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: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah 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: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah 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: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah 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: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah 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: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah 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: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah 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: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah 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: Xenia Ragiadakou <burzalodowa@gmail.com>
Acked-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Sarah 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: Xenia Ragiadakou <burzalodowa@gmail.com>
Acked-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
The halted state of a endpoint cannot be cleared over CLEAR_HALT from a
user process, because the stopped_td variable was overwritten in the
handle_stopped_endpoint() function. So the xhci_endpoint_reset() function will
refuse the reset and communication with device can not run over this endpoint.
https://bugzilla.kernel.org/show_bug.cgi?id=60699
Signed-off-by: Florian Wolter <wolly84@web.de>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
When a device signals remote wakeup on a roothub, and the suspend change
bit is set, the host controller driver must not give control back to the
USB core until the port goes back into the active state.
EHCI accomplishes this by waiting in the get port status function until
the PORT_RESUME bit is cleared:
/* stop resume signaling */
temp &= ~(PORT_RWC_BITS | PORT_SUSPEND | PORT_RESUME);
ehci_writel(ehci, temp, status_reg);
clear_bit(wIndex, &ehci->resuming_ports);
retval = ehci_handshake(ehci, status_reg,
PORT_RESUME, 0, 2000 /* 2msec */);
Similarly, the xHCI host should wait until the port goes into U0, before
passing control up to the USB core. When the port transitions from the
RExit state to U0, the xHCI driver will get a port status change event.
We need to wait for that event before passing control up to the USB
core.
After the port transitions to the active state, the USB core should time
a recovery interval before it talks to the device. The length of that
recovery interval is TRSMRCY, 10 ms, mentioned in the USB 2.0 spec,
section 7.1.7.7. The previous xHCI code (which did not wait for the
port to go into U0) would cause the USB core to violate that recovery
interval.
This bug caused numerous USB device disconnects on remote wakeup under
ChromeOS and a Lynx Point LP xHCI host that takes up to 20 ms to move
from RExit to U0. ChromeOS is very aggressive about power savings, and
sets the autosuspend_delay to 100 ms, and disables USB persist.
I attempted to replicate this bug with Ubuntu 12.04, but could not. I
used Ubuntu 12.04 on the same platform, with the same BIOS that the bug
was triggered on ChromeOS with. I also changed the USB sysfs settings
as described above, but still could not reproduce the bug under Ubuntu.
It may be that ChromeOS userspace triggers this bug through additional
settings.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
If a command on the command ring needs to be cancelled before it is handled
it can be turned to a no-op operation when the ring is stopped.
We want to store the command ring enqueue pointer in the command structure
when the command in enqueued for the cancellation case.
Some commands used to store the command ring dequeue pointers instead of enqueue
(these often worked because enqueue happends to equal dequeue quite often)
Other commands correctly used the enqueue pointer but did not check if it pointed
to a valid trb or a link trb, this caused for example stop endpoint command to timeout in
xhci_stop_device() in about 2% of suspend/resume cases.
This should also solve some weird behavior happening in command cancellation cases.
This patch is based on a patch submitted by Sarah Sharp to linux-usb, but
then forgotten:
http://marc.info/?l=linux-usb&m=136269803207465&w=2
This patch should be backported to kernels as old as 3.7, that contain
the commit b92cc66c04 "xHCI: add aborting
command ring function"
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
When a command times out, the command ring is first aborted,
and then stopped. If the command ring is empty when it is stopped
the stop event will point to next command which is not yet set.
xHCI tries to handle this next event often causing an oops.
Don't handle command completion events on stopped cmd ring if ring is
empty.
This patch should be backported to kernels as old as 3.7, that contain
the commit b92cc66c04 "xHCI: add aborting
command ring function"
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Reported-by: Giovanni <giovanni.nervi@yahoo.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
When debug is not enabled and dev_dbg() will expand to nothing,
log might be flooded with "callbacks suppressed". If it was not
done on purpose, better to use dev_dbg_ratelimited() instead.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
This patch defines a new trace event, which is called xhci_dbg_ring_expansion
and belongs to the event class xhci_log_msg, and adds tracepoints that trace
the debug messages associated with the expansion of endpoint ring when there
is not enough space allocated to hold all pending TRBs.
Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
This patch defines a new trace event, which is called xhci_dbg_cancel_urb
and belongs to the event class xhci_log_msg, and adds tracepoints that
trace the debug messages related to the removal of a cancelled URB from
the endpoint's transfer ring.
Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
This patch creates a new event class, called xhci_log_event,
and defines the xhci_cmd_completion trace event used for
tracing the commands issued to xHC that generate a completion
event in the event ring.
This info can be used, later, to print, in a human readable
way, the completion status and flags as well as the command's
type and fields using the trace-cmd tool and the appropriate
plugin.
Also, a tracepoint is added in handle_cmd_completion().
Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
This patch defines a new trace event, which is called xhci_dbg_reset_ep
and belongs in the event class xhci_log_msg, and adds tracepoints that
trace the debug messages associated with resetting an endpoint after
the reception of a STALL packet.
Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
This patch defines a new trace event, which is called xhci_dbg_quirks
and belongs in the event class xhci_log_msg, and adds tracepoints that
trace the debug messages associated with xHCs' quirks.
Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
This patch defines a new trace event, which is called xhci_dbg_context_change
and belongs in the event class xhci_log_msg, and adds tracepoints for tracing
the debug messages related to context updates performed with Configure Endpoint
and Evaluate Context commands.
Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
in some cases where device is attched to xhci port and do not responding,
for example ath9k_htc with stalled firmware, kernel will
crash on ring_doorbell_for_active_rings.
This patch check if pointer exist before it is used.
This patch should be backported to kernels as old as 2.6.35, that
contain the commit e9df17eb14 "USB: xhci:
Correct assumptions about number of rings per endpoint"
Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
Fail gracefully, instead of causing the kernel to panic, if the input
control context doesn't have the right type (XHCI_CTX_TYPE_INPUT). Push
finding the pointer to the input control context up into functions that
can fail.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: John Youn <johnyoun@synopsys.com>
According to Felipe and Alan's comments the second parameter of irq
handler should be 'void *' not a specific structure pointer.
So change it.
Signed-off-by: Alex Shi <alex.shi@intel.com>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
When a device attached to the roothub is suspended, the endpoint rings
are stopped. The host may generate a completion event with the
completion code set to 'Stopped' or 'Stopped Invalid' when the ring is
halted. The current xHCI code prints a warning in that case, which can
be really annoying if the USB device is coming into and out of suspend.
Remove the unnecessary warning.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: Stephen Hemminger <stephen@networkplumber.org>
Use proper macro while extracting TRB transfer length from
Transfer event TRBs. Adding a macro EVENT_TRB_LEN (bits 0:23)
for the same, and use it instead of TRB_LEN (bits 0:16) in
case of event TRBs.
This patch should be backported to kernels as old as 2.6.31, that
contain the commit b10de14211 "USB: xhci:
Bulk transfer support". This patch will have issues applying to older
kernels.
Signed-off-by: Vivek gautam <gautam.vivek@samsung.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
/home/b29397/work/code/git/linus/linux-2.6/drivers/usb/host/xhci-ring.c: In function ‘handle_port_status’:
/home/b29397/work/code/git/linus/linux-2.6/drivers/usb/host/xhci-ring.c:1580: warning: ‘hcd’ may be used uninitialized in this function
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
This pulls in a bunch of fixes that are in Linus's tree because we need them
here for testing and development.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch (as1640) fixes a memory leak in xhci-hcd. The urb_priv
data structure isn't always deallocated in the handle_tx_event()
routine for non-control transfers. The patch adds a kfree() call so
that all paths end up freeing the memory properly.
