This patch (as1675) removes the CONFIG_USB_SUSPEND option, essentially
replacing it everywhere with CONFIG_PM_RUNTIME (except for one place
in hub.c, where it is replaced with CONFIG_PM because the code needs
to be used in both runtime and system PM).  The net result is code
shrinkage and simplification.

There's very little point in keeping CONFIG_USB_SUSPEND because almost
everybody enables it.  The few that don't will find that the usbcore
module has gotten somewhat bigger and they will have to take active
measures if they want to prevent hubs from being runtime suspended.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
CC: Peter Chen <peter.chen@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1674) speeds up system sleep transitions by not
suspending each individual device on a USB-1.1 or USB-2 bus.  The
devices will automatically go into suspend when their root hubs are
suspended (i.e., stop sending out Start-Of-Frame packets) -- this is
what the USB spec calls "global suspend".

Since this is what we do already when CONFIG_USB_SUSPEND isn't
enabled, it shouldn't cause any problems.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
CC: Peter Chen <peter.chen@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1673) reduces the amount of log spew from the hub driver
by removing a bunch of error messages in the case where the device in
question is already known to have been disconnected.  Since the
disconnect event itself appears in the log, there's no need for other
error messages.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Tested-by: NJenya Y <jy.gerstmaier@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Return an error if hub->descriptor->bNbrPorts==0. Without this additional
check, we can end up doing a "hub->ports = kzalloc(0, GFP_KERNEL)".
This hub->ports pointer will therefore be non-NULL and will be used.
Example of dmesg:
   INIT: usb 1-1: New USB device found, idVendor=0424, idProduct=2512
   usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
   hub 1-1:1.0: USB hub found
   version 2.86 bootinghub 1-1:1.0: 0 ports detected
   Unable to handle kernel NULL pointer dereference at virtual address 00000010
Signed-off-by: NDavid Linares <dlinares.linux@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If one storage interface or usb network interface(iSCSI case) exists in
current configuration, memory allocation with GFP_KERNEL during
usb_device_reset() might trigger I/O transfer on the storage interface
itself and cause deadlock because the 'us->dev_mutex' is held in
.pre_reset() and the storage interface can't do I/O transfer when the
reset is triggered by other interface, or the error handling can't be
completed if the reset is triggered by the storage itself (error
handling path).
Signed-off-by: NMing Lei <ming.lei@canonical.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Decotigny <david.decotigny@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oneukum@suse.de>
Reviewed-by: NJiri Kosina <jkosina@suse.cz>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch is to add usb port auto power off mechanism.
When usb device is suspending, usb core will suspend usb port and
usb port runtime pm callback will clear PORT_POWER feature to
power off port if all conditions were met. These conditions are
remote wakeup disable, pm qos NO_POWER_OFF flag clear and persist
enable. When it resumes, power on port again.

Add did_runtime_put in the struct usb_port to ensure
pm_runtime_get/put(portdev) to be called pairedly.  Set did_runtime_put
to true when call pm_runtime_put(portdev) during suspending. The
pm_runtime_get(portdev) only will be called when did_runtime_put
is set to true during resuming. Set did_runtime_put to false after
calling pm_runtime_get(portdev).

Make clear_port_feature() and hdev_to_hub() as global symbol.
Rename clear_port_feature() to usb_clear_port_feature() and
hdev_to_hub() to usb_hub_to_struct_hub().

Extend hub_port_debounce() with the fuction of debouncing to
be connected. Add two wraps: hub_port_debounce_be_connected()
and hub_port_debouce_be_stable().

Increase HUB_DEBOUNCE_TIMEOUT to 2000 because some usb ssds
needs around 1.5 or more to make the hub port status to be
connected steadily after being powered off and powered on.
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch is to add runtime pm callback for usb port device.
Set/clear PORT_POWER feature in the resume/suspend callback.
Add portnum for struct usb_port to record port number. Do
pm_rumtime_get_sync/put(portdev) when a device is plugged/unplugged
to prevent it from being powered off when it is active.
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Usb3.0 device defines function remote wakeup which is only for interface
recipient rather than device recipient. This is different with usb2.0 device's
remote wakeup feature which is defined for device recipient. According usb3.0
spec 9.4.5, the function remote wakeup can be modified by the SetFeature()
requests using the FUNCTION_SUSPEND feature selector. This patch is to use
correct way to disable usb3.0 device's function remote wakeup after suspend
error and resuming.

