Commit Graph

253 Commits

Author SHA1 Message Date
Ming Lei 428aac8a81 USB: EHCI: support running URB giveback in tasklet context
All 4 transfer types can work well on EHCI HCD after switching to run
URB giveback in tasklet context, so mark all HCD drivers to support
it.

Also we don't need to release ehci->lock during URB giveback any more.

>From below test results on 3 machines(2 ARM and one x86), time
consumed by EHCI interrupt handler droped much without performance
loss.

1 test description
1.1 mass storage performance test:
- run below command 10 times and compute the average performance

    dd if=/dev/sdN iflag=direct of=/dev/null bs=200M count=1

- two usb mass storage device:
A: sandisk extreme USB 3.0 16G(used in test case 1 & case 2)
B: kingston DataTraveler G2 4GB(only used in test case 2)

1.2 uvc function test:
- run one simple capture program in the below link

   http://kernel.ubuntu.com/~ming/up/capture.c

- capture format 640*480 and results in High Bandwidth mode on the
uvc device: Z-Star 0x0ac8/0x3450

- on T410(x86) laptop, also use guvcview to watch video capture/playback

1.3 about test2 and test4
- both two devices involved are tested concurrently by above test items

1.4 how to compute irq time(the time consumed by ehci_irq)
- use trace points of irq:irq_handler_entry and irq:irq_handler_exit

1.5 kernel
3.10.0-rc3-next-20130528

1.6 test machines
Pandaboard A1: ARM CortexA9 dural core
Arndale board: ARM CortexA15 dural core
T410: i5 CPU 2.67GHz quad core

2 test result
2.1 test case1: single mass storage device performance test
--------------------------------------------------------------------
		upstream 		| patched
		perf(MB/s)+irq time(us)	| perf(MB/s)+irq time(us)
--------------------------------------------------------------------
Pandaboard A1:  25.280(avg:145,max:772)	| 25.540(avg:14, max:75)
Arndale board:  29.700(avg:33, max:129)	| 29.700(avg:10,  max:50)
T410: 		34.430(avg:17, max:154*)| 34.660(avg:12, max:155)
---------------------------------------------------------------------

2.2 test case2: two mass storage devices' performance test
--------------------------------------------------------------------
		upstream 			| patched
		perf(MB/s)+irq time(us)		| perf(MB/s)+irq time(us)
--------------------------------------------------------------------
Pandaboard A1:  15.840/15.580(avg:158,max:1216)	| 16.500/16.160(avg:15,max:139)
Arndale board:  17.370/16.220(avg:33 max:234)	| 17.480/16.200(avg:11, max:91)
T410: 		21.180/19.820(avg:18 max:160)	| 21.220/19.880(avg:11, max:149)
---------------------------------------------------------------------

2.3 test case3: one uvc streaming test
- uvc device works well(on x86, luvcview can be used too and has
same result with uvc capture)
--------------------------------------------------------------------
		upstream 		| patched
		irq time(us)		| irq time(us)
--------------------------------------------------------------------
Pandaboard A1:  (avg:445, max:873)	| (avg:33, max:44)
Arndale board:  (avg:316, max:630)	| (avg:20, max:27)
T410: 		(avg:39,  max:107)	| (avg:10, max:65)
---------------------------------------------------------------------

2.4 test case4: one uvc streaming plus one mass storage device test
--------------------------------------------------------------------
		upstream 		| patched
		perf(MB/s)+irq time(us)	| perf(MB/s)+irq time(us)
--------------------------------------------------------------------
Pandaboard A1:  20.340(avg:259,max:1704)| 20.390(avg:24, max:101)
Arndale board:  23.460(avg:124,max:726)	| 23.370(avg:15, max:52)
T410: 		28.520(avg:27, max:169)	| 28.630(avg:13, max:160)
---------------------------------------------------------------------

2.5 test case5: read single mass storage device with small transfer
- run below command 10 times and compute the average speed

 dd if=/dev/sdN iflag=direct of=/dev/null bs=4K count=4000

1), test device A:
--------------------------------------------------------------------
		upstream 		| patched
		perf(MB/s)+irq time(us)	| perf(MB/s)+irq time(us)
--------------------------------------------------------------------
Pandaboard A1:  6.5(avg:21, max:64)	| 6.5(avg:10, max:24)
Arndale board:  8.13(avg:12, max:23)	| 8.06(avg:7,  max:17)
T410: 		6.66(avg:13, max:131)   | 6.84(avg:11, max:149)
---------------------------------------------------------------------

2), test device B:
--------------------------------------------------------------------
		upstream 		| patched
		perf(MB/s)+irq time(us)	| perf(MB/s)+irq time(us)
--------------------------------------------------------------------
Pandaboard A1:  5.5(avg:21,max:43)	| 5.49(avg:10, max:24)
Arndale board:  5.9(avg:12, max:22)	| 5.9(avg:7, max:17)
T410: 		5.48(avg:13, max:155)	| 5.48(avg:7, max:140)
---------------------------------------------------------------------

* On T410, sometimes read ehci status register in ehci_irq takes more
than 100us, and the problem has been reported on the link:

	http://marc.info/?t=137065867300001&r=1&w=2

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 11:43:49 -07:00
Ming Lei 9118f9eb4f USB: EHCI: improve interrupt qh unlink
ehci-hcd currently unlinks an interrupt QH when it becomes empty, that
is, after its last URB completes.  This works well because in almost
all cases, the completion handler for an interrupt URB resubmits the
URB; therefore the QH doesn't become empty and doesn't get unlinked.

