Commit Graph

513 Commits

Author SHA1 Message Date
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Sriharsha Allenki
3c6f8cb92c usb: xhci: Fix NULL pointer dereference when enqueuing trbs from urb sg list
On platforms with IOMMU enabled, multiple SGs can be coalesced into one
by the IOMMU driver. In that case the SG list processing as part of the
completion of a urb on a bulk endpoint can result into a NULL pointer
dereference with the below stack dump.

<6> Unable to handle kernel NULL pointer dereference at virtual address 0000000c
<6> pgd = c0004000
<6> [0000000c] *pgd=00000000
<6> Internal error: Oops: 5 [#1] PREEMPT SMP ARM
<2> PC is at xhci_queue_bulk_tx+0x454/0x80c
<2> LR is at xhci_queue_bulk_tx+0x44c/0x80c
<2> pc : [<c08907c4>]    lr : [<c08907bc>]    psr: 000000d3
<2> sp : ca337c80  ip : 00000000  fp : ffffffff
<2> r10: 00000000  r9 : 50037000  r8 : 00004000
<2> r7 : 00000000  r6 : 00004000  r5 : 00000000  r4 : 00000000
<2> r3 : 00000000  r2 : 00000082  r1 : c2c1a200  r0 : 00000000
<2> Flags: nzcv  IRQs off  FIQs off  Mode SVC_32  ISA ARM  Segment none
<2> Control: 10c0383d  Table: b412c06a  DAC: 00000051
<6> Process usb-storage (pid: 5961, stack limit = 0xca336210)
<snip>
<2> [<c08907c4>] (xhci_queue_bulk_tx)
<2> [<c0881b3c>] (xhci_urb_enqueue)
<2> [<c0831068>] (usb_hcd_submit_urb)
<2> [<c08350b4>] (usb_sg_wait)
<2> [<c089f384>] (usb_stor_bulk_transfer_sglist)
<2> [<c089f2c0>] (usb_stor_bulk_srb)
<2> [<c089fe38>] (usb_stor_Bulk_transport)
<2> [<c089f468>] (usb_stor_invoke_transport)
<2> [<c08a11b4>] (usb_stor_control_thread)
<2> [<c014a534>] (kthread)

The above NULL pointer dereference is the result of block_len and the
sent_len set to zero after the first SG of the list when IOMMU driver
is enabled. Because of this the loop of processing the SGs has run
more than num_sgs which resulted in a sg_next on the last SG of the
list which has SG_END set.

Fix this by check for the sg before any attributes of the sg are
accessed.

[modified reason for null pointer dereference in commit message subject -Mathias]
Fixes: f9c589e142 ("xhci: TD-fragment, align the unsplittable case with a bounce buffer")
Cc: stable@vger.kernel.org
Signed-off-by: Sriharsha Allenki <sallenki@codeaurora.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200514110432.25564-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14 13:44:37 +02:00
Mathias Nyman
8f97250c21 xhci: Don't clear hub TT buffer on ep0 protocol stall
The default control endpoint ep0 can return a STALL indicating the
device does not support the control transfer requests. This is called
a protocol stall and does not halt the endpoint.

xHC behaves a bit different. Its internal endpoint state will always
be halted on any stall, even if the device side of the endpiont is not
halted. So we do need to issue the reset endpoint command to clear the
xHC host intenal endpoint halt state, but should not request the HS hub
to clear the TT buffer unless device side of endpoint is halted.

Clearing the hub TT buffer at protocol stall caused ep0 to become
unresponsive for some FS/LS devices behind HS hubs, and class drivers
failed to set the interface due to timeout:

usb 1-2.1: 1:1: usb_set_interface failed (-110)

Fixes: ef513be0a9 ("usb: xhci: Add Clear_TT_Buffer")
Cc: <stable@vger.kernel.org> # v5.3
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200421140822.28233-4-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-21 16:27:38 +02:00
Mathias Nyman
93ceaa808e xhci: Fix handling halted endpoint even if endpoint ring appears empty
If a class driver cancels its only URB then the endpoint ring buffer will
appear empty to the xhci driver. xHC hardware may still process cached
TRBs, and complete with a STALL, halting the endpoint.

This halted endpoint was not handled correctly by xhci driver as events on
empty rings were all assumed to be spurious events.
xhci driver refused to restart the ring with EP_HALTED flag set, so class
driver was never informed the endpoint halted even if it queued new URBs.

The host side of the endpoint needs to be reset, and dequeue pointer should
be moved in order to clear the cached TRBs and resetart the endpoint.

Small adjustments in finding the new dequeue pointer are needed to support
the case of stall on an empty ring and unknown current TD.

Cc: <stable@vger.kernel.org>
cc: Jeremy Compostella <jeremy.compostella@intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200421140822.28233-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-21 16:27:38 +02:00
Kai-Heng Feng
0200b9f790 xhci: Wait until link state trainsits to U0 after setting USB_SS_PORT_LS_U0
Like U3 case, xHCI spec doesn't specify the upper bound of U0 transition
time. The 20ms is not enough for some devices.

Intead of polling PLS or PLC, we can facilitate the port change event to
know that the link transits to U0 is completed.

While at it, also separate U0 and U3 case to make the code cleaner.

[variable rename to u3exit, and skip completion for usb2 ports -Mathias ]
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200312144517.1593-8-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 17:34:49 +01:00
Mathias Nyman
9c1aa36efd xhci: Show host status when watchdog triggers and host is assumed dead.
Additional debugging to show xHC USBSTS register when stop endpoint
command watchdog triggers and host is assumed dead.

useful to know the current status before the controller is stopped by
the xhci driver and everything is released and freed.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200312144517.1593-4-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 17:34:48 +01:00
Mathias Nyman
76eac5d21a xhci: Add a separate debug message for split transaction errors.
Don't show the same error message for transaction errors and split
transaction errors. It's very confusing while debugging.

Transaction errors are often due to electrical interference.
Split transaction errors are about xHC not being able to
schedule start and complete split transactions needed to address
low- and full-speed devices behind high-speed hubs.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200312144517.1593-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 17:34:48 +01:00
Mathias Nyman
7ff1116280 xhci: handle some XHCI_TRUST_TX_LENGTH quirks cases as default behaviour.
xhci driver claims it needs XHCI_TRUST_TX_LENGTH quirk for both
Broadcom/Cavium and a Renesas xHC controllers.

The quirk was inteded for handling false "success" complete event for
transfers that had data left untransferred.
These transfers should complete with "short packet" events instead.