This should be backported to kernels as old as 3.4, that contain the
commit 623bef9e "USB/xhci: Enable remote
wakeup for USB3 devices."
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org

ACPI provide "_PLD" and "_UPC" aml methods to describe usb port
visibility and connectability. This patch is to add usb_hub_adjust_DeviceRemovable()
to adjust usb hub port's DeviceRemovable according ACPI information and invoke it in
the rh_call_control(). When hub descriptor request is issued at first time,
usb port device isn't created and usb port is not bound with acpi. So first
hub descriptor request is not changed based on ACPI information. After usb
port devices being created, call usb_hub_adjust_DeviceRemovable in the hub_configure()
and then set hub port's DeviceRemovable according ACPI information and this also works
for non-root hub.
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

To show the relationship between usb port and child device,
add link file "port" under usb device's sysfs directoy and
"device" under usb port device's sysfs directory. They are linked
to each other.
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch is to create driver/usb/core/(port.c,hub.h) files and move usb
port related code into port.c.
Signed-off-by: NLan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Sarah pointed out that the USB3.0 spec also updates the amount of power
that may be consumed by the device and quoted 9.2.5.1:

|"The amount of current draw for SuperSpeed devices are increased to 150
|mA for low-power devices and 900 mA for high-power"

This patch tries to update all users to use the larger values for
SuperSpeed devices and use the "old" ones for everything else.

While here, two other changes suggested by Alan:
- the comment referering to 7.2.1.1 has been updated to 7.2.1 which is
  the correct source of the action.
- the check for hubs with zero ports has been removed.
- compute bus power by full_load * num_ports on root hubs
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The USB 2.0 specification says that bMaxPower is the maximum power
consumption expressed in 2 mA units and the USB 3.0 specification says
that it is expressed in 8 mA units.
This patch adds a helper function usb_get_max_power() which computes the
value based on config & usb_device's speed value. The the device descriptor
dump computes the value on its own.

Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Some touchscreens have buggy firmware which claims
remote wakeup to be enabled after a reset. They nevertheless
crash if the feature is cleared by the host.
Add a check for reset resume before checking for
an enabled remote wakeup feature. On compliant
devices the feature must be cleared after a reset anyway.
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Refactor hub_port_wait_reset into a small loop to wait for the port
reset to be complete, and then a larger block to deal with the final
port status.  This patch should not change any current behavior.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>

Change the code that manually issues a Set Port Feature(Link State) to
use the new helper function hub_set_port_link_state().
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>

A USB 3.0 device can transition to the Inactive state if a U1 or U2 exit
transition fails.  The current code in hub_events simply issues a warm
reset, but does not call any pre-reset or post-reset driver methods (or
unbind/rebind drivers without them).  Therefore the drivers won't know
their device has just been reset.

hub_events should instead call usb_reset_device.  This means
hub_port_reset now needs to figure out whether it should issue a warm
reset or a hot reset.

Remove the FIXME note about needing disconnect() for a NOTATTACHED
device.  This patch fixes that.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>

When a hot reset fails on a USB 3.0 port, the current port reset code
recursively calls hub_port_reset inside hub_port_wait_reset.  This isn't
ideal, since we should avoid recursive calls in the kernel, and it also
doesn't allow us to issue multiple warm resets on reset failures.

Rip out the recursive call.  Instead, add code to hub_port_reset to
issue a warm reset if the hot reset fails, and try multiple warm resets
before giving up on the port.

In hub_port_wait_reset, remove the recursive call and re-indent.  The
code is basically the same, except:

1. It bails out early if the port has transitioned to Inactive or
Compliance Mode after the reset completed.

2. It doesn't consider a connect status change to be a failed reset.  If
multiple warm resets needed to be issued, the connect status may have
changed, so we need to ignore that and look at the port link state
instead.  hub_port_reset will now do that.

3. It unconditionally sets udev->speed on all types of successful
resets.  The old recursive code would set the port speed when the second
hub_port_reset returned.

The old code did not handle connected devices needing a warm reset well.
There were only two situations that the old code handled correctly: an
empty port needing a warm reset, and a hot reset that migrated to a warm
reset.

When an empty port needed a warm reset, hub_port_reset was called with
the warm variable set.  The code in hub_port_finish_reset would skip
telling the USB core and the xHC host that the device was reset, because
otherwise that would result in a NULL pointer dereference.

