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82 Commits (c3492dbfa1050debf23a5b5cd2bc7514c5b37896)

Author SHA1 Message Date
Petr Mladek 37ebb54915 usb: hub: rename khubd to hub_wq in documentation and comments
USB hub has started to use a workqueue instead of kthread. Let's update
the documentation and comments here and there.

This patch mostly just replaces "khubd" with "hub_wq". There are only few
exceptions where the whole sentence was updated. These more complicated
changes can be found in the following files:

	   Documentation/usb/hotplug.txt
	   drivers/net/usb/usbnet.c
	   drivers/usb/core/hcd.c
	   drivers/usb/host/ohci-hcd.c
	   drivers/usb/host/xhci.c

Signed-off-by: Petr Mladek <pmladek@suse.cz>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-23 22:33:19 -07:00
Hans de Goede b7f9696bd1 xhci: xhci_ring_device: Ring stream ring bells for endpoints with streams
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-23 21:46:10 -07:00
Felipe Balbi 96908589a8 usb: host: xhci: fix compliance mode workaround
Commit 71c731a (usb: host: xhci: Fix Compliance Mode
on SN65LVP3502CP Hardware) implemented a workaround
for a known issue with Texas Instruments' USB 3.0
redriver IC but it left a condition where any xHCI
host would be taken out of reset if port was placed
in compliance mode and there was no device connected
to the port.

That condition would trigger a fake connection to a
non-existent device so that usbcore would trigger a
warm reset of the port, thus taking the link out of
reset.

This has the side-effect of preventing any xHCI host
connected to a Linux machine from starting and running
the USB 3.0 Electrical Compliance Suite because the
port will mysteriously taken out of compliance mode
and, thus, xHCI won't step through the necessary
compliance patterns for link validation.

This patch fixes the issue by just adding a missing
check for XHCI_COMP_MODE_QUIRK inside
xhci_hub_report_usb3_link_state() when PORT_CAS isn't
set.

This patch should be backported to all kernels containing
commit 71c731a.

Fixes: 71c731a (usb: host: xhci: Fix Compliance Mode on SN65LVP3502CP Hardware)
Cc: Alexis R. Cortes <alexis.cortes@ti.com>
Cc: <stable@vger.kernel.org> # v3.2+
Signed-off-by: Felipe Balbi <balbi@ti.com>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-09-08 14:30:42 -07:00
Lu Baolu ff8cbf250b xhci: clear root port wake on bits if controller isn't wake-up capable
When xHCI PCI host is suspended, if do_wakeup is false in xhci_pci_suspend,
xhci_bus_suspend needs to clear all root port wake on bits. Otherwise some Intel
platforms may get a spurious wakeup, even if PCI PME# is disabled.

This patch should be back-ported to kernels as old as 2.6.37, that
contains the commit 9777e3ce90
"USB: xHCI: bus power management implementation".

Cc: stable@vger.kernel.org # 2.6.37
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>
2014-06-24 12:29:35 -04:00
Mathias Nyman be3de32107 xhci: Fix sleeping with IRQs disabled in xhci_stop_device()
xhci_stop_device() allocates and issues stop commands for each active endpoint.
This is done with spinlock held and interrupt disabled so we can't sleep during
memory allocation. Use GFP_NOWAIT instead

Regression from commit ddba5cd0ae
"xhci: Use command structures when queuing commands on the command ring"
for 3.16-rc1

Fixes: ddba5cd0ae ("xhci: Use command structures when queuing commands")
Reported-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-17 16:44:57 -07:00
Mathias Nyman c311e391a7 xhci: rework command timeout and cancellation,
Use one timer to control command timeout.

start/kick the timer every time a command is completed and a
new command is waiting, or a new command is added to a empty list.

If the timer runs out, then tag the current command as "aborted", and
start the xhci command abortion process.

Previously each function that submitted a command had its own timer.
If that command timed out, a new command structure for the
command was created and it was put on a cancel_cmd_list list,
then a pci write to abort the command ring was issued.

when the ring was aborted, it checked if the current command
was the one to be canceled, later when the ring was stopped the
driver got ownership of the TRBs in the command ring,
compared then to the TRBs in the cancel_cmd_list,
and turned them into No-ops.

Now, instead, at timeout we tag the status of the command in the
command queue to be aborted, and start the ring abortion.
Ring abortion stops the command ring and gives control of the
commands to us.
All the aborted commands are now turned into No-ops.

If the ring is already stopped when the command times outs its not possible
to start the ring abortion, in this case the command is turnd to No-op
right away.

