This patch (as1533) fixes a race between root-hub suspend and remote
wakeup.  If a wakeup event occurs while a root hub is suspending, it
might not cause the suspend to fail.  Although the host controller
drivers check for pending wakeup events at the start of their
bus_suspend routines, they generally do not check for wakeup events
while the routines are running.

In addition, if a wakeup event occurs any time after khubd is frozen
and before the root hub is fully suspended, it might not cause a
system sleep transition to fail.  For example, the host controller
drivers do not fail root-hub suspends when a connect-change event is
pending.

To fix both these issues, this patch causes hcd_bus_suspend() to query
the controller driver's hub_status_data method after a root hub is
suspended, if the root hub is enabled for wakeup.  Any pending status
changes will count as wakeup events, causing the root hub to be
resumed and the overall suspend to fail with -EBUSY.

A significant point is that not all events are reflected immediately
in the status bits.  Both EHCI and UHCI controllers notify the CPU
when remote wakeup begins on a port, but the port's suspend-change
status bit doesn't get set until after the port has completed the
transition out of the suspend state, some 25 milliseconds later.
Consequently, the patch will interpret any nonzero return value from
hub_status_data as indicating a pending event, even if none of the
status bits are set in the data buffer.  Follow-up patches make the
necessary changes to ehci-hcd and uhci-hcd.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
CC: Sarah Sharp <sarah.a.sharp@linux.intel.com>
CC: Chen Peter-B29397 <B29397@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

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: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Intel has a PCI USB xhci host controller on a new platform. It doesn't
have a line IRQ definition in BIOS.  The Linux driver refuses to
initialize this controller, but Windows works well because it only depends
on MSI.

Actually, Linux also can work for MSI.  This patch avoids the line IRQ
checking for USB3 HCDs in usb core PCI probe.  It allows the xHCI driver
to try to enable MSI or MSI-X first.  It will fail the probe if MSI
enabling failed and there's no legacy PCI IRQ.

This patch should be backported to kernels as old as 2.6.32.
Signed-off-by: NAlex Shi <alex.shi@intel.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org

This patch is in succession of previous patch
commit c8421147
        xHCI: Adding #define values used for hub descriptor

Hub descriptors characteristics #defines values are added in
hub_configure() in place of magic numbers as asked by Alan Stern.
And the indentation for switch and case is changed to be same.

Some #defines values are added in ch11.h for defining hub class
protocols and used in hub.c and hcd.c in which magic values were
used for hub class protocols.
Signed-off-by: NAman Deep <amandeep3986@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Add a new field num_mapped_sgs to struct urb so that we have a place to
store the number of mapped entries and can also retain the original
value of entries in num_sgs.  Previously, usb_hcd_map_urb_for_dma()
would overwrite this with the number of mapped entries, which would
break dma_unmap_sg() because it requires the original number of entries.

This fixes warnings like the following when using USB storage devices:
 ------------[ cut here ]------------
 WARNING: at lib/dma-debug.c:902 check_unmap+0x4e4/0x695()
 ehci_hcd 0000:00:12.2: DMA-API: device driver frees DMA sg list with different entry count [map count=4] [unmap count=1]
 Modules linked in: ohci_hcd ehci_hcd
 Pid: 0, comm: kworker/0:1 Not tainted 3.2.0-rc2+ #319
 Call Trace:
  <IRQ>  [<ffffffff81036d3b>] warn_slowpath_common+0x80/0x98
  [<ffffffff81036de7>] warn_slowpath_fmt+0x41/0x43
  [<ffffffff811fa5ae>] check_unmap+0x4e4/0x695
  [<ffffffff8105e92c>] ? trace_hardirqs_off+0xd/0xf
  [<ffffffff8147208b>] ? _raw_spin_unlock_irqrestore+0x33/0x50
  [<ffffffff811fa84a>] debug_dma_unmap_sg+0xeb/0x117
  [<ffffffff8137b02f>] usb_hcd_unmap_urb_for_dma+0x71/0x188
  [<ffffffff8137b166>] unmap_urb_for_dma+0x20/0x22
  [<ffffffff8137b1c5>] usb_hcd_giveback_urb+0x5d/0xc0
  [<ffffffffa0000d02>] ehci_urb_done+0xf7/0x10c [ehci_hcd]
  [<ffffffffa0001140>] qh_completions+0x429/0x4bd [ehci_hcd]
  [<ffffffffa000340a>] ehci_work+0x95/0x9c0 [ehci_hcd]
  ...
 ---[ end trace f29ac88a5a48c580 ]---
 Mapped at:
  [<ffffffff811faac4>] debug_dma_map_sg+0x45/0x139
  [<ffffffff8137bc0b>] usb_hcd_map_urb_for_dma+0x22e/0x478
  [<ffffffff8137c494>] usb_hcd_submit_urb+0x63f/0x6fa
  [<ffffffff8137d01c>] usb_submit_urb+0x2c7/0x2de
  [<ffffffff8137dcd4>] usb_sg_wait+0x55/0x161
Signed-off-by: NClemens Ladisch <clemens@ladisch.de>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