When a USB 3.0 device reset migrated to a warm reset, the recursive call
made the call stack look like this:

hub_port_reset(warm = false)
        hub_wait_port_reset(warm = false)
                hub_port_reset(warm = true)
                        hub_wait_port_reset(warm = true)
                        hub_port_finish_reset(warm = true)
                        (return up the call stack to the first wait)

        hub_port_finish_reset(warm = false)

The old code didn't want to notify the USB core or the xHC host of device reset
twice, so it only did it in the second call to hub_port_finish_reset,
when warm was set to false.  This was necessary because
before patch two ("USB: Ignore xHCI Reset Device status."), the USB core
would pay attention to the xHC Reset Device command error status, and
the second call would always fail.

Now that we no longer have the recursive call, and warm can change from
false to true in hub_port_reset, we need to have hub_port_finish_reset
unconditionally notify the USB core and the xHC of the device reset.

In hub_port_finish_reset, unconditionally clear the connect status
change (CSC) bit for USB 3.0 hubs when the port reset is done.  If we
had to issue multiple warm resets for a device, that bit may have been
set if the device went into SS.Inactive and then was successfully warm
reset.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>

The next patch will refactor the hub port code to rip out the recursive
call to hub_port_reset on a failed hot reset.  In preparation for that,
make sure all code paths can deal with being called with a NULL udev.
The usb_device will not be valid if warm reset was issued because a port
transitioned to the Inactive or Compliance Mode on a device connect.

This patch should have no effect on current behavior.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>

The EHCI host controller needs to prevent EHCI initialization when the
UHCI or OHCI companion controller is in the middle of a port reset.  It
uses ehci_cf_port_reset_rwsem to do this.  USB 3.0 hubs can't be under
an EHCI host controller, so it makes no sense to down the semaphore for
USB 3.0 hubs.  It also makes the warm port reset code more complex.

Don't down ehci_cf_port_reset_rwsem for USB 3.0 hubs.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>

An empty port can transition to either Inactive or Compliance Mode if a
newly connected USB 3.0 device fails to link train.  In that case, we
issue a warm reset.  Some devices, such as John's Roseweil eusb3
enclosure, slip back into Compliance Mode after the warm reset.

The current warm reset code does not check for device connect status on
warm reset completion, and it incorrectly reports the warm reset
succeeded.  This causes the USB core to attempt to send a Set Address
control transfer to a port in Compliance Mode, which will always fail.

Make hub_port_wait_reset check the current connect status and link state
after the warm reset completes.  Return a failure status if the device
is disconnected or the link state is Compliance Mode or SS.Inactive.

Make hub_events disable the port if warm reset fails.  This will disable
the port, and then bring it back into the RxDetect state.  Make the USB
core ignore the connect change until the device reconnects.

Note that this patch does NOT handle connected devices slipping into the
Inactive state very well.  This is a concern, because devices can go
into the Inactive state on U1/U2 exit failure.  However, the fix for
that case is too large for stable, so it will be submitted in a separate
patch.

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

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

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

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

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

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

The old parameter "port" is useless for phy notify, as one usb
phy is only for one usb port. New parameter "speed" stands for
the device's speed which is on the port, this "speed" parameter
is needed at some platforms which will do some phy operations
according to device's speed.
Signed-off-by: NPeter Chen <peter.chen@freescale.com>
Tested-by: NMike Thompson <mpthompson@gmail.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

At commit 925aa46b, Richard Zhao
<richard.zhao@freescale.com> adds the phy notification callback
when port change occurs. In fact, this phy notification should
be added according to below rules:

1. Only set HW_USBPHY_CTRL.ENHOSTDISCONDETECT
during high speed host mode.
2. Do not set HW_USBPHY_CTRL.ENHOSTDISCONDETECT
during the reset and speed negotiation period.
3. Do not set HW_USBPHY_CTRL.ENHOSTDISCONDETECT
during host suspend/resume sequence.

Please refer: i.mx23RM(page: 413) for below rules.
http://www.freescale.com/files/dsp/doc/ref_manual/IMX23RM.pdf

Freescale i.MX SoC, i.mx23, i.mx28 and i.mx6(i.mx6SL does not
need to follow the 3rd rule) need to follow above rules.

Current code set connect notification (HW_USBPHY_CTRL.ENHOSTDISCONDETECT)
at hub_port_connect_change, it conflicts with above the 2th rule.

The correct notification setting method should be:
1. Set connect notify after the second bus reset.
2. Set disconnect notify after disconnection.
Signed-off-by: NPeter Chen <peter.chen@freescale.com>
Tested-by: NMike Thompson <mpthompson@gmail.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1621) removes the limit on the number of loops allowed
in hub_tt_work().  The value is arbitrary, and it's silly to have a
limit in the first place -- anything beyond the limit would not get
handled.