In these two new cases the false "success" completion is reported
after a "short packet" if the TD consists of several TRBs.
xHCI specs 4.10.1.1.2 say remaining TRBs should report "short packet"
as well after the first short packet in a TD, but this issue seems so
common it doesn't make sense to add the quirk for all vendors.

Turn these events into short packets automatically instead.

This gets rid of the  "The WARN Successful completion on short TX for
slot 1 ep 1: needs XHCI_TRUST_TX_LENGTH quirk" warning in many cases.

Cc: <stable@vger.kernel.org>
Reported-by: Eli Billauer <eli.billauer@gmail.com>
Reported-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Eli Billauer <eli.billauer@gmail.com>
Tested-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20191211142007.8847-6-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-11 15:32:19 +01:00
Mathias Nyman
057d476fff xhci: fix USB3 device initiated resume race with roothub autosuspend
A race in xhci USB3 remote wake handling may force device back to suspend
after it initiated resume siganaling, causing a missed resume event or warm
reset of device.

When a USB3 link completes resume signaling and goes to enabled (UO)
state a interrupt is issued and the interrupt handler will clear the
bus_state->port_remote_wakeup resume flag, allowing bus suspend.

If the USB3 roothub thread just finished reading port status before
the interrupt, finding ports still in suspended (U3) state, but hasn't
yet started suspending the hub, then the xhci interrupt handler will clear
the flag that prevented roothub suspend and allow bus to suspend, forcing
all port links back to suspended (U3) state.

Example case:
usb_runtime_suspend() # because all ports still show suspended U3
  usb_suspend_both()
    hub_suspend();   # successful as hub->wakeup_bits not set yet
==> INTERRUPT
xhci_irq()
  handle_port_status()
    clear bus_state->port_remote_wakeup
    usb_wakeup_notification()
      sets hub->wakeup_bits;
        kick_hub_wq()
<== END INTERRUPT
      hcd_bus_suspend()
        xhci_bus_suspend() # success as port_remote_wakeup bits cleared

Fix this by increasing roothub usage count during port resume to prevent
roothub autosuspend, and by making sure bus_state->port_remote_wakeup
flag is only cleared after resume completion is visible, i.e.
after xhci roothub returned U0 or other non-U3 link state link on a
get port status request.

Issue rootcaused by Chiasheng Lee

Cc: <stable@vger.kernel.org>
Cc: Lee, Hou-hsun <hou-hsun.lee@intel.com>
Reported-by: Lee, Chiasheng <chiasheng.lee@intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20191211142007.8847-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-11 15:32:17 +01:00
Suwan Kim
36dc01657b usb: host: xhci: Support running urb giveback in tasklet context
Patch "USB: HCD: support giveback of URB in tasklet context"[1]
introduced giveback of urb in tasklet context. [1] This patch was
applied to ehci but not xhci. [2] This patch significantly reduces
the hard irq time of xhci. Especially for uvc driver, the hard irq
including the uvc completion function runs quite long but applying
this patch reduces the hard irq time of xhci.

I have tested four SS devices to check if performance degradation
occurs when urb completion functions run in the tasklet context.

As a result of the test, all devices works well and shows very
similar performance with the upstream kernel. Moreover, usb ethernet
adapter show better performance than the upstream kernel about 5% for
RX and 2% for TX. Four SS devices is as follows.

SS devices for test

1. WD My Passport 2TB (external hard drive)
2. Sandisk Ultra Flair USB 3.0 32GB
3. Logitech Brio webcam
4. Iptime 1gigabit ethernet adapter (Mediatek RTL8153)

Test description

1. Mass storage (hard drive) performance test
- run below command 10 times and compute the average performance

    dd if=/dev/sdN iflag=direct of=/dev/null bs=1G count=1

2. Mass storage (flash memory) performance test
- run below command 10 times and compute the average performance

    dd if=/dev/sdN iflag=direct of=/dev/null bs=1G count=1

3. Webcam streaming performance test
- run simple capture program and get the average frame rate per second
- capture 1500 frames
- program link

    https://github.com/asfaca/Webcam-performance-analyzing-tool

- video resolution : 4096 X 2160 (4K) at 30 or 24 fps
- device (Logitech Brio) spec url for the highest resolution and fps

    https://support.logitech.com/en_gb/product/brio-stream/specs

4. USB Ethernet adapter performance test
- directly connect two linux machines with ethernet cable
- run pktgen of linux kernel and send 1500 bytes packets
- run vnstat to measure the network bandwidth for 180 seconds

Test machine

- CPU : Intel i5-7600 @ 3.5GHz

Test results

1. Mass storage (hard drive) performance test

            WD My Passport 2TB (external hard drive)
--------------------------------------------------------------------
    xhci without tasklet        |          xhci with tasklet
--------------------------------------------------------------------
         103.667MB/s            |            103.692MB/s
--------------------------------------------------------------------

2. Mass storage (flash memory) performance test

               Sandisk Ultra Flair USB 3.0 32GB
--------------------------------------------------------------------
    xhci without tasklet        |          xhci with tasklet
--------------------------------------------------------------------
         129.727MB/s            |            130.2MB/s
--------------------------------------------------------------------

3. Webcam streaming performance test

                     Logitech Brio webcam
--------------------------------------------------------------------
    xhci without tasklet        |          xhci with tasklet
--------------------------------------------------------------------
          26.4451 fps           |            26.3949 fps
--------------------------------------------------------------------

4. USB Ethernet adapter performance test

      Iptime 1gigabit ethernet adapter (Mediatek RTL8153)
--------------------------------------------------------------------
    xhci without tasklet        |          xhci with tasklet
--------------------------------------------------------------------
RX      933.86 Mbit/s           |            983.86 Mbit/s
--------------------------------------------------------------------
TX      830.18 Mbit/s           |            882.75 Mbit/s
--------------------------------------------------------------------

[1], https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=94dfd7edfd5c9b605caf7b562de7a813d216e011
[2], https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=428aac8a81058e2303677a8fbf26670229e51d3a

Signed-off-by: Suwan Kim <suwan.kim027@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/1573836603-10871-4-git-send-email-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-16 10:26:06 +01:00
Mathias Nyman
58b9d71a0f xhci: Add tracing for xhci doorbell register writes
Trace when a register in the doorbell array is written,
both for host controller command doorbell and device doorbells,
including for which endpoint and stream

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/1573836603-10871-3-git-send-email-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-16 10:26:05 +01:00
Peter Chen
dc0ffbea57 usb: host: xhci: update event ring dequeue pointer on purpose
On some situations, the software handles TRB events slower
than adding TRBs, then xhci_handle_event can't return zero
long time, the xHC will consider the event ring is full,
and trigger "Event Ring Full" error, but in fact, the software
has already finished lots of events, just no chance to
update ERDP (event ring dequeue pointer).

