Section 4.11.7.1 of rev 1.0 of the xhci specification states that a link TRB
can only occur at a boundary between underlying USB frames (512 bytes for
high speed devices).

If this isn't done the USB frames aren't formatted correctly and, for example,
the USB3 ethernet ax88179_178a card will stop sending (while still receiving)
when running a netperf tcp transmit test with (say) and 8k buffer.

This should be a candidate for stable, the ax88179_178a driver defaults to
gso and tso enabled so it passes a lot of fragmented skb to the USB stack.

Notes from Sarah:

Discussion: http://marc.info/?l=linux-usb&m=138384509604981&w=2

This patch fixes a long-standing xHCI driver bug that was revealed by a
change in 3.12 in the usb-net driver.  Commit
638c5115 "USBNET: support DMA SG" added
support to use bulk endpoint scatter-gather (urb->sg).  Only the USB
ethernet drivers trigger this bug, because the mass storage driver sends
sg list entries in page-sized chunks.

This patch only fixes the issue for bulk endpoint scatter-gather.  The
problem will still occur for periodic endpoints, because hosts will
interpret no-op transfers as a request to skip a service interval, which
is not what we want.

Luckily, the USB core isn't set up for scatter-gather on isochronous
endpoints, and no USB drivers use scatter-gather for interrupt
endpoints.  Document this known limitation so that developers won't try
to use urb->sg for interrupt endpoints until this issue is fixed.  The
more comprehensive fix would be to allow link TRBs in the middle of the
endpoint ring and revert this patch, but that fix would touch too much
code to be allowed in for stable.

This patch should be backported to kernels as old as 3.12, that contain
the commit 638c5115 "USBNET: support DMA
SG".  Without this patch, the USB network device gets wedged, and stops
sending packets.  Mark Lord confirms this patch fixes the regression:

http://marc.info/?l=linux-netdev&m=138487107625966&w=2Signed-off-by: NDavid Laight <david.laight@aculab.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: NMark Lord <mlord@pobox.com>
Cc: stable@vger.kernel.org

Acked-by: NFelipe Balbi <balbi@ti.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The correct way for a driver to specify the coherent DMA mask is
not to directly access the field in the struct device, but to use
dma_set_coherent_mask().  Only arch and bus code should access this
member directly.

Convert all direct write accesses to using the correct API.
Acked-by: NFelipe Balbi <balbi@ti.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add a comment to explain why this driver doesn't call any of the DMA
API dma_set_mask() functions.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Replace the following sequence:

	dma_set_mask(dev, mask);
	dma_set_coherent_mask(dev, mask);

with a call to the new helper dma_set_mask_and_coherent().
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Replace the following sequence:

	dma_set_mask(dev, mask);
	dma_set_coherent_mask(dev, mask);

with a call to the new helper dma_set_mask_and_coherent().
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The AT91 PMC (Power Management Controller) provides a USB clock used by
the different USB controllers (ehci, ohci and udc).
The atmel-ehci driver must configure the usb clock rate to 48Mhz in order
to get a fully functionnal USB host controller.
This configuration was formely done in mach-at91/clock.c, but will be
bypassed when moving to common clk framework.

This patch adds support for usb clock retrieval and configuration only if
CCF is enabled (CONFIG_COMMON_CLK).
Signed-off-by: NBoris BREZILLON <b.brezillon@overkiz.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add a quirk for Alereon HWA devices to concatenate the frames of isoc
transfer requests.
Signed-off-by: NThomas Pugliese <thomas.pugliese@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Convert ep93xx to use the OHCI platform driver and remove the
ohci-ep93xx bus glue driver.

Enable CONFIG_OHCI_HCD_PLATFORM in the ep93xx_defconfig so that USB
is still enabled by default on the EP93xx platform.
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: Ryan Mallon <rmallon@gmail.com>
Cc: Lennert Buytenhek <kernel@wantstofly.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Olof Johansson <olof@lixom.net>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

hcd-pci.c in usbcore contains a check for wakeup requests racing with
controller suspend.  This check is going to be moved out of usbcore
and into the individual controller drivers, where it can apply to all
platforms, not just PCI.