Besides, it's most unlikely that we'll ever need to clear more than a
couple of TT buffers at any time.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

dev_<level> calls take less code than dev_printk(KERN_<LEVEL>
and reducing object size is good.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch sets hub device's default autosuspend delay as 0 to
speedup bus suspend, see comments in code for details.
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NMing Lei <ming.lei@canonical.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The hub status endpoint has a long 'bInterval', which is 255ms
for FS/LS device and 256ms for HS device according to USB 2.0 spec,
so the device connection change may be reported later more than 255ms
via status pipe.

The connection change in hub may have been happened already on the
downstream ports, but no status URB completes when it is killed
in hub_suspend(auto), so the connection change may be missed by some
buggy hub devices, which won't generate remote wakeup signal after
their remote wakeup is enabled and they are put into suspend state.

The problem can be observed at least on the below Genesys Logic, Inc.
hub devices:

	0x05e3,0x0606
	0x05e3,0x0608

In theory, there is no way to fix the problem completely, but we
can make it less likely to occur by this patch.

This patch introduces one quirk of HUB_QUIRK_CHECK_PORTS_AUTOSUSPEND
to check ports' change during hub_suspend(auto) for the buggy
devices. If ports' change is found, terminate the auto suspend and
return to working state.

So for the buggy hubs, if the connection change happend before
the ports' check, it can be handled correctly. If it happens between
the ports' check and enabling remote wakeup/entering suspend, it
will be missed. Considered the interval is quite short, it is very
less likely to happen during the window.
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NMing Lei <ming.lei@canonical.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch (as1620) speeds up USB root-hub resumes in the common case
where every enabled port has its suspend feature set (which currently
will be true for every runtime resume of the root hub).  If all the
enabled ports are suspended then resuming the root hub won't resume
any of the downstream devices.  In this case there's no need for a
Resume Recovery delay, because that delay is meant to give devices a
chance to get ready for active use.

To keep track of the port suspend features, the patch adds a
"port_is_suspended" flag to struct usb_device.  This has to be tracked
separately from the device's state; it's entirely possible for a USB-2
device to be suspended while the suspend feature on its parent port is
clear.  The reason is that devices will go into suspend whenever their
parent hub does.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Reviewed-by: NPeter Chen <peter.chen@freescale.com>
Tested-by: NPeter Chen <peter.chen@freescale.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

flush_work_sync and flush_work are now the same and flush_work_sync
has been deprecated. This fixes the following warning:

drivers/usb/core/hub.c: In function hub_quiesce:
drivers/usb/core/hub.c:1216:3: warning: flush_work_sync is deprecated (declared at include/linux/workqueue.h:448) [-Wdeprecated-declarations]
Reported-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There is a race condition in the USB hub code with regard to handling
TT clear requests that can get the HCD driver in a deadlock. Usually
when an TT clear request is scheduled it will be executed immediately:

<7>[    6.077583] usb 2-1.3: unlink qh1-0e01/f4d4db00 start 0 [1/2 us]
<3>[    6.078041] usb 2-1: clear tt buffer port 3, a3 ep2 t04048d82
<7>[    6.078299] hub_tt_work:731
<7>[    9.309089] usb 2-1.5: link qh1-0e01/f4d506c0 start 0 [1/2 us]
<7>[    9.324526] ehci_hcd 0000:00:1d.0: reused qh f4d4db00 schedule
<7>[    9.324539] usb 2-1.3: link qh1-0e01/f4d4db00 start 0 [1/2 us]
<7>[    9.341530] usb 1-1.1: link qh4-0e01/f397aec0 start 2 [1/2 us]
<7>[   10.116159] usb 2-1.3: unlink qh1-0e01/f4d4db00 start 0 [1/2 us]
<3>[   10.116459] usb 2-1: clear tt buffer port 3, a3 ep2 t04048d82
<7>[   10.116537] hub_tt_work:731

However, if a suspend operation is triggered before hub_tt_work is
scheduled, hub_quiesce will cancel the work without notifying the HCD
driver:

