xhci_unmap_td_bounce_buffer() already checks for a valid td->bounce_seg
and bails out early if that's invalid. There's no need to check for this
twice.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This way we can remove checks for valid ring from call sites of
xhci_unmap_td_bounce_buffer()
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
handle_tx_event() is not releasing xhci->lock nor reacquiring it, remove
the bogus annotation.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
By extracting xhci_td_cleanup() from finish_td(), code before clearer
and easier to follow.
There are no functional changes with this patch. It's merely a cleanup.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
no functional changes. Simple cleanup to make sure variables are ordered
in a 'reverse christmas tree' fashion. While at that, also remove an
obsolete comment which doesn't apply anymore.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace list_entry() with list_first_entry() and list_for_each() with
list_for_each_entry(). This makes the code slightly more readable.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Instead of having several return points, let's use a local variable and
a single place to return. This makes the code slightly easier to read.
[set ret = IRQ_HANDLED in default working case -Mathias]
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cleanup only. This patch is a mechaninal rename to make sure our macros
for TRB completion codes match what the specification uses to refer to
such errors. The idea behind this is that it makes it far easier to grep
the specification and match it with implementation.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use list_is_singular() to check if cmd_list has only one entry.
[use list_empty() in queue command instead -Mathias]
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
No need to calculate remainder and length_field, if there is
no data phase of a control transfer.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Drop an unnecessary assignment in prepare_transfer().
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The second try was a workaround for (what we thought was) command
ring failing to stop in the first place. But this turns out to be
due to the race that we have fixed(see "xhci: Fix race related to
abort operation"). With that fix, it is time to remove the second
try.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Checking if the command timeout timer is pending when queueing the
first command to the command ring is not really useful, remove it.
Suggested-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A counter was used to find out if the stop endpoint completion raced with
the stop endpoint timeout timer. This was needed in case the stop ep
completion failed to delete the timer as it was running on anoter cpu.
The EP_STOP_CMD_PENDING flag was not enough as a new stop endpoint command
may be queued between the command completion and timeout function, which
would set the flag back.
Instead of the separate counter that was used we can detect the race by
checking both the STOP_EP_PENDING flag and timer_pending in the timeout
function.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We don't want to confuse halted and stalled endpoint states with
a flag indicating we are waiting for a stop endpoint command to
finish or timeout
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
No functional change, De Morgan !(A && B) = (!A || !B)
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a URB is killed while the host is removed we can end up in a situation
where the hub thread takes the roothub device lock, and waits for
the URB to be given back by xhci-hcd, blocking the host remove code.
xhci-hcd tries to stop the endpoint and give back the urb, but can't
as the host is removed from PCI bus at the same time, preventing the normal
way of giving back urb.
Instead we need to rely on the stop command timeout function to give back
the urb. This xhci_stop_endpoint_command_watchdog() timeout function
used a XHCI_STATE_DYING flag to indicate if the timeout function is already
running, but later this flag has been taking into use in other places to
mark that xhci is dying.
Remove checks for XHCI_STATE_DYING in xhci_urb_dequeue. We are still
checking that reading from pci state does not return 0xffffffff or that
host is not halted before trying to stop the endpoint.
This whole area of stopping endpoints, giving back URBs, and the wathdog
timeout need rework, this fix focuses on solving a specific deadlock
issue that we can then send to stable before any major rework.
Cc: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stop Endpoint command can come at any point and we
have no control of that. We should make sure to
handle COMP_STOP on SETUP phase as well, otherwise
urb->actual_length might be set to negative values
in some occasions such as below:
urb->length = 4;
build_control_transfer_td_for(urb, ep);
stop_endpoint(ep);
COMP_STOP:
[...]
urb->actual_length = urb->length - trb->length;
trb->length is 8 for SETUP stage (8 control request
bytes), so actual_length would be set to -4 in this
case.
While doing that, also make sure to use TRB_TYPE
field of the actual TRB instead of matching pointers
to figure out in which stage of the control transfer
we got our completion event.
Cc: <stable@vger.kernel.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Current abort operation has race.
xhci_handle_command_timeout()
xhci_abort_cmd_ring()
xhci_write_64(CMD_RING_ABORT)
xhci_handshake(5s)
do {
check CMD_RING_RUNNING
udelay(1)
...
COMP_CMD_ABORT event
COMP_CMD_STOP event
xhci_handle_stopped_cmd_ring()
restart cmd_ring
CMD_RING_RUNNING become 1 again
} while ()
return -ETIMEDOUT
xhci_write_64(CMD_RING_ABORT)
/* can abort random command */
To do abort operation correctly, we have to wait both of COMP_CMD_STOP
event and negation of CMD_RING_RUNNING.
But like above, while timeout handler is waiting negation of
CMD_RING_RUNNING, event handler can restart cmd_ring. So timeout
handler never be notice negation of CMD_RING_RUNNING, and retry of
CMD_RING_ABORT can abort random command (BTW, I guess retry of
CMD_RING_ABORT was workaround of this race).