When we start using tasklets for URB completion, this scheme won't work
as well.  The resubmission won't occur until the tasklet runs, which
will be some time after the completion is queued with the tasklet.
During that delay, the QH will be empty and so will be unlinked
unnecessarily.

To prevent this problem, this patch adds a 5-ms time delay before empty
interrupt QHs are unlinked.  Most often, during that time the interrupt
URB will be resubmitted and thus we can avoid unlinking the QH.

Signed-off-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
Ming Lei 35371e4fbc USB: EHCI: improve ehci_endpoint_disable
The patch does the below improvement:

- think QH_STATE_COMPLETING as unlinking state since all URBs on the
endpoint should be in unlinking or unlinked when doing endpoint_disable()

- add "WARN_ON(!list_empty(&qh->qtd_list));" if qh->qh_state is
QH_STATE_LINKED because there shouldn't be any active transfer in qh

- when qh->qh_state is QH_STATE_LINKED, the QH(async or periodic)
should be in its corresponding list, so the search through the async
list isn't necessary.

- unlink periodic QH to speed up unlinking if the QH is in linked
state

Basically, only the last one is related with this patchset because
the assumption of "periodic qh self-unlinks on empty" isn't true
any more when we introduce unlink-wait for periodic qh.

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
Manjunath Goudar 9fc5f24e43 USB: EHCI: make ehci-tegra a separate driver
Separate the Tegra on-chip host controller driver from
ehci-hcd host code so that it can be built as a separate driver module.
This work is part of enabling multi-platform kernels on ARM.

Signed-off-by: Manjunath Goudar <manjunath.goudar@linaro.org>
[swarren, reworked Manjunath's patches to split them more logically,
minor re-order of added lines to better match layout of other split-up
HCD drivers and existing code, add MODULE_DEVICE_TABLE, fix
MODULE_LICENSE, adapted to change in earlier patches which removed the
ehci_driver_overrides addition, removed all PM code and solved circular
dependencies.]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-17 13:54:48 -07:00
Manjunath Goudar 2f3a6b8652 USB: EHCI: export ehci_handshake for ehci-hcd sub-drivers
In order to split ehci-hcd.c into separate modules, handshake() must be
exported. Rename the symbol to add an ehci_ prefix, to avoid any naming
clashes.

Signed-off-by: Manjunath Goudar <manjunath.goudar@linaro.org>
[swarren, split Manjunath's patches more logically, limit this change
to export just handshake()]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-17 13:54:47 -07:00
Arnd Bergmann 843e56c02d USB: EHCI: remove bogus #error
The EHCI host controller driver can be built standalone now,
without enabling any of the available bus glue drivers, so
there is not really a reason to error out here:

drivers/usb/host/ehci-hcd.c:1303:2: error:
 #error "missing bus glue for ehci-hcd"  #error "missing bus glue for ehci-hcd"

The alternative would be to change the Kconfig code to build
the ehci-hcd module only if any of the symbols below are
in fact enabled.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-16 17:29:51 -07:00
Shengzhou Liu 61ac6ac8d6 usb: remove redundant tdi_reset
We remove the redundant tdi_reset in ehci_setup since there
is already it in ehci_reset.
It was observed that the duplicated tdi_reset was causing
the PHY_CLK_VALID bit unstable.

Reported-by: Michael Braun <michael-dev@fami-braun.de>
Signed-off-by: Shengzhou Liu <Shengzhou.Liu@freescale.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@vger.kernel.org> # 3.6+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-17 10:01:22 -07:00
Manjunath Goudar 8c68e84f3a USB: EHCI: make ehci-msm a separate driver
Separate the  Qualcomm QSD/MSM on-chip host controller driver from
ehci-hcd host code so that it can be built as a separate driver module.
This work is part of enabling multi-platform kernels on ARM;
however, note that other changes are still needed before Qualcomm QSD/MSM
can be booted with a multi-platform kernel, which is not expected before
3.11.

With the infrastructure added by Alan Stern in patch 3e0232039
"USB: EHCI: prepare to make ehci-hcd a library module", we can
avoid this problem by turning a bus glue into a separate
module, as we do here for the msm bus glue.