<3>[   35.033941] usb 2-1: clear tt buffer port 3, a3 ep2 t04048d80
<5>[   35.034022] sd 0:0:0:0: [sda] Stopping disk
<7>[   35.034039] hub 2-1:1.0: hub_suspend
<7>[   35.034067] usb 2-1: unlink qh256-0001/f3b1ab00 start 1 [1/0 us]
<7>[   35.035085] hub 1-0:1.0: hub_suspend
<7>[   35.035102] usb usb1: bus suspend, wakeup 0
<7>[   35.035106] ehci_hcd 0000:00:1a.0: suspend root hub
<7>[   35.035298] hub 2-0:1.0: hub_suspend
<7>[   35.035313] usb usb2: bus suspend, wakeup 0
<7>[   35.035315] ehci_hcd 0000:00:1d.0: suspend root hub
<6>[   35.250017] PM: suspend of devices complete after 216.979 msecs
<6>[   35.250822] PM: late suspend of devices complete after 0.799 msecs
<7>[   35.252343] ehci_hcd 0000:00:1d.0: wakeup: 1
<7>[   35.262923] ehci_hcd 0000:00:1d.0: --> PCI D3hot
<7>[   35.263302] ehci_hcd 0000:00:1a.0: wakeup: 1
<7>[   35.273912] ehci_hcd 0000:00:1a.0: --> PCI D3hot
<6>[   35.274254] PM: noirq suspend of devices complete after 23.442 msecs
<6>[   35.274975] ACPI: Preparing to enter system sleep state S3
<6>[   35.292666] PM: Saving platform NVS memory
<7>[   35.295030] Disabling non-boot CPUs ...
<6>[   35.297351] CPU 1 is now offline
<6>[   35.300345] CPU 2 is now offline
<6>[   35.303929] CPU 3 is now offline
<7>[   35.303931] lockdep: fixing up alternatives.
<6>[   35.304825] Extended CMOS year: 2000

When the device will resume the EHCI driver will get stuck in
ehci_endpoint_disable waiting for the tt_clearing flag to reset:

<0>[   47.610967] usb 2-1.3: **** DPM device timeout ****
<7>[   47.610972]  f2f11c60 00000092 f2f11c0c c10624a5 00000003 f4c6e880 c1c8a4c0 c1c8a4c0
<7>[   47.610983]  15c55698 0000000b f56b34c0 f2a45b70 f4c6e880 00000082 f2a4602c f2f11c30
<7>[   47.610993]  c10787f8 f4cac000 f2a45b70 00000000 f4cac010 f2f11c58 00000046 00000001
<7>[   47.611004] Call Trace:
<7>[   47.611006]  [<c10624a5>] ? sched_clock_cpu+0xf5/0x160
<7>[   47.611019]  [<c10787f8>] ? lock_release_holdtime.part.22+0x88/0xf0
<7>[   47.611026]  [<c103ed46>] ? lock_timer_base.isra.35+0x26/0x50
<7>[   47.611034]  [<c17592d3>] ? schedule_timeout+0x133/0x290
<7>[   47.611044]  [<c175b43e>] schedule+0x1e/0x50
<7>[   47.611051]  [<c17592d8>] schedule_timeout+0x138/0x290
<7>[   47.611057]  [<c10624a5>] ? sched_clock_cpu+0xf5/0x160
<7>[   47.611063]  [<c103e560>] ? usleep_range+0x40/0x40
<7>[   47.611070]  [<c1759445>] schedule_timeout_uninterruptible+0x15/0x20
<7>[   47.611077]  [<c14935f4>] ehci_endpoint_disable+0x64/0x160
<7>[   47.611084]  [<c147d1ee>] ? usb_hcd_flush_endpoint+0x10e/0x1d0
<7>[   47.611092]  [<c1165663>] ? sysfs_add_file+0x13/0x20
<7>[   47.611100]  [<c147d5a9>] usb_hcd_disable_endpoint+0x29/0x40
<7>[   47.611107]  [<c147fafc>] usb_disable_endpoint+0x5c/0x80
<7>[   47.611111]  [<c147fb57>] usb_disable_interface+0x37/0x50
<7>[   47.611116]  [<c1477650>] usb_reset_and_verify_device+0x4b0/0x640
<7>[   47.611122]  [<c1474665>] ? hub_port_status+0xb5/0x100
<7>[   47.611129]  [<c147a975>] usb_port_resume+0xd5/0x220
<7>[   47.611136]  [<c148877f>] generic_resume+0xf/0x30
<7>[   47.611142]  [<c14821a3>] usb_resume+0x133/0x180
<7>[   47.611147]  [<c1473b10>] ? usb_dev_thaw+0x10/0x10
<7>[   47.611152]  [<c1473b1d>] usb_dev_resume+0xd/0x10
<7>[   47.611157]  [<c13baa60>] dpm_run_callback+0x40/0xb0
<7>[   47.611164]  [<c13bdb03>] ? pm_runtime_enable+0x43/0x70
<7>[   47.611171]  [<c13bafc6>] device_resume+0x1a6/0x2c0
<7>[   47.611177]  [<c13ba940>] ? dpm_show_time+0xe0/0xe0
<7>[   47.611183]  [<c13bb0f9>] async_resume+0x19/0x40
<7>[   47.611189]  [<c10580c4>] async_run_entry_fn+0x64/0x160
<7>[   47.611196]  [<c104a244>] ? process_one_work+0x104/0x480
<7>[   47.611203]  [<c104a24c>] ? process_one_work+0x10c/0x480
<7>[   47.611209]  [<c104a2c0>] process_one_work+0x180/0x480
<7>[   47.611215]  [<c104a244>] ? process_one_work+0x104/0x480
<7>[   47.611220]  [<c1058060>] ? async_schedule+0x10/0x10
<7>[   47.611226]  [<c104c15c>] worker_thread+0x11c/0x2f0
<7>[   47.611233]  [<c104c040>] ? manage_workers.isra.27+0x1f0/0x1f0
<7>[   47.611239]  [<c10507f8>] kthread+0x78/0x80
<7>[   47.611244]  [<c1750000>] ? timer_cpu_notify+0xd6/0x20d
<7>[   47.611253]  [<c1050780>] ? __init_kthread_worker+0x60/0x60
<7>[   47.611258]  [<c176357e>] kernel_thread_helper+0x6/0xd
<7>[   47.611283] ------------[ cut here ]------------