In this commit, we force update ERDP if half of TRBS_PER_SEGMENT
events have handled to avoid "Event Ring Full" error.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/1573836603-10871-2-git-send-email-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-16 10:26:05 +01:00
Samuel Holland
bfa3dbb343 usb: xhci: fix Immediate Data Transfer endianness
The arguments to queue_trb are always byteswapped to LE for placement in
the ring, but this should not happen in the case of immediate data; the
bytes copied out of transfer_buffer are already in the correct order.
Add a complementary byteswap so the bytes end up in the ring correctly.

This was observed on BE ppc64 with a "Texas Instruments TUSB73x0
SuperSpeed USB 3.0 xHCI Host Controller [104c:8241]" as a ch341
usb-serial adapter ("1a86:7523 QinHeng Electronics HL-340 USB-Serial
adapter") always transmitting the same character (generally NUL) over
the serial link regardless of the key pressed.

Cc: <stable@vger.kernel.org> # 5.2+
Fixes: 33e39350eb ("usb: xhci: add Immediate Data Transfer support")
Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/1572013829-14044-3-git-send-email-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-28 17:47:07 +01:00
Mathias Nyman
c03101ff4f xhci: Fix false warning message about wrong bounce buffer write length
The check printing out the "WARN Wrong bounce buffer write length:"
uses incorrect values when comparing bytes written from scatterlist
to bounce buffer. Actual copied lengths are fine.

The used seg->bounce_len will be set to equal new_buf_len a few lines later
in the code, but is incorrect when doing the comparison.

The patch which added this false warning was backported to 4.8+ kernels
so this should be backported as far as well.

Cc: <stable@vger.kernel.org> # v4.8+
Fixes: 597c56e372 ("xhci: update bounce buffer with correct sg num")
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/1570190373-30684-2-git-send-email-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-04 14:32:10 +02:00
Greg Kroah-Hartman
58ee01007c Merge 5.2-rc6 into usb-next
We need the USB fixes in here too.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-23 09:21:15 +02:00
Mathias Nyman
b8c3b71808 usb: xhci: Don't try to recover an endpoint if port is in error state.
A USB3 device needs to be reset and re-enumarated if the port it
connects to goes to a error state, with link state inactive.

There is no use in trying to recover failed transactions by resetting
endpoints at this stage. Tests show that in rare cases, after multiple
endpoint resets of a roothub port the whole host controller might stop
completely.

Several retries to recover from transaction error can happen as
it can take a long time before the hub thread discovers the USB3
port error and inactive link.

We can't reliably detect the port error from slot or endpoint context
due to a limitation in xhci, see xhci specs section 4.8.3:
"There are several cases where the EP State field in the Output
Endpoint Context may not reflect the current state of an endpoint"
and
"Software should maintain an accurate value for EP State, by tracking it
with an internal variable that is driven by Events and Doorbell accesses"

Same appears to be true for slot state.

set a flag to the corresponding slot if a USB3 roothub port link goes
inactive to prevent both queueing new URBs and resetting endpoints.

Reported-by: Rapolu Chiranjeevi <chiranjeevi.rapolu@intel.com>
Tested-by: Rapolu Chiranjeevi <chiranjeevi.rapolu@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-18 18:14:38 +02:00
Jim Lin
ef513be0a9 usb: xhci: Add Clear_TT_Buffer
USB 2.0 specification chapter 11.17.5 says "as part of endpoint halt
processing for full-/low-speed endpoints connected via a TT, the host
software must use the Clear_TT_Buffer request to the TT to ensure
that the buffer is not in the busy state".

In our case, a full-speed speaker (ConferenceCam) is behind a high-
speed hub (ConferenceCam Connect), sometimes once we get STALL on a
request we may continue to get STALL with the folllowing requests,
like Set_Interface.

Here we invoke usb_hub_clear_tt_buffer() to send Clear_TT_Buffer
request to the hub of the device for the following Set_Interface
requests to the device to get ACK successfully.

Signed-off-by: Jim Lin <jilin@nvidia.com>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 11:54:38 +02:00
Fabio Estevam
c1a145a3ed xhci: Use %zu for printing size_t type
Commit 597c56e372 ("xhci: update bounce buffer with correct sg num")
caused the following build warnings:

drivers/usb/host/xhci-ring.c:676:19: warning: format '%ld' expects argument of type 'long int', but argument 3 has type 'size_t {aka unsigned int}' [-Wformat=]

Use %zu for printing size_t type in order to fix the warnings.

Fixes: 597c56e372 ("xhci: update bounce buffer with correct sg num")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22 18:17:16 +02:00
Mathias Nyman
13b82b7463 xhci: Fix immediate data transfer if buffer is already DMA mapped
xhci immediate data transfer (IDT) support in 5.2-rc1 caused regression
on various Samsung Exynos boards with ASIX USB 2.0 ethernet dongle.

If the transfer buffer in the URB is already DMA mapped then IDT should
not be used. urb->transfer_dma will already contain a valid dma address,
and there is no guarantee the data in urb->transfer_buffer is valid.

The IDT support patch used urb->transfer_dma as a temporary storage,
copying data from urb->transfer_buffer into it.

Issue was solved by preventing IDT if transfer buffer is already dma
mapped, and by not using urb->transfer_dma as temporary storage.

Fixes: 33e39350eb ("usb: xhci: add Immediate Data Transfer support")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
CC: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22 14:25:37 +02:00
Henry Lin
597c56e372 xhci: update bounce buffer with correct sg num
This change fixes a data corruption issue occurred on USB hard disk for
the case that bounce buffer is used during transferring data.

While updating data between sg list and bounce buffer, current
implementation passes mapped sg number (urb->num_mapped_sgs) to
sg_pcopy_from_buffer() and sg_pcopy_to_buffer(). This causes data
not get copied if target buffer is located in the elements after
mapped sg elements. This change passes sg number for full list to
fix issue.

Besides, for copying data from bounce buffer, calling dma_unmap_single()
on the bounce buffer before copying data to sg list can avoid cache issue.