All these changes allows us to remove the entire cancel_cmd_list code.

The functions waiting for a command to finish no longer have their own timeouts.
They will wait either until the command completes normally,
or until the whole command abortion is done.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-20 10:03:25 +09:00
Mathias Nyman 9ea1833e4c xhci: Use completion and status in global command queue
Remove the per-device command list and handle_cmd_in_cmd_wait_list()
and use the completion and status variables found in the
command structure in the global command list.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-20 10:03:25 +09:00
Mathias Nyman ddba5cd0ae xhci: Use command structures when queuing commands on the command ring
To create a global command queue we require that each command put on the
command ring is submitted with a command structure.

Functions that queue commands and wait for completion need to allocate a command
before submitting it, and free it once completed. The following command queuing
functions need to be modified.

xhci_configure_endpoint()
xhci_address_device()
xhci_queue_slot_control()
xhci_queue_stop_endpoint()
xhci_queue_new_dequeue_state()
xhci_queue_reset_ep()
xhci_configure_endpoint()

xhci_configure_endpoint() could already be called with a command structure,
and only xhci_check_maxpacket and xhci_check_bandwidth did not do so. These
are changed and a command structure is now required. This change also simplifies
the configure endpoint command completion handling and the "goto bandwidth_change"
handling code can be removed.

In some cases the command queuing function is called in interrupt context.
These commands needs to be allocated atomically, and they can't wait for
completion. These commands will in this patch be freed directly after queuing,
but freeing will be moved to the command completion event handler in a later
patch once we get the global command queue up.(Just so that we won't leak
memory in the middle of the patch set)

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-20 10:03:25 +09:00
Sarah Sharp 25cd2882e2 usb/xhci: Change how we indicate a host supports Link PM.
The xHCI driver currently uses a USB core internal field,
udev->lpm_capable, to indicate the xHCI driver knows how to calculate
the LPM timeout values.  If this value is set for the host controller
udev, it means Link PM can be enabled for child devices under that host.

Change the code so the xHCI driver isn't mucking with USB core internal
fields.  Instead, indicate the xHCI driver doesn't support Link PM on
this host by clearing the U1 and U2 exit latencies in the roothub
SuperSpeed Extended Capabilities BOS descriptor.

The code to check for the roothub setting U1 and U2 exit latencies to
zero will also disable LPM for external devices that do that same.  This
was already effectively done with commit
ae8963adb4 "usb: Don't enable LPM if the
exit latency is zero."  Leave that code in place, so that if a device
sets one exit latency value to zero, but the other is set to a valid
value, LPM is only enabled for the U1 or U2 state that had the valid
value.  This is the same behavior the code had before.

Also, change messages about missing Link PM information from warning
level to info level.  Only print a warning about the first device that
doesn't support LPM, to avoid log spam.  Further, cleanup some
unnecessary line breaks to help people to grep for the error messages.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
2014-03-04 15:38:00 -08:00
Xenia Ragiadakou 204b7793f2 xhci: replace xhci_writel() with writel()
Function xhci_writel() is used to write a 32bit value in xHC registers residing
in MMIO address space. It takes as first argument a pointer to the xhci_hcd
although it does not use it. xhci_writel() internally simply calls writel().
This creates an illusion that xhci_writel() is an xhci specific function that
has to be called in a context where a pointer to xhci_hcd is available.

Remove xhci_writel() wrapper function and replace its calls with calls to
writel() to make the code more straight-forward.

Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2013-12-02 12:59:49 -08:00
Xenia Ragiadakou b0ba972084 xhci: replace xhci_readl() with readl()
Function xhci_readl() is used to read 32bit xHC registers residing in MMIO
address space. It takes as first argument a pointer to the xhci_hcd although
it does not use it. xhci_readl() internally simply calls readl(). This creates
an illusion that xhci_readl() is an xhci specific function that has to be
called in a context where a pointer to xhci_hcd is available.

Remove the unnecessary xhci_readl() wrapper function and replace its calls to
with calls to readl() to make the code more straightforward.

Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2013-12-02 12:59:48 -08:00
Greg Kroah-Hartman 9afcdb10ad xhci: Final patches for 3.13
Hi Greg,
 
 Here's my pull request for usb-next and 3.13.  My xHCI tree is closed
 after this point, since I won't be able to run my full tests while I'm in
 Scotland.  After Kernel Summit, I'll be on vacation with access to email
 from Oct 26th to Nov 6th.
 
