1. 27 3月, 2013 1 次提交
  2. 26 3月, 2013 6 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
    • 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/acpi: binding xhci root hub usb port with ACPI · bafcaf6d
      Lan Tianyu 提交于
      This patch is to bind xhci root hub usb port with its acpi node.
      The port num in the acpi table matches with the sequence in the xhci
      extended capabilities table. So call usb_hcd_find_raw_port_number() to
      transfer hub port num into raw port number which associates with
      the sequence in the xhci extended capabilities table before binding.
      Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
      Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
      bafcaf6d
    • 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
  3. 24 3月, 2013 2 次提交
  4. 23 3月, 2013 6 次提交
  5. 22 3月, 2013 24 次提交
  6. 21 3月, 2013 1 次提交