Since the struct hc_driver is mostly the same across the xhci-pci,
xhci-plat, and the upcoming xhci-tegra driver, introduce the function
xhci_init_driver() which will populate the hc_driver with the default
xHCI operations.  The caller must supply a setup function which will
be used as the hc_driver's reset callback.

Note that xhci-plat also overrides the default ->start() callback so
that it can do rcar-specific initialization.
Signed-off-by: NAndrew Bresticker <abrestic@chromium.org>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

USB hub has started to use a workqueue instead of kthread. Let's update
the documentation and comments here and there.

This patch mostly just replaces "khubd" with "hub_wq". There are only few
exceptions where the whole sentence was updated. These more complicated
changes can be found in the following files:

	   Documentation/usb/hotplug.txt
	   drivers/net/usb/usbnet.c
	   drivers/usb/core/hcd.c
	   drivers/usb/host/ohci-hcd.c
	   drivers/usb/host/xhci.c
Signed-off-by: NPetr Mladek <pmladek@suse.cz>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

V2 - Restart polling (which will restart the timer) for the shared
HCD in xhci_resume().

xhci_suspend() will stop the primary HCD's root hub timer, but leaves
the shared HCD's timer running. This change adds stopping of the
shared HCD timer.
Signed-off-by: NAl Cooper <alcooperx@gmail.com>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There are multiple reasons for this:

1) This fixes a missing check for xhci_alloc_command failing in
   xhci_handle_cmd_stop_ep()
2) This adds a warning when we cannot set the new dequeue state because of
   xhci_alloc_command failing
3) It puts the allocation of the command after the sanity checks in
   queue_set_tr_deq(), avoiding leaking the command if those fail
4) Since queue_set_tr_deq now owns the command it can free it if queue_command
   fails
5) It reduces code duplication
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Resuming from hibernate (S4) will restart and re-initialize xHC.
The device contexts are freed and will be re-allocated later during device reset.

Usb core will disable link pm in device resume before device reset, which will
try to change the max exit latency, accessing the device contexts before they are re-allocated.

There is no need to zero (disable) the max exit latency when disabling hw lpm
for a freshly re-initialized xHC. So check that device context exists before
doing anything. The max exit latency will be set again after device reset when usb core
enables the link pm.
Reported-by: NImre Deak <imre.deak@intel.com>
Tested-by: NImre Deak <imre.deak@intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When we manually need to move the TR dequeue pointer we need to set the
correct cycle bit as well. Previously we used the trb pointer from the
last event received as a base, but this was changed in
commit 1f81b6d2 ("usb: xhci: Prefer endpoint context dequeue pointer")
to use the dequeue pointer from the endpoint context instead

It turns out some Asmedia controllers advance the dequeue pointer
stored in the endpoint context past the event triggering TRB, and
this messed up the way the cycle bit was calculated.

Instead of adding a quirk or complicating the already hard to follow cycle bit
code, the whole cycle bit calculation is now simplified and adapted to handle
event and endpoint context dequeue pointer differences.

Fixes: 1f81b6d2 ("usb: xhci: Prefer endpoint context dequeue pointer")
Reported-by: NMaciej Puzio <mx34567@gmail.com>
Reported-by: NEvan Langlois <uudruid74@gmail.com>
Reviewed-by: NJulius Werner <jwerner@chromium.org>
Tested-by: NMaciej Puzio <mx34567@gmail.com>
Tested-by: NEvan Langlois <uudruid74@gmail.com>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Streams on the EJ168 do not work as they should. I've spend 2 days trying
to get them to work, but without success.

The first problem is that when ever you ring the stream-ring doorbell, the
controller starts executing trbs at the beginning of the first ring segment,
event if it ended somewhere else previously. This can be worked around by
allowing enqueing only one td (not a problem with how streams are typically
used) and then resetting our copies of the enqueueing en dequeueing pointers
on a td completion to match what the controller seems to be doing.

This way things seem to start working with uas and instead of being able
to complete only the very first scsi command, the scsi core can probe the disk.

But then things break later on when td-s get enqueued with more then one
trb. The controller does seem to increase its dequeue pointer while executing
a stream-ring (data transfer events I inserted for debugging do trigger).
However execution seems to stop at the final normal trb of a multi trb td,
even if there is a data transfer event inserted after the final trb.