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: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

To add USB 3.0 link power management (LPM), we need to know what the U1
and U2 exit latencies are for the xHCI host controller.  External USB 3.0
hubs report these values through the SuperSpeed Capabilities descriptor in
the BOS descriptor.  Make the USB 3.0 roothub for the xHCI host behave
like an external hub and return the BOS descriptors.

The U1 and U2 exit latencies will vary across each host controller, so we
need to dynamically fill those values in by reading the exit latencies out
of the xHC registers.  Make the roothub code in the USB core handle
hub_control() returning the length of the data copied.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1487) improves the usbcore debugging output for port
suspend and bus suspend, by stating whether or not remote wakeup is
enabled.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

This patch (as1486) implements the kernel's new wakeup policy for USB
host controllers.  Since they don't generate wakeup requests on their
but merely forward requests from their root hubs toward the CPU, they
should be enabled for wakeup by default.

Also, to be compliant with both the old and new policies, root hubs
should not be enabled for remote wakeup by default.  Userspace must
enable it explicitly if it is desired.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1482) adds a macro for testing whether or not a
pm_message value represents an autosuspend or autoresume (i.e., a
runtime PM) event.  Encapsulating this notion seems preferable to
open-coding the test all over the place.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>

usb_ifnum_to_if() can return NULL if the USB device does not have a
configuration installed (usb_device->actconfig == NULL), or if we can't
find the interface number in the installed configuration.  Return an
error instead of crashing.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The "authorized_default" module parameter of usbcore controls the default
for the authorized_default variable of each USB host controller.
-1 is authorized for all devices except wireless (default, old behaviour)
0 is unauthorized for all devices
1 is authorized for all devices
Signed-off-by: NCarl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1467) removes the last usages of hcd->state from
usbcore.  We no longer check to see if an interrupt handler finds that
a controller has died; instead we rely on host controller drivers to
make an explicit call to usb_hc_died().

This fixes a regression introduced by commit
9b37596a (USB: move usbcore away from
hcd->state).  It used to be that when a controller shared an IRQ with
another device and an interrupt arrived while hcd->state was set to
HC_STATE_HALT, the interrupt handler would be skipped.  The commit
removed that test; as a result the current code doesn't skip calling
the handler and ends up believing the controller has died, even though
it's only temporarily stopped.  The solution is to ignore HC_STATE_HALT
following the handler's return.

As a consequence of this change, several of the host controller
drivers need to be modified.  They can no longer implicitly rely on
usbcore realizing that a controller has died because of hcd->state.
The patch adds calls to usb_hc_died() in the appropriate places.

The patch also changes a few of the interrupt handlers.  They don't
expect to be called when hcd->state is equal to HC_STATE_HALT, even if
the controller is still alive.  Early returns were added to avoid any
confusion.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Tested-by: NManuel Lauss <manuel.lauss@googlemail.com>
CC: Rodolfo Giometti <giometti@linux.it>
CC: Olav Kongas <ok@artecdesign.ee>
CC: <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

If USB type detections fails, we run into default and return 0.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

If I unplug a device while the UAS driver is loaded, I get an oops
in usb_free_streams().  This is because usb_unbind_interface() calls
usb_disable_interface() which calls usb_disable_endpoint() which sets
ep_out and ep_in to NULL.  Then the UAS driver calls usb_pipe_endpoint()
which returns a NULL pointer and passes an array of NULL pointers to
usb_free_streams().

I think the correct fix for this is to check for the NULL pointer
in usb_free_streams() rather than making the driver check for this
situation.  My original patch for this checked for dev->state ==
USB_STATE_NOTATTACHED, but the call to usb_disable_interface() is
conditional, so not all drivers would want this check.