This patch should be backported to kernels as old as 2.6.36, that
contain the commit 8e51adccd4 "USB: xHCI:
Introduce urb_priv structure"
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-and-tested-by: Martin Mokrejs <mmokrejs@fold.natur.cuni.cz>
CC: <stable@vger.kernel.org>
Fix incorrect bit test that originally showed up in
4ee823b83b "USB/xHCI: Support
device-initiated USB 3.0 resume."
Use '&' instead of '&&'.
This should be backported to kernels as old as 3.4.
Signed-off-by: Nickolai Zeldovich <nickolai@csail.mit.edu>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
To calculate the TD size for a particular TRB in an isoc TD, we need
know the endpoint's max packet size. Isochronous endpoints also encode
the number of additional service opportunities in their wMaxPacketSize
field. The TD size calculation did not mask off those bits before using
the field. This resulted in incorrect TD size information for
isochronous TRBs when an URB frame buffer crossed a 64KB boundary.
For example:
- an isoc endpoint has 2 additional service opportunites and
a max packet size of 1020 bytes
- a frame transfer buffer contains 3060 bytes
- one frame buffer crosses a 64KB boundary, and must be split into
one 1276 byte TRB, and one 1784 byte TRB.
The TD size is is the number of packets that remain to be transferred
for a TD after processing all the max packet sized packets in the
current TRB and all previous TRBs.
For this TD, the number of packets to be transferred is (3060 / 1020),
or 3. The first TRB contains 1276 bytes, which means it contains one
full packet, and a 256 byte remainder. After processing all the max
packet-sized packets in the first TRB, the host will have 2 packets left
to transfer.
The old code would calculate the TD size for the first TRB as:
total packet count = DIV_ROUND_UP (TD length / endpoint wMaxPacketSize)
total packet count - (first TRB length / endpoint wMaxPacketSize)
The math should have been:
total packet count = DIV_ROUND_UP (3060 / 1020) = 3
3 - (1276 / 1020) = 2
Since the old code didn't mask off the additional service interval bits
from the wMaxPacketSize field, the math ended up as
total packet count = DIV_ROUND_UP (3060 / 5116) = 1
1 - (1276 / 5116) = 1
Fix this by masking off the number of additional service opportunities
in the wMaxPacketSize field.
This patch should be backported to stable kernels as old as 3.0, that
contain the commit 4da6e6f247 "xhci 1.0:
Update TD size field format." It may not apply well to kernels older
than 3.2 because of commit 29cc88979a
"USB: use usb_endpoint_maxp() instead of le16_to_cpu()".
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
An isochronous TD is comprised of one isochronous TRB chained to zero or
more normal TRBs. Only the isoc TRB has the TBC and TLBPC fields. The
normal TRBs must set those fields to zeroes. The code was setting the
TBC and TLBPC fields for both isoc and normal TRBs. Fix this.
This should be backported to stable kernels as old as 3.0, that contain
the commit b61d378f2d " xhci 1.0: Set
transfer burst last packet count field."
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
The union xhci_trb *trb variable is defined and assigned
inside the xHCI IRQ handler function but is never used.
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
The USB core hub thread (khubd) is designed with external USB hubs in
mind. It expects that if a port status change bit is set, the hub will
continue to send a notification through the hub status data transfer.
Basically, it expects hub notifications to be level-triggered.
The xHCI host controller is designed to be edge-triggered on the logical
'OR' of all the port status change bits. When all port status change
bits are clear, and a new change bit is set, the xHC will generate a
Port Status Change Event. If another change bit is set in the same port
status register before the first bit is cleared, it will not send
another event.
This means that the hub code may lose port status changes because of
race conditions between clearing change bits. The user sees this as a
"dead port" that doesn't react to device connects.
The fix is to turn on port polling whenever a new change bit is set.
Once the USB core issues a hub status request that shows that no change
bits are set in any USB ports, turn off port polling.
We can't allow the USB core to poll the roothub for port events during
host suspend because if the PCI host is in D3cold, the port registers
will be all f's. Instead, stop the port polling timer, and
unconditionally restart it when the host resumes. If there are no port
change bits set after the resume, the first call to hub_status_data will
disable polling.
This patch should be backported to stable kernels with the first xHCI
support, 2.6.31 and newer, that include the commit
0f2a79300a "USB: xhci: Root hub support."
There will be merge conflicts because the check for HC_STATE_SUSPENDED
was moved into xhci_suspend in 3.8.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable@vger.kernel.org
The xHCI 1.0 specification made a change to the TD Size field in TRBs.
The value is now the number of packets that remain to be sent in the TD,
not including this TRB. The TD Size value for the last TRB in a TD must
always be zero.
The xHCI function xhci_v1_0_td_remainder() attempts to calculate this,
but it gets it wrong. First, it erroneously reuses the old
xhci_td_remainder function, which will right shift the value by 10. The
xHCI 1.0 spec as of June 2011 says nothing about right shifting by 10.
Second, it does not set the TD size for the last TRB in a TD to zero.
Third, it uses roundup instead of DIV_ROUND_UP. The total packet count
is supposed to be the total number of bytes in this TD, divided by the
max packet size, rounded up. DIV_ROUND_UP is the right function to use
in that case.
With the old code, a TD on an endpoint with max packet size 1024 would
be set up like so:
TRB 1, TRB length = 600 bytes, TD size = 0
TRB 1, TRB length = 200 bytes, TD size = 0
TRB 1, TRB length = 100 bytes, TD size = 0
With the new code, the TD would be set up like this:
TRB 1, TRB length = 600 bytes, TD size = 1
TRB 1, TRB length = 200 bytes, TD size = 1
TRB 1, TRB length = 100 bytes, TD size = 0
This commit should be backported to kernels as old as 3.0, that contain
the commit 4da6e6f247 "xhci 1.0: Update TD
size field format."
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: Chintan Mehta <chintan.mehta@sibridgetech.com>
Reported-by: Shimmer Huang <shimmering.h@gmail.com>
Tested-by: Bhavik Kothari <bhavik.kothari@sibridgetech.com>
Tested-by: Shimmer Huang <shimmering.h@gmail.com>
Cc: stable@vger.kernel.org
Non-static xHCI driver symbols should start with the "xhci_" prefix, in
order to avoid namespace pollution. Rename the "handshake" function to
"xhci_handshake".
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: Ben Hutchings <ben@decadent.org.uk>
The command cancellation code doesn't check whether find_trb_seg()
couldn't find the segment that contains the TRB to be canceled. This
could cause a NULL pointer deference later in the function when next_trb
is called. It's unlikely to happen unless something is wrong with the
command ring pointers, so add some debugging in case it happens.
This patch should be backported to stable kernels as old as 3.0, that
contain the commit b63f4053cc "xHCI:
handle command after aborting the command ring".
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
When a device with an isochronous endpoint is behind a hub plugged into
the Intel Panther Point xHCI host controller, and the driver submits
multiple frames per URB, the xHCI driver will set the Block Event
Interrupt (BEI) flag on all but the last TD for the URB. This causes
the host controller to place an event on the event ring, but not send an
interrupt. When the last TD for the URB completes, BEI is cleared, and
we get an interrupt for the whole URB.
However, under a Panther Point xHCI host controller, if the parent hub
is unplugged when one or more events from transfers with BEI set are on
the event ring, a port status change event is placed on the event ring,
but no interrupt is generated. This means URBs stop completing, and the
USB device disconnect is not noticed. Something like a USB headset will
cause mplayer to hang when the device is disconnected.
If another transfer is sent (such as running `sudo lsusb -v`), the next
transfer event seems to "unstick" the event ring, the xHCI driver gets
an interrupt, and the disconnect is reported to the USB core.
