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  1. 04 1月, 2013 6 次提交
    • S
      USB: Ignore port state until reset completes. · 4f43447e
      由 Sarah Sharp 提交于 
      The port reset code bails out early if the current connect status is
cleared (device disconnected).  If we're issuing a hot reset, it may
also look at the link state before the reset is finished.

Section 10.14.2.6 of the USB 3.0 spec says that when a port enters the
Error state or Resetting state, the port connection bit retains the
value from the previous state.  Therefore we can't trust it until the
reset finishes.  Also, the xHCI spec section 4.19.1.2.5 says software
shall ignore the link state while the port is resetting, as it can be in
an unknown state.

The port state during reset is also unknown for USB 2.0 hubs.  The hub
sends a reset signal by driving the bus into an SE0 state.  This
overwhelms the "connect" signal from the device, so the port can't tell
whether anything is connected or not.

Fix the port reset code to ignore the port link state and current
connect bit until the reset finishes, and USB_PORT_STAT_RESET is
cleared.

Remove the check for USB_PORT_STAT_C_BH_RESET in the warm reset case,
because it's redundant.  When the warm reset finishes, the port reset
bit will be cleared at the same time USB_PORT_STAT_C_BH_RESET is set.
Remove the now-redundant check for a cleared USB_PORT_STAT_RESET bit
in the code to deal with the finished reset.

This patch should be backported to all stable kernels.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: stable@vger.kernel.org
      4f43447e
    • S
      USB: Increase reset timeout. · 77c7f072
      由 Sarah Sharp 提交于 
      John's NEC 0.96 xHCI host controller needs a longer timeout for a warm
reset to complete.  The logs show it takes 650ms to complete the warm
reset, so extend the hub reset timeout to 800ms to be on the safe side.

This commit should be backported to kernels as old as 3.2, that contain
the commit 75d7cf72 "usbcore: refine
warm reset logic".
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Reported-by: NJohn Covici <covici@ccs.covici.com>
Cc: stable@vger.kernel.org
      77c7f072
    • S
      USB: Allow USB 3.0 ports to be disabled. · 41e7e056
      由 Sarah Sharp 提交于 
      If hot and warm reset fails, or a port remains in the Compliance Mode,
the USB core needs to be able to disable a USB 3.0 port.  Unlike USB 2.0
ports, once the port is placed into the Disabled link state, it will not
report any new device connects.  To get device connect notifications, we
need to put the link into the Disabled state, and then the RxDetect
state.

The xHCI driver needs to atomically clear all change bits on USB 3.0
port disable, so that we get Port Status Change Events for future port
changes.  We could technically do this in the USB core instead of in the
xHCI roothub code, since the port state machine can't advance out of the
disabled state until we set the link state to RxDetect.  However,
external USB 3.0 hubs don't need this code.  They are level-triggered,
not edge-triggered like xHCI, so they will continue to send interrupt
events when any change bit is set.  Therefore it doesn't make sense to
put this code in the USB core.

This patch is part of a series to fix several reports of infinite loops
on device enumeration failure.  This includes John, when he boots with
a USB 3.0 device (Roseweil eusb3 enclosure) attached to his NEC 0.96
host controller.  The fix requires warm reset support, so it does not
make sense to backport this patch to stable kernels without warm reset
support.

This patch should be backported to kernels as old as 3.2, contain the
commit ID 75d7cf72 "usbcore: refine warm
reset logic"
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Reported-by: NJohn Covici <covici@ccs.covici.com>
Cc: stable@vger.kernel.org
      41e7e056
    • S
      USB: Ignore xHCI Reset Device status. · 8b8132bc
      由 Sarah Sharp 提交于 
      When the USB core finishes reseting a USB device, the xHCI driver sends
a Reset Device command to the host.  The xHC then updates its internal
representation of the USB device to the 'Default' device state.  If the
device was already in the Default state, the xHC will complete the
command with an error status.

If a device needs to be reset several times during enumeration, the
second reset will always fail because of the xHCI Reset Device command.
This can cause issues during enumeration.

For example, usb_reset_and_verify_device calls into hub_port_init in a
loop.  Say that on the first call into hub_port_init, the device is
successfully reset, but doesn't respond to several set address control
transfers.  Then the port will be disabled, but the udev will remain in
tact.  usb_reset_and_verify_device will call into hub_port_init again.

On the second call into hub_port_init, the device will be reset, and the
xHCI driver will issue a Reset Device command.  This command will fail
(because the device is already in the Default state), and
usb_reset_and_verify_device will fail.  The port will be disabled, and
the device won't be able to enumerate.

Fix this by ignoring the return value of the HCD reset_device callback.

This commit should be backported to kernels as old as 3.2, that contain
the commit 75d7cf72 "usbcore: refine
warm reset logic".
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: stable@vger.kernel.org
      8b8132bc
    • S
      USB: Handle auto-transition from hot to warm reset. · 1c7439c6
      由 Sarah Sharp 提交于 
      USB 3.0 hubs and roothubs will automatically transition a failed hot
reset to a warm (BH) reset.  In that case, the warm reset change bit
will be set, and the link state change bit may also be set.  Change
hub_port_finish_reset to unconditionally clear those change bits for USB
3.0 hubs.  If these bits are not cleared, we may lose port change events
from the roothub.

This commit should be backported to kernels as old as 3.2, that contain
the commit 75d7cf72 "usbcore: refine
warm reset logic".
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: stable@vger.kernel.org
      1c7439c6
    • S
      xhci: Handle HS bulk/ctrl endpoints that don't NAK. · 55c1945e
      由 Sarah Sharp 提交于 
      A high speed control or bulk endpoint may have bInterval set to zero,
which means it does not NAK.  If bInterval is non-zero, it means the
endpoint NAKs at a rate of 2^(bInterval - 1).

The xHCI code to compute the NAK interval does not handle the special
case of zero properly.  The current code unconditionally subtracts one
from bInterval and uses it as an exponent.  This causes a very large
bInterval to be used, and warning messages like these will be printed:

usb 1-1: ep 0x1 - rounding interval to 32768 microframes, ep desc says 0 microframes

This may cause the xHCI host hardware to reject the Configure Endpoint
command, which means the HS device will be unusable under xHCI ports.

This patch should be backported to kernels as old as 2.6.31, that contain
commit dfa49c4a "USB: xhci - fix math in
xhci_get_endpoint_interval()".
Reported-by: NVincent Pelletier <plr.vincent@gmail.com>
Suggested-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
      55c1945e
  3. 22 12月, 2012 34 次提交