In V5 (arnd):
 - add FIXME about missing usb_add_hcd() or usb_remove_hcd() calls

In V3:
 - Detailed commit message added here describing why this patch is required.
 - Arranged  #include's in alphabetical order.
 - driver.name initialized hcd_name[] = "ehci-msm" in platform_driver
   structure initialization instead of "msm-ehci", which was the reason
   why it broke in EHCI USB testing

In V2:
Tegra patch related changes removed from this patch.

Signed-off-by: Manjunath Goudar <manjunath.goudar@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: David Brown <davidb@codeaurora.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-08 09:40:20 -07:00
Manjunath Goudar 9773696105 USB: EHCI: make ehci-atmel a separate driver
Separate the Atmel host controller driver from ehci-hcd host code
so that it can be built as a separate driver module.
This work is part of enabling multi-platform kernels on ARM;
however, note that other changes are still needed before Atmel can be
booted with a multi-platform kernel. This is currently planned for
Linux-3.11.

With the infrastructure added by Alan Stern in patch 3e0232039
"USB: EHCI: prepare to make ehci-hcd a library module", we can
avoid this problem by turning a bus glue into a separate
module, as we do here for the Atmel bus glue.

In V4 (arnd):
 - reordered #include statements.
 - removed call to ehci_shutdown and the corresponding export

In V3:
 - Detailed commit message added here about why this patch is required.
 - Replaced hcd_name string "ehci-atmel" to "atmel-ehci".
 - Inserted blank line in the Makefile to separate the EHCI drivers from
   the following non-EHCI drivers.
 - Exported ehci_shutdown symbol as it is needed by the Atmel driver.
 - Eliminated ehci_atmel_setup routine because hcd registers
   can be directly set in the ehci_atmel_drv_probe function.

In V2:
  Resolved below compiler error.
  drivers/usb/host/ehci-atmel.c: In function 'ehci_atmel_drv_remove':
  drivers/usb/host/ehci-atmel.c:167: error: implicit declaration of function 'ehci_shutdown'

Signed-off-by: Manjunath Goudar <manjunath.goudar@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Andrew Victor <linux@maxim.org.za>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-08 09:40:20 -07:00
Manjunath Goudar 7edb3daf78 USB: EHCI: make ehci-s5p a separate driver
Separate the  Samsung S5P/EXYNOS host controller driver from ehci-hcd
host code so that it can be built as a separate driver module.
This work is part of enabling multi-platform kernels on ARM;
however, note that other changes are still needed before S5P/EXYNOS can
be booted with a multi-platform kernel. We currently expect those
to get merged for 3.10.

With the infrastructure added by Alan Stern in patch 3e0232039
"USB: EHCI: prepare to make ehci-hcd a library module", we can
avoid this problem by turning a bus glue into a separate
module, as we do here for the s5p bus glue.

In V4 (arnd)
 - revert some of the pointless changes.
 - fix allocation of s5p specific data structure.

In V3:
 - Detailed commit message added here, why this patch is required.
 - MODULE_LICENSE is GPL v2.
 - Added .extra_priv_size to eliminate the separate allocation of
   the s5p_ehci_hcd structure and removed .reset function pointer
   initialization.
 - Arranged  #include's in alphabetical order.
 - After using extra_priv_size initialization, struct usb_hcd *hcd
   is redundant and can be removed from the probe function.
 - Eliminated s5p_ehci_phy_enable,contents of statements moved
   into the s5p_ehci_probe
 - Eliminated s5p_ehci_phy_disable, contents of statements moved into
   the s5p_ehci_remove.

In V2:
 - Tegra patch related changes removed from this patch.

Signed-off-by: Manjunath Goudar <manjunath.goudar@linaro.org>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-08 09:38:12 -07:00
Manjunath Goudar 7675d6ba43 USB: EHCI: make ehci-spear a separate driver
Separate the SPEAr host controller driver from ehci-hcd host code
so that it can be built as a separate driver module.
This work is part of enabling multi-platform kernels on ARM;
however, note that other changes are still needed before SPEAr can be
booted with a multi-platform kernel, but they are queued in the
arm-soc tree for 3.10.

With the infrastructure added by Alan Stern in patch 3e0232039
"USB: EHCI: prepare to make ehci-hcd a library module", we can
avoid this problem by turning a bus glue into a separate
module, as we do here for the SPEAr bus glue.

In V4 (arnd):
 - renamed all 'struct spear_ehci' pointers from 'ehci' to the
   less ambiguous 'sehci'.
 - folded trivial spear_start_ehci/spear_stop_ehci functions into
   callers.
 - brought back initialization of ehci->caps.

In V3:
 - Detailed commit message added here about why this patch is required.
 - Eliminated ehci_spear_setup routine because hcd registers can
   be directly set in the spear_ehci_hcd_drv_probe function.
 - spear_overrides struct initialized.
 - Converted to using .extra_priv_size for allocating spear_ehci,
   and updated all users of that structure.
 - to_spear_ehci() macro modified for spear_ehci.

In V2:
 - Replaced spear as SPEAr everywhere, leaving functions/variables/config options.