The first problem alone is a serious deviation from the spec, and esp.
dealing with cancellation would have been very tricky if not outright
impossible, but the second problem simply is a deal breaker altogether,
so this patch simply disables streams.

Note this will cause the usb-storage + uas driver pair to automatically switch
to using usb-storage instead of uas on these devices, essentially reverting
to the 3.14 and earlier behavior when uas was marked CONFIG_BROKEN.

https://bugzilla.redhat.com/show_bug.cgi?id=1121288
https://bugzilla.kernel.org/show_bug.cgi?id=80101

Cc: stable@vger.kernel.org # 3.15
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

grep must work, not matter the line length.
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

As best case, a host controller should support U0 to U1 switching for
the devices connected below any tier of hub level supported by usb
specification. Therefore xhci_check_tier_policy should always return
success as default implementation.

A host should be able to issue LGO_Ux after the timeout calculated as
per definition of system exit latency defined in C.1.5.2. Therefore
xhci_calculate_ux_timeout returns ux_params.sel as the default
implementation.

Use default calculation in absence of any vendor specific limitations.
Signed-off-by: NPratyush Anand <pratyush.anand@st.com>
Tested-by: NAymen Bouattay <aymen.bouattay@st.com>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The current XHCI driver recalculates the Context Entries field in the
Slot Context on every add_endpoint() and drop_endpoint() call. In the
case of drop_endpoint(), it seems to assume that the add_flags will
always contain every endpoint for the new configuration, which is not
necessarily correct if you don't make assumptions about how the USB core
uses the add_endpoint/drop_endpoint interface (add_flags only contains
endpoints that are new additions in the new configuration).

Furthermore, EP0_FLAG is not consistently set in add_flags throughout
the lifetime of a device. This means that when all endpoints are
dropped, the Context Entries field can be set to 0 (which is invalid and
may cause a Parameter Error) or -1 (which is interpreted as 31 and
causes the driver to keep using the old, incorrect value).

The only surefire way to set this field right is to also take all
existing endpoints into account, and to force the value to 1 (meaning
only EP0 is active) if no other endpoint is found. This patch implements
that as a single step in the final check_bandwidth() call and removes
the intermediary calculations from add_endpoint() and drop_endpoint().
Signed-off-by: NJulius Werner <jwerner@chromium.org>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The system suspend flow as following:
1, Freeze all user processes and kenrel threads.

2, Try to suspend all devices.

2.1, If pci device is in RPM suspended state, then pci driver will try
to resume it to RPM active state in the prepare stage.

2.2, xhci_resume function calls usb_hcd_resume_root_hub to queue two
workqueue items to resume usb2&usb3 roothub devices.

2.3, Call suspend callbacks of devices.

2.3.1, All suspend callbacks of all hcd's children, including
roothub devices are called.

2.3.2, Finally, hcd_pci_suspend callback is called.

Due to workqueue threads were already frozen in step 1, the workqueue
items can't be scheduled, and the roothub devices can't be resumed in
this flow. The HCD_FLAG_WAKEUP_PENDING flag which is set in
usb_hcd_resume_root_hub won't be cleared. Finally,
hcd_pci_suspend will return -EBUSY, and system suspend fails.

The reason why this issue doesn't show up very often is due to that
choose_wakeup will be called in step 2.3.1. In step 2.3.1, if
udev->do_remote_wakeup is not equal to device_may_wakeup(&udev->dev), then
udev will resume to RPM active for changing the wakeup settings. This
has been a lucky hit which hides this issue.

For some special xHCI controllers which have no USB2 port, then roothub
will not match hub driver due to probe failed. Then its
do_remote_wakeup will be set to zero, and we won't be as lucky.

xhci driver doesn't need to resume roothub devices everytime like in
the above case. It's only needed when there are pending event TRBs.

This patch should be back-ported to kernels as old as 3.2, that
contains the commit f69e3120
"USB: XHCI: resume root hubs when the controller resumes"

Cc: stable@vger.kernel.org # 3.2
Signed-off-by: NWang, Yu <yu.y.wang@intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
[use readl() instead of removed xhci_readl(), reword commit message -Mathias]
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Use one timer to control command timeout.

start/kick the timer every time a command is completed and a
new command is waiting, or a new command is added to a empty list.