To fix this race, this moves xhci_handle_stopped_cmd_ring() to
xhci_abort_cmd_ring(). And timeout handler waits COMP_CMD_STOP event.
At this point, timeout handler is owner of cmd_ring, and safely
restart cmd_ring by using xhci_handle_stopped_cmd_ring().
[FWIW, as bonus, this way would be easily extend to add CMD_RING_PAUSE
operation]
[locks edited as patch is rebased on other locking fixes -Mathias]
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is preparation to fix abort operation race (See "xhci: Fix race
related to abort operation"). To make timeout sleepable, use
delayed_work instead of timer.
[change a newly added pending timer fix to pending work -Mathias]
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In command timer function, xhci_handle_command_timeout(), xhci->lock
is unlocked before call into xhci_abort_cmd_ring(). This might cause
race between the timer function and the event handler.
The xhci_abort_cmd_ring() function sets the CMD_RING_ABORT bit in the
command register and polling it until the setting takes effect. A stop
command ring event might be handled between writing the abort bit and
polling for it. The event handler will restart the command ring, which
causes the failure of polling, and we ever believed that we failed to
stop it.
As a bonus, this also fixes some issues of calling functions without
locking in xhci_handle_command_timeout().
Cc: <stable@vger.kernel.org> # 3.7+
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If we get a command completion event at the same time as the command
timeout work starts on another cpu we might end up aborting the wrong
command.
If the command completion takes the xhci lock before the timeout work, it
will handle the command, pick the next command, mark it as current_cmd, and
re-queue the timeout work. When the timeout work finally gets the lock
It will start aborting the wrong command.
This case can be resolved by checking if the timeout work is pending inside
the timeout function itself. A new timeout work can only be pending if the
command completed and a new command was queued.
If there are no more commands pending then command completion will set
the current_cmd to NULL, which is already handled in the timeout work.
Cc: <stable@vger.kernel.org>
Reported-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When current command was supposed to be aborted, host will free the command
in handle_cmd_completion() function. But it might be still referenced by
xhci->current_cmd, which need to set NULL.
Cc: <stable@vger.kernel.org>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
handle_cmd_completion() frees a command structure which might be still
referenced by xhci->current_cmd.
This might cause problem when xhci->current_cmd is accessed after that.
A real-life case could be like this. The host takes a very long time to
respond to a command, and the command timer is fired at the same time
when the command completion event arrives. The command completion
handler frees xhci->current_cmd before the timer function can grab
xhci->lock. Afterward, timer function grabs the lock and go ahead with
checking and setting members of xhci->current_cmd.
Cc: <stable@vger.kernel.org> # v3.16+
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
One big merge this time with a total of 166 non-merge commits.
Most of the work, by far, is on dwc2 this time (68.2%) with dwc3 a far
second (22.5%). The remaining 9.3% are scattered on gadget drivers.
The most important changes for dwc2 are the peripheral side DMA support
implemented by Synopsys folks and support for the new IOT dwc2
compatible core from Synopsys.
In dwc3 land we have support for high-bandwidth, high-speed isochronous
endpoints and some non-critical fixes for large scatter lists.
Apart from these, we have our usual set of cleanups, non-critical fixes,
etc.
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Merge tag 'usb-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-next
Felipe writes:
usb: patches for v4.10 merge window
One big merge this time with a total of 166 non-merge commits.
Most of the work, by far, is on dwc2 this time (68.2%) with dwc3 a far
second (22.5%). The remaining 9.3% are scattered on gadget drivers.
The most important changes for dwc2 are the peripheral side DMA support
implemented by Synopsys folks and support for the new IOT dwc2
compatible core from Synopsys.
In dwc3 land we have support for high-bandwidth, high-speed isochronous
endpoints and some non-critical fixes for large scatter lists.
Apart from these, we have our usual set of cleanups, non-critical fixes,
etc.
xhci->slot_id is used for providing a way to pass slot id from the
command completion handler to the function waiting for completion.
It's shared by enumerations of all USB devices connected to an
xhci host. Hence, it's a source for possible races. Since we've
introduced command structure and the command queue to xhci driver.
It's better to move slot_id from xhci_hcd structure to xhci_command
structure. Hence the race source is removed.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
define GET_EP_CTX_STATE() macro to get the endpoint state from a
pointer to a le32 enpoint context structure
No functional changes
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In xhci_handle_event(), when errors are detected, driver always sets
a bit in error_bitmask (one member of the xhci private driver data).
That means users have to retrieve and decode the value of error_bitmask
in xhci private driver data if they want to know whether those erros
ever happened in xhci_handle_event(). Otherwise, those errors are just
ignored silently.
This patch cleans up this by replacing the setting of error_bitmask
with the kernel print functions, so that users can easily check and
report the errors happened in xhci_handle_event().
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We want one function that gives back urb in interrupt that can
be used in both normal cases and when killing off urbs.
Add small helpers that check if td is last_td_in_urb() and
that increase the td count of a urb inc_td_cnt()
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mostly refactoring and code cleanup.
while handling transfer events we used to check the return value of
various functions to see if we can give back the URB.
