When a scatter-gather list is enqueued to the xHCI driver, it translates
each entry into a transfer request block (TRB).  Only 63 TRBs can be
used per ring segment, and there must be one additional TRB reserved to
make sure the hardware does not think the ring is empty (so the enqueue
pointer doesn't equal the dequeue pointer).  Limit the bus sg_tablesize
to 62 TRBs.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Add a new host controller driver method, reset_device(), that the USB core
will use to notify the host of a successful device reset.  The call may
fail due to out-of-memory errors; attempt the port reset sequence again if
that happens.  Update hub_port_init() to allow resetting a configured
device.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The WHCI HCD will also support urbs with scatter-gather lists.  Add a
usb_bus field to indicated how many sg list elements are supported by
the HCD.  Use this to decide whether to pass the scatter-list to the HCD
or not.

Make the usb-storage driver use this new field.
Signed-off-by: NDavid Vrabel <david.vrabel@csr.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Add a hook for updating xHCI internal structures after khubd fetches the
hub descriptor and sets up the hub's TT information.  The xHCI driver must
update the internal structures before devices under the hub can be
enumerated.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

For a USB hub to work under an xHCI host controller, the xHC's internal
scheduler must be made aware of the hub's characteristics.  Add an xHCI
hook that the USB core will call after it fetches the hub descriptor.
This hook will add hub information to the slot context for that device,
including whether it has multiple TTs or a single TT, the number of ports
on the hub, and TT think time.

Setting up the slot context for the device is different for 0.95 and 0.96
xHCI host controllers.

Some of the slot context reserved fields in the 0.95 specification were
changed into hub fields in the 0.96 specification.  Don't set the TT think
time or number of ports for a hub if we're dealing with a 0.95-compliant
xHCI host controller.

The 0.95 xHCI specification says that to modify the hub flag, we need to
issue an evaluate context command.  The 0.96 specification says that flag
can be set with a configure endpoint command.  Issue the correct command
based on the version reported by the hardware.

This patch does not add support for multi-TT hubs.  Multi-TT hubs expose
a single TT on alt setting 0, and multi-TT on alt setting 1.  The xHCI
driver can't handle setting alternate interfaces yet.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This Fresco Logic xHCI host controller chip revision puts bad data into
the output endpoint context after a Reset Endpoint command.  It needs a
Configure Endpoint command (instead of a Set TR Dequeue Pointer command)
after the reset endpoint command.

Set up the input context before issuing the Reset Endpoint command so we
don't copy bad data from the output endpoint context.  The HW also can't
handle two commands queued at once, so submit the TRB for the Configure
Endpoint command in the event handler for the Reset Endpoint command.

Devices that stall on control endpoints before a configuration is selected
will not work under this Fresco Logic xHCI host controller revision.

This patch is for prototype hardware that will be given to other companies
for evaluation purposes only, and should not reach consumer hands.  Fresco
Logic's next chip rev should have this bug fixed.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable <stable@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

When an endpoint on a device under an xHCI host controller stalls, the
host controller driver must let the hardware know that the USB core has
successfully cleared the halt condition.  The HCD submits a Reset Endpoint
Command, which will clear the toggle bit for USB 2.0 devices, and set the
sequence number to zero for USB 3.0 devices.

The xHCI urb_enqueue will accept new URBs while the endpoint is halted,
and will queue them to the hardware rings.  However, the endpoint doorbell
will not be rung until the Reset Endpoint Command completes.

Don't queue a reset endpoint command for root hubs.  khubd clears halt
conditions on the roothub during the initialization process, but the roothub
isn't a real device, so the xHCI host controller doesn't need to know about the
cleared halt.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Since the xHCI host controller hardware (xHC) has an internal schedule, it
needs a better representation of what devices are consuming bandwidth on
the bus.  Each device is represented by a device context, with data about
the device, endpoints, and pointers to each endpoint ring.

We need to update the endpoint information for a device context before a
new configuration or alternate interface setting is selected.  We setup an
input device context with modified endpoint information and newly
allocated endpoint rings, and then submit a Configure Endpoint Command to
the hardware.

The host controller can reject the new configuration if it exceeds the bus
bandwidth, or the host controller doesn't have enough internal resources
for the configuration.  If the command fails, we still have the older
device context with the previous configuration.  If the command succeeds,
we free the old endpoint rings.

The root hub isn't a real device, so always say yes to any bandwidth
changes for it.

The USB core will enable, disable, and then enable endpoint 0 several
times during the initialization sequence.  The device will always have an
endpoint ring for endpoint 0 and bandwidth allocated for that, unless the
device is disconnected or gets a SetAddress 0 request.  So we don't pay
attention for when xhci_check_bandwidth() is called for a re-add of
endpoint 0.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Allow device drivers to enqueue URBs to control endpoints on devices under
an xHCI host controller.  Each control transfer is represented by a
series of Transfer Descriptors (TDs) written to an endpoint ring.  There
is one TD for the Setup phase, (optionally) one TD for the Data phase, and
one TD for the Status phase.

Enqueue these TDs onto the endpoint ring that represents the control
endpoint.  The host controller hardware will return an event on the event
ring that points to the (DMA) address of one of the TDs on the endpoint
ring.  If the transfer was successful, the transfer event TRB will have a
completion code of success, and it will point to the Status phase TD.
Anything else is considered an error.

This should work for control endpoints besides the default endpoint, but
that hasn't been tested.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

xHCI needs to get a "Slot ID" from the host controller and allocate other
data structures for every USB device.  Make usb_alloc_dev() and
usb_release_dev() allocate and free these device structures.  After
setting up the xHC device structures, usb_alloc_dev() must wait for the
hardware to respond to an Enable Slot command.  usb_alloc_dev() fires off
a Disable Slot command and does not wait for it to complete.

When the USB core wants to choose an address for the device, the xHCI
driver must issue a Set Address command and wait for an event for that
command.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Add functionality for getting port status and hub descriptor for xHCI root
hubs.  This is WIP because the USB 3.0 hub descriptor is different from
the USB 2.0 hub descriptor.  For now, we lie about the root hub descriptor
because the changes won't effect how the core talks to the root hub.
Later we will need to add the USB 3.0 hub descriptor for real hubs, and
this code might change.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

xHCI host controllers can optionally implement a no-op test.  This
simple test ensures the OS has correctly setup all basic data structures
and can correctly respond to interrupts from the host controller
hardware.

There are two rings exercised by the no-op test:  the command ring, and
the event ring.

The host controller driver writes a no-op command TRB to the command
ring, and rings the doorbell for the command ring (the first entry in
the doorbell array).  The hardware receives this event, places a command
completion event on the event ring, and fires an interrupt.

The host controller driver sees the interrupt, and checks the event ring
for TRBs it can process, and sees the command completion event.  (See
the rules in xhci-ring.c for who "owns" a TRB.  This is a simplified set
of rules, and may not contain all the details that are in the xHCI 0.95
spec.)

A timer fires every 60 seconds to debug the state of the hardware and
command and event rings.  This timer only runs if
CONFIG_USB_XHCI_HCD_DEBUGGING is 'y'.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Add PCI initialization code to take control of the xHCI host controller
away from the BIOS, halt, and reset the host controller.  The xHCI spec
says that BIOSes must give up the host controller within 5 seconds.

Add some host controller glue functions to handle hardware initialization
and memory allocation for the host controller.  The current xHCI
prototypes use PCI interrupts, but the xHCI spec requires MSI-X
interrupts.  Add code to support MSI-X interrupts, but use the PCI
interrupts for now.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>