linux-stable.git/drivers/usb/host, branch linux-3.8.y

xhci: Don't warn on empty ring for suspended devices.

2013-05-11T20:53:53+00:00

commit a83d6755814e4614ba77e15d82796af0f695c6b8 upstream.

When a device attached to the roothub is suspended, the endpoint rings
are stopped.  The host may generate a completion event with the
completion code set to 'Stopped' or 'Stopped Invalid' when the ring is
halted.  The current xHCI code prints a warning in that case, which can
be really annoying if the USB device is coming into and out of suspend.

Remove the unnecessary warning.

Signed-off-by: Sarah Sharp 
Tested-by: Stephen Hemminger 
Cc: Luis Henriques 
Signed-off-by: Greg Kroah-Hartman

usb: remove redundant tdi_reset

2013-05-08T03:08:18+00:00

commit 61ac6ac8d662ac7ac67c864954d39d1b19948354 upstream.

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 
Signed-off-by: Shengzhou Liu 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

usb: xhci: Fix TRB transfer length macro used for Event TRB.

2013-04-05T16:26:00+00:00

commit 1c11a172cb30492f5f6a82c6e118fdcd9946c34f upstream.

Use proper macro while extracting TRB transfer length from
Transfer event TRBs. Adding a macro EVENT_TRB_LEN (bits 0:23)
for the same, and use it instead of TRB_LEN (bits 0:16) in
case of event TRBs.

This patch should be backported to kernels as old as 2.6.31, that
contain the commit b10de142119a676552df3f0d2e3a9d647036c26a "USB: xhci:
Bulk transfer support".  This patch will have issues applying to older
kernels.

Signed-off-by: Vivek gautam 
Signed-off-by: Sarah Sharp 
Signed-off-by: Greg Kroah-Hartman

USB: EHCI: fix bug in iTD/siTD DMA pool allocation

2013-04-05T16:26:00+00:00

commit 85ecd0322b9a1a9f451d9150e9460ab42fd17219 upstream.

[Description written by Alan Stern]

Soeren tracked down a very difficult bug in ehci-hcd's DMA pool
management of iTD and siTD structures.  Some background: ehci-hcd
gives each isochronous endpoint its own set of active and free itd's
(or sitd's for full-speed devices).  When a new itd is needed, it is
taken from the head of the free list, if possible.  However, itd's
must not be used twice in a single frame because the hardware
continues to access the data structure for the entire duration of a
frame.  Therefore if the itd at the head of the free list has its
"frame" member equal to the current value of ehci->now_frame, it
cannot be reused and instead a new itd is allocated from the DMA pool.
The entries on the free list are not released back to the pool until
the endpoint is no longer in use.

The bug arises from the fact that sometimes an itd can be moved back
onto the free list before itd->frame has been set properly.  In
Soeren's case, this happened because ehci-hcd can allocate one more
itd than it actually needs for an URB; the extra itd may or may not be
required depending on how the transfer aligns with a frame boundary.
For example, an URB with 8 isochronous packets will cause two itd's to
be allocated.  If the URB is scheduled to start in microframe 3 of
frame N then it will require both itds: one for microframes 3 - 7 of
frame N and one for microframes 0 - 2 of frame N+1.  But if the URB
had been scheduled to start in microframe 0 then it would require only
the first itd, which could cover microframes 0 - 7 of frame N.  The
second itd would be returned to the end of the free list.

The itd allocation routine initializes the entire structure to 0, so
the extra itd ends up on the free list with itd->frame set to 0
instead of a meaningful value.  After a while the itd reaches the head
of the list, and occasionally this happens when ehci->now_frame is
equal to 0.  Then, even though it would be okay to reuse this itd, the
driver thinks it must get another itd from the DMA pool.

For as long as the isochronous endpoint remains in use, this flaw in
the mechanism causes more and more itd's to be taken slowly from the
DMA pool.  Since none are released back, the pool eventually becomes
exhausted.

This reuslts in memory allocation failures, which typically show up
during a long-running audio stream.  Video might suffer the same
effect.

The fix is very simple.  To prevent allocations from the pool when
they aren't needed, make sure that itd's sent back to the free list
prematurely have itd->frame set to an invalid value which can never be
equal to ehci->now_frame.

This should be applied to -stable kernels going back to 3.6.

Signed-off-by: Soeren Moch 
Signed-off-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

USB: EHCI: fix regression in QH unlinking

2013-03-28T19:18:02+00:00

commit d714aaf649460cbfd5e82e75520baa856b4fa0a0 upstream.