This patch adds the check to uhci-hcd.  Ironically, none of the
non-PCI platform drivers for uhci-hcd implement suspend/resume.
Nevertheless, this change is needed to accomodate the upcoming change
to usbcore.

The patch also removes an outdated check of the root hub state.  For
one thing, the PM layer has long been quite reliable about suspending
root hubs before controllers.  For another, virtually the same check
is also made in hcd-pci.c; there's no point in repeating it.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

hcd-pci.c in usbcore contains a check for wakeup requests racing with
controller suspend.  This check is going to be moved out of usbcore
and into the individual controller drivers, where it can apply to all
platforms, not just PCI.

This patch adds the check to ehci-hcd.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch fixes an endian-related error in ohci-hcd (detected by
sparse) and clarifies a comment explaining a peculiar locking
arrangement that sparse warns about.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch fixes several sparse errors in ehci-hcd introduced by
commit 3d091a6f (USB: EHCI: AMD periodic frame list table quirk).
Although the problem fixed by that commit affects only little-endian
systems, the source code has to use types appropriate for big-endian
too.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch fixes a type mismatch in ehci-hcd caused by commit
b35c5009 (USB: EHCI: create per-TT bandwidth tables).  The c_maskp
parameter in check_intr_schedule() was changed to point to unsigned
int rather than __hc32, but the prototype declaration wasn't adjusted
accordingly.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Do not overwrite the multi-byte fields of usb_wa_descriptor with their
cpu format values after reading the descriptor.  Leave the values as
__le16 and swap on use.  This is more consistent with other uses of USB
descriptors.
Signed-off-by: NThomas Pugliese <thomas.pugliese@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Only used for debug output, so we don't need to save it.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Perform an unconditional toggle of the cycle bit with 'xor'.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

This patch replaces the 'event' argument of xhci_handle_cmd_set_deq() and
xhci_handle_cmd_reset_ep(), which is used to retrieve the command completion
status code, with the cmd_comp_code directly, since it is available.
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Acked-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Since the Slot ID field in the command completion event matches the Slot ID
field in the associated command TRB for the Stop Endpoint, Set Dequeue Pointer
and Reset Endpoint commands, this patch adds in the handlers of their
completion events a 'slot_id' argument and removes the slot id calculation
in each of them.
Also, a WARN_ON() was added in case the slot ids reported by command TRB and
event TRB differ (although according to xhci spec rev1.0 that should not happen)
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

This patch replaces 'xhci->cmd_ring->dequeue' with 'trb', the address of
the command TRB, since it is available to reduce line length.
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Acked-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

This patch adds a new variable 'cmd_type' to hold the command type so that
switch cases can be simplified by removing TRB_TYPE() macro improving
code readability.
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

This patch adds a new variable 'cmd_trb' to hold the address of the
command TRB, that is associated with the command completion event,
and to replace repetitions of xhci->cmd_ring->dequeue into the code.
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Acked-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

This patch adds a new variable 'cmd_comp_code' to hold the command completion
status code aiming to reduce code duplication and to improve code readability.
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Acked-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The function that handles xHCI command completion is much too long and
there is need to be broken up into individual functions for each command
completion to improve code readablity.
This patch refactors the code in TRB_CONFIG_EP switch case, in
handle_cmd_completion(), into a fuction named xhci_handle_cmd_config_ep().