The fix is not to use the BEI flag under the Panther Point xHCI host.
This will impact power consumption and system responsiveness, because
the xHCI driver will receive an interrupt for every frame in all
isochronous URBs instead of once per URB.
Intel chipset developers confirm that this bug will be hit if the BEI
flag is used on any endpoint, not just ones that are behind a hub.
This patch should be backported to kernels as old as 3.0, that contain
the commit 69e848c209 "Intel xhci: Support
EHCI/xHCI port switching."
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
removes unnecessary semicolon
Found by Coccinelle: http://coccinelle.lip6.fr/
Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
drivers/usb/host/xhci.c:1826:14: warning: symbol 'xhci_get_block_size' was not declared. Should it be static?
drivers/usb/host/xhci.c:1844:14: warning: symbol 'xhci_get_largest_overhead' was not declared. Should it be static?
drivers/usb/host/xhci-ring.c:2304:36: warning: context imbalance in 'handle_tx_event' - unexpected unlock
drivers/usb/host/xhci-hub.c:425:6: warning: symbol 'xhci_set_remote_wake_mask' was not declared. Should it be static?
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
According to xHCI spec section 4.6.1.1 and section 4.6.1.2,
after aborting a command on the command ring, xHC will
generate a command completion event with its completion
code set to Command Ring Stopped at least. If a command is
currently executing at the time of aborting a command, xHC
also generate a command completion event with its completion
code set to Command Abort. When the command ring is stopped,
software may remove, add, or rearrage Command Descriptors.
To cancel a command, software will initialize a command
descriptor for the cancel command, and add it into a
cancel_cmd_list of xhci. When the command ring is stopped,
software will find the command trbs described by command
descriptors in cancel_cmd_list and modify it to No Op
command. If software can't find the matched trbs, we can
think it had been finished.
This patch should be backported to kernels as old as 3.0, that contain
the commit 7ed603ecf8 "xhci: Add an
assertion to check for virt_dev=0 bug." That commit papers over a NULL
pointer dereference, and this patch fixes the underlying issue that
caused the NULL pointer dereference.
Signed-off-by: Elric Fu <elricfu1@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: Miroslav Sabljic <miroslav.sabljic@avl.com>
Cc: stable@vger.kernel.org
Software have to abort command ring and cancel command
when a command is failed or hang. Otherwise, the command
ring will hang up and can't handle the others. An example
of a command that may hang is the Address Device Command,
because waiting for a SET_ADDRESS request to be acknowledged
by a USB device is outside of the xHC's ability to control.
To cancel a command, software will initialize a command
descriptor for the cancel command, and add it into a
cancel_cmd_list of xhci.
Sarah: Fixed missing newline on "Have the command ring been stopped?"
debugging statement.
This patch should be backported to kernels as old as 3.0, that contain
the commit 7ed603ecf8 "xhci: Add an
assertion to check for virt_dev=0 bug." That commit papers over a NULL
pointer dereference, and this patch fixes the underlying issue that
caused the NULL pointer dereference.
Signed-off-by: Elric Fu <elricfu1@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: Miroslav Sabljic <miroslav.sabljic@avl.com>
Cc: stable@vger.kernel.org
Adding cmd_ring_state for command ring. It helps to verify
the current command ring state for controlling the command
ring operations.
This patch should be backported to kernels as old as 3.0. The commit
7ed603ecf8 "xhci: Add an assertion to
check for virt_dev=0 bug." papers over the NULL pointer dereference that
I now believe is related to a timed out Set Address command. This (and
the four patches that follow it) contain the real fix that also allows
VIA USB 3.0 hubs to consistently re-enumerate during the plug/unplug
stress tests.
Signed-off-by: Elric Fu <elricfu1@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: Miroslav Sabljic <miroslav.sabljic@avl.com>
Cc: stable@vger.kernel.org
This patch fixes a particularly nasty bug that was revealed by the ring
expansion patches. The bug has been present since the very beginning of
the xHCI driver history, and could have caused general protection faults
from bad memory accesses.
The first thing to note is that a Set TR Dequeue Pointer command can
move the dequeue pointer to a link TRB, if the canceled or stalled
transfer TD ended just before a link TRB. The function to increment the
dequeue pointer, inc_deq, was written before cancellation and stall
support was added. It assumed that the dequeue pointer could never
point to a link TRB. It would unconditionally increment the dequeue
pointer at the start of the function, check if the pointer was now on a
link TRB, and move it to the top of the next segment if so.
This means that if a Set TR Dequeue Point command moved the dequeue
pointer to a link TRB, a subsequent call to inc_deq() would move the
pointer off the segment and into la-la-land. It would then read from
that memory to determine if it was a link TRB. Other functions would
often call inc_deq() until the dequeue pointer matched some other
pointer, which means this function would quite happily read all of
system memory before wrapping around to the right pointer value.
Often, there would be another endpoint segment from a different ring
allocated from the same DMA pool, which would be contiguous to the
segment inc_deq just stepped off of. inc_deq would eventually find the
link TRB in that segment, and blindly move the dequeue pointer back to
the top of the correct ring segment.
The only reason the original code worked at all is because there was
only one ring segment. With the ring expansion patches, the dequeue
pointer would eventually wrap into place, but the dequeue segment would
be out-of-sync. On the second TD after the dequeue pointer was moved to
a link TRB, trb_in_td() would fail (because the dequeue pointer and
dequeue segment were out-of-sync), and this message would appear:
ERROR Transfer event TRB DMA ptr not part of current TD
This fixes bugzilla entry 4333 (option-based modem unhappy on USB 3.0
port: "Transfer event TRB DMA ptr not part of current TD", "rejecting
I/O to offline device"),
https://bugzilla.kernel.org/show_bug.cgi?id=43333
and possibly other general protection fault bugs as well.
This patch should be backported to kernels as old as 2.6.31. A separate
patch will be created for kernels older than 3.4, since inc_deq was
modified in 3.4 and this patch will not apply.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: James Ettle <theholyettlz@googlemail.com>
Tested-by: Matthew Hall <mhall@mhcomputing.net>
Cc: stable@vger.kernel.org
When we encounter an xHCI host that needs the XHCI_TRUST_TX_LENGTH
quirk, the xHCI driver ends up spewing messages about the quirk into
dmesg every time a short packet occurs. Change the xHCI driver to
rate-limit such warnings.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: Matthew Hall <mhall@mhcomputing.net>
Reported-by: Gary E. Miller <gem@rellim.com>
The Microsoft LifeChat 3000 USB headset was causing a very reproducible
hang whenever it was plugged in. At first, I thought the host
controller was producing bad transfer events, because the log was filled
with errors like:
xhci_hcd 0000:00:14.0: ERROR Transfer event TRB DMA ptr not part of current TD
However, it turned out to be an xHCI driver bug in the ring expansion
patches. The bug is triggered When there are two ring segments, and a
TD that ends just before a link TRB, like so:
______________ _____________
| | ---> | setup TRB B |
______________ | _____________
| | | | data TRB B |
______________ | _____________
| setup TRB A | <-- deq | | data TRB B |
______________ | _____________
| data TRB A | | | | <-- enq, deq''
______________ | _____________
| status TRB A | | | |
______________ | _____________
| link TRB |--------------- | link TRB |
_____________ <--- deq' _____________
TD A (the first control transfer) stalls on the data phase. That halts
the ring. The xHCI driver moves the hardware dequeue pointer to the
first TRB after the stalled transfer, which happens to be the link TRB.
Once the Set TR dequeue pointer command completes, the function
update_ring_for_set_deq_completion runs. That function is supposed to
update the xHCI driver's dequeue pointer to match the internal hardware
dequeue pointer. On the first call this would work fine, and the
software dequeue pointer would move to deq'.