Fixes: f9c589e142 ("xhci: TD-fragment, align the unsplittable case with a bounce buffer")
Cc: <stable@vger.kernel.org> # v4.8+
Signed-off-by: Henry Lin <henryl@nvidia.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-22 14:25:36 +02:00
Mathias Nyman
d70d5a8466 xhci: add port and bus number to port dynamic debugging
Improve port related dynamic debugging by printing out the bus number,
port number and port status register content each time there is a port
related debug messages.

Use the same port numbering method as usbcore to simplify debugging.
i.e. starting with port number 1.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27 14:53:58 +02:00
Nicolas Saenz Julienne
33e39350eb usb: xhci: add Immediate Data Transfer support
Immediate data transfers (IDT) allow the HCD to copy small chunks of
data (up to 8bytes) directly into its output transfer TRBs. This avoids
the somewhat expensive DMA mappings that are performed by default on
most URBs submissions.

In the case an URB was suitable for IDT. The data is directly copied
into the "Data Buffer Pointer" region of the TRB and the IDT flag is
set. Instead of triggering memory accesses the HC will use the data
directly.

The implementation could cover all kind of output endpoints. Yet
Isochronous endpoints are bypassed as I was unable to find one that
matched IDT's constraints. As we try to bypass the default DMA mappings
on URB buffers we'd need to find a Isochronous device with an
urb->transfer_buffer_length <= 8 bytes.

The implementation takes into account that the 8 byte buffers provided
by the URB will never cross a 64KB boundary.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Reviewed-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>
2019-04-27 14:53:58 +02:00
Mathias Nyman
6cbcf59693 xhci: Fix port resume done detection for SS ports with LPM enabled
A suspended SS port in U3 link state will go to U0 when resumed, but
can almost immediately after that enter U1 or U2 link power save
states before host controller driver reads the port status.

Host controller driver only checks for U0 state, and might miss
the finished resume, leaving flags unclear and skip notifying usb
code of the wake.

Add U1 and U2 to the possible link states when checking for finished
port resume.

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-22 17:16:05 +01:00
Mathias Nyman
f6187f424c xhci: move bus_state structure under the xhci_hub structure.
Move the bus_state structure under struct usb_hub.

We need a bus_state strucure for each roothub to keep track of suspend
related info for each port.
Instead of keeping an array of two bus_state structures right under
struct xhci, it makes more sense move them to the xhci_hub structure.

No functional changes.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-07 15:40:41 +01:00
Cherian, George
11644a7659 xhci: Add quirk to workaround the errata seen on Cavium Thunder-X2 Soc
Implement workaround for ThunderX2 Errata-129 (documented in
CN99XX Known Issues" available at Cavium support site).
As per ThunderX2errata-129, USB 2 device may come up as USB 1
if a connection to a USB 1 device is followed by another connection to
a USB 2 device, the link will come up as USB 1 for the USB 2 device.

Resolution: Reset the PHY after the USB 1 device is disconnected.
The PHY reset sequence is done using private registers in XHCI register
space. After the PHY is reset we check for the PLL lock status and retry
the operation if it fails. From our tests, retrying 4 times is sufficient.

Add a new quirk flag XHCI_RESET_PLL_ON_DISCONNECT to invoke the workaround
in handle_xhci_port_status().

Cc: stable@vger.kernel.org
Signed-off-by: George Cherian <george.cherian@cavium.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-09 08:31:09 -08:00
Aaron Ma
958c0bd860 usb: xhci: fix uninitialized completion when USB3 port got wrong status
Realtek USB3.0 Card Reader [0bda:0328] reports wrong port status on
Cannon lake PCH USB3.1 xHCI [8086:a36d] after resume from S3,
after clear port reset it works fine.

Since this device is registered on USB3 roothub at boot,
when port status reports not superspeed, xhci_get_port_status will call
an uninitialized completion in bus_state[0].
Kernel will hang because of NULL pointer.

Restrict the USB2 resume status check in USB2 roothub to fix hang issue.

Cc: stable@vger.kernel.org
Signed-off-by: Aaron Ma <aaron.ma@canonical.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-09 08:31:09 -08:00
Sandeep Singh
d9193efba8 xhci: Add check for invalid byte size error when UAS devices are connected.
Observed "TRB completion code (27)" error which corresponds to Stopped -
Length Invalid error(xhci spec section 4.17.4) while connecting USB to
SATA bridge.

Looks like this case was not considered when the following patch[1] was
committed. Hence adding this new check which can prevent
the invalid byte size error.

[1] ade2e3a xhci: handle transfer events without TRB pointer

Cc: <stable@vger.kernel.org>
Signed-off-by: Sandeep Singh <sandeep.singh@amd.com>
cc: Nehal Shah <Nehal-bakulchandra.Shah@amd.com>
cc: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-09 08:31:08 -08:00
Mathias Nyman
1245374e9b xhci: handle port status events for removed USB3 hcd
At xhci removal the USB3 hcd (shared_hcd) is removed before the primary
USB2 hcd. Interrupts for port status changes may still occur for USB3
ports after the shared_hcd is freed, causing  NULL pointer dereference.

Check if xhci->shared_hcd is still valid before handing USB3 port events

Cc: <stable@vger.kernel.org>
Reported-by: Peter Chen <peter.chen@nxp.com>
Tested-by: Jack Pham <jackp@codeaurora.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-09 08:31:08 -08:00
Anshuman Gupta
330e2d61cd xhci: Avoid USB autosuspend when resuming USB2 ports.
When USB bus host controller root hub resumes from autosuspend,
it immediately tries to enter auto-suspend, but there can be a
scenario when root hub is resuming its usb2 ports, in that particular
case USB host controller auto suspend fails since it is busy
to resuming its usb2 ports.

This makes multiple failed cycles of auto-suspend until all usb2
ports of host controller root hub do not resume.

This patch uses USB core framework usb_hcd_start_port_resume,
usb_hcd_end_port_resume API's in order to  autoresume/autosuspend
root hub properly.

Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-28 15:04:45 +02:00
Mathias Nyman
f8f80be501 xhci: Use soft retry to recover faster from transaction errors
Use soft retry to recover from a USB Transaction Errors that are caused by
temporary error conditions. The USB device is not aware that the xHC
has halted the endpoint, and will be waiting for another retry

A Soft Retry perform additional retries and recover from an error which has
caused the xHC to halt an endpoint.

Soft retry has some limitations:
Soft Retry attempts shall not be performed on Isoch endpoints
Soft Retry attempts shall not be performed if the device is behind a TT in
a HS Hub

Software shall limit the number of unsuccessful Soft Retry attempts to
prevent an infinite loop.