Signed-off-by: Deepak Saxena <dsaxena@linaro.org>
Signed-off-by: Manjunath Goudar <manjunath.goudar@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Viresh Kumar <viresh.linux@gmail.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Shiraz Hashim <shiraz.hashim@st.com>
Cc: spear-devel@list.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-08 09:35:22 -07:00
Manjunath Goudar a76dd463c5 USB: EHCI: make ehci-orion a separate driver
Separate the Orion host controller driver from ehci-hcd host
code into its own driver module because of following reason.

With the multiplatform changes in arm-soc tree, it becomes
possible to enable the mvebu platform (which uses
ehci-orion) at the same time as other platforms that require
a conflicting EHCI bus glue. At the moment, this results
in a warning like

drivers/usb/host/ehci-hcd.c:1297:0: warning: "PLATFORM_DRIVER" redefined [enabled by default]
drivers/usb/host/ehci-hcd.c:1277:0: note: this is the location of the previous definition
drivers/usb/host/ehci-orion.c:334:31: warning: 'ehci_orion_driver' defined but not used [-Wunused-variable]

and an ehci driver that only works on one of them.

With the infrastructure added by Alan Stern in patch 3e0232039
"USB: EHCI: prepare to make ehci-hcd a library module", we can
avoid this problem by turning a bus glue into a separate
module, as we do here for the orion bus glue.

An earlier version of this patch was included in 3.9 but caused
a regression there, which has subsequently been fixed.

While we are here, use the opportunity to disabiguate the two
Marvell EHCI controller implementations in Kconfig.

In V4 (arnd):
- Improve Kconfig text

In V3:
- More detail provided in commit message regarding this patch.
- Replaced hcd_name string "ehci-orion" into "orion-ehci".
- MODULE_LICENSE is GPL v2.
- In ehci_init_driver calling second argument passed  as NULL instead of
  ehci_orion_overrides because ehci_orion_overrides is removed.

In V2:
- Tegra patch related changes removed from this patch.

Signed-off-by: Manjunath Goudar <manjunath.goudar@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-08 09:33:40 -07:00
Arnd Bergmann f3bc64d6d1 USB: EHCI: DT support for generic bus glue
This lets us use the ehci-platform driver on platforms without special
requirements for their ehci controllers. In particular, this is true
for the vt8500/wm8x50 platforms, which currently have a separate
driver that causes problems with multiplatform configurations.

Tested-by: Tony Prisk <linux@prisktech.co.nz>
Tested-by: Peter Vasil <petervasil@gmail.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-28 11:22:15 -07:00
Alan Stern 214ac7a077 USB: EHCI: improve end_unlink_async()
This patch (as1665) changes the way ehci-hcd's end_unlink_async()
routine works in order to avoid recursive execution and to be more
efficient:

	Now when an IAA cycle ends, a new one gets started up right
	away (if it is needed) instead of waiting until the
	just-unlinked QH has been processed.

	The async_iaa list is renamed to async_idle, which better
	expresses its new purpose: It is now the list of QHs which are
	now completely idle and are waiting to be processed by
	end_unlink_async().

	A new flag is added to track whether an IAA cycle is in
	progress, because the list formerly known as async_iaa no
	longer stores the QHs waiting for the IAA to finish.

	The decision about how many QHs to process when an IAA cycle
	ends is now made at the end of the cycle, when we know the
	current state of the hardware, rather than at the beginning.
	This means a bunch of logic got moved from start_iaa_cycle()
	to end_unlink_async().

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-25 13:36:32 -07:00
Alan Stern 6e018751a3 USB: EHCI: convert singly-linked lists to list_heads
This patch (as1664) converts ehci-hcd's async_unlink, async_iaa, and
intr_unlink from singly-linked lists to standard doubly-linked
list_heads.  Originally it didn't seem necessary to use list_heads,
because items are always added to and removed from these lists in FIFO
order.  But now with more list processing going on, it's easier to use
the standard routines than continue with a roll-your-own approach.

I don't know if the code ends up being notably shorter, but the
patterns will be more familiar to any kernel hacker.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-25 13:35:05 -07:00
Alan Stern 7655e3160c USB: EHCI: consolidate code in ehci_urb_dequeue()
This patch (as1668) consolidates two nearly identical code paths in
ehci_urb_dequeue().  The test for !qh can be removed because it will
never succeed; the fact that usb_hcd_check_unlink_urb() returned 0
means that urb must be queued and therefore urb->hcpriv must point to
a QH.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-25 13:35:05 -07:00
Alan Stern 7bc782d73c USB: EHCI: split needs_rescan into two flags
This patch (as1662) does some more QH-related cleanup in ehci-hcd.
The qh->needs_rescan flag is currently used for two different
purposes; the patch replaces it with two separate flags for greater
clarity: qh->dequeue_during_giveback indicates that a completion
handler dequeued an URB (implying that a rescan is needed), and
qh->exception indicates that the QH is in an exceptional state
requiring an unlink (either it encountered an I/O error or an unlink
was requested).