Turns out the only case when those return values are set are when
finish_td() notices we are completing the last td in the URB.
give back the urb directly in finish_td() instead.
Only functional change is that we now increase the event ring dequeue
pointer in sowtware after giving back the URB. This should not matter
as we are in hardware interrupt context and the time when writing the
new event ring dequeue to hardware remains the same.
Hardware is the only one that can put event TRBs on the event ring.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move giving back the urb to a separate function
No functional changes
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes the following sparse warning:
drivers/usb/host/xhci-ring.c:608:6: warning:
symbol 'xhci_unmap_td_bounce_buffer' was not declared.
Should it be static?
Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
No functional changes but a few debugging outputs removed
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Renaming variables, no functional changes
Event trbs on the event ring cointain a pointer to the transfer trb
on a endpoint ring that caused the event.
The naming has been very confusing as the event trb was called "event"
and the endpoint transfer trb was called "event_trb".
rename all variables that are realated to the endpoint transfer trb
from event_* to ep_*
No functional changes
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mostly refactoring, but does also change error message if
we get a bad length in the event trb.
Adds a helper function to sum trb lengths of partial TDs
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Refactor pricess_ctrl_tx() to make it more readable
No functional changes
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We only check for the URB_SHORT_NOT_OK urb flag to set the urb status
to -EREMOTEIO for transfers that didn't transfer all data.
This will be done in __usb_hcd_giveback() for other than isoc tranfers,
so remove the redundant check from xhci.
Also fix a couple split lines in debug messages to make them greppable.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
replace the complex check for noop with a simple helper
Improve code readability
No functional changes
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the trb_is_link() and link_trb_toggles_cycle() helpers to
make the code more readable
No functional changes
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fist function called in xhci_halt is xhci_quiesce, so no point
in calling it twice
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usb_endpoint_maxp() is now returning maxpacket
correctly - iow only bits 10:0. We can finaly remove
XHCI's private GET_MAX_PACKET macro.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
The stop endpoint command has its own 5 second timeout timer.
If the timeout function is triggered between USB3 and USB2 host
removal it will try to call usb_hc_died(xhci_to_hcd(xhci)->primary_hcd)
the ->primary_hcd will be set to NULL at USB3 hcd removal.
Fix this by first checking if the PCI host is being removed, and
also by using only xhci_to_hcd() as it will always return the primary
hcd.
CC: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Enqueue the first TRB even if full_len is zero.
Without this "adb install <apk>" freezes the system.
Signed-off-by: Alban Browaeys <alban.browaeys@gmail.com>
Fixes: 86065c2719 ("xhci: don't rely on precalculated value of needed trbs in the enqueue loop")
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix "Command completion event does not match command" errors by always
handling the command ring stopped events.
The command ring stopped event is generated as a result of aborting
or stopping the command ring with a register write. It is not caused
by a command in the command queue, and thus won't have a matching command
in the comman list.
Solve it by handling the command ring stopped event before checking for a
matching command.
In most command time out cases we abort the command ring, and get
a command ring stopped event. The events command pointer will point at
the current command ring dequeue, which in most cases matches the timed
out command in the command list, and no error messages are seen.
If we instead get a command aborted event before the command ring stopped
event, the abort event will increse the command ring dequeue pointer, and
the following command ring stopped events command pointer will point at the
next, not yet queued command. This case triggered the error message
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gcc warns about what first looks like a reference to an uninitialized
variable:
drivers/usb/host/xhci-ring.c: In function 'handle_cmd_completion':
drivers/usb/host/xhci-ring.c:753:4: error: 'ep_ring' may be used uninitialized in this function [-Werror=maybe-uninitialized]
xhci_unmap_td_bounce_buffer(xhci, ep_ring, cur_td);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/usb/host/xhci-ring.c:647:20: note: 'ep_ring' was declared here
struct xhci_ring *ep_ring;
^~~~~~~
It's clear to see that the list_empty() check means it can never be
uninitialized, however it still looks wrong:
When ep->cancelled_td_list contains more than one entry, the
ep_ring variable will point to the ring that was retrieved
from the last urb, and we have to look it up again in the
second loop instead, which fixes the behavior and gets rid of the
warning too.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: f9c589e142 ("xhci: TD-fragment, align the unsplittable case with a bounce buffer")
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's only used with rings that have link trbs
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Only used in one place, replace with trb_is_link() helper
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
inc_deq() is called both for rings with link trbs and the event ring
without link trbs.
The last_trb() check in inc_deq() has a off by one error, going beyond
allocated array when checking if trb == [TRBS_PER_SEGMENT], and the whole
inc_deq() depend on this.
Rewrite the inc_deq() funciton, remove the faulty last_trb() helper, add
new last_trb_on_seg() and last_trb_on_ring() helpers
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a new is_link_trb() function that only checks for link trbs.
We want to split generic last_trb() function which is used for both
event rings without link trbs, and endpoint and command rings with links.
This will allow us to easier check for link trbs added mid segments.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Felipe Balbi