However, if the transfer immediately after that stalled (TD B in this
case), another Set TR Dequeue command would be issued. That would move
the hardware dequeue pointer to deq''. Once that command completed,
update_ring_for_set_deq_completion would run again.
The original code would unconditionally increment the software dequeue
pointer, which moved the pointer off the ring segment into la-la-land.
The while loop would happy increment the dequeue pointer (possibly
wrapping it) until it matched the hardware pointer value.
The while loop would also access all the memory in between the first
ring segment and the second ring segment to determine if it was a link
TRB. This could cause general protection faults, although it was
unlikely because the ring segments came from a DMA pool, and would often
have consecutive memory addresses.
If nothing in that space looked like a link TRB, the deq_seg pointer for
the ring would remain on the first segment. Thus, the deq_seg and the
software dequeue pointer would get out of sync.
When the next transfer event came in after the stalled transfer, the
xHCI driver code would attempt to convert the software dequeue pointer
into a DMA address in order to compare the DMA address for the completed
transfer. Since the deq_seg and the dequeue pointer were out of sync,
xhci_trb_virt_to_dma would return NULL.
The transfer event would get ignored, the transfer would eventually
timeout, and we would mistakenly convert the finished transfer to no-op
TRBs. Some kernel driver (maybe xHCI?) would then get stuck in an
infinite loop in interrupt context, and the whole machine would hang.
This patch should be backported to kernels as old as 3.4, that contain
the commit b008df60c6 "xHCI: count free
TRBs on transfer ring"
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Andiry Xu <andiry.xu@amd.com>
Cc: stable@vger.kernel.org
The upcoming USB 3.0 Link PM patches will introduce new API to enable
and disable low-power link states. We must be able to disable LPM in
order to reset a device, or place the device into U3 (device suspend).
Therefore, we need to make sure the Evaluate Context command to disable
the LPM timeouts can't fail due to there being no room on the command
ring.
Introduce a new flag to the function that queues the Evaluate Context
command, command_must_succeed. This tells the ring handler that a TRB
has already been reserved for the command (by incrementing
xhci->cmd_ring_reserved_trbs), and basically ensures that prepare_ring()
won't fail. A similar flag was already implemented for the Configure
Endpoint command queuing function.
All functions that currently call xhci_configure_endpoint() to issue an
Evaluate Context command pass "false" for the "must_succeed" parameter,
so this patch should have no effect on current xHCI driver behavior.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Sergio reported that when he recorded audio from a USB headset mic
plugged into the USB 3.0 port on his ASUS N53SV-DH72, the audio sounded
"robotic". When plugged into the USB 2.0 port under EHCI on the same
laptop, the audio sounded fine. The device is:
Bus 002 Device 004: ID 046d:0a0c Logitech, Inc. Clear Chat Comfort USB Headset
The problem was tracked down to the Fresco Logic xHCI host controller
not correctly reporting short transfers on isochronous IN endpoints.
The driver would submit a 96 byte transfer, the device would only send
88 or 90 bytes, and the xHCI host would report the transfer had a
"successful" completion code, with an untransferred buffer length of 8
or 6 bytes.
The successful completion code and non-zero untransferred length is a
contradiction. The xHCI host is supposed to only mark a transfer as
successful if all the bytes are transferred. Otherwise, the transfer
should be marked with a short packet completion code. Without the EHCI
bus trace, we wouldn't know whether the xHCI driver should trust the
completion code or the untransferred length. With it, we know to trust
the untransferred length.
Add a new xHCI quirk for the Fresco Logic host controller. If a
transfer is reported as successful, but the untransferred length is
non-zero, print a warning. For the Fresco Logic host, change the
completion code to COMP_SHORT_TX and process the transfer like a short
transfer.
This should be backported to stable kernels that contain the commit
f5182b4155 "xhci: Disable MSI for some
Fresco Logic hosts." That commit was marked for stable kernels as old
as 2.6.36.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: Sergio Correia <lists@uece.net>
Tested-by: Sergio Correia <lists@uece.net>
Cc: stable@vger.kernel.org
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
This patch changes the output format specifier of a debugging line in
the xhci-hcd driver. An URB's transfer_buffer_length should be
printed in decimal; there's no reason to print it in hex. Especially
since the actual_length value, printed earlier on the same line, is
already in decimal.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
While testing unplugging an UVC HD webcam with usb-redirection (so through
usbdevfs), my userspace usb-redir code was getting a value of -1 in
iso_frame_desc[n].status, which according to Documentation/usb/error-codes.txt
is not a valid value.
The source of this -1 is the default case in xhci-ring.c:process_isoc_td()
adding a kprintf there showed the value of trb_comp_code to be COMP_TX_ERR
in this case, so this patch adds handling for that completion code to
process_isoc_td().
This was observed and tested with the following xhci controller:
1033:0194 NEC Corporation uPD720200 USB 3.0 Host Controller (rev 04)
Note: I also wonder if setting frame->status to -1 (-EPERM) is the best we can
do, but since I cannot come up with anything better I've left that as is.
This patch should be backported to kernels as old as 2.6.36, which contain the
commit 04e51901dd "USB: xHCI: Isochronous
transfer implementation".
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
This commit adds a bit-array to xhci bus_state for keeping track of
which ports are undergoing a resume transition. If any of the bits
are set when xhci_hub_status_data() is called, the routine will return
a non-zero value even if no ports have any status changes pending.
This will allow usbcore to handle races between root-hub suspend and
port wakeup.
This patch should be backported to kernels as old as 3.4, that contain
the commit 879d38e6bc "USB: fix race
between root-hub suspend and remote wakeup".
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: stable@vger.kernel.org
The caller is allowed to specify the GFP flags for these functions.
We should prefer their flags unless we have good reason. For
example, if we take a spin_lock ourselves we'd need to use
GFP_ATOMIC. But in this case it's safe to use the callers GFP
flags.
The callers all pass GFP_ATOMIC here, so this change doesn't affect
how the kernel behaves but we may add other callers later and this
is a cleanup.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
While we're at that, define IMAN bitfield to aid readability.
The interrupt enable bit should be set once on driver init, and we
shouldn't need to continually re-enable it. Commit c21599a3 introduced
a read of the irq_pending register, and that allows us to preserve the
state of the IE bit. Before that commit, we were blindly writing 0x3 to
the register.
This patch should be backported to kernels as old as 2.6.36, or ones
that contain the commit c21599a361 "USB:
xhci: Reduce reads and writes of interrupter registers".
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
When a urb is submitted to xHCI driver, check if queueing the urb will make
the enqueue pointer advance into dequeue seg and expand the ring if it
occurs. This is to guarantee the safety of ring expansion.
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: Paul Zimmerman <Paul.Zimmerman@synopsys.com>
If room_on_ring() check fails, try to expand the ring and check again.
When expand a ring, use a cached ring or allocate new segments, link
the original ring and the new ring or segments, update the original ring's
segment numbers and the last segment pointer.
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: Paul Zimmerman <Paul.Zimmerman@synopsys.com>
In the past, the room_on_ring() check was implemented by walking all over
the ring, which is wasteful and complicated.
Count the number of free TRBs instead. The free TRBs number should be
updated when enqueue/dequeue pointer is updated, or upon the completion
of a set dequeue pointer command.
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: Paul Zimmerman <Paul.Zimmerman@synopsys.com>
When allocate a ring, store its type - four transfer types for endpoint,
TYPE_STREAM for stream transfer, and TYPE_COMMAND/TYPE_EVENT for xHCI host.
This helps to get rid of three bool function parameters: link_trbs, isoc
and consumer.