 Here's what's in this request:
 
  - Patches to fix USB 2.0 Link PM issues that cause USB 3.0 devices to not
    enumerate or misbehave when plugged into a USB 2.0 port.  Those are
    marked for stable.
 
  - A msec vs jiffies bug fix by xiao jin, which results in fairly harmless
    behavior, and thus isn't marked for stable.
 
  - Xenia's patches to refactor the xHCI command handling code, which makes
    it much more readable and consistent.
 
  - Misc cleanup patches, one by Sachin Kamat and three from Dan Williams.
 
 Here's what's not in this request:
 
  - Dan's two patches to allow the xHCI host to use the "Windows" or "new"
    enumeration scheme.  I did not have time to test those, and I want to
    run them with as many USB devices as I can get a hold of.  That will
    have to wait for 3.14.
 
  - Xenia's patches to remove xhci_readl in favor of readl.  I'll queue
    those for 3.14 after I test them.
 
  - The xHCI streams update, UAS fixes, and usbfs streams support.  I'm not
    comfortable with changes and fixes to that patchset coming in this late.
    I would rather wait for 3.14 and be really sure the streams support is
    stable before we add new userspace API and remove CONFIG_BROKEN from the
    uas driver.
 
  - Julius' patch to clear the port reset bit on hub resume that came in
    a couple days ago.  It looks harmless, but I would rather take the time
    to test and queue it for usb-linus and the stable trees once 3.13-rc1
    is out.
 
 Sarah Sharp
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Merge tag 'for-usb-next-2013-10-17' of git://git.kernel.org/pub/scm/linux/kernel/git/sarah/xhci into usb-next

Sarah writes:

xhci: Final patches for 3.13

Hi Greg,

Here's my pull request for usb-next and 3.13.  My xHCI tree is closed
after this point, since I won't be able to run my full tests while I'm in
Scotland.  After Kernel Summit, I'll be on vacation with access to email
from Oct 26th to Nov 6th.

Here's what's in this request:

 - Patches to fix USB 2.0 Link PM issues that cause USB 3.0 devices to not
   enumerate or misbehave when plugged into a USB 2.0 port.  Those are
   marked for stable.

 - A msec vs jiffies bug fix by xiao jin, which results in fairly harmless
   behavior, and thus isn't marked for stable.

 - Xenia's patches to refactor the xHCI command handling code, which makes
   it much more readable and consistent.

 - Misc cleanup patches, one by Sachin Kamat and three from Dan Williams.

Here's what's not in this request:

 - Dan's two patches to allow the xHCI host to use the "Windows" or "new"
   enumeration scheme.  I did not have time to test those, and I want to
   run them with as many USB devices as I can get a hold of.  That will
   have to wait for 3.14.

 - Xenia's patches to remove xhci_readl in favor of readl.  I'll queue
   those for 3.14 after I test them.

 - The xHCI streams update, UAS fixes, and usbfs streams support.  I'm not
   comfortable with changes and fixes to that patchset coming in this late.
   I would rather wait for 3.14 and be really sure the streams support is
   stable before we add new userspace API and remove CONFIG_BROKEN from the
   uas driver.

 - Julius' patch to clear the port reset bit on hub resume that came in
   a couple days ago.  It looks harmless, but I would rather take the time
   to test and queue it for usb-linus and the stable trees once 3.13-rc1
   is out.

Sarah Sharp
2013-10-19 14:03:44 -07:00
xiao jin d194c03199 xhci: correct the usage of USB_CTRL_SET_TIMEOUT
The usage of USB_CTRL_SET_TIMEOUT in xhci is incorrect.
The definition of USB_CTRL_SET_TIMEOUT is 5000ms. The
input timeout to wait_for_completion_interruptible_timeout
is jiffies. That makes the timeout be longer than what
we want, such as 50s in some platform.

The patch is to use XHCI_CMD_DEFAULT_TIMEOUT instead of
USB_CTRL_SET_TIMEOUT as command completion event timeout.

Signed-off-by: xiao jin <jin.xiao@intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2013-10-16 12:24:23 -07:00
Sachin Kamat 5f20cf12a6 usb: xhci: Staticize xhci_del_comp_mod_timer
'xhci_del_comp_mod_timer' is local to this file.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2013-10-16 12:24:22 -07:00
Sarah Sharp f217c980ca xhci: Don't enable/disable RWE on bus suspend/resume.
The RWE bit of the USB 2.0 PORTPMSC register is supposed to enable
remote wakeup for devices in the lower power link state L1.  It has
nothing to do with the device suspend remote wakeup from L2.  The RWE
bit is designed to be set once (when USB 2.0 LPM is enabled for the
port) and cleared only when USB 2.0 LPM is disabled for the port.