For more details on Soft retry see xhci specs  4.6.8.1

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-28 15:04:45 +02:00
Mathias Nyman
eaefcf246b xhci: change xhci_test_and_clear_bit() to use new port structure
Don't use pointers to port array and port index as function parameters
in xhci_test_and_clear_bit(), just use a pointer to the right port
structure.

xhci_test_and_clear_bit() was the last port_array user in
xhci_get_port_status() and handle_port_status(), so remove the
port_array from them as well.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-24 18:03:08 +02:00
Mathias Nyman
6b7f40f712 xhci: change xhci_set_link_state() to work with port structures
Remove old iomem port array and index as parameters, just
send a ponter to a port strucure instread

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-24 18:03:08 +02:00
Mathias Nyman
74e6ad583a xhci: rename faked_port_index to hcd_portnum
hcd_portnum is a better desctiption than faked_port_index, and
is in line with the name the port structure uses.

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-24 18:03:08 +02:00
Mathias Nyman
52c7755ba1 xhci: xhci-ring: use port structures for port event handler
use port structures in the port event handler.
Getting the right hcd and hcd portnumber from the hardware port number
is a lot easier with port structures, and allows us to remove a lot
of the previous code, including the find_faked_portnum_from_hw_index()
function

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-24 18:03:08 +02:00
Mathias Nyman
f5249461b5 xhci: Clear the host side toggle manually when endpoint is soft reset
Some devices use a clear endpoint halt request as a soft reset, even if
the endpoint is not halted. This will clear the toggle and sequence on the
device side.

xHCI however refuses to reset a non-halted endpoint, so instead
we need to issue a configure endpoint command on xHCI to clear its host
side toggle and sequence, and get it in sync with the device side.

This is a respin of a old patch that was reverted as it had a stale
endpoint context dequeue value which caused regression.
commit 27082e2654 ("xhci: Clear the host side toggle manually when
endpoint is 'soft reset'")

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-16 15:40:19 +01:00
Mathias Nyman
a38fe33889 xhci: Don't always run the default stop endpoint command completion handler
The default stop endpoint completion handler will give back cancelled
URBs, and clean, or move past those canceller TRBs on the ring.

This is not always the preferred action.

If the stop endpoint command issuer is waiting for a completion
skip the default handler and just call the completion.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-16 15:40:18 +01:00
Lu Baolu
0c341910cb usb: xhci: Remove ep_trb from finish_td()
Function argument ep_trb for finish_td() isn't needed anymore.
Cleanup it.

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>
2018-03-16 15:40:18 +01:00
Lu Baolu
5fee5a5afa usb: xhci: Remove ep_trb from xhci_cleanup_halted_endpoint()
Function argument ep_trb for xhci_cleanup_halted_endpoint() isn't
needed anymore. Cleanup it.

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>
2018-03-16 15:40:18 +01:00
Greg Kroah-Hartman
d9e3d899bc Merge 4.15-rc4 into usb-next
We want the USB fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-18 09:08:05 +01:00
Chunfeng Yun
72b663a99c usb: xhci: fix TDS for MTK xHCI1.1
For MTK's xHCI 1.0 or latter, TD size is the number of max
packet sized packets remaining in the TD, not including
this TRB (following spec).

For MTK's xHCI 0.96 and older, TD size is the number of max
packet sized packets remaining in the TD, including this TRB
(not following spec).

Cc: stable <stable@vger.kernel.org>
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-08 18:26:34 +01:00
Lu Baolu
67d2ea9fde usb: xhci: Make some static functions global
This patch makes some static functions global to avoid duplications
in different files. These functions can be used in the implementation
of xHCI debug capability. There is no functional change.

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>
2017-12-08 17:43:52 +01:00
Mathias Nyman
103afda0e6 xhci: remove unnecessary boolean parameter from xhci_alloc_command
commands with input contexts are allocated with the
xhci_alloc_command_with_ctx helper.

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-08 17:43:52 +01:00
Corentin Labbe
58e8a4dad3 usb: xhci: remove unused variable ep_ring
Fix the build warning about variable 'ep_ring' set but not used

[Minor commit message change -Mathias]
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-08 17:43:52 +01:00
Corentin Labbe
ce5b2a6857 usb: xhci: remove unused variable urb_priv
Fix the build warning: variable 'urb_priv' set but not used

Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-08 17:43:52 +01:00
Mathias Nyman
e4ec40ec4b xhci: Don't show incorrect WARN message about events for empty rings
xHC can generate two events for a short transfer if the short TRB and
last TRB in the TD are not the same TRB.

The driver will handle the TD after the first short event, and remove
it from its internal list. Driver then incorrectly prints a warning
for the second event:

"WARN Event TRB for slot x ep y with no TDs queued"

Fix this by not printing a warning if we get a event on a empty list
if the previous event was a short event.

Cc: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-01 15:24:58 +00:00
Greg Kroah-Hartman
9ed64195e3 USB: host: xhci: Remove redundant license text
Now that the SPDX tag is in all USB files, that identifies the license
in a specific and legally-defined manner.  So the extra GPL text wording
can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text.  And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-07 15:45:02 +01:00
Greg Kroah-Hartman
5fd54ace47 USB: add SPDX identifiers to all remaining files in drivers/usb/
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/usb/ and include/linux/usb* files with the correct
SPDX license identifier based on the license text in the file itself.
The SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04 11:48:02 +01:00
Greg Kroah-Hartman
0520d37bb3 Merge 4.14-rc6 into usb-next
We need the USB fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-23 14:24:37 +02:00
Kees Cook
66a4550308 xhci: Convert timers to use timer_setup()
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: Mathias Nyman <mathias.nyman@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-17 12:14:43 +02:00
Lu Baolu
810a624bd1 usb: xhci: Reset halted endpoint if trb is noop
When a URB is cancled, xhci driver turns the untransferred trbs
into no-ops.  If an endpoint stalls on a no-op trb that belongs
to the cancelled URB, the event handler won't reset the endpoint.
Hence, it will stay halted.

Link: http://marc.info/?l=linux-usb&m=149582598330127&w=2

Cc: <stable@vger.kernel.org>
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>
2017-10-17 10:38:13 +02:00
Jeffy Chen
d1aad52cf8 xhci: Cleanup current_cmd in xhci_cleanup_command_queue()
KASAN reported use-after-free bug when xhci host controller died:
[  176.952537] BUG: KASAN: use-after-free in xhci_handle_command_timeout+0x68/0x224
[  176.960846] Write of size 4 at addr ffffffc0cbb01608 by task kworker/3:3/1680
...
[  177.180644] Freed by task 0:
[  177.183882]  kasan_slab_free+0x90/0x15c
[  177.188194]  kfree+0x114/0x28c
[  177.191630]  xhci_cleanup_command_queue+0xc8/0xf8
[  177.196916]  xhci_hc_died+0x84/0x358

Problem here is that when the cmd_timer fired, it would try to access
current_cmd while the command queue is already freed by xhci_hc_died().