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: Paul Zimmerman <Paul.Zimmerman@synopsys.com>
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: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB 3.0 hubs don't have a port suspend change bit (that bit is now
reserved). Instead, when a host-initiated resume finishes, the hub sets
the port link state change bit.
When a USB 3.0 device initiates remote wakeup, the parent hubs with
their upstream links in U3 will pass the LFPS up the chain. The first
hub that has an upstream link in U0 (which may be the roothub) will
reflect that LFPS back down the path to the device.
However, the parent hubs in the resumed path will not set their link
state change bit. Instead, the device that initiated the resume has to
send an asynchronous "Function Wake" Device Notification up to the host
controller. Therefore, we need a way to notify the USB core of a device
resume without going through the normal hub URB completion method.
First, make the xHCI roothub act like an external USB 3.0 hub and not
pass up the port link state change bit when a device-initiated resume
finishes. Introduce a new xHCI bit field, port_remote_wakeup, so that
we can tell the difference between a port coming out of the U3Exit state
(host-initiated resume) and the RExit state (ending state of
device-initiated resume).
Since the USB core can't tell whether a port on a hub has resumed by
looking at the Hub Status buffer, we need to introduce a bitfield,
wakeup_bits, that indicates which ports have resumed. When the xHCI
driver notices a port finishing a device-initiated resume, we call into
a new USB core function, usb_wakeup_notification(), that will set
the right bit in wakeup_bits, and kick khubd for that hub.
We also call usb_wakeup_notification() when the Function Wake Device
Notification is received by the xHCI driver. This covers the case where
the link between the roothub and the first-tier hub is in U0, and the
hub reflects the resume signaling back to the device without giving any
indication it has done so until the device sends the Function Wake
notification.
Change the code in khubd that handles the remote wakeup to look at the
state the USB core thinks the device is in, and handle the remote wakeup
if the port's wakeup bit is set.
This patch only takes care of the case where the device is attached
directly to the roothub, or the USB 3.0 hub that is attached to the root
hub is the device sending the Function Wake Device Notification (e.g.
because a new USB device was attached). The other cases will be covered
in a second patch.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
When the USB 3.0 hub support went in, I disabled selective suspend for
all external USB 3.0 hubs because they used a different mechanism to
enable remote wakeup. In fact, other USB 3.0 devices that could signal
remote wakeup would have been prevented from going into suspend because
they would have stalled the SetFeature Device Remote Wakeup request.
This patch adds support for the USB 3.0 way of enabling remote wake up
(with a SetFeature Function Suspend request), and enables selective
suspend for all hubs during hub_probe. It assumes that all USB 3.0 have
only one "function" as defined by the interface association descriptor,
which is true of all the USB 3.0 devices I've seen so far. FIXME if
that turns out to change later.
After a device signals a remote wakeup, it is supposed to send a Device
Notification packet to the host controller, signaling which function
sent the remote wakeup. The host can then put any other functions back
into function suspend. Since we don't have support for function suspend
(and no devices currently support it), we'll just assume the hub
function will resume the device properly when it received the port
status change notification, and simply ignore any device notification
events from the xHCI host controller.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
xHCI roothubs go through slightly different port state machines when
either a device initiates a remote wakeup and signals resume, or when
the host initiates a resume.
According to section 4.19.1.2.13 of the xHCI 1.0 spec, on host-initiated
resume, the xHC port state machine automatically goes through the U3Exit
state into the U0 state, setting the port link state change (PLC) bit in
the process.
When a device initiates resume, the xHCI port state machine goes into
the "Resume" state and sets the PLC bit. Then the xHCI driver writes U0
into the port link state register to transition the port to U0 from the
Resume state.
We can't be sure the device is actually in the U0 state until we receive
the next port status change event with the PLC bit set. We really don't
want khubd to be polling the roothub port status bits until the device
is really in U0.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: Andiry Xu <andiry.xu@amd.com>
When a TD length mismatch is found during isoc TRB enqueue, it directly
returns -EINVAL. However, isoc transfer is partially enqueued at this time,
and the ring should be cleared.
This should be backported to kernels as old as 2.6.36, which contain the
commit 522989a27c "xhci: Fix failed
enqueue in the middle of isoch TD."
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
The xHCI hub port code gets passed a zero-based port number by the USB
core. It then adds one to in order to find a device slot by port number
and device speed by calling xhci_find_slot_id_by_port. That function
clearly states it requires a one-based port number. The xHCI port
status change event handler was using a zero-based port number that it
got from find_faked_portnum_from_hw_portnum, not a one-based port
number. This lead to the doorbells never being rung for a device after
a resume, or worse, a different device with the same speed having its
doorbell rung (which could lead to bad power management in the xHCI host
controller).
This patch should be backported to kernels as old as 2.6.39.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: Andiry Xu <andiry.xu@amd.com>
Cc: stable@vger.kernel.org
Randy Dunlap points out that commit 9258c0b2 "xhci: Better debugging for
critical host errors." introduces some new build warnings on 32-bit
builds:
drivers/usb/host/xhci-ring.c:1936:3: warning: format '%016llx' expects type 'long long unsigned int', but argument 3 has type 'dma_addr_t'
drivers/usb/host/xhci-ring.c:1958:3: warning: format '%016llx' expects type 'long long unsigned int', but argument 3 has type 'dma_addr_t'
Cast the results of xhci_trb_virt_to_dma() from a dma_addr_t to an
unsigned long long.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: Randy Dunlap <rdunlap@xenotime.net>
When a host controller gives a bad event TRB, we should print out the
contents of the TRB as a warning so that users don't have to recompile
their kernel to get information about what went wrong. Also, print out
the event ring if they have xHCI debugging turned on, since previous
events can often explain what happened before the bad TRB occurred.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
With devices that can need up to 128 segments (with 64 TRBs per
segment), we can't afford to print out the entire endpoint ring every
time an URB is canceled. Instead, print the offset of the TRB, along
with device pathname and endpoint number.
Only print DMA addresses, since virtual addresses of internal structures
are not useful. Change the cancellation code to be more clear about
what steps of the cancellation it is in the process of doing (queueing
the request, handling the stop endpoint command, turning the TDs into
no-ops, or moving the dequeue pointers).
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
The code for toggling the cycle bits when the ring wraps around has
worked for years. The print statement alone is not enough to indicate
there's something wrong with that code. Now that full transfer tracing
has been ripped out, the print statement or lack thereof won't help
without context of where the enqueue pointer is.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Users can trace the submission of URBs through USBmon, so it makes no
sense to have duplicate debugging in the xHCI driver.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Remove verbose debugging about scatter-gather lists, as we haven't had
an issue with scatter gather list math for about a year now. The
debugging didn't help before, and just clutters up the log file when
trying to debug other issues.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Getting a short packet or a babble error is usually a recoverable error,
so stop scaring users with warnings in dmesg when xHCI debugging is turned
off.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
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: Clemens Ladisch <clemens@ladisch.de>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This pulls in the latest USB bugfixes and helps a few of the drivers
merge nicer in the future due to changes in both branches.
Signed-off-by: Greg 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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'usb-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (260 commits)
usb: renesas_usbhs: fixup inconsistent return from usbhs_pkt_push()
usb/isp1760: Allow to optionally trigger low-level chip reset via GPIOLIB.