The xHCI bus suspend method was setting the RWE bit erroneously, and the
bus resume method was clearing it.  The xHCI 1.0 specification with
errata up to Aug 12, 2012 says in section 4.23.5.1.1.1 "Hardware
Controlled LPM":

"While Hardware USB2 LPM is enabled, software shall not modify the
HIRDBESL or RWE fields of the USB2 PORTPMSC register..."

If we have previously enabled USB 2.0 LPM for a device, that means when
the USB 2.0 bus is resumed, we violate the xHCI specification by
clearing RWE.  It also means that after a bus resume, the host would
think remote wakeup is disabled from L1 for ports with USB 2.0 Link PM
enabled, which is not what we want.

This patch should be backported to kernels as old as 3.2, that
contain the commit 65580b4321 "xHCI: set
USB2 hardware LPM".  That was the first kernel that supported USB 2.0
Link PM.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
2013-10-09 16:26:55 -07:00
Sarah Sharp 8b3d45705e usb: Fix xHCI host issues on remote wakeup.
When a device signals remote wakeup on a roothub, and the suspend change
bit is set, the host controller driver must not give control back to the
USB core until the port goes back into the active state.

EHCI accomplishes this by waiting in the get port status function until
the PORT_RESUME bit is cleared:

                        /* stop resume signaling */
                        temp &= ~(PORT_RWC_BITS | PORT_SUSPEND | PORT_RESUME);
                        ehci_writel(ehci, temp, status_reg);
                        clear_bit(wIndex, &ehci->resuming_ports);
                        retval = ehci_handshake(ehci, status_reg,
                                        PORT_RESUME, 0, 2000 /* 2msec */);

Similarly, the xHCI host should wait until the port goes into U0, before
passing control up to the USB core.  When the port transitions from the
RExit state to U0, the xHCI driver will get a port status change event.
We need to wait for that event before passing control up to the USB
core.

After the port transitions to the active state, the USB core should time
a recovery interval before it talks to the device.  The length of that
recovery interval is TRSMRCY, 10 ms, mentioned in the USB 2.0 spec,
section 7.1.7.7.  The previous xHCI code (which did not wait for the
port to go into U0) would cause the USB core to violate that recovery
interval.

This bug caused numerous USB device disconnects on remote wakeup under
ChromeOS and a Lynx Point LP xHCI host that takes up to 20 ms to move
from RExit to U0.  ChromeOS is very aggressive about power savings, and
sets the autosuspend_delay to 100 ms, and disables USB persist.

I attempted to replicate this bug with Ubuntu 12.04, but could not.  I
used Ubuntu 12.04 on the same platform, with the same BIOS that the bug
was triggered on ChromeOS with.  I also changed the USB sysfs settings
as described above, but still could not reproduce the bug under Ubuntu.
It may be that ChromeOS userspace triggers this bug through additional
settings.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2013-09-23 15:43:31 -07:00
Mathias Nyman ec7e43e2d9 xhci: Ensure a command structure points to the correct trb on the command ring
If a command on the command ring needs to be cancelled before it is handled
it can be turned to a no-op operation when the ring is stopped.
We want to store the command ring enqueue pointer in the command structure
when the command in enqueued for the cancellation case.

Some commands used to store the command ring dequeue pointers instead of enqueue
(these often worked because enqueue happends to equal dequeue quite often)

Other commands correctly used the enqueue pointer but did not check if it pointed
to a valid trb or a link trb, this caused for example stop endpoint command to timeout in
xhci_stop_device() in about 2% of suspend/resume cases.

This should also solve some weird behavior happening in command cancellation cases.

This patch is based on a patch submitted by Sarah Sharp to linux-usb, but
then forgotten:
    http://marc.info/?l=linux-usb&m=136269803207465&w=2

This patch should be backported to kernels as old as 3.7, that contain
the commit b92cc66c04 "xHCI: add aborting
command ring function"

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
2013-09-23 15:43:30 -07:00
Xenia Ragiadakou 4bdfe4c38f xhci: add trace for debug messages related to quirks
This patch defines a new trace event, which is called xhci_dbg_quirks
and belongs in the event class xhci_log_msg, and adds tracepoints that
trace the debug messages associated with xHCs' quirks.

Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2013-08-13 16:05:41 -07:00
Sarah Sharp 063ebeb433 xhci: Report USB 2.1 link status for L1
USB 2.1 devices can go into a lower power link state, L1.  When they are
active, they are in the L0 state.  The L1 transition can be purely
driven by software, or some USB host controllers (including some xHCI
1.0 hosts) allow the host hardware to track idleness and automatically
place a port into L1.