The new flags get set where the dequeue, exception, or unlink request
occurred, rather than where the unlink is started.  This is so that in
the future, if we need to, we will be able to tell apart unlinks that
truly were required from those that were carried out merely because
the QH wasn't being used.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-25 13:35:05 -07:00
Greg Kroah-Hartman cf2d9500a5 Merge branch 'usb-linus' into usb-next
This is to pick up the fixes in that branch, and let Alan fix the merge
error in drivers/usb/host/ehci-timer.c better than I just did (as I know
I messed it up...)

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-20 16:21:47 -07:00
Alan Stern 4dd405a4b0 USB: EHCI: improve use of per-port status-change bits
This patch (as1634) simplifies some of the code associated with the
per-port change bits added in EHCI-1.1, and in particular it fixes a
bug in the logic of ehci_hub_status_data().  Even if the change bit
doesn't indicate anything happened on a particular port, we still have
to notify the core about changes to the suspend or reset status.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-18 16:05:58 -07:00
Alan Stern 2a40f32454 USB: EHCI: fix regression during bus resume
This patch (as1663) fixes a regression caused by commit
6e0c3339a6 (USB: EHCI: unlink one async
QH at a time).  In order to avoid keeping multiple QHs in an unusable
intermediate state, that commit changed unlink_empty_async() so that
it unlinks only one empty QH at a time.

However, when the EHCI root hub is suspended, _all_ async QHs need to
be unlinked.  ehci_bus_suspend() used to do this by calling
unlink_empty_async(), but now this only unlinks one of the QHs, not
all of them.

The symptom is that when the root hub is resumed, USB communications
don't work for some period of time.  This is because ehci-hcd doesn't
realize it needs to restart the async schedule; it assumes that
because some QHs are already on the schedule, the schedule must be
running.

The easiest way to fix the problem is add a new function that unlinks
all the async QHs when the root hub is suspended.

This patch should be applied to all kernels that have the 6e0c3339a6
commit.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: Adrian Bassett <adrian.bassett@hotmail.co.uk>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-15 12:07:53 -07:00
Alan Stern 54a419668b USB: EHCI: split ehci-omap out to a separate driver
This patch (as1645) converts ehci-omap over to the new "ehci-hcd is a
library" approach, so that it can coexist peacefully with other EHCI
platform drivers and can make use of the private area allocated at
the end of struct ehci_hcd.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-15 11:51:45 -07:00
Alan Stern 6402c796d3 USB: EHCI: work around silicon bug in Intel's EHCI controllers
This patch (as1660) works around a hardware problem present in some
(if not all) Intel EHCI controllers.  After a QH has been unlinked
from the async schedule and the corresponding IAA interrupt has
occurred, the controller is not supposed access the QH and its qTDs.
There certainly shouldn't be any more DMA writes to those structures.
Nevertheless, Intel's controllers have been observed to perform a
final writeback to the QH's overlay region and to the most recent qTD.
For more information and a test program to determine whether this
problem is present in a particular controller, see

	http://marc.info/?l=linux-usb&m=135492071812265&w=2
	http://marc.info/?l=linux-usb&m=136182570800963&w=2

This patch works around the problem by always waiting for two IAA
cycles when unlinking an async QH.  The extra IAA delay gives the
controller time to perform its final writeback.

Surprisingly enough, the effects of this silicon bug have gone
undetected until quite recently.  More through luck than anything
else, it hasn't caused any apparent problems.  However, it does
interact badly with the path that follows this one, so it needs to be
addressed.

This is the first part of a fix for the regression reported at:

	https://bugs.launchpad.net/bugs/1088733

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Stephen Thirlwall <sdt@dr.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-05 08:45:33 +08:00
Alan Stern f292e7f9fb USB: EHCI: notify usbcore about port resumes
This patch (as1650) adds calls to the new
usb_hcd_{start,end}_port_resume() functions to ehci-hcd.  Now EHCI
root hubs won't be runtime suspended while they are sending a resume
signal to one of their ports.

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
Alan Stern dba63b2f73 USB: EHCI: fix build error in ehci-mxc
This patch (as1643b) fixes a build error in ehci-hcd when compiling for
ARM with allmodconfig:

drivers/usb/host/ehci-hcd.c:1285:0: warning: "PLATFORM_DRIVER" redefined [enabled by default]
drivers/usb/host/ehci-hcd.c:1255:0: note: this is the location of the previous definition
drivers/usb/host/ehci-mxc.c:280:31: warning: 'ehci_mxc_driver' defined but not used [-Wunused-variable]
drivers/usb/host/ehci-hcd.c:1285:0: warning: "PLATFORM_DRIVER" redefined [enabled by default]
drivers/usb/host/ehci-hcd.c:1255:0: note: this is the location of the previous definition

The fix is to convert ehci-mxc over to the new "ehci-hcd is a library"
scheme so that it can coexist peacefully with the ehci-platform
driver.  As part of the conversion the ehci_mxc_priv data structure,
which was allocated dynamically, is now placed where it belongs: in
the private area at the end of struct ehci_hcd.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-23 11:27:08 -08:00
Alan Stern 9ce45ef86c USB: EHCI: fix incorrect configuration test
This patch (as1641) fixes a minor bug in ehci-hcd left over from when
the Chipidea driver was converted to the "ehci-hcd is a library"
scheme.  The test for whether the Chipidea platform driver is active
should be IS_ENABLED(), not defined().

