1. 02 4月, 2013 1 次提交
  2. 29 3月, 2013 7 次提交
  3. 26 3月, 2013 12 次提交
    • S
      USB: EHCI: fix bug in iTD/siTD DMA pool allocation · 85ecd032
      Soeren Moch 提交于
      [Description written by Alan Stern]
      
      Soeren tracked down a very difficult bug in ehci-hcd's DMA pool
      management of iTD and siTD structures.  Some background: ehci-hcd
      gives each isochronous endpoint its own set of active and free itd's
      (or sitd's for full-speed devices).  When a new itd is needed, it is
      taken from the head of the free list, if possible.  However, itd's
      must not be used twice in a single frame because the hardware
      continues to access the data structure for the entire duration of a
      frame.  Therefore if the itd at the head of the free list has its
      "frame" member equal to the current value of ehci->now_frame, it
      cannot be reused and instead a new itd is allocated from the DMA pool.
      The entries on the free list are not released back to the pool until
      the endpoint is no longer in use.
      
      The bug arises from the fact that sometimes an itd can be moved back
      onto the free list before itd->frame has been set properly.  In
      Soeren's case, this happened because ehci-hcd can allocate one more
      itd than it actually needs for an URB; the extra itd may or may not be
      required depending on how the transfer aligns with a frame boundary.
      For example, an URB with 8 isochronous packets will cause two itd's to
      be allocated.  If the URB is scheduled to start in microframe 3 of
      frame N then it will require both itds: one for microframes 3 - 7 of
      frame N and one for microframes 0 - 2 of frame N+1.  But if the URB
      had been scheduled to start in microframe 0 then it would require only
      the first itd, which could cover microframes 0 - 7 of frame N.  The
      second itd would be returned to the end of the free list.
      
      The itd allocation routine initializes the entire structure to 0, so
      the extra itd ends up on the free list with itd->frame set to 0
      instead of a meaningful value.  After a while the itd reaches the head
      of the list, and occasionally this happens when ehci->now_frame is
      equal to 0.  Then, even though it would be okay to reuse this itd, the
      driver thinks it must get another itd from the DMA pool.
      
      For as long as the isochronous endpoint remains in use, this flaw in
      the mechanism causes more and more itd's to be taken slowly from the
      DMA pool.  Since none are released back, the pool eventually becomes
      exhausted.
      
      This reuslts in memory allocation failures, which typically show up
      during a long-running audio stream.  Video might suffer the same
      effect.
      
      The fix is very simple.  To prevent allocations from the pool when
      they aren't needed, make sure that itd's sent back to the free list
      prematurely have itd->frame set to an invalid value which can never be
      equal to ehci->now_frame.
      
      This should be applied to -stable kernels going back to 3.6.
      Signed-off-by: NSoeren Moch <smoch@web.de>
      Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
      Cc: stable <stable@vger.kernel.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      85ecd032
    • A
      USB: EHCI: remove unused variable in unlink_empty_async() · afc2c9a2
      Alan Stern 提交于
      This patch (as1669) removes the check_unlinks_later flag in ehci-hcd's
      unlink_empty_async().  It wasn't being used for anything and should
      have been removed in an earlier patch, but I forgot about it.
      Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      afc2c9a2
    • A
      USB: EHCI: improve end_unlink_async() · 214ac7a0
      Alan Stern 提交于
      This patch (as1665) changes the way ehci-hcd's end_unlink_async()
      routine works in order to avoid recursive execution and to be more
      efficient:
      
      	Now when an IAA cycle ends, a new one gets started up right
      	away (if it is needed) instead of waiting until the
      	just-unlinked QH has been processed.
      
      	The async_iaa list is renamed to async_idle, which better
      	expresses its new purpose: It is now the list of QHs which are
      	now completely idle and are waiting to be processed by
      	end_unlink_async().
      
      	A new flag is added to track whether an IAA cycle is in
      	progress, because the list formerly known as async_iaa no
      	longer stores the QHs waiting for the IAA to finish.
      