If the timer runs out, then tag the current command as "aborted", and
start the xhci command abortion process.

Previously each function that submitted a command had its own timer.
If that command timed out, a new command structure for the
command was created and it was put on a cancel_cmd_list list,
then a pci write to abort the command ring was issued.

when the ring was aborted, it checked if the current command
was the one to be canceled, later when the ring was stopped the
driver got ownership of the TRBs in the command ring,
compared then to the TRBs in the cancel_cmd_list,
and turned them into No-ops.

Now, instead, at timeout we tag the status of the command in the
command queue to be aborted, and start the ring abortion.
Ring abortion stops the command ring and gives control of the
commands to us.
All the aborted commands are now turned into No-ops.

If the ring is already stopped when the command times outs its not possible
to start the ring abortion, in this case the command is turnd to No-op
right away.

All these changes allows us to remove the entire cancel_cmd_list code.

The functions waiting for a command to finish no longer have their own timeouts.
They will wait either until the command completes normally,
or until the whole command abortion is done.
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Remove the per-device command list and handle_cmd_in_cmd_wait_list()
and use the completion and status variables found in the
command structure in the global command list.
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Create a list to store command structures, add a structure to it every time
a command is submitted, and remove it from the list once we get a
command completion event matching the command.

Callers that wait for completion will free their command structures themselves.
The other command structures are freed in the command completion event handler.

Also add a check that prevents queuing commands if host is dying
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

To create a global command queue we require that each command put on the
command ring is submitted with a command structure.

Functions that queue commands and wait for completion need to allocate a command
before submitting it, and free it once completed. The following command queuing
functions need to be modified.

xhci_configure_endpoint()
xhci_address_device()
xhci_queue_slot_control()
xhci_queue_stop_endpoint()
xhci_queue_new_dequeue_state()
xhci_queue_reset_ep()
xhci_configure_endpoint()

xhci_configure_endpoint() could already be called with a command structure,
and only xhci_check_maxpacket and xhci_check_bandwidth did not do so. These
are changed and a command structure is now required. This change also simplifies
the configure endpoint command completion handling and the "goto bandwidth_change"
handling code can be removed.

In some cases the command queuing function is called in interrupt context.
These commands needs to be allocated atomically, and they can't wait for
completion. These commands will in this patch be freed directly after queuing,
but freeing will be moved to the command completion event handler in a later
patch once we get the global command queue up.(Just so that we won't leak
memory in the middle of the patch set)
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

xHCI host controllers may only support a limited number of device slot
IDs, which is usually far less than the theoretical maximum number of
devices (255) that the USB specifications advertise.  This is
frustrating to consumers that expect to be able to plug in a large
number of devices.

Add a print statement when the Enable Slot command fails to show how
many devices the host supports.  We can't change hardware manufacturer's
design decisions, but hopefully we can save customers a little bit of
time trying to debug why their host mysteriously fails when too many
devices are plugged in.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: NAmund Hov <Amund.Hov@silabs.com>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

As result of deprecation of MSI-X/MSI enablement functions
pci_enable_msix() and pci_enable_msi_block() all drivers
using these two interfaces need to be updated to use the
new pci_enable_msi_range()  or pci_enable_msi_exact()
and pci_enable_msix_range() or pci_enable_msix_exact()
interfaces.
Signed-off-by: NAlexander Gordeev <agordeev@redhat.com>
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch fix wrong port number reported when trying to enable/disable
USB2.0 hardware LPM.
Signed-off-by: NLin Wang <lin.x.wang@intel.com>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When CONFIG_PCI and CONFIG_PM are not selected, xhci.c gets this
warning:
drivers/usb/host/xhci.c:409:13: warning: ‘xhci_msix_sync_irqs’ defined
but not used [-Wunused-function]

Instead of creating nested #ifdefs, this patch fixes it by defining the
xHCI PCI stubs as inline.

