linux-toradex.git/drivers/usb/host/ehci-hcd.c, branch v2.6.32.35

USB: EHCI: fix DMA deallocation bug

2011-02-17T23:36:47+00:00

commit f75593ceaa08e6d27aec1a5de31cded19e850dd1 upstream.

This patch (as1440) fixes a bug in ehci-hcd.  ehci->periodic_size is
used to compute the size in a dma_alloc_coherent() call, but then it
gets changed later on.  As a result, the corresponding call to
dma_free_coherent() passes a different size from the original
allocation.  Fix the problem by adjusting ehci->periodic_size before
carrying out any of the memory allocations.

Signed-off-by: Alan Stern 
Tested-by: Larry Finger 
CC: David Brownell 
Signed-off-by: Greg Kroah-Hartman

USB: EHCI: ASPM quirk of ISOC on AMD SB800

2011-02-17T23:36:42+00:00

commit 05570297ecbe834b1756b522412b68eaffb9ab11 upstream.

When ASPM PM Feature is enabled on UMI link, devices that use ISOC stream of
data transfer may be exposed to longer latency causing less than optimal per-
formance of the device. The longer latencies are normal and are due to link
wake time coming out of low power state which happens frequently to save
power when the link is not active.
The following code will make exception for certain features of ASPM to be by
passed and keep the logic normal state only when the ISOC device is connected
and active. This change will allow the device to run at optimal performance
yet minimize the impact on overall power savings.

Signed-off-by: Alex He 
Acked-by: David Brownell 
Signed-off-by: Greg Kroah-Hartman

USB: EHCI: fix obscure race in ehci_endpoint_disable

2010-12-09T21:26:56+00:00

commit 02e2c51ba3e80acde600721ea784c3ef84da5ea1 upstream.

This patch (as1435) fixes an obscure and unlikely race in ehci-hcd.
When an async URB is unlinked, the corresponding QH is removed from
the async list.  If the QH's endpoint is then disabled while the URB
is being given back, ehci_endpoint_disable() won't find the QH on the
async list, causing it to believe that the QH has been lost.  This
will lead to a memory leak at best and quite possibly to an oops.

The solution is to trust usbcore not to lose track of endpoints.  If
the QH isn't on the async list then it doesn't need to be taken off
the list, but the driver should still wait for the QH to become IDLE
before disabling it.

In theory this fixes Bugzilla #20182.  In fact the race is so rare
that it's not possible to tell whether the bug is still present.
However, adding delays and making other changes to force the race
seems to show that the patch works.

Signed-off-by: Alan Stern 
Reported-by: Stefan Richter 
CC: David Brownell 
Signed-off-by: Greg Kroah-Hartman

USB: EHCI: defer reclamation of siTDs

2010-05-12T21:56:59+00:00

commit 0e5f231bc16ff9910882fa5b9d64d80e7691cfab upstream.

This patch (as1369) fixes a problem in ehci-hcd.  Some controllers
occasionally run into trouble when the driver reclaims siTDs too
quickly.  This can happen while streaming audio; it causes the
controller to crash.

The patch changes siTD reclamation to work the same way as iTD
reclamation: Completed siTDs are stored on a list and not reused until
at least one frame has passed.

Signed-off-by: Alan Stern 
Tested-by: Nate Case 
Signed-off-by: Greg Kroah-Hartman

USB: EHCI: adjust ehci_iso_stream for changes in ehci_qh

2010-04-01T22:58:32+00:00

commit 1082f57abfa26590b60c43f503afb24102a37016 upstream.

The EHCI driver stores in usb_host_endpoint.hcpriv a pointer to either
an ehci_qh or an ehci_iso_stream structure, and uses the contents of the
hw_info1 field to distinguish the two cases.

After ehci_qh was split into hw and sw parts, ehci_iso_stream must also
be adjusted so that it again looks like an ehci_qh structure.

This fixes a NULL pointer access in ehci_endpoint_disable() when it
tries to access qh->hw->hw_info1.