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-22 09:21:23 -08:00
Roger Quadros 9ec6e9d3cb USB: EHCI: Move definition of EHCI_STATS to ehci.h
Without this, platform drivers e.g. ehci-omap.c will see a
different version of struct ehci_hcd than ehci-hcd.c and
break reference to 'debug_dir' and 'priv' members when
CONFIG_USB_DEBUG is enabled.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-22 09:21:23 -08:00
Alan Stern 1b36810e27 USB: EHCI: miscellaneous cleanups for the library conversion
This patch (as1630) cleans up a few minor items resulting from the
split-up of the ehci-hcd driver:

	Remove the product_desc string from the ehci_driver_overrides
	structure.  All drivers will use the generic "EHCI Host
	Controller" string.  (This was requested by Felipe Balbi.)

	Allow drivers to pass a NULL pointer to ehci_init_driver()
	if they don't have to override any settings.

	Remove a #define symbol that is no longer used from the
	ChipIdea host driver.

	Rename overrides to pci_overrides in ehci-pci.c, for
	consistency with ehci-platform.c.

	Mark the *_overrides structures as __initdata.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-11 18:06:48 -08:00
Alan Stern 09f6ffde2e USB: EHCI: fix build error by making ChipIdea host a normal EHCI driver
This patch (as1627) splits the ehci-hcd core code, which has become a
separate library module, out from the ChipIdea host driver.  Instead
of #include-ing ehci-hcd.c directly, the ChipIdea module will now use
the ehci-hcd library in a normal fashion.

This fixes a build error caused by commit
3e02320399 (USB: EHCI: prepare to make
ehci-hcd a library module); I had forgotten about the unorthodox way
the ChipIdea driver uses the ehci-hcd code.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-02 10:03:50 -07:00
Alan Stern 99f91934a9 USB: EHCI: make ehci-platform a separate driver
This patch (as1626) splits the ehci-platform code from ehci-hcd out
into its own separate driver module.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-01 08:51:13 -07:00
Alan Stern adfa79d1c0 USB: EHCI: make ehci-pci a separate driver
This patch (as1625) splits the PCI portion of ehci-hcd out into its
own separate driver module, called ehci-pci.  Consistently with the
current practice, the decision whether to build this module is not
user-configurable.  If EHCI and PCI are enabled then the module will
be built, always.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-01 08:51:12 -07:00
Alan Stern 3e02320399 USB: EHCI: prepare to make ehci-hcd a library module
This patch (as1624) prepares ehci-hcd for being split up into a core
library and separate platform driver modules.  A generic
ehci_hc_driver structure is created, containing all the "standard"
values, and a new mechanism is added whereby a driver module can
specify a set of overrides to those values.  In addition the
ehci_setup(), ehci_suspend(), and ehci_resume() routines need to be
EXPORTed for use by the drivers.

As a side effect of this change, a few routines no longer need to be
marked __maybe_unused.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-01 08:51:12 -07:00
Alan Stern c73cee717e USB: EHCI: remove ehci_port_power() routine
This patch (as1623) removes the ehci_port_power() routine and all the
places that call it.  There's no reason for ehci-hcd to change the
port power settings; the hub driver takes care of all that stuff.

There is one exception: When the controller is resumed from
hibernation or following a loss of power, the ports that are supposed
to be handed over to a companion controller must be powered on first.
Otherwise the handover won't work.  This process is not visible to the
hub driver, so it has to be handled in ehci-hcd.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-31 12:48:07 -07:00
Alan Stern 4968f95191 USB: EHCI: remove unused Link Power Management code
This patch (as1622) removes the USB-2.1 Link Power Management code
from the ehci-hcd driver.  This code was never integrated with
usbcore, it is full of bugs, and it was not getting used by anybody.

However, the debugging code for dumping the LPM-related fields in the
EHCI registers is left in place.  In theory it might be useful to see
these values, even though we don't use them.

This essentially amounts to a partial revert of commit
aa4d834298 (USB: EHCI: EHCI 1.1
addendum: preparation) and an almost full revert of commit
48f2497014 (USB: EHCI: EHCI 1.1
addendum: Basic LPM feature support) plus its follow-ons.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-31 12:48:07 -07:00
Alan Stern acc0850340 USB: EHCI: make ehci_read_frame_index platform independent
In preparation for splitting the ehci-hcd driver into a core library
and separate platform-specific driver modules, this patch (as1617)
changes the way ehci_read_frame_index() is handled.