      	The decision about how many QHs to process when an IAA cycle
      	ends is now made at the end of the cycle, when we know the
      	current state of the hardware, rather than at the beginning.
      	This means a bunch of logic got moved from start_iaa_cycle()
      	to end_unlink_async().
      Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      214ac7a0
    • A
      USB: EHCI: convert singly-linked lists to list_heads · 6e018751
      Alan Stern 提交于
      This patch (as1664) converts ehci-hcd's async_unlink, async_iaa, and
      intr_unlink from singly-linked lists to standard doubly-linked
      list_heads.  Originally it didn't seem necessary to use list_heads,
      because items are always added to and removed from these lists in FIFO
      order.  But now with more list processing going on, it's easier to use
      the standard routines than continue with a roll-your-own approach.
      
      I don't know if the code ends up being notably shorter, but the
      patterns will be more familiar to any kernel hacker.
      Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      6e018751
    • A
      USB: EHCI: consolidate code in ehci_urb_dequeue() · 7655e316
      Alan Stern 提交于
      This patch (as1668) consolidates two nearly identical code paths in
      ehci_urb_dequeue().  The test for !qh can be removed because it will
      never succeed; the fact that usb_hcd_check_unlink_urb() returned 0
      means that urb must be queued and therefore urb->hcpriv must point to
      a QH.
      Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      7655e316
    • A
      USB: EHCI: split needs_rescan into two flags · 7bc782d7
      Alan Stern 提交于
      This patch (as1662) does some more QH-related cleanup in ehci-hcd.
      The qh->needs_rescan flag is currently used for two different
      purposes; the patch replaces it with two separate flags for greater
      clarity: qh->dequeue_during_giveback indicates that a completion
      handler dequeued an URB (implying that a rescan is needed), and
      qh->exception indicates that the QH is in an exceptional state
      requiring an unlink (either it encountered an I/O error or an unlink
      was requested).
      
      The new flags get set where the dequeue, exception, or unlink request
      occurred, rather than where the unlink is started.  This is so that in
      the future, if we need to, we will be able to tell apart unlinks that
      truly were required from those that were carried out merely because
      the QH wasn't being used.
      Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      7bc782d7
    • A
      USB: EHCI: change return value of qh_completions() · 79bcf7b0
      Alan Stern 提交于
      This patch (as1658) cleans up the usage of qh_completions() in
      ehci-hcd.  Currently the function's return value indicates whether any
      URBs were given back; the idea was that the caller can scan the QH
      over again to handle any URBs that were dequeued by a completion
      handler.  This is not necessary; when qh_completions() is ready to
      give back dequeued URBs, it does its own rescanning.
      
      Therefore the new return value will be a flag indicating whether the
      caller needs to unlink the QH.  This is more convenient than forcing
      the caller to check qh->needs_rescan, and it makes a lot more sense --
      why should "needs_rescan" imply that an unlink is needed?  The callers
      are also changed to remove the unneeded rescans.
      
      Lastly, the check for whether qh->qtd_list is non-empty is removed
      from the start of qh_completions().  Two of the callers have to make
      this test anyway, so the same test can simply be added to the other
      two callers.
      Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      79bcf7b0
    • A
      USB: EHCI: changes related to qh_refresh() · c1fdb68e
      Alan Stern 提交于
      This patch (as1638) makes several changes to the ehci-hcd driver, all
      related to the qh_refresh() function.  This function must be called
      whenever an idle QH gets linked back into either the async or the
      periodic schedule.
      
      	Change a BUG_ON() in the qh_update routine to a WARN_ON().
      	Since this code runs in atomic context, a BUG_ON() would
      	immediately freeze the whole system.
      
      	Remove two unneeded calls to qh_refresh(), one when a QH is
      	initialized and one when a QH becomes idle.  Adjust the
      	adjacent comments accordingly.
      
      	Move the qh_refresh() and qh_link_periodic() calls for new
      	interrupt URBs to after the new TDs have been added.
      
      	As a result of the previous two changes, qh_refresh() is never
      	called when the qtd_list is empty.  The corresponding check in
      	qh_refresh() can be removed, along with an indentation level.
      