This warning has been in since 3.2 kernel and was
caused by commit 421aa841
"usb/xhci: hide MSI code behind PCI bars", but wasn't noticed
until 3.13 when a configuration with these options was tried
Signed-off-by: NDavid Cohen <david.a.cohen@linux.intel.com>
Cc: stable@vger.kernel.org # 3.2
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We have observed a rare cycle state desync bug after Set TR Dequeue
Pointer commands on Intel LynxPoint xHCs (resulting in an endpoint that
doesn't fetch new TRBs and thus an unresponsive USB device). It always
triggers when a previous Set TR Dequeue Pointer command has set the
pointer to the final Link TRB of a segment, and then another URB gets
enqueued and cancelled again before it can be completed. Further
investigation showed that the xHC had returned the Link TRB in the TRB
Pointer field of the Transfer Event (CC == Stopped -- Length Invalid),
but when xhci_find_new_dequeue_state() later accesses the Endpoint
Context's TR Dequeue Pointer field it is set to the first TRB of the
next segment.

The driver expects those two values to be the same in this situation,
and uses the cycle state of the latter together with the address of the
former. This should be fine according to the XHCI specification, since
the endpoint ring should be stopped when returning the Transfer Event
and thus should not advance over the Link TRB before it gets restarted.
However, real-world XHCI implementations apparently don't really care
that much about these details, so the driver should follow a more
defensive approach to try to work around HC spec violations.

This patch removes the stopped_trb variable that had been used to store
the TRB Pointer from the last Transfer Event of a stopped TRB. Instead,
xhci_find_new_dequeue_state() now relies only on the Endpoint Context,
requiring a small amount of additional processing to find the virtual
address corresponding to the TR Dequeue Pointer. Some other parts of the
function were slightly rearranged to better fit into this model.

This patch should be backported to kernels as old as 2.6.31 that contain
the commit ae636747 "USB: xhci: URB
cancellation support."
Signed-off-by: NJulius Werner <jwerner@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 247bf557.

This commit, together with commit 3804fad4
"USBNET: ax88179_178a: enable tso if usb host supports sg dma" were
origially added to get xHCI 1.0 hosts and usb ethernet ax88179_178a devices
working together with scatter gather. xHCI 1.0 hosts pose some requirement on how transfer
buffers are aligned, setting this requirement for 1.0 hosts caused USB 3.0 mass
storage devices to fail more frequently.

USB 3.0 mass storage devices used to work before 3.14-rc1.  Theoretically,
the TD fragment rules could have caused an occasional disk glitch.
Now the devices *will* fail, instead of theoretically failing.
>From a user perspective, this looks like a regression; the USB device obviously
fails on 3.14-rc1, and may sometimes silently fail on prior kernels.

The proper soluition is to implement the TD fragment rules required, but for now
this patch needs to be reverted to get USB 3.0 mass storage devices working at the
level they used to.
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When some xHCI host controllers fall back to use the legacy IRQ,
the member irq_descr of the usb_hcd structure will be empty. This
leads to the empty string of the xHCI host controller in
/proc/interrupts. Here is the example (The irq 19 is the xHCI host
controller):

           CPU0
  0:         91		IO-APIC-edge      	timer
  8:          1         IO-APIC-edge      	rtc0
  9:       7191         IO-APIC-fasteoi   	acpi
 18:        104       	IR-IO-APIC-fasteoi 	ehci_hcd:usb1, ehci_hcd:usb2
 19:        473     	IR-IO-APIC-fasteoi

After applying the patch, the name of the registered xHCI host
controller can be displayed correctly. Here is the example:

           CPU0
  0:         91		IO-APIC-edge      	timer
  8:          1         IO-APIC-edge      	rtc0
  9:       7191         IO-APIC-fasteoi   	acpi
 18:        104       	IR-IO-APIC-fasteoi 	ehci_hcd:usb1, ehci_hcd:usb2
 19:        473     	IR-IO-APIC-fasteoi	xhci_hcd:usb3

Tested on v3.14-rc4.
Signed-off-by: NAdrian Huang <ahuang12@lenovo.com>
Reviewed-by: NNagananda Chumbalkar <nchumbalkar@lenovo.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The ss_ep_comp bmAttributes filed can contain more info then just the
streams, use usb_ss_max_streams to properly get max streams.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

And warn about this, as that would be a driver bug.

Like wise drivers should ensure that streams are properly free-ed before a
device is reset. So lets warn about that too. This already causes warnings
in the form of:

[   96.982398] xhci_hcd 0000:01:00.0: WARN Can't disable streams for endpoint 0x81
, streams are already disabled!
[   96.982400] xhci_hcd 0000:01:00.0: WARN xhci_free_streams() called with non-streams endpoint

But it is better to also warn about the actual cause of this later warnings.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

This reverts commit f2d9b991.