This patch changes hub_quiesce behavior to flush the TT clear work
instead of canceling it, to make sure that no TT clear request remains
uncompleted before suspend.
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

SEL and PEL are in microseconds, not milliseconds.  Also, fix a split
string that will trigger checkpatch warnings.
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>

The Set SEL control transfer tells a device the exit latencies
associated with a device-initated U1 or U2 exit.  Since a parent hub may
initiate a transition to U1 soon after a downstream port's U1 timeout is
set, we need to make sure the device receives the Set SEL transfer
before the parent hub timeout is set.

This patch should be backported to kernels as old as 3.5, that contain
the commit 1ea7e0e8 "USB: Add support to
enable/disable USB3 link states."
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org

Some USB 3.0 devices signal that they don't implement Link PM by having
all zeroes in the U1/U2 exit latencies in their SuperSpeed BOS
descriptor.  Don found that a Western Digital device he has experiences
transfer errors when LPM is enabled.  The lsusb shows the U1/U2 exit
latencies are set to zero:

Binary Object Store Descriptor:
  bLength                 5
  bDescriptorType        15
  wTotalLength           22
  bNumDeviceCaps          2
  SuperSpeed USB Device Capability:
    bLength                10
    bDescriptorType        16
    bDevCapabilityType      3
    bmAttributes         0x00
      Latency Tolerance Messages (LTM) Supported
    wSpeedsSupported   0x000e
      Device can operate at Full Speed (12Mbps)
      Device can operate at High Speed (480Mbps)
      Device can operate at SuperSpeed (5Gbps)
    bFunctionalitySupport   1
      Lowest fully-functional device speed is Full Speed (12Mbps)
    bU1DevExitLat           0 micro seconds
    bU2DevExitLat           0 micro seconds

The fix is to not enable LPM for a particular link state if we find its
corresponding exit latency is zero.

This patch should be backported to kernels as old as 3.5, that contain
the commit 1ea7e0e8 "USB: Add support to
enable/disable USB3 link states."
Signed-off-by: NSarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: NDon Zickus <dzickus@redhat.com>
Tested-by: NDon Zickus <dzickus@redhat.com>
Cc: stable@vger.kernel.org

This reverts commit ca9c9d0c.

Rafael wants more time to work on the user api to handle port power
issues, so let's just revert the sysfs changes for now.
Reported-by: NRafael J. Wysocki <rjw@sisk.pl>
Cc: Lan Tianyu <tianyu.lan@intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Commit ff823c79 ("usb: move children
to struct usb_port") forgot to consider the hub_disconnect sequence,
which releases ports before quiescing the hub, which will lead to a
use-after-free, since hub_quiesce() will try to disconnect ports'
children, which are already deallocated. Simple modprobe dummy_hcd &&
rmmod dummy_hcd will illustrate the problem.

This patch moves deallocation of hub's ports after hub_quiesce() call
in hub_disconnect().

Cc: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: NAlexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>