch (as1451) takes a first step toward fixing these problems.
As it turns out, usbcore uses hcd->state for essentially only two
things: checking whether the controller's root hub is running and
checking whether the controller has died.  Therefore the patch adds
two new atomic bitflags to the hcd structure, to store these pieces of
information.  The new flags are used only by usbcore, and a private
spinlock prevents invalid combinations (a dead controller's root hub
cannot be running).

The patch does not change the places where usbcore sets hcd->state,
since HCDs may depend on them.  Furthermore, there is one place in
usb_hcd_irq() where usbcore still must use hcd->state: An HCD's
interrupt handler can implicitly indicate that the controller died by
setting hcd->state to HC_STATE_HALT.  Nevertheless, the new code is a
big improvement over the current code.

The patch makes one other change.  The hcd_bus_suspend() and
hcd_bus_resume() routines now check first whether the host controller
has died; if it has then they return immediately without calling the
HCD's bus_suspend or bus_resume methods.

This fixes the major problem reported in Bugzilla #29902: The system
fails to suspend after a host controller dies during system resume.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Alex Terekhov <a.terekhov@gmail.com>
CC: <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-07 12:14:06 -08:00
Greg Kroah-Hartman 66b0835e2b Merge 2.6.38-rc5 into usb-next
This is needed to resolve some merge conflicts that were found
in the USB host controller patches, and reported by Stephen Rothwell.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-17 09:56:55 -08:00
Robert Morell 2694a48d90 USB: HCD: Add driver hooks for (un)?map_urb_for_dma
Provide optional hooks for the host controller driver to override the
default DMA mapping and unmapping routines.  In general, these shouldn't
be necessary unless the host controller has special DMA requirements,
such as alignment contraints.  If these are not specified, the
general usb_hcd_(un)?map_urb_for_dma functions will be used instead.
Also, pass the status to unmap_urb_for_dma so it can know whether the
DMA buffer has been overwritten.

Finally, add a flag to be used by these implementations if they
allocated a temporary buffer so it can be freed properly when unmapping.

Signed-off-by: Robert Morell <rmorell@nvidia.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-04 11:48:55 -08:00
Robert Morell c8cf203a1d USB: HCD: Add usb_hcd prefix to exported functions
The convention is to prefix symbols exported from the USB HCD core with
"usb_hcd".  This change makes unmap_urb_setup_for_dma() and
unmap_urb_for_dma() consistent with that.

Signed-off-by: Robert Morell <rmorell@nvidia.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-04 11:48:18 -08:00
Andiry Xu 0029227f1b xHCI: synchronize irq in xhci_suspend()
Synchronize the interrupts instead of free them in xhci_suspend(). This will
prevent a double free when the host is suspended and then the card removed.

Set the flag hcd->msix_enabled when using MSI-X, and check the flag in
suspend_common(). MSI-X synchronization will be handled by xhci_suspend(),
and MSI/INTx will be synchronized in suspend_common().

This patch should be queued for the 2.6.37 stable tree.

Reported-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@kernel.org
2011-01-14 15:28:52 -08:00
Tatyana Brokhman 0eadcc0920 usb: USB3.0 ch11 definitions
Adding hub SuperSpeed usb definitions as defined by ch10 of the USB3.0
spec.

Signed-off-by: Tatyana Brokhman <tlinder@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-11 06:19:35 -08:00
Martin Fuzzey 1dae423dd9 USB: introduce unmap_urb_setup_for_dma()
Split unmap_urb_for_dma() to allow just the setup buffer
to be unmapped. This allows HCDs to use PIO for the setup
buffer if it is not suitable for DMA.

Signed-off-by: Martin Fuzzey <mfuzzey@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-10-22 10:22:03 -07:00
Maulik Mankad 496dda704b usb: musb: host: unmap the buffer for PIO data transfers
The USB stack maps the buffer for DMA if the controller supports DMA.
MUSB controller can perform DMA as well as PIO transfers.
The buffer needs to be unmapped before CPU can perform
PIO data transfers.

Export unmap_urb_for_dma() so that drivers can perform
the DMA unmapping in a sane way.

Signed-off-by: Maulik Mankad <x0082077@ti.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-10-22 10:21:53 -07:00
Alan Stern ff2f078743 USB: fix race between root-hub wakeup & controller suspend
This patch (as1395) adds code to hcd_pci_suspend() for handling wakeup
races.  This is another general race pattern, similar to the "open
vs. unregister" race we're all familiar with.  Here, the race is
between suspending a device and receiving a wakeup request from one of
the device's suspended children.

In particular, if a root-hub wakeup is requested at about the same
time as the corresponding USB controller is suspended, and if the
controller is enabled for wakeup, then the controller should either
fail to suspend or else wake right back up again.

During system sleep this won't happen very much, especially since host
controllers generally aren't enabled for wakeup during sleep.  However
it is definitely an issue for runtime PM.  Something like this will be
needed to prevent the controller from autosuspending while waiting for
a root-hub resume to take place.  (That is, in fact, the common case,
for which there is an extra test.)

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10 14:35:38 -07:00
Alan Stern 4147200d25 USB: add do_wakeup parameter for PCI HCD suspend
This patch (as1385) adds a "do_wakeup" parameter to the pci_suspend
method used by PCI-based host controller drivers.  ehci-hcd in
particular needs to know whether or not to enable wakeup when
suspending a controller.  Although that information is currently
available through device_may_wakeup(), when support is added for
runtime suspend this will no longer be true.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10 14:35:37 -07:00
Alan Stern 541c7d432f USB: convert usb_hcd bitfields into atomic flags
This patch (as1393) converts several of the single-bit fields in
struct usb_hcd to atomic flags.  This is for safety's sake; not all
CPUs can update bitfield values atomically, and these flags are used
in multiple contexts.

The flag fields that are set only during registration or removal can
remain as they are, since non-atomic accesses at those times will not
cause any problems.

(Strictly speaking, the authorized_default flag should become atomic
as well.  I didn't bother with it because it gets changed only via
sysfs.  It can be done later, if anyone wants.)

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10 14:35:37 -07:00
Alek Du 48f2497014 USB: EHCI: EHCI 1.1 addendum: Basic LPM feature support
With this patch, the LPM capable EHCI host controller can put device
into L1 sleep state which is a mode that can enter/exit quickly, and
reduce power consumption.

Signed-off-by: Jacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: Alek Du <alek.du@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-10 14:35:35 -07:00