There were added two additional variables, 'add_flags' and 'drop_flags',
to reduce line length below 80 chars and improve code readability.
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

This patch removes the variable 'ep_ring' that is assigned in
TRB_CONFIG_EP switch case but never used.
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The function that handles xHCI command completion is much too long and
there is need to be broken up into individual functions for each command
completion to improve code readablity.
This patch refactors the code in TRB_EVAL_CONTEXT switch case in
handle_cmd_completion() into a fuction named xhci_handle_cmd_eval_ctx().
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The function that handles xHCI command completion is much too long and
there is need to be broken up into individual functions for each command
completion to improve code readablity.
This patch refactors the code in TRB_NEC_GET_FW switch case in
handle_cmd_completion() into a fuction named xhci_handle_cmd_nec_get_fw().
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The function that handles xHCI command completion is much too long and
there is need to be broken up into individual functions for each command
completion to improve code readablity.
This patch refactors the code in TRB_RESET_DEV switch case in
handle_cmd_completion() into a fuction named xhci_handle_cmd_reset_dev().
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

Since the slot id retrieved from the Reset Device TRB matches the slot id in
the command completion event, which is available, there is no need to determine
it again.
This patch removes the uneccessary reassignment to slot id and adds a WARN_ON
in case the two Slot ID fields differ (although according xhci spec rev1.0
they should not differ).
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The function that handles xHCI command completion is much too long and
there is need to be broken up into individual functions for each command
completion to improve code readablity.
This patch refactors the code in TRB_ADDR_DEV switch case in
handle_cmd_completion() into a fuction named xhci_handle_cmd_addr_dev().
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The function that handles xHCI command completion is much too long and
there is need to be broken up into individual functions for each command
completion to improve code readablity.
This patch refactors the code in TRB_DISABLE_SLOT switch case in
handle_cmd_completion() into a fuction named xhci_handle_cmd_disable_slot().
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The function that handles xHCI command completion is much too long and
there is need to be broken up into individual functions for each command
completion to improve code readablity.
This patch refactors the code in TRB_ENABLE_SLOT switch case in
handle_cmd_completion() into a fuction named xhci_handle_cmd_enable_slot().
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

This patch renames the function handlers of a triggered Command Completion
Event that correspond to each command type into 'xhci_handle_cmd_<type>'.
That is done to give a consistent naming space to all the functions that
handle Command Completion Events and that will permit the code reader to
reference to them more easily.
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Acked-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

This patch removes the "adjective" argument from xhci_giveback_urb_in_irq(),
since it is not used in the function anymore.
Signed-off-by: NXenia Ragiadakou <burzalodowa@gmail.com>
Acked-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The usage of USB_CTRL_SET_TIMEOUT in xhci is incorrect.
The definition of USB_CTRL_SET_TIMEOUT is 5000ms. The
input timeout to wait_for_completion_interruptible_timeout
is jiffies. That makes the timeout be longer than what
we want, such as 50s in some platform.

The patch is to use XHCI_CMD_DEFAULT_TIMEOUT instead of
USB_CTRL_SET_TIMEOUT as command completion event timeout.
Signed-off-by: Nxiao jin <jin.xiao@intel.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

'xhci_del_comp_mod_timer' is local to this file.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The USB core currently handles enabling and disabling optional USB power
management features during device transitions (device suspend/resume,
driver bind/unbind, device reset, and device disconnect).  Those
optional power features include Latency Tolerance Messaging (LTM),
USB 3.0 Link PM, and USB 2.0 Link PM.

The USB core currently enables LPM on device enumeration and disables
USB 2.0 Link PM when the device is reset.  However, the xHCI driver
disables LPM when the device is disconnected and the device context is
freed.  Push the call up into the USB core, in order to be consistent
with the core handling all power management enabling and disabling.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

How it's supposed to work:
--------------------------

USB 2.0 Link PM is a lower power state that some newer USB 2.0 devices
support.  USB 3.0 devices certified by the USB-IF are required to
support it if they are plugged into a USB 2.0 only port, or a USB 2.0
cable is used.  USB 2.0 Link PM requires both a USB device and a host
controller that supports USB 2.0 hardware-enabled LPM.