Note from Sarah Sharp: This patch does avoid a potential dereference,
but the real fix (which will be implemented later) is to set the
.soft_unbind flag in the usb_driver structure for the UAS driver, and
all drivers that allocate streams.  The driver should free any streams
when it is unbound from the interface.  This avoids leaking stream rings
in the xHCI driver when usb_disable_interface() is called.

This should be queued for stable trees back to 2.6.35.
Signed-off-by: NMatthew Wilcox <willy@linux.intel.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@kernel.org

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

The hcd->flags are in a sorry state.  Some of them are clearly specific to
the particular roothub (HCD_POLL_RH, HCD_POLL_PENDING, and
HCD_WAKEUP_PENDING), but some flags are related to PCI device state
(HCD_HW_ACCESSIBLE and HCD_SAW_IRQ).  This is an issue when one PCI device
can have two roothubs that share the same IRQ line and hardware.

Make sure to set HCD_FLAG_SAW_IRQ for both roothubs when an interrupt is
serviced, or an URB is unlinked without an interrupt.  (We can't tell if
the host actually serviced an interrupt for a particular bus, but we can
tell it serviced some interrupt.)

HCD_HW_ACCESSIBLE is set once by usb_add_hcd(), which is set for both
roothubs as they are added, so it doesn't need to be modified.
HCD_POLL_RH and HCD_POLL_PENDING are only checked by the USB core, and
they are never set by the xHCI driver, since the roothub never needs to be
polled.

The usb_hcd's state field is a similar mess.  Sometimes the state applies
to the underlying hardware: HC_STATE_HALT, HC_STATE_RUNNING, and
HC_STATE_QUIESCING.  But sometimes the state refers to the roothub state:
HC_STATE_RESUMING and HC_STATE_SUSPENDED.

Alan Stern recently made the USB core not rely on the hcd->state variable.
Internally, the xHCI driver still checks for HC_STATE_SUSPENDED, so leave
that code in.  Remove all references to HC_STATE_HALT, since the xHCI
driver only sets and doesn't test those variables.  We still have to set
HC_STATE_RUNNING, since Alan's patch has a bug that means the roothub
won't get registered if we don't set that.

Alan's patch made the USB core check a different variable when trying to
determine whether to suspend a roothub.  The xHCI host has a split
roothub, where two buses are registered for one PCI device.  Each bus in
the xHCI split roothub can be suspended separately, but both buses must be
suspended before the PCI device can be suspended.  Therefore, make sure
that the USB core checks HCD_RH_RUNNING() for both roothubs before
suspending the PCI host.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

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: NSarah Sharp <sarah.a.sharp@linux.intel.com>

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: NSarah Sharp <sarah.a.sharp@linux.intel.com>

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: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Refactor out the code in usb_add_hcd() to request the IRQ line for the
HCD.  This will only need to be called once for the two xHCI roothubs, so
it's easier to refactor it into a function, rather than wrapping the long
if-else block into another if statement.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Make the USB 3.0 roothub registered by the USB core have a SuperSpeed
Endpoint Companion Descriptor after the interrupt endpoint.  All USB 3.0
devices are required to have this, and the USB 3.0 bus specification
(section 10.13.1) says which values the descriptor should have.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

We would like to allow host controller drivers to stop using hcd->state.
Unfortunately, some host controller drivers use hcd->state as an
implicit way of telling the core that a controller has died.  The
roothub registration functions must assume the host died if hcd->state
equals HC_STATE_HALT.

To facilitate drivers that don't want to set hcd->state to
HC_STATE_RUNNING in their initialization routines, we set the state to
running before calling the host controller's start function.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The irq enabling code is going to be refactored into a new function, so
clean up some checkpatch errors before moving it.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

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: NAlan Stern <stern@rowland.harvard.edu>
Tested-by: NAlex Terekhov <a.terekhov@gmail.com>
CC: <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

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: NRobert Morell <rmorell@nvidia.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

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: NRobert Morell <rmorell@nvidia.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The USB core keeps track of pending resume requests for root hubs, in
order to resolve races between wakeup requests and suspends.  However
the code that does this is subject to another race (between wakeup
requests and resumes) because the WAKEUP_PENDING flag is cleared
before the resume occurs, leaving a window in which another wakeup
request might arrive.

This patch (as1447) fixes the problem by clearing the WAKEUP_PENDING
flag after the resume instead of before it.