We are ripping out commit 35773dac "usb:
xhci: Link TRB must not occur within a USB payload burst" because it's a
hack that caused regressions in the usb-storage and userspace USB
drivers that use usbfs and libusb.  This commit attempted to fix the
issues with that patch.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org #3.12

xHCI 1.0 hosts have a set of requirements on how to align transfer
buffers on the endpoint rings called "TD fragment" rules.  When the
ax88179_178a driver added support for scatter gather in 3.12, with
commit 804fad45411b48233b48003e33a78f290d227c8 "USBNET: ax88179_178a:
enable tso if usb host supports sg dma", it broke the device under xHCI
1.0 hosts.  Under certain network loads, the device would see an
unexpected short packet from the host, which would cause the device to
stop sending ethernet packets, even through USB packets would still be
sent.

Commit 35773dac "usb: xhci: Link TRB must not occur within a USB
payload burst" attempted to fix this.  It was a quick hack to partially
implement the TD fragment rules.  However, it caused regressions in the
usb-storage layer and userspace USB drivers using libusb.  The patches
to attempt to fix this are too far reaching into the USB core, and we
really need to implement the TD fragment rules correctly in the xHCI
driver, instead of continuing to wallpaper over the issues.

Disable arbitrarily-aligned scatter-gather in the xHCI driver for 1.0
hosts.  Only the ax88179_178a driver checks the no_sg_constraint flag,
so don't set it for 1.0 hosts.  This should not impact usb-storage or
usbfs behavior, since they pass down max packet sized aligned sg-list
entries (512 for USB 2.0 and 1024 for USB 3.0).
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: NMark Lord <mlord@pobox.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Bjørn Mork <bjorn@mork.no>
Cc: Freddy Xin <freddy@asix.com.tw>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: stable@vger.kernel.org # 3.12

This reverts commit e8b37332.  Many xHCI
host controllers can only handle 32-bit addresses, and writing 64-bits
at a time causes them to fail.  Reading 64-bits at a time may also cause
them to return 0xffffffff, so revert this commit as well.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

This reverts commit 7dd09a1a.

Many xHCI host controllers can only handle 32-bit addresses, and writing
64-bits at a time causes them to fail.  Rafał reports that USB devices
simply do not enumerate, and reverting this patch helps.  Branimir
reports that his host controller doesn't respond to an Enable Slot
command and dies:

[   75.576160] xhci_hcd 0000:03:00.0: Timeout while waiting for a slot
[   88.991634] xhci_hcd 0000:03:00.0: Stopped the command ring failed, maybe the host is dead
[   88.991748] xhci_hcd 0000:03:00.0: Abort command ring failed
[   88.991845] xhci_hcd 0000:03:00.0: HC died; cleaning up
[   93.985489] xhci_hcd 0000:03:00.0: Timeout while waiting for a slot
[   93.985494] xhci_hcd 0000:03:00.0: Abort the command ring, but the xHCI is dead.
[   98.982586] xhci_hcd 0000:03:00.0: Timeout while waiting for a slot
[   98.982591] xhci_hcd 0000:03:00.0: Abort the command ring, but the xHCI is dead.
[  103.979696] xhci_hcd 0000:03:00.0: Timeout while waiting for a slot
[  103.979702] xhci_hcd 0000:03:00.0: Abort the command ring, but the xHCI is dead
Signed-off-by: NSarah Sharp <sarah.a.sharp@intel.com>
Reported-by: NRafał Miłecki <zajec5@gmail.com>
Reported-by: NBranimir Maksimovic <branimir.maksimovic@gmail.com>
Cc: Xenia Ragiadakou <burzalodowa@gmail.com>

Commit 35773dac "usb: xhci: Link TRB
must not occur within a USB payload burst" attempted to fix an issue
found with USB ethernet adapters, and inadvertently broke USB storage
devices.  The patch attempts to ensure that transfers never span a
segment, and rejects transfers that have more than 63 entries (or
possibly less, if some entries cross 64KB boundaries).

usb-storage limits the maximum transfer size to 120K, and we had assumed
the block layer would pass a scatter-gather list of 4K entries,
resulting in no more than 31 sglist entries:

http://marc.info/?l=linux-usb&m=138498190419312&w=2

That assumption was wrong, since we've seen the driver reject a write
that was 218 sectors long (of probably 512 bytes each):