      These changes should not cause any alteration of behavior.
      Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      c1fdb68e
    • S
      xhci: Don't warn on empty ring for suspended devices. · a83d6755
      Sarah Sharp 提交于
      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: NSarah Sharp <sarah.a.sharp@linux.intel.com>
      Tested-by: NStephen Hemminger <stephen@networkplumber.org>
      a83d6755
    • V
      usb: xhci: Fix TRB transfer length macro used for Event TRB. · 1c11a172
      Vivek Gautam 提交于
      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 b10de142 "USB: xhci:
      Bulk transfer support".  This patch will have issues applying to older
      kernels.
      Signed-off-by: NVivek gautam <gautam.vivek@samsung.com>
      Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
      Cc: stable@vger.kernel.org
      1c11a172
    • L
      usb: add find_raw_port_number callback to struct hc_driver() · 3f5eb141
      Lan Tianyu 提交于
      xhci driver divides the root hub into two logical hubs which work
      respectively for usb 2.0 and usb 3.0 devices. They are independent
      devices in the usb core. But in the ACPI table, it's one device node
      and all usb2.0 and usb3.0 ports are under it. Binding usb port with
      its acpi node needs the raw port number which is reflected in the xhci
      extended capabilities table. This patch is to add find_raw_port_number
      callback to struct hc_driver(), fill it with xhci_find_raw_port_number()
      which will return raw port number and add a wrap usb_hcd_find_raw_port_number().
      
      Otherwise, refactor xhci_find_real_port_number(). Using
      xhci_find_raw_port_number() to get real index in the HW port status
      registers instead of scanning through the xHCI roothub port array.
      This can help to speed up.
      
      All addresses in xhci->usb2_ports and xhci->usb3_ports array are
      kown good ports and don't include following bad ports in the extended
      capabilities talbe.
           (1) root port that doesn't have an entry
           (2) root port with unknown speed
           (3) root port that is listed twice and with different speeds.
      
      So xhci_find_raw_port_number() will only return port num of good ones
      and never touch bad ports above.
      Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
      Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
      3f5eb141
    • P
      usb: xhci: fix build warning · 09ce0c0c
      Peter Chen 提交于
      /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: NPeter Chen <peter.chen@freescale.com>
      Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
      09ce0c0c
  4. 22 3月, 2013 1 次提交
  5. 21 3月, 2013 1 次提交
    • A
      USB: EHCI: fix regression in QH unlinking · d714aaf6
      Alan Stern 提交于
      This patch (as1670) fixes a regression caused by commit
      6402c796 (USB: EHCI: work around
      silicon bug in Intel's EHCI controllers).  The workaround goes through
      two IAA cycles for each QH being unlinked.  During the first cycle,
      the QH is not added to the async_iaa list (because it isn't fully gone
      from the hardware yet), which means that list will be empty.
      
      Unfortunately, I forgot to update the IAA watchdog timer routine.  It
      thinks that an empty async_iaa list means the timer expiration was an
      error, which isn't true any more.  This problem didn't show up during
      initial testing because the controllers being tested all had working
      IAA interrupts.  But not all controllers do, and when the watchdog
      timer expires, the empty-list check prevents the second IAA cycle from
      starting.  As a result, URB unlinks never complete.  The check needs
      to be removed.
      
      Among the symptoms of the regression are processes stuck in D wait
      states and hangs during system shutdown.
      Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
      Reported-and-tested-by: NStephen Warren <swarren@wwwdotorg.org>
      Reported-and-tested-by: NSven Joachim <svenjoac@gmx.de>
      Reported-by: NAndreas Bombe <aeb@debian.org>
      Cc: stable <stable@vger.kernel.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      d714aaf6
  6. 19 3月, 2013 5 次提交
  7. 18 3月, 2013 1 次提交
    • D
      USB: xhci - fix bit definitions for IMAN register · f8264340
      Dmitry Torokhov 提交于
      According to XHCI specification (5.5.2.1) the IP is bit 0 and IE is bit 1
      of IMAN register. Previously their definitions were reversed.
      
      Even though there are no ill effects being observed from the swapped
      definitions (because IMAN_IP is RW1C and in legacy PCI case we come in
      with it already set to 1 so it was clearing itself even though we were
      setting IMAN_IE instead of IMAN_IP), we should still correct the values.
      
      This patch should be backported to kernels as old as 2.6.36, that
      contain the commit 4e833c0b "xhci: don't
      re-enable IE constantly".
      Signed-off-by: NDmitry Torokhov <dtor@vmware.com>
      Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
      Cc: stable@vger.kernel.org
      f8264340
  8. 16 3月, 2013 12 次提交