This fixes Bugzilla #24952.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Tested-by: NPaul Bender <pebender@san.rr.com>
Tested-by: Nwarpme <warpme@o2.pl>
Cc: stable <stable@kernel.org> [.36+]
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The Inventra DMA engine used with the MUSB controller in many
SoCs cannot use DMA for control transfers on EP0, but can use
DMA for all other transfers.

The USB core maps urbs for DMA if hcd->self.uses_dma is true.
(hcd->self.uses_dma is true for MUSB as well).

Split the uses_dma flag into two - one that says if the
controller needs to use PIO for control transfers, and
another which says if the controller uses DMA (for all
other transfers).

Also, populate this flag for all MUSB by default.

(Tested on OMAP3 and OMAP4 boards, with EHCI and MUSB HCDs
simultaneously in use).
Signed-off-by: NMaulik Mankad <x0082077@ti.com>
Signed-off-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NAnand Gadiyar <gadiyar@ti.com>
Cc: Oliver Neukum <oliver@neukum.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Praveena NADAHALLY <praveen.nadahally@stericsson.com>
Cc: Ajay Kumar Gupta <ajay.gupta@ti.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Since the runtime-PM core already defines a .last_busy field in
device.power, this patch uses it to replace the .last_busy field
defined in usb_device and uses pm_runtime_mark_last_busy to implement
usb_mark_last_busy.
Signed-off-by: NMing Lei <tom.leiming@gmail.com>
Reviewed-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

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: NMartin Fuzzey <mfuzzey@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

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: NMaulik Mankad <x0082077@ti.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Enable MSI/MSI-X supporting in xhci driver.

Provide the mechanism to fall back using MSI and Legacy IRQs
if MSI-X IRQs register failed.
Signed-off-by: NDong Nguyen <Dong.Nguyen@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>,
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

If we use the HCD_LOCAL_MEM flag and dma_declare_coherent_memory() to
enforce the host controller's local memory utilization we also need to
disable native scatter-gather support, otherwise hcd_alloc_coherent() in
map_urb_for_dma() is called with urb->transfer_buffer == NULL, that
triggers a NULL pointer dereference.

We can also consider to add a WARN_ON() and return an error code to
better catch this problem in the future.

At the moment no driver seems to hit this bug, so I should
consider this a low-priority fix.
Signed-off-by: NAndrea Righi <arighi@develer.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

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: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

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: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1390) fixes a problem that crops up when a UHCI host
controller is unbound from uhci-hcd while there are still some active
URBs.  The URBs have to be unlinked when the root hub is unregistered,
and uhci-hcd relies upon root-hub status polls as part of its
unlinking procedure.  But usb_hcd_poll_rh_status() won't make those
status calls if hcd->rh_registered is clear, and the flag is cleared
_before_ the unregistration takes place.

Since hcd->rh_registered is used for other things and needs to be
cleared early, the solution is to add a new flag (rh_pollable) and use
it instead.  It gets cleared _after_ the root hub is unregistered.

Now that the status polls don't end too soon, we have to make sure
they also don't occur too late -- after the root hub's usb_device
structure or the HCD's private structures are deallocated.  Therefore
the patch adds usb_get_device() and usb_put_device() calls to protect
the root hub structure, and it adds an extra del_timer_sync() to
prevent the root-hub timer from causing an unexpected status poll.

This additional complexity would not be needed if the HCD framework
had provided separate stop() and release() callbacks instead of just
stop().  This lack could be fixed at some future time (although it
would require changes to every host controller driver); when that
happens this patch won't be needed any more.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch (as1389) fixes some errors in the failure pathway of
usb_add_hcd().  The actions it takes ought to be exactly the same as
those taken by usb_remove_hcd(), but they aren't.

In one case (removal of the usb_bus_attr_group), the two routines are
brought into agreement by changing usb_remove_hcd().  All the other
discrepancies are fixed by changing usb_add_hcd().
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Obviously, {} is needed in the branch of
	"else if (hcd->driver->flags & HCD_LOCAL_MEM)"
for handling of setup packet mapping.
Signed-off-by: NMing Lei <tom.leiming@gmail.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Change the type of the URB's 'sg' pointer from a usb_sg_request to
a scatterlist.  This allows drivers to submit scatter-gather lists
without using the usb_sg_wait() interface.  It has the added benefit
of removing the typecasts that were added as part of patch as1368 (and
slightly decreasing the number of pointer dereferences).
Signed-off-by: NMatthew Wilcox <willy@linux.intel.com>
Reviewed-by: NAlan Stern <stern@rowland.harvard.edu>
Tested-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>