Signed-off-by: Clemens Ladisch 
Reported-by: Colin Fletcher 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

USB: add missing delay during remote wakeup

2010-01-25T18:49:33+00:00

commit 49d0f078f494b9d81e820a13dd8093a9bfb0b6b1 upstream.

This patch (as1330) fixes a bug in khbud's handling of remote
wakeups.  When a device sends a remote-wakeup request, the parent hub
(or the host controller driver, for directly attached devices) begins
the resume sequence and notifies khubd when the sequence finishes.  At
this point the port's SUSPEND feature is automatically turned off.

However the device needs an additional 10-ms resume-recovery time
(TRSMRCY in the USB spec).  Khubd does not wait for this delay if the
SUSPEND feature is off, and as a result some devices fail to behave
properly following a remote wakeup.  This patch adds the missing
delay to the remote-wakeup path.

It also extends the resume-signalling delay used by ehci-hcd and
uhci-hcd from 20 ms (the value in the spec) to 25 ms (the value we use
for non-remote-wakeup resumes).  The extra time appears to help some
devices.

Signed-off-by: Alan Stern 
Cc: Rickard Bellini 
Signed-off-by: Greg Kroah-Hartman

USB: work around for EHCI with quirky periodic schedules

2009-12-01T00:43:16+00:00

a quirky chipset needs periodic schedules to run for a minimum
time before they can be disabled again. This enforces the requirement
with a time stamp and a calculated delay

Signed-off-by: Oliver Neukum 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

USB: ehci-dbgp,ehci: Allow early or late use of the dbgp device

2009-09-23T13:46:38+00:00

If the EHCI debug port is initialized and in use, the EHCI host
controller driver must follow two rules.

1) If the EHCI host driver issues a controller reset, the debug
   controller driver re-initialization must get called after the reset
   is completed.

2) The EHCI host driver should ignore any requests to the physical
   EHCI debug port when the EHCI debug port is in use.

The code to check for the debug port was moved from ehci_pci_reinit()
to ehci_pci_setup because it must get called prior to ehci_reset()
which will clear the debug port registers.

Signed-off-by: Jason Wessel 
Cc: Alan Stern 
Cc: dbrownell@users.sourceforge.net
Cc: Ingo Molnar 
Cc: Andrew Morton 
Cc: Yinghai Lu 
Cc: "Eric W. Biederman" 
Signed-off-by: Greg Kroah-Hartman

USB: EHCI: change deschedule logic for interrupt QHs

2009-09-23T13:46:37+00:00

This patch (as1281) changes the way ehci-hcd deschedules interrupt
QHs, copying the approach used for async QHs.  The caller is no longer
responsible for rescheduling the QH if its queue is non-empty; instead
the reschedule is done directly by intr_deschedule(), after calling
qh_completions().  This is exactly the same as how end_unlink_async()
works.

ehci_urb_dequeue() and intr_deschedule() now correctly handle the case
where they are called while another interrupt URB for the same QH is
being given back.  This was a surprisingly large blind spot.  And
scan_periodic() now respects the new needs_rescan flag.

Signed-off-by: Alan Stern 
CC: David Brownell 
Signed-off-by: Greg Kroah-Hartman

USB: EHCI: rescan the queue after an unlink

2009-09-23T13:46:37+00:00

This patch (as1280) fixes an obscure bug in ehci-hcd's dequeuing logic
for async URBs.  If a later URB is unlinked and the completion
routine unlinks an earlier URB, then the earlier URB won't be given
back in a timely manner because the endpoint queue isn't rescanned as
it should be.

Similar bugs occur if an endpoint is reset or a halt is cleared while
a completion routine is running, because the subroutines don't test
for the COMPLETING state.

All these problems are solved by adding a new needs_rescan flag to the
ehci_qh structure.  If the flag is set while scanning through an idle
QH, the scan will be repeated.  If the QH isn't idle then an unlink
cycle will be initiated, and the proper action will be taken when it
becomes idle.

Also, an unnecessary test is removed from qh_link_async(): That
routine is never called if the QH's state isn't IDLE.

Signed-off-by: Alan Stern 
CC: David Brownell 
Signed-off-by: Greg Kroah-Hartman