Cleanup current_cmd in xhci_cleanup_command_queue() to avoid that.

Fixes: d9f11ba9f1 ("xhci: Rework how we handle unresponsive or hoptlug removed hosts")
Cc: <stable@vger.kernel.org> # v4.12+
Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-17 10:38:12 +02:00
Adam Wallis
49d5b05e19 xhci: allow TRACE to work with EVENT ring dequeue
inc_deq() currently bails earlier for EVENT rings than the common return
point of the function, due to the fact that EVENT rings do not have
link TRBs. The unfortunate side effect of this is that the very useful
trace_xhci_inc_deq() function is not called/usable for EVENT ring
debug.

This patch provides a refactor by removing the multiple return exit
points into a single return which additionally allows for all rings to
use the trace function.

Signed-off-by: Adam Wallis <awallis@codeaurora.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-05 11:01:58 +02:00
Anshuman Gupta
0914ea66d2 usb: xhci: reduce device initiated resume time variance.
This patch will improve the variable auto-resume latency of an usb-port.

The attempt to sync the start of root hub polling with resume time
signaling finish was ruined by a later request to start immediate
root hub polling.

When xhci gets a port status change event interrupt due to PORT_PLC
(port link state transition), linux Host controller driver drives the
resume signalling on the bus for the amount of time defined by
USB_REUME_TIMEOUT(40ms) macro.

This 40ms delay for resume signalling is in acceptable limit, but
it get worse when xhci goes for polling mode in order to detect other
events on its ports and modify rh_timer timer with a variable time out of
1ms to (HZ/4)ms.

drivers/usb/core/hcd.c line 799
mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4)).

Due to above variable timeout usb auto-resume latency varies from
40ms to ~300ms.

Log Snippet:
~128ms latency
[   53.112049] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0000
[   53.229200] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0004
[   53.240177] usb 1-2: usb wakeup-resume
[   53.240195] usb 1-2: finish resume
[   53.240357] usb usb1-port2: resume, status 0
-----------------------------------------------------------------
~300ms latency
[   59.946620] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0000
[   59.979341] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0000
[   60.229342] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0004
[   60.251321] usb 1-2: usb wakeup-resume
[   60.251335] usb 1-2: finish resume
[   60.251539] usb usb1-port2: resume, status 0

This variable resume latency can be optimized, as in case of PORT_PLC
change event rh_timer has already been modified with USB_RESUME_TIMEOUT
(40ms) delay,leaving the rest to GetPortStatus and started polling for
root hub status (invoking usb_hcd_poll_rh_status).
We can avoid polling as we have already modified rh_timer with
delay of 40ms.

This patch set the HCD_FLAG_POLL_RH to hcd->flags after modification of
rh_timer, and avoids polling of root hub status. so rh_timer can fire
after 40ms and usb device auto-resuem latency will be around 40ms.

[topic and first two senctences of commit message changed -Mathias]
Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-05 11:01:58 +02:00
Mathias Nyman
8ca1358bd9 xhci: add port status tracing
Track the port status in a human readble way each time we get a
port status change event

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-16 15:26:26 -07:00
Mathias Nyman
76a0f32b28 xhci: rename temp and temp1 variables
temp and temp1 variables are used for port status (portsc) and
command register. Give them more descriptive names

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-16 15:26:26 -07:00
Mathias Nyman
4b895868bb xhci: Fix NULL pointer dereference when cleaning up streams for removed host
This off by one in stream_id indexing caused NULL pointer dereference and
soft lockup on machines with USB attached SCSI devices connected to a
hotpluggable xhci controller.

The code that cleans up pending URBs for dead hosts tried to dereference
a stream ring at the invalid stream_id 0.
ep->stream_info->stream_rings[0] doesn't point to a ring.

Start looping stream_id from 1 like in all the other places in the driver,
and check that the ring exists before trying to kill URBs on it.

Reported-by: rocko r <rockorequin@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-20 14:40:35 +02:00
Mathias Nyman
3134bc9c52 xhci: cleanup finish_td() skip option
finish_td() could be called with a skip option to bypass most of the
function and only call xhci_td_cleanup() at the end.

Remove this skip option and call xhci_td_cleanup() directly instead
when needed

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-15 22:17:46 +02:00
Mathias Nyman
d36374fdfb xhci: cleanup virtual endoint structure, remove stopped_stream
Get rid of stopped_stream member in virtual endpoint structure as
it is only used in one case when cleaning a halted endpoint.

Pass it as function parameter instead.

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-15 22:17:46 +02:00
Mathias Nyman
ade2e3a148 xhci: handle transfer events without TRB pointer
Most transfer events have a TRB pointer indicating which TRB caused
the event.
In the case of streams, transfer events such as
USB Transaction error may have its TRB pointer set to zero.

driver won't know which stream or what TRB on that stream caused
the error, but it can issue a soft reset to recover the transfer.
A soft reset will clear the host side halt of the endpoint without
clearing Data toggle or sequence number, and let the transfer
continue from where it halted.

see xhci section 4.12 streams and 4.6.8.2 soft retry.

USB Transaction errors with a zero TRB pointer are seen with
UAS usb devices.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-15 22:17:46 +02:00
Mathias Nyman
5eee4b6b4f xhci: support calling cleanup_halted_endpoint with soft retry
Add soft reset support to cleanup_halted_endpoint().
using soft reset will prevent it from setting a new dequeue pointer to
start the transfer from. Let it continue where it halted.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-15 22:17:46 +02:00
Mathias Nyman
217491487c xhci: Add support for endpoint soft reset
xhci supports soft retry recovery when the host halted the host side of an
endopint but the connected USB device is not aware of the halt.

In this case xhci needs to issue a reset endopint command  with a TSP
(Transfer State Preserve) flag set which preserves the Data toggle
and Sequence number of the endpoint.

This feature is needed to handle a few special transfer event types
such as USB Transaction error that don't always point to a causing TRB.

see xhci 4.6.8.1 for more details

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-15 22:17:46 +02:00
Mathias Nyman
b3368382ef xhci: refactor transfer event errors and completion codes
Parse the transfer event first, and remove duplicate debugging
code.