USB: gadget: midi: memory leak in f_midi_bind_config()
USB: gadget: midi: fix range check in f_midi_out_open()
QE/FHCI: fixed the CONTROL bug
usb: renesas_usbhs: tidyup for smatch warnings
USB: Fix USB Kconfig dependency problem on 85xx/QoirQ platforms
EHCI: workaround for MosChip controller bug
usb: gadget: file_storage: fix race on unloading
USB: ftdi_sio.c: Use ftdi async_icount structure for TIOCMIWAIT, as in other drivers
USB: ftdi_sio.c:Fill MSR fields of the ftdi async_icount structure
USB: ftdi_sio.c: Fill LSR fields of the ftdi async_icount structure
USB: ftdi_sio.c:Fill TX field of the ftdi async_icount structure
USB: ftdi_sio.c: Fill the RX field of the ftdi async_icount structure
USB: ftdi_sio.c: Basic icount infrastructure for ftdi_sio
usb/isp1760: Let OF bindings depend on general CONFIG_OF instead of PPC_OF .
USB: ftdi_sio: Support TI/Luminary Micro Stellaris BD-ICDI Board
USB: Fix runtime wakeup on OHCI
xHCI/USB: Make xHCI driver have a BOS descriptor.
usb: gadget: add new usb gadget for ACM and mass storage
...
Setting the chain (CH) bit in the link TRB of isochronous transfer rings
is required by AMD 0.96 xHCI host controller to successfully transverse
multi-TRB TD that span through different memory segments.
When a Missed Service Error event occurs, if the chain bit is not set in
the link TRB and the host skips TDs which just across a link TRB, the
host may falsely recognize the link TRB as a normal TRB. You can see
this may cause big trouble - the host does not jump to the right address
which is pointed by the link TRB, but continue fetching the memory which
is after the link TRB address, which may not even belong to the host,
and the result cannot be predicted.
This causes some big problems. Without the former patch I sent: "xHCI:
prevent infinite loop when processing MSE event", the system may hang.
With that patch applied, system does not hang, but the host still access
wrong memory address and isoc transfer will fail. With this patch,
isochronous transfer works as expected.
This patch should be applied to kernels as old as 2.6.36, which was when
the first isochronous support was added for the xHCI host controller.
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When the link state changes, xHC will report a port status change event
and set the PORT_PLC bit, for both USB3 and USB2 root hub ports.
The PLC will be cleared by usbcore for USB3 root hub ports, but not for
USB2 ports, because they do not report USB_PORT_STAT_C_LINK_STATE in
wPortChange.
Clear it for USB2 root hub ports in handle_port_status().
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When a xHC host is unable to handle isochronous transfer in the
interval, it reports a Missed Service Error event and skips some tds.
Currently xhci driver handles MSE event in the following ways:
1. When encounter a MSE event, set ep->skip flag, update event ring
dequeue pointer and return.
2. When encounter the next event on this ep, the driver will run the
do-while loop, fetch td from ep's td_list to find the td
corresponding to this event. All tds missed are marked as short
transfer(-EXDEV).
The do-while loop will end in two ways:
1. If the td pointed by the event trb is found;
2. If the ep ring's td_list is empty.
However, if a buggy HW reports some unpredicted event (for example, an
overrun event following a MSE event while the ep ring is actually not
empty), the driver will never find the td, and it will loop until the
td_list is empty.
Unfortunately, the spinlock is dropped when give back a urb in the
do-while loop. During the spinlock released period, the class driver
may still submit urbs and add tds to the td_list. This may cause
disaster, since the td_list will never be empty and the loop never ends,
and the system hangs.
To fix this, count the number of TDs on the ep ring before skipping TDs,
and quit the loop when skipped that number of tds. This guarantees the
do-while loop will end after certain number of cycles, and driver will
not be trapped in an infinite loop.
Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that the xHCI driver always return a status value of zero for isochronous
URBs, when the last TD of an isochronous URB is short, the local variable
"status" stays set to -EINPROGRESS. When xHCI driver debugging is turned on,
this causes the log file to fill with messages like this:
[ 38.859282] xhci_hcd 0000:00:14.0: Giveback URB ffff88013ad47800, len = 1408, expected = 580, status = -115
Don't print out the status of an URB for isochronous URBs.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Now ${LINUX}/drivers/usb/* can use usb_endpoint_maxp(desc) to get maximum packet size
instead of le16_to_cpu(desc->wMaxPacketSize).
This patch fix it up
Cc: Armin Fuerst <fuerst@in.tum.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Johannes Erdfelt <johannes@erdfelt.com>
Cc: Vojtech Pavlik <vojtech@suse.cz>
Cc: Oliver Neukum <oliver@neukum.name>
Cc: David Kubicek <dave@awk.cz>
Cc: Johan Hovold <jhovold@gmail.com>
Cc: Brad Hards <bhards@bigpond.net.au>
Acked-by: Felipe Balbi <balbi@ti.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Dahlmann <dahlmann.thomas@arcor.de>
Cc: David Brownell <david-b@pacbell.net>
Cc: David Lopo <dlopo@chipidea.mips.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Michal Nazarewicz <m.nazarewicz@samsung.com>
Cc: Xie Xiaobo <X.Xie@freescale.com>
Cc: Li Yang <leoli@freescale.com>
Cc: Jiang Bo <tanya.jiang@freescale.com>
Cc: Yuan-hsin Chen <yhchen@faraday-tech.com>
Cc: Darius Augulis <augulis.darius@gmail.com>
Cc: Xiaochen Shen <xiaochen.shen@intel.com>
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: OKI SEMICONDUCTOR, <toshiharu-linux@dsn.okisemi.com>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: Ben Dooks <ben@simtec.co.uk>
Cc: Thomas Abraham <thomas.ab@samsung.com>
Cc: Herbert Pötzl <herbert@13thfloor.at>
Cc: Arnaud Patard <arnaud.patard@rtp-net.org>
Cc: Roman Weissgaerber <weissg@vienna.at>
Acked-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Tony Olech <tony.olech@elandigitalsystems.com>
Cc: Florian Floe Echtler <echtler@fs.tum.de>
Cc: Christian Lucht <lucht@codemercs.com>
Cc: Juergen Stuber <starblue@sourceforge.net>
Cc: Georges Toth <g.toth@e-biz.lu>
Cc: Bill Ryder <bryder@sgi.com>
Cc: Kuba Ober <kuba@mareimbrium.org>
Cc: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
For a long time, the xHCI driver has had this note:
/* FIXME: Ignoring zero-length packets, can those happen? */
It turns out that, yes, there are drivers that need to queue zero-length
transfers for isochronous OUT transfers. Without this patch, users will
see kernel hang messages when a driver attempts to enqueue an isochronous
URB with a zero length transfer (because count_isoc_trbs_needed will return
zero for that TD, xhci_td->last_trb will never be set, and updating the
dequeue pointer will cause an infinite loop).
Matěj ran into this issue when using an NI Audio4DJ USB soundcard
with the snd-usb-caiaq driver. See
https://bugzilla.kernel.org/show_bug.cgi?id=40702
Fix count_isoc_trbs_needed() to return 1 for zero-length transfers (thanks
Alan on the math help). Update the various TRB field calculations to deal
with zero-length transfers. We're still transferring one packet with a
zero-length data payload, so the total_packet_count should be 1. The
Transfer Burst Count (TBC) and Transfer Last Burst Packet Count (TLBPC)
fields should be set to zero.
This patch should be backported to kernels as old as 2.6.36.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: Matěj Laitl <matej@laitl.cz>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: stable@kernel.org
When a driver tries to cancel an URB, and the host controller is dying,
xhci_urb_dequeue will giveback the URB without removing the xhci_tds
that comprise that URB from the td_list or the cancelled_td_list. This
can cause a race condition between the driver calling URB dequeue and
the stop endpoint command watchdog timer.
If the timer fires on a dying host, and a driver attempts to resubmit
while the watchdog timer has dropped the xhci->lock to giveback a
cancelled URB, URBs may be given back by the xhci_urb_dequeue() function.