Since the same core library will have to work with both PCI and
non-PCI platforms, the quirk handler routine will be compiled
unconditionally.  The decision about whether to call it or simply to
read the frame index register is made at run time, based on whether
the frame_index_bug quirk flag is set.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24 14:45:17 -07:00
Florian Fainelli f3a958d30d USB: EHCI: remove CNS3xxx EHCI platform driver
The users have been converted to use the ehci platform driver instead, thus
making the ehci-cns3xxx driver obsolete, so remove it.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-22 11:23:58 -07:00
Florian Fainelli 1de7d89c76 USB: EHCI: remove Alchemy EHCI driver
The platform code has been converted to use the ehci-platform driver instead
thus obsoleting the ehci-au1xxx driver, which can be removed.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-22 11:23:57 -07:00
Florian Fainelli 6d39944ee8 USB: EHCI: remove Netlogic XLS EHCI driver
The platform code has been migrated to register the ehci-platform driver, thus
obsoleting the ehci-xls driver, which can be removed.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-22 11:15:47 -07:00
Florian Fainelli ead92fae12 USB: EHCI: remove Loongson 1B EHCI driver.
The platform code registering the Loongson 1B EHCI driver has now been
converted to register the ehci-platform driver instead, thus obsoleting the
ehci-ls1x driver, which can be removed.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-22 11:14:24 -07:00
Florian Fainelli 6efd0f73cc USB: EHCI: remove IXP4xx EHCI driver
This driver is not registered by any in-tree user. If needed it the EHCI
driver can be reinstatied using the ehci-platform driver with caps_offset to
0x100.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-22 11:14:24 -07:00
Alan Stern 98cae42d82 EHCI: use the isochronous scheduling threshold
This patch (as1609) changes the way ehci-hcd uses the "Isochronous
Scheduling Threshold" in its calculations.  Until now the code has
ignored the threshold except for certain Intel PCI-based controllers.
This violates the EHCI spec.

The new code takes the threshold into account always, removing the
need for the fs_i_thresh quirk flag.  In addition it implements the
"full frame cache" setting more efficiently, moving forward only as
far as the next frame boundary instead of always moving forward 8
microframes.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-22 08:57:43 -07:00
Jan Beulich 9fa5780bee USB EHCI/Xen: propagate controller reset information to hypervisor
Just like for the in-tree early console debug port driver, the
hypervisor - when using a debug port based console - also needs to be
told about controller resets, so it can suppress using and then
re-initialize the debug port accordingly.

Other than the in-tree driver, the hypervisor driver actually cares
about doing this only for the device where the debug is port actually
in use, i.e. it needs to be told the coordinates of the device being
reset (quite obviously, leveraging the addition done for that would
likely benefit the in-tree driver too).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-18 17:20:48 +01:00
Linus Torvalds 9fc377799b USB patches for 3.6-rc1
Here's the big USB patch set for the 3.6-rc1 merge window.
 
 Lots of little changes in here, primarily for gadget controllers and drivers.
 There's some scsi changes that I think also went in through the scsi tree, but
 they merge just fine.  All of these patches have been in the linux-next tree
 for a while now.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB patches from Greg Kroah-Hartman:
 "Here's the big USB patch set for the 3.6-rc1 merge window.

  Lots of little changes in here, primarily for gadget controllers and
  drivers.  There's some scsi changes that I think also went in through
  the scsi tree, but they merge just fine.  All of these patches have
  been in the linux-next tree for a while now.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

Fix up trivial conflicts in include/scsi/scsi_device.h (same libata
conflict that Jeff had already encountered)

* tag 'usb-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (207 commits)
  usb: Add USB_QUIRK_RESET_RESUME for all Logitech UVC webcams
  usb: Add quirk detection based on interface information
  usb: s3c-hsotg: Add header file protection macros in s3c-hsotg.h
  USB: ehci-s5p: Add vbus setup function to the s5p ehci glue layer
  USB: add USB_VENDOR_AND_INTERFACE_INFO() macro
  USB: notify phy when root hub port connect change
  USB: remove 8 bytes of padding from usb_host_interface on 64 bit builds
  USB: option: add ZTE MF821D
  USB: sierra: QMI mode MC7710 moved to qcserial
  USB: qcserial: adding Sierra Wireless devices
  USB: qcserial: support generic Qualcomm serial ports
  USB: qcserial: make probe more flexible
  USB: qcserial: centralize probe exit path
  USB: qcserial: consolidate usb_set_interface calls
  USB: ehci-s5p: Add support for device tree
  USB: ohci-exynos: Add support for device tree
  USB: ehci-omap: fix compile failure(v1)
  usb: host: tegra: pass correct pointer in ehci_setup()
  USB: ehci-fsl: Update ifdef check to work on 64-bit ppc
  USB: serial: keyspan: Removed unrequired parentheses.
  ...
2012-07-26 10:23:47 -07:00
Chris Metcalf 47fc28bff8 usb: add host support for the tilegx architecture
This change adds OHCI and EHCI support for the tilegx's on-chip
USB hardware.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2012-07-18 16:40:29 -04:00
Alan Stern 43fe3a99d9 USB: EHCI: resolve some unlikely races
This patch (as1589) resolves some unlikely races involving system
shutdown or controller death in ehci-hcd:

	Shutdown races with both root-hub resume and controller
	resume.