Reorder completion codes according to endpoint state.

No functional changes

We are not handling some transfer events correcly and need to
clean up this before fixing it

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-15 22:17:46 +02:00
Mathias Nyman
e6b20121c6 xhci: Add helper to get hardware dequeue pointer for stopped rings.
Add xhci_get_hw_deq() helper to retrieve the hardware dequeue pointer an
endpoint or stream stopped on.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 18:02:58 +09:00
Mathias Nyman
8790736dbf xhci: Add stream id to xhci_dequeue_state structure
The values for the new dequeue segment, new dequeue pointer and new cycle
state are needed for manually moving the xHC ring dequeue pointer.
These are conveniently stored in a xhci_dequeue_state structure.

stream support was added later and stream_id was carried
as a function parameter.

Move the stream_id to the xhci_dequeue_state structure instead.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 18:02:58 +09:00
Mathias Nyman
cdd504e113 xhci: Find out where an endpoint or stream stopped from its context.
When xHC is asked to stop an endpoint it will save the position it
stopped on in the endpoint or stream context.

xhci driver needs to know if the controller stopped on the exact same
TRB that the driver was asked to cancel as it then needs to move past
the TD instead of turning the TD to no-op TRBs.

xhci driver used to get the stopped position from a "stopped" transfer
event before the stop endpoint command completed, but if the ring
is already stopped, or in a halted or error state this event is missing.

Get the stopped position from the endpoint or stream context instead

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 18:02:58 +09:00
Mathias Nyman
11e1d25db6 xhci: remove unused stopped_td pointer
We no longer keep track of where we stopped in a stopped_td pointer.
We get the ring dequeue pointer from the endpoint or stream context

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-03 18:02:58 +09:00
Mathias Nyman
604d02a2a6 xhci: Fix command ring stop regression in 4.11
In 4.11 TRB completion codes were renamed to match spec.

Completion codes for command ring stopped and endpoint stopped
were mixed, leading to failures while handling a stopped command ring.

Use the correct completion code for command ring stopped events.

Fixes: 0b7c105a04 ("usb: host: xhci: rename completion codes to match spec")
Cc: <stable@vger.kernel.org> # 4.11
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18 15:19:42 +02:00
Alan Stern
63aea0dbab USB: xhci: fix lock-inversion problem
With threaded interrupts, bottom-half handlers are called with
interrupts enabled.  Therefore they can't safely use spin_lock(); they
have to use spin_lock_irqsave().  Lockdep warns about a violation
occurring in xhci_irq():

=========================================================
[ INFO: possible irq lock inversion dependency detected ]
4.11.0-rc8-dbg+ #1 Not tainted
---------------------------------------------------------
swapper/7/0 just changed the state of lock:
 (&(&ehci->lock)->rlock){-.-...}, at: [<ffffffffa0130a69>]
ehci_hrtimer_func+0x29/0xc0 [ehci_hcd]
but this lock took another, HARDIRQ-unsafe lock in the past:
 (hcd_urb_list_lock){+.....}

and interrupts could create inverse lock ordering between them.

other info that might help us debug this:
 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(hcd_urb_list_lock);
                               local_irq_disable();
                               lock(&(&ehci->lock)->rlock);
                               lock(hcd_urb_list_lock);
  <Interrupt>
    lock(&(&ehci->lock)->rlock);
 *** DEADLOCK ***

no locks held by swapper/7/0.
the shortest dependencies between 2nd lock and 1st lock:
 -> (hcd_urb_list_lock){+.....} ops: 252 {
    HARDIRQ-ON-W at:
                      __lock_acquire+0x602/0x1280
                      lock_acquire+0xd5/0x1c0
                      _raw_spin_lock+0x2f/0x40
                      usb_hcd_unlink_urb_from_ep+0x1b/0x60 [usbcore]
                      xhci_giveback_urb_in_irq.isra.45+0x70/0x1b0 [xhci_hcd]
                      finish_td.constprop.60+0x1d8/0x2e0 [xhci_hcd]
                      xhci_irq+0xdd6/0x1fa0 [xhci_hcd]
                      usb_hcd_irq+0x26/0x40 [usbcore]
                      irq_forced_thread_fn+0x2f/0x70
                      irq_thread+0x149/0x1d0
                      kthread+0x113/0x150
                      ret_from_fork+0x2e/0x40

This patch fixes the problem.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: Bart Van Assche <bart.vanassche@sandisk.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18 15:19:42 +02:00
Peter Chen
6a29beef9d usb: host: xhci-ring: don't need to clear interrupt pending for MSI enabled hcd
According to xHCI spec Figure 30: Interrupt Throttle Flow Diagram

	If PCI Message Signaled Interrupts (MSI or MSI-X) are enabled,
       	then the assertion of the Interrupt Pending (IP) flag in Figure 30
       	generates a PCI Dword write. The IP flag is automatically cleared
       	by the completion of the PCI write.

the MSI enabled HCs don't need to clear interrupt pending bit, but
hcd->irq = 0 doesn't equal to MSI enabled HCD. At some Dual-role
controller software designs, it sets hcd->irq as 0 to avoid HCD
requesting interrupt, and they want to decide when to call usb_hcd_irq
by software.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18 15:19:41 +02:00
Mathias Nyman
7bc5d5aff3 usb: xhci: trace URB before giving it back instead of after
Don't access any members of a URB after giving it back.
URB might be freed by then already.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18 15:19:41 +02:00
Lu Baolu
8c10152ec5 usb: xhci: remove xhci_debug_trb()
Every XHCI TRB has already been traced by the trb trace events.
It is unnecessary to put the same message in kernel log. This
patch removes xhci_debug_trb().

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>
2017-04-08 12:17:42 +02:00
Lu Baolu
121dcf1190 usb: xhci: remove ring debugging code
XHCI ring changes have already been traced by the ring trace
events. It's unnecessary to put the same messages in kernel
log. This patch removes the debugging code for a ring.

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>
2017-04-08 12:17:41 +02:00
Lu Baolu
cd12fd9f6d usb: xhci: remove enq_updates and deq_updates from ring
enq_updates and deq_updates were introduced in the first place
to check whether an xhci hardware is able to respond to trbs
enqueued in the ring. We now have trb tracers to trace every
single enqueue/dequeue trb. It's time to remove them and the
associated debugging code.

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>
2017-04-08 12:17:41 +02:00
Lu Baolu
74e0b5649c usb: xhci: remove error messages for failed memory allocation
Omit extra messages for memory allocation failure.