At that point, the URB's priv pointer will be freed and set to NULL, but
the TDs will remain on the td_list. This will cause an oops in
xhci_giveback_urb_in_irq() when the watchdog timer attempts to loop
through the endpoints' td_lists, giving back killed URBs.
Make sure that xhci_urb_dequeue() removes TDs from the TD lists and
canceled TD lists before it gives back the URB.
This patch should be backported to kernels as old as 2.6.36.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Andiry Xu <andiry.xu@amd.com>
Cc: stable@kernel.org
When an isochronous transfer is enqueued, xhci_queue_isoc_tx_prepare()
will ensure that there is enough room on the transfer rings for all of the
isochronous TDs for that URB. However, when xhci_queue_isoc_tx() is
enqueueing individual isoc TDs, the prepare_transfer() function can fail
if the endpoint state has changed to disabled, error, or some other
unknown state.
With the current code, if Nth TD (not the first TD) fails, the ring is
left in a sorry state. The partially enqueued TDs are left on the ring,
and the first TRB of the TD is not given back to the hardware. The
enqueue pointer is left on the TRB after the last successfully enqueued
TD. This means the ring is basically useless. Any new transfers will be
enqueued after the failed TDs, which the hardware will never read because
the cycle bit indicates it does not own them. The ring will fill up with
untransferred TDs, and the endpoint will be basically unusable.
The untransferred TDs will also remain on the TD list. Since the td_list
is a FIFO, this basically means the ring handler will be waiting on TDs
that will never be completed (or worse, dereference memory that doesn't
exist any more).
Change the code to clean up the isochronous ring after a failed transfer.
If the first TD failed, simply return and allow the xhci_urb_enqueue
function to free the urb_priv. If the Nth TD failed, first remove the TDs
from the td_list. Then convert the TRBs that were enqueued into No-op
TRBs. Make sure to flip the cycle bit on all enqueued TRBs (including any
link TRBs in the middle or between TDs), but leave the cycle bit of the
first TRB (which will show software-owned) intact. Then move the ring
enqueue pointer back to the first TRB and make sure to change the
xhci_ring's cycle state to what is appropriate for that ring segment.
This ensures that the No-op TRBs will be overwritten by subsequent TDs,
and the hardware will not start executing random TRBs because the cycle
bit was left as hardware-owned.
This bug is unlikely to be hit, but it was something I noticed while
tracking down the watchdog timer issue. I verified that the fix works by
injecting some errors on the 250th isochronous URB queued, although I
could not verify that the ring is in the correct state because uvcvideo
refused to talk to the device after the first usb_submit_urb() failed.
Ring debugging shows that the ring looks correct, however.
This patch should be backported to kernels as old as 2.6.36.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Andiry Xu <andiry.xu@amd.com>
Cc: stable@kernel.org
When the isochronous transfer support was introduced, and the xHCI driver
switched to using urb->hcpriv to store an "urb_priv" pointer, a couple of
memory leaks were introduced into the URB enqueue function in its error
handling paths.
xhci_urb_enqueue allocates urb_priv, but it doesn't free it if changing
the control endpoint's max packet size fails or the bulk endpoint is in
the middle of allocating or deallocating streams.
xhci_urb_enqueue also doesn't free urb_priv if any of the four endpoint
types' enqueue functions fail. Instead, it expects those functions to
free urb_priv if an error occurs. However, the bulk, control, and
interrupt enqueue functions do not free urb_priv if the endpoint ring is
NULL. It will, however, get freed if prepare_transfer() fails in those
enqueue functions.
Several of the error paths in the isochronous endpoint enqueue function
also fail to free it. xhci_queue_isoc_tx_prepare() doesn't free urb_priv
if prepare_ring() indicates there is not enough room for all the
isochronous TDs in this URB. If individual isochronous TDs fail to be
queued (perhaps due to an endpoint state change), urb_priv is also leaked.
This argues that the freeing of urb_priv should be done in the function
that allocated it, xhci_urb_enqueue.
This patch looks rather ugly, but refactoring the code will have to wait
because this patch needs to be backported to stable kernels.
This patch should be backported to kernels as old as 2.6.36.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Andiry Xu <andiry.xu@amd.com>
Cc: stable@kernel.org
* 'usb-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (115 commits)
EHCI: fix direction handling for interrupt data toggles
USB: serial: add IDs for WinChipHead USB->RS232 adapter
USB: OHCI: fix another regression for NVIDIA controllers
usb: gadget: m66592-udc: add pullup function
usb: gadget: m66592-udc: add function for external controller
usb: gadget: r8a66597-udc: add pullup function
usb: renesas_usbhs: support multi driver
usb: renesas_usbhs: inaccessible pipe is not an error
usb: renesas_usbhs: care buff alignment when dma handler
USB: PL2303: correctly handle baudrates above 115200
usb: r8a66597-hcd: fixup USB_PORT_STAT_C_SUSPEND shift
usb: renesas_usbhs: compile/config are rescued
usb: renesas_usbhs: fixup comment-out
usb: update email address in ohci-sh and r8a66597-hcd
usb: r8a66597-hcd: add function for external controller
EHCI: only power off port if over-current is active
USB: mon: Allow to use usbmon without debugfs
USB: EHCI: go back to using the system clock for QH unlinks
ehci: add pci quirk for Ordissimo and RM Slate 100 too
ehci: refactor pci quirk to use standard dmi_check_system method
...
Fix up trivial conflicts in Documentation/feature-removal-schedule.txt
When the xHCI driver encounters a Missed Service Interval event for an
isochronous endpoint ring, it means the host controller skipped over
one or more isochronous TDs. For TD that is skipped, skip_isoc_td() is
called. This sets the frame descriptor status to -EXDEV, and also sets
the value stored in the int pointed to by status to -EXDEV.
If the isochronous TD happens to be the last TD in an URB,
handle_tx_event() will use the status variable to give back the URB to
the USB core. That means drivers will see urb->status as -EXDEV.
It turns out that EHCI, UHCI, and OHCI always set urb->status to zero for
an isochronous urb, regardless of what the frame status is. See
itd_complete() in ehci-sched.c:
} else {
/* URB was too late */
desc->status = -EXDEV;
}
}
/* handle completion now? */
if (likely ((urb_index + 1) != urb->number_of_packets))
goto done;
/* ASSERT: it's really the last itd for this urb
list_for_each_entry (itd, &stream->td_list, itd_list)
BUG_ON (itd->urb == urb);
*/
/* give urb back to the driver; completion often (re)submits */
dev = urb->dev;
ehci_urb_done(ehci, urb, 0);
ehci_urb_done() completes the URB with the status of the third argument, which
is always zero in this case.
It turns out that many USB webcam drivers, such as uvcvideo, cannot
handle urb->status set to a non-zero value. They will not resubmit
their isochronous URBs in that case, and userspace will see a frozen
video.
Change the xHCI driver to be consistent with the EHCI and UHCI driver,
and always set urb->status to 0 for isochronous URBs.
This patch should be backported to kernels as old as 2.6.36
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: "Xu, Andiry" <Andiry.Xu@amd.com>
Cc: stable@kernel.org
It is one new TRB Completion Code for the xHCI spec v1.0.
Asserted if the xHC detects a problem with a device that does not allow it to
be successfully accessed, e.g. due to a device compliance or compatibility
problem. This error may be returned by any command or transfer, and is fatal
as far as the Slot is concerned. Return -EPROTO by urb->status or frame->status
of ISOC for transfer case. And return -ENODEV for configure endpoint command,
evaluate context command and address device command if there is an incompatible
Device Error. The error codes will be sent back to the USB core to decide how
to do. It's unnecessary for other commands because after the three commands run
successfully means that the device has been accepted.