This patch (as1670) fixes a regression caused by commit
6402c796d3b4205d3d7296157956c5100a05d7d6 (USB: EHCI: work around
silicon bug in Intel's EHCI controllers).  The workaround goes through
two IAA cycles for each QH being unlinked.  During the first cycle,
the QH is not added to the async_iaa list (because it isn't fully gone
from the hardware yet), which means that list will be empty.

Unfortunately, I forgot to update the IAA watchdog timer routine.  It
thinks that an empty async_iaa list means the timer expiration was an
error, which isn't true any more.  This problem didn't show up during
initial testing because the controllers being tested all had working
IAA interrupts.  But not all controllers do, and when the watchdog
timer expires, the empty-list check prevents the second IAA cycle from
starting.  As a result, URB unlinks never complete.  The check needs
to be removed.

Among the symptoms of the regression are processes stuck in D wait
states and hangs during system shutdown.

Signed-off-by: Alan Stern 
Reported-and-tested-by: Stephen Warren 
Reported-and-tested-by: Sven Joachim 
Reported-by: Andreas Bombe 
Signed-off-by: Greg Kroah-Hartman

USB: EHCI: fix regression during bus resume

2013-03-28T19:18:02+00:00

commit 2a40f324541ee61c22146214349c2ce9f5c30bcf upstream.

This patch (as1663) fixes a regression caused by commit
6e0c3339a6f19d748f16091d0a05adeb1e1f822b (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 6e0c3339a6f1
commit.

Signed-off-by: Alan Stern 
Reported-and-tested-by: Adrian Bassett 
Signed-off-by: Greg Kroah-Hartman

USB: xhci: correctly enable interrupts

2013-03-28T19:18:02+00:00

commit 00eed9c814cb8f281be6f0f5d8f45025dc0a97eb upstream.

xhci has its own interrupt enabling routine, which will try to
use MSI-X/MSI if present. So the usb core shouldn't try to enable
legacy interrupts; on some machines the xhci legacy IRQ setting
is invalid.

v3: Be careful to not break XHCI_BROKEN_MSI workaround (by trenn)

Cc: Bjorn Helgaas 
Cc: Oliver Neukum 
Cc: Thomas Renninger 
Cc: Yinghai Lu 
Cc: Frederik Himpe 
Cc: David Haerdeman 
Cc: Alan Stern 
Acked-by: Sarah Sharp 
Reviewed-by: Thomas Renninger 
Signed-off-by: Hannes Reinecke 
Signed-off-by: Greg Kroah-Hartman

USB: xhci - fix bit definitions for IMAN register

2013-03-28T19:18:02+00:00

commit f8264340e694604863255cc0276491d17c402390 upstream.

According to XHCI specification (5.5.2.1) the IP is bit 0 and IE is bit 1
of IMAN register. Previously their definitions were reversed.

Even though there are no ill effects being observed from the swapped
definitions (because IMAN_IP is RW1C and in legacy PCI case we come in
with it already set to 1 so it was clearing itself even though we were
setting IMAN_IE instead of IMAN_IP), we should still correct the values.

This patch should be backported to kernels as old as 2.6.36, that
contain the commit 4e833c0b87a30798e67f06120cecebef6ee9644c "xhci: don't
re-enable IE constantly".

Signed-off-by: Dmitry Torokhov 
Signed-off-by: Sarah Sharp 
Signed-off-by: Greg Kroah-Hartman

USB: EHCI: work around silicon bug in Intel's EHCI controllers

2013-03-28T19:17:06+00:00

commit 6402c796d3b4205d3d7296157956c5100a05d7d6 upstream.

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 
Tested-by: Stephen Thirlwall 
Signed-off-by: Greg Kroah-Hartman

USB: EHCI: don't check DMA values in QH overlays

2013-03-20T20:10:53+00:00

commit feca7746d5d9e84b105a613b7f3b6ad00d327372 upstream.

This patch (as1661) fixes a rather obscure bug in ehci-hcd.  In a
couple of places, the driver compares the DMA address stored in a QH's
overlay region with the address of a particular qTD, in order to see
whether that qTD is the one currently being processed by the hardware.
(If it is then the status in the QH's overlay region is more
up-to-date than the status in the qTD, and if it isn't then the
overlay's value needs to be adjusted when the QH is added back to the
active schedule.)

However, DMA address in the overlay region isn't always valid.  It
sometimes will contain a stale value, which may happen by coincidence
to be equal to a qTD's DMA address.  Instead of checking the DMA
address, we should check whether the overlay region is active and
valid.  The patch tests the ACTIVE bit in the overlay, and clears this
bit when the overlay becomes invalid (which happens when the
currently-executing URB is unlinked).

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

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

Signed-off-by: Alan Stern 
Reported-by: Joseph Salisbury 
Reported-and-tested-by: Stephen Thirlwall 
Signed-off-by: Greg Kroah-Hartman