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>
2017-04-08 12:17:41 +02:00
Lu Baolu
b2d6edbb95 usb: xhci: add xhci_log_ring trace events
This patch creates a new event class called xhci_log_ring, and
defines the events used for tracing the change of all kinds of
rings used by an xhci host. An xHCI ring is basically a memory
block shared between software and hardware. By tracing changes
of rings, it makes the life easier for debugging hardware or
software problems.

This info can be used, later, to print, in a human readable way,
the life cycle of an xHCI ring using the trace-cmd tool and the
appropriate plugin.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-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>
2017-04-08 12:17:41 +02:00
Mathias Nyman
d9f11ba9f1 xhci: Rework how we handle unresponsive or hoptlug removed hosts
Introduce a new xhci_hc_died() function that takes care of handling
pending commands and URBs if a host controller becomes unresponsive.

This addresses issues on hotpluggable xhci controllers that disappear
from the bus suddenly, often while the bus (PCI) remove function is
still being processed.

xhci_hc_died() sets a XHCI_STATUS_DYING flag to prevent new URBs and
commands or to be queued. The flag also ensures xhci_hc_died() will
give back pending commands and URBs once.

Host is considered dead if register read returns 0xffffffff, or host
fails to abort the command ring, or fails stopping an endpoint after
trying for 5 seconds.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 12:17:41 +02:00
Zhengjun Xing
b7f769ae1b xhci: add slot and endpoint numbers to debug messages in handle_tx_event
There's one annoyance in how xhci prints debug messages, we often
get logs with messages but it's hard to say from which device and
endpoint the message originates. Add slot_id, ep_index messages
in handle_tx_event.

Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 12:17:41 +02:00
Felipe Balbi
19a7d0d65c usb: host: xhci: add Slot and EP Context tracers
With these, we can track what's happening with the HW while executing
each and every command. It will give us visibility into how the
different contexts are being modified by xHC which can bring insight
into problems while debugging.

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>
2017-04-08 12:17:41 +02:00
Mathias Nyman
0ab2881a40 xhci: Set URB actual length for stopped control transfers
A control transfer that stopped at the status stage incorrectly
warned about a "unexpected TRB Type 4", and did not set the
transferred actual_length for the URB.

The URB actual_length for control transfers should contain the
bytes transferred in the data stage.

Bytes of a partially sent setup stage and missing bytes from
status stage should be left out.

Cc: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-29 12:13:49 +02:00
Mathias Nyman
7e64b0373a xhci: simplify how we store TDs in urb private data
Instead of storing a zero length array of td pointers, and then
allocate memory both for the td pointer array and the td's, just
use a zero length array of actual td's in urb private data.

old:

struct urb_priv {
       struct xhci_td *td[0]
}

new:

struct urb_priv {
        struct xhci_td td[0]
}

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 11:00:02 +01:00
Mathias Nyman
9ef7fbbb4f xhci: Rename variables related to transfer descritpors
urb_priv structure has a count on how many TDs the
URB contains, and how many of those TD's we have handled.

rename:
length -> num_tds
td_cnt -> num_tds_done

No functional changes

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-25 11:00:02 +01:00
Felipe Balbi
5abdc2e6e1 usb: host: xhci: add urb_enqueue/dequeue/giveback tracers
These three new tracers will help us tie TRBs into URBs by *also*
looking into URB lifetime.

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>
2017-01-25 11:00:01 +01:00
Felipe Balbi
a37c3f76e6 usb: host: xhci: make a generic TRB tracer
instead of having a tracer that can only trace command completions,
let's promote this tracer so it can trace and decode any TRB.

With that, it will be easier to extrapolate the lifetime of any TRB
which might help debugging certain issues.

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>
2017-01-25 11:00:01 +01:00
Felipe Balbi
a54cfae3c7 usb: host: xhci: convert to list_for_each_entry_safe()
instead of using while(!list_empty()) followed by list_first_entry(), we
can actually use list_for_each_entry_safe().

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>
2017-01-25 10:59:07 +01:00
Mathias Nyman
5278204c98 xhci: use the trb_to_noop() helper for command trbs
Remove duplicate code by using trb_to_noop() when
handling Aborted commads

Based on earlier code 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>
2017-01-25 10:59:07 +01:00
Mathias Nyman
ae1e3f0732 xhci: Introduce helper to turn one TRB into a no-op
Useful for turning both transfer and command trbs
into no-ops.

Based on earlier code 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>
2017-01-25 10:59:07 +01:00
Felipe Balbi
a60f2f2ffa usb: host: xhci: unconditionally call xhci_unmap_td_bounce_buffer()
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>
2017-01-25 10:59:06 +01:00
Felipe Balbi
f45e2a0211 usb: host: xhci: check for a valid ring when unmapping bounce buffer
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>
2017-01-25 10:59:06 +01:00
Felipe Balbi
f3899a28e2 usb: host: xhci: remove bogus __releases()/__acquires() annotation
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>
2017-01-25 10:59:06 +01:00
Felipe Balbi
55fa4396b2 usb: host: xhci: introduce xhci_td_cleanup()
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>
2017-01-25 10:59:06 +01:00
Felipe Balbi
be0f50c2e3 usb: host: xhci: reorder variable definitions
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>
2017-01-25 10:59:06 +01:00
Felipe Balbi
04861f8336 usb: host: xhci: use slightly better list helpers
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>
2017-01-25 10:59:06 +01:00
Felipe Balbi
76a35293b9 usb: host: xhci: simplify irq handler return
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>
2017-01-25 10:59:06 +01:00
Felipe Balbi
0b7c105a04 usb: host: xhci: rename completion codes to match spec
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>
2017-01-25 10:59:06 +01:00
Lu Baolu
daa47f2132 usb: xhci: use list_is_singular for cmd_list
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>
2017-01-25 10:57:35 +01:00
Lu Baolu
fb79a6da45 usb: xhci: avoid unnecessary calculation
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>
2017-01-25 10:57:35 +01:00
Lu Baolu
80c479622f usb: xhci: remove unnecessary assignment
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>
2017-01-25 10:57:35 +01:00
Lu Baolu
1cc6d8617b usb: xhci: remove unnecessary second abort try
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>
2017-01-25 10:57:35 +01:00
Mathias Nyman
6b02e97491 xhci: remove unnecessary check for pending timer
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>
2017-01-25 10:57:35 +01:00
Mathias Nyman
f99265965b xhci: detect stop endpoint race using pending timer instead of counter.
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>
2017-01-25 10:57:34 +01:00