Signed-off-by: Alex He <alex.he@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
FSE shall occur on the TD natural boundary. The software ep_ring dequeue pointer
exceed the hardware ep_ring dequeue pointer in these cases of Table-3. As a
result, the event_trb(pointed by hardware dequeue pointer) of the FSE can't be
found in the current TD(pointed by software dequeue pointer). What should we do
is to figured out the FSE case and skip over it.
Signed-off-by: Alex He <alex.he@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Some of the recently-added cpu_to_leXX and leXX_to_cpu made things somewhat
messy; this patch neatens some of these areas, removing unnecessary casts
in those parts also. In some places (where Y & Z are constants) a
comparison of (leXX_to_cpu(X) & Y) == Z has been replaced with
(X & cpu_to_leXX(Y)) == cpu_to_leXX(Z). The endian reversal of the
constants should wash out at compile time.
Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Commit 926008c938 "USB: xhci: simplify logic
of skipping missed isoc TDs" added a small endian bug. This patch
fixes skip_isoc_td() to read the DMA pointer correctly.
Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
The Panther Point chipset has an xHCI host controller that has a limit to
the number of active endpoints it can handle. Ideally, it would signal
that it can't handle anymore endpoints by returning a Resource Error for
the Configure Endpoint command, but they don't. Instead it needs software
to keep track of the number of active endpoints, across configure endpoint
commands, reset device commands, disable slot commands, and address device
commands.
Add a new endpoint context counter, xhci_hcd->num_active_eps, and use it
to track the number of endpoints the xHC has active. This gets a little
tricky, because commands to change the number of active endpoints can
fail. This patch adds a new xHCI quirk for these Intel hosts, and the new
code should not have any effect on other xHCI host controllers.
Fail a new device allocation if we don't have room for the new default
control endpoint. Use the endpoint ring pointers to determine what
endpoints were active before a Reset Device command or a Disable Slot
command, and drop those once the command completes.
Fail a configure endpoint command if it would add too many new endpoints.
We have to be a bit over zealous here, and only count the number of new
endpoints to be added, without subtracting the number of dropped
endpoints. That's because a second configure endpoint command for a
different device could sneak in before we know if the first command is
completed. If the first command dropped resources, the host controller
fails the command for some reason, and we're nearing the limit of
endpoints, we could end up oversubscribing the host.
To fix this race condition, when evaluating whether a configure endpoint
command will fix in our bandwidth budget, only add the new endpoints to
xhci->num_active_eps, and don't subtract the dropped endpoints. Ignore
changed endpoints (ones that are dropped and then re-added), as that
shouldn't effect the host's endpoint resources. When the configure
endpoint command completes, subtract off the dropped endpoints.
This may mean some configuration changes may temporarily fail, but it's
always better to under-subscribe than over-subscribe resources.
(Originally my plan had been to push the resource allocation down into the
ring allocation functions. However, that would cause us to allocate
unnecessary resources when endpoints were changed, because the xHCI driver
allocates a new ring for the changed endpoint, and only deletes the old
ring once the Configure Endpoint command succeeds. A further complication
would have been dealing with the per-device endpoint ring cache.)
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
The xHCI host controller in the Panther Point chipset sometimes produces
spurious events on the event ring. If it receives a short packet, it
first puts a Transfer Event with a short transfer completion code on the
event ring. Then it puts a Transfer Event with a successful completion
code on the ring for the same TD. The xHCI driver correctly processes the
short transfer completion code, gives the URB back to the driver, and then
prints a warning in dmesg about the spurious event. These warning
messages really fill up dmesg when an HD webcam is plugged into xHCI.
This spurious successful event behavior isn't technically disallowed by
the xHCI specification, so make the xHCI driver just ignore the spurious
completion event.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Unsurprisingly, URBs get submitted and completed a lot in the xHCI
driver. If we have to print 10 lines of debug for every URB submitted
or completed, then that can cause the whole system to stay in the
interrupt handler too long, and can cause Missed Service completion
codes for isochronous transfers.
Cut down the debugging in the URB submission and completion paths:
- Don't squawk about successful transfers, only unsuccessful ones.
- Only print the number of bytes transferred if this was a short
transfer.
- Don't print the endpoint index for successful transfers (will add
more debug to failed transfers to show endpoint index there later).
- Stop printing MMIO writes. This debugging shows up when the endpoint
doorbell is rung a to start a transfer (basically for every URB).
- Don't print out the ring enqueue and dequeue pointers
- Stop printing when we're pointing to a link TRB.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Stop printing out the event ring dequeue pointer and status register in
the operational register set. The host will report an OK status 99% of
the time the interrupt handler is called, and usually when it's really
hosed, a host controller won't even call the interrupt handler. So the
line is really useless.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Remove unnecessary debugging from the xHCI driver. We don't need to
know what function we're calling or returning from. Now I know how to
use markup-oops.pl to de-mystify stack dumps of crashes.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
When an URB is cancelled, the xHCI driver issues a Stop Endpoint command
so that it can manipulate the ring and remove the transfer. The xHC
hardware then places a transfer event with the completion code "Stopped"
or "Stopped Invalid" to let the driver know what TD it was in the middle
of processing. This TD and TRB is stored in ep->stopped_td and
ep->stopped_trb. These pointers are also used in handling stalled
endpoints.
By design, the Stop Endpoint command can race with URB completion. By
the time the Stop Endpoint command is handled, the URBs to be cancelled
may have been given back to the driver. Unfortunately, the stopped_td
and stopped_trb pointers were not getting cleared in this case.
The USB core unconditionally tries to reset the toggle bits on any
endpoints when a new alternate interface setting is installed. When the
xHCI driver saw that ep->stopped_td was still set from the Stop Endpoint
command, xhci_reset_endpoint assumed the endpoint was actually stalled,
and attempted to clean up the endpoint rings. This would manifest
itself in a failed Reset Endpoint command and failed Set TR dequeue
Pointer command after a successful Configure Endpoint command. It may
have also been causing driver oops when the stopped_td was accessed.
This patch should be backported to stable kernels since 2.6.31. Before
2.6.33, stopped_td was found in the xhci_endpoint_ring, not the
xhci_virt_ep.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
When the xHCI driver attempts to cancel a transfer, it issues a Stop
Endpoint command and waits for the host controller to indicate which TRB
it was in the middle of processing. The host will put an event TRB with
completion code COMP_STOP on the event ring if it stops on a control
transfer TRB (or other types of transfer TRBs). The ring handling code
is supposed to set ep->stopped_trb to the TRB that the host stopped on
when this happens.
Unfortunately, there is a long-standing bug in the control transfer
completion code. It doesn't actually check to see if COMP_STOP is set
before attempting to process the transfer based on which part of the
control TD completed. So when we get an event on the data phase of the
control TRB with COMP_STOP set, it thinks it's a normal completion of
the transfer and doesn't set ep->stopped_td or ep->stopped_trb.
When the ring handling code goes on to process the completion of the Stop
Endpoint command, it sees that ep->stopped_trb is not a part of the TD
it's trying to cancel. It thinks the hardware has its enqueue pointer
somewhere further up in the ring, and thinks it's safe to turn the control
TRBs into no-op TRBs. Since the hardware was in the middle of the control
TRBs to be cancelled, the proper software behavior is to issue a Set TR
dequeue pointer command.
It turns out that the NEC host controllers can handle active TRBs being
set to no-op TRBs after a stop endpoint command, but other host
controllers have issues with this out-of-spec software behavior. Fix this
behavior.
This patch should be backported to kernels as far back as 2.6.31, but it
may be a bit challenging, since process_ctrl_td() was introduced in some
refactoring done in 2.6.36, and some endian-safe patches added in 2.6.40
that touch the same lines.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: stable@kernel.org