USB 2.0 Link PM is designed to be enabled once by software, and the host
hardware handles transitions to the L1 state automatically.  The premise
of USB 2.0 Link PM is to be able to put the device into a lower power
link state when the bus is idle or the device NAKs USB IN transfers for
a specified amount of time.

...but hardware is broken:
--------------------------

It turns out many USB 3.0 devices claim to support USB 2.0 Link PM (by
setting the LPM bit in their USB 2.0 BOS descriptor), but they don't
actually implement it correctly.  This manifests as the USB device
refusing to respond to transfers when it is plugged into a USB 2.0 only
port under the Haswell-ULT/Lynx Point LP xHCI host.

These devices pass the xHCI driver's simple test to enable USB 2.0 Link
PM, wait for the port to enter L1, and then bring it back into L0.  They
only start to break when L1 entry is interleaved with transfers.

Some devices then fail to respond to the next control transfer (usually
a Set Configuration).  This results in devices never enumerating.

Other mass storage devices (such as a later model Western Digital My
Passport USB 3.0 hard drive) respond fine to going into L1 between
control transfers.  They ACK the entry, come out of L1 when the host
needs to send a control transfer, and respond properly to those control
transfers.  However, when the first READ10 SCSI command is sent, the
device NAKs the data phase while it's reading from the spinning disk.
Eventually, the host requests to put the link into L1, and the device
ACKs that request.  Then it never responds to the data phase of the
READ10 command.  This results in not being able to read from the drive.

Some mass storage devices (like the Corsair Survivor USB 3.0 flash
drive) are well behaved.  They ACK the entry into L1 during control
transfers, and when SCSI commands start coming in, they NAK the requests
to go into L1, because they need to be at full power.

Not all USB 3.0 devices advertise USB 2.0 link PM support.  My Point
Grey USB 3.0 webcam advertises itself as a USB 2.1 device, but doesn't
have a USB 2.0 BOS descriptor, so we don't enable USB 2.0 Link PM.  I
suspect that means the device isn't certified.

What do we do about it?
-----------------------

There's really no good way for the kernel to test these devices.
Therefore, the kernel needs to disable USB 2.0 Link PM by default, and
distros will have to enable it by writing 1 to the sysfs file
/sys/bus/usb/devices/../power/usb2_hardware_lpm.  Rip out the xHCI Link
PM test, since it's not sufficient to detect these buggy devices, and
don't automatically enable LPM after the device is addressed.

This patch should be backported to kernels as old as 3.11, that
contain the commit a558ccdc "usb: xhci:
add USB2 Link power management BESL support".  Without this fix, some
USB 3.0 devices will not enumerate or work properly under USB 2.0 ports
on Haswell-ULT systems.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org

To enable USB 2.0 Link Power Management (LPM), the xHCI host controller
needs the device slot ID to generate the device address used in L1 entry
tokens.  That information is set in the L1 device slot ID field of the
USB 2.0 LPM registers.

Currently, the L1 device slot ID is overwritten when the xHCI driver
initiates the software test of USB 2.0 Link PM in
xhci_usb2_software_lpm_test.  It is never cleared when USB 2.0 Link PM
is disabled for the device.  That should be harmless, because the
Hardware LPM Enable (HLE) bit is cleared when USB 2.0 Link PM is
disabled, so the host should not pay attention to the slot ID.

This patch should have no effect on host behavior, but since
xhci_usb2_software_lpm_test is going away in an upcoming bug fix patch,
we need to move that code to the function that enables and disables USB
2.0 Link PM.

This patch should be backported to kernels as old as 3.11, that contain
the commit a558ccdc "usb: xhci: add USB2
Link power management BESL support".  The upcoming bug fix patch is also
marked for that stable kernel.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org

The non-DT for EXYNOS SoCs is not supported from v3.11.
Thus, there is no need to support non-DT for Exynos OHCI driver.

The 'include/linux/platform_data/usb-ohci-exynos.h' file has been
used for non-DT support. Thus, the 'usb-ohci-exynos.h' file can
be removed.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>