	Controller death races with root-hub suspend.

A new bitflag is added to indicate that the controller has been shut
down (whether for system shutdown or because it died).  Tests are
added in the suspend and resume pathways to avoid reactivating the
controller after any sort of shutdown.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16 16:56:48 -07:00
Alan Stern c4f3476436 USB: EHCI: fix up locking
This patch (as1588) adjusts the locking in ehci-hcd's various halt,
shutdown, and suspend/resume pathways.  We want to hold the spinlock
while writing device registers and accessing shared variables, but not
while polling in a loop.

In addition, there's no need to call ehci_work() at times when no URBs
can be active, i.e., in ehci_stop() and ehci_bus_suspend().

Finally, ehci_adjust_port_wakeup_flags() is called only in situations
where interrupts are enabled; therefore it can use spin_lock_irq
rather than spin_lock_irqsave.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16 16:56:48 -07:00
Alan Stern f428907822 USB: EHCI: simplify isochronous scanning
This patch (as1587) simplifies ehci-hcd's scan_isoc() routine by
eliminating some local variables, declaring boolean-valued values as
bool rather than unsigned, changing variable names to make more sense,
and so on.

The logic at the end of the routine is cut down significantly.  The
scanning doesn't have to catch up all the way to where the hardware
is; it merely has to catch up to where the hardware was when the last
interrupt occurred.  If the hardware has made more progress since then
and issued another interrupt, a rescan will catch up to it.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16 16:56:47 -07:00
Alan Stern 18aafe64d7 USB: EHCI: use hrtimer for the I/O watchdog
This patch (as1586) replaces the kernel timer used by ehci-hcd as an
I/O watchdog with an hrtimer event.

Unlike in the current code, the watchdog event is now always enabled
whenever any isochronous URBs are active.  This will prevent bugs
caused by the periodic schedule wrapping around with no completion
interrupts; the watchdog handler is guaranteed to scan the isochronous
transfers at least once during each iteration of the schedule.  The
extra overhead will be negligible: one timer interrupt every 100 ms.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16 16:56:47 -07:00
Alan Stern 569b394f53 USB: EHCI: always scan each interrupt QH
This patch (as1585) fixes a bug in ehci-hcd's scheme for scanning
interrupt QHs.

Currently a single routine takes care of scanning everything on the
periodic schedule.  Whenever an interrupt occurs, it scans all
isochronous and interrupt URBs scheduled for frames that have elapsed
since the last scan.

This has two disadvantages.  The first is relatively minor: An
interrupt QH is likely to end up getting scanned multiple times,
particularly if the last scan was not fairly recent.  (The current
code avoids this by maintaining a periodic_stamp in each interrupt
QH.)

The second is more serious.  The periodic schedule wraps around.  If
the last scan occurred during frame N, and the next scan occurs when
the schedule has gone through an entire cycle and is back at frame N,
the scanning code won't look at any frames other than N.  Consequently
it won't see any QHs that completed during frame N-1 or earlier.

The patch replaces the entire frame-based approach for scanning
interrupt QHs with a new routine using a list-based approach, the same
as for async QHs.  This has a slight disadvantage, because it means
that all interrupt QHs have to be scanned every time.  But it is more
robust than the current approach.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16 16:56:47 -07:00
Alan Stern 361aabf395 USB: EHCI: don't lose events during a scan
This patch (as1584) fixes a minor bug that has been present in
ehci-hcd since the beginning.

Scanning the schedules for URB completions is single-threaded.  If a
completion interrupt occurs while an URB is being given back, the
interrupt handler realizes that a scan is in progress on another CPU
and avoids starting a new one.

This means that completion events can be lost.  If an URB completes
after it has been scanned but while a scan is still in progress, the
driver won't notice and won't rescan the completed URB.

The patch fixes the problem by adding a new flag to indicate that
another scan is needed after the current scan is done.  The flag gets
set whenever a completion interrupt occurs while a scan is in
progress.  The rescan will see the completion, thus preventing it from
getting lost.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16 16:56:47 -07:00
Alan Stern 32830f2076 USB: EHCI: use hrtimer for unlinking empty async QHs
This patch (as1583) changes ehci-hcd to use an hrtimer event for
unlinking empty (unused) async QHs instead of using a kernel timer.

The check for empty QHs is moved to a new routine, where it doesn't
require going through an entire scan of both the async and periodic
schedules.  And it can unlink multiple QHs at once, unlike the current
code.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16 16:56:47 -07:00