Jan  1 07:04:49 jidanni5 kernel: [  559.624704] xhci_hcd 0000:00:14.0: Too many fragments 79, max 63
...
Jan  1 07:04:58 jidanni5 kernel: [  568.622583] Write(10): 2a 00 00 06 85 0e 00 00 da 00

Limit the number of scatter-gather entries to half a ring segment.  That
should be margin enough in case some entries cross 64KB boundaries.
Increase the number of TRBs per segment from 64 to 256, which should
result in ring segments fitting on a 4K page.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: jidanni@jidanni.org
References: http://bugs.debian.org/733907
Fixes: 35773dac ('usb: xhci: Link TRB must not occur within a USB payload burst')
Cc: stable <stable@vger.kernel.org> # 3.12

If CONFIG_PCI is enabled, make sure xhci_cleanup_msix()
doesn't try to free a bogus PCI IRQ or dereference an invalid
pci_dev when the xHCI device is actually a platform_device.

This patch should be backported to kernels as old as 3.9, that
contain the commit 52fb6125
"xhci-plat: Don't enable legacy PCI interrupts."
Signed-off-by: NJack Pham <jackp@codeaurora.org>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org

It makes easier for debugging some hardware specific issues.

Note that this option won't override the value to be set.  That is,
you can turn quirks on by this option but cannot turn them off if set
by the driver.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Specify whether we are only performing the context setup portion of the
'address device' command, or the full operation issuing 'SetAddress'
on the wire.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Change the default enumeration scheme for xhci attached non-SuperSpeed
devices from:

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

...to:

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

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

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

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

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

instead of:

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

which results in the discovery process looping until falling back to
'old scheme' enumeration.
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Reported-by: NDavid Moore <david.moore@gmail.com>
Suggested-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Function xhci_write_64() is used to write 64bit xHC registers residing in MMIO.
On 32bit systems, xHC registers need to be written with 32bit accesses by
writing first the lower 32bits and then the higher 32bits. The header file
asm-generic/io-64-nonatomic-lo-hi.h ensures that on 32bit systems writeq() will
will write 64bit registers in 32bit chunks with low-high order.

Replace all calls to xhci_write_64() with calls to writeq().

This is done to reduce code duplication since 64bit low-high write logic
is already implemented and to take advantage of inherent "atomic" 64bit
write operations on 64bit systems.
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Function xhci_read_64() is used to read 64bit xHC registers residing in MMIO.
On 32bit systems, xHC registers need to be read with 32bit accesses by
reading first the lower 32bits and then the higher 32bits.

Replace all calls to xhci_read_64() with calls to readq() and include
asm-generic/io-64-nonatomic-lo-hi.h header file, so that if the system
is not 64bit, readq() will read registers in 32bit chunks with low-high order.

This is done to reduce code duplication since 64bit low-high read logic
is already implemented and to take advantage of inherent "atomic" 64bit
read operations on 64bit systems.
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Function xhci_writel() is used to write a 32bit value in xHC registers residing
in MMIO address space. It takes as first argument a pointer to the xhci_hcd
although it does not use it. xhci_writel() internally simply calls writel().
This creates an illusion that xhci_writel() is an xhci specific function that
has to be called in a context where a pointer to xhci_hcd is available.

Remove xhci_writel() wrapper function and replace its calls with calls to
writel() to make the code more straight-forward.
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Function xhci_readl() is used to read 32bit xHC registers residing in MMIO
address space. It takes as first argument a pointer to the xhci_hcd although
it does not use it. xhci_readl() internally simply calls readl(). This creates
an illusion that xhci_readl() is an xhci specific function that has to be
called in a context where a pointer to xhci_hcd is available.

Remove the unnecessary xhci_readl() wrapper function and replace its calls to
with calls to readl() to make the code more straightforward.
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The fields 'add_flags' and 'drop_flags' in struct xhci_input_control_ctx
have type __le32 and need to be converted to CPU byteorder before being
used to derive the number of dropped endpoints.
This bug was found using sparse.

This patch is not suitable for stable, since the bug would only be
triggered on big endian systems, and the code only runs for Intel xHCI
host controllers, which are always integrated into little endian
systems.
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>