The USB 2.1 Link Power Management ECN gives a way for USB 2.1 hubs that
support LPM to report that a port is in L1.  The port status bit 5 will
be set when the port is in L1.  The xHCI host reports the root port as
being in 'U2' when the devices is in L1, and as being in 'U0' when the
port is active (in L0).

Translate the xHCI USB 2.1 link status into the format external hubs
use, and pass the L1 status up to the USB core and tools like lsusb.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2013-07-23 14:19:19 -07:00
Sarah Sharp eae5b17621 xhci: Refactor port status into a new function.
The hub control function is *way* too long.  Refactor it into a new
function, and document the side effects of calling that function.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2013-07-23 14:19:19 -07:00
Mathias Nyman b6e76371c8 usb: xhci: define port register names and use them instead of magic numbers
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2013-06-05 16:47:21 -07:00
Alan Stern 84ebc10294 USB: remove CONFIG_USB_SUSPEND option
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: Alan Stern <stern@rowland.harvard.edu>
CC: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-28 11:10:22 -07:00
Sarah Sharp c52804a472 xhci: Avoid "dead ports", add roothub port polling.
The USB core hub thread (khubd) is designed with external USB hubs in
mind.  It expects that if a port status change bit is set, the hub will
continue to send a notification through the hub status data transfer.
Basically, it expects hub notifications to be level-triggered.

The xHCI host controller is designed to be edge-triggered on the logical
'OR' of all the port status change bits.  When all port status change
bits are clear, and a new change bit is set, the xHC will generate a
Port Status Change Event.  If another change bit is set in the same port
status register before the first bit is cleared, it will not send
another event.

This means that the hub code may lose port status changes because of
race conditions between clearing change bits.  The user sees this as a
"dead port" that doesn't react to device connects.

The fix is to turn on port polling whenever a new change bit is set.
Once the USB core issues a hub status request that shows that no change
bits are set in any USB ports, turn off port polling.

We can't allow the USB core to poll the roothub for port events during
host suspend because if the PCI host is in D3cold, the port registers
will be all f's.  Instead, stop the port polling timer, and
unconditionally restart it when the host resumes.  If there are no port
change bits set after the resume, the first call to hub_status_data will
disable polling.

This patch should be backported to stable kernels with the first xHCI
support, 2.6.31 and newer, that include the commit
0f2a79300a "USB: xhci: Root hub support."
There will be merge conflicts because the check for HC_STATE_SUSPENDED
was moved into xhci_suspend in 3.8.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable@vger.kernel.org
2013-01-03 14:10:29 -08:00
Sarah Sharp 41e7e056cd USB: Allow USB 3.0 ports to be disabled.
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 75d7cf72ab "usbcore: refine warm
reset logic"

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: John Covici <covici@ccs.covici.com>
Cc: stable@vger.kernel.org
2013-01-03 14:10:23 -08:00
Lan Tianyu 27c411c95a usb/xhci: Remove (__force__ __u16) before assigning DeviceRemovable and assign directly.
Struct usb_hub_descriptor.ss.DeviceRemovable has been defined as __le16
and (__force__ __u16) doesn't need.

Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-10-22 13:26:48 -07:00
Lan Tianyu 170ed80734 usb/xhci: release xhci->lock during turning on/off usb port's acpi power resource and checking the existence of port's power resource
When setting usb port's acpi power resource, there will be some xhci hub requests.
This will cause dead lock since xhci->lock has been held before setting acpi power
resource in the xhci_hub_control(). The usb_acpi_power_manageable() function might
fall into sleep so release xhci->lock before invoking it.

Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-10-22 13:26:48 -07:00
Greg Kroah-Hartman 2bcb132c69 Merge 3.6-rc6 into usb-next
This resolves the merge problems with:
	drivers/usb/dwc3/gadget.c
	drivers/usb/musb/tusb6010.c
that had been seen in linux-next.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-16 20:42:46 -07:00
Sebastian Andrzej Siewior 3415fc94bb usb/xhci: update a comment regarding the BOS descriptor to reflect the code
The comment is a quote of Alan Stern and reflects the data structure
better than the the initial comment.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-09-13 15:50:02 -07:00
Felipe Balbi ed384bd3a8 usb: host: xhci: sparse fixes
drivers/usb/host/xhci.c:1826:14: warning: symbol 'xhci_get_block_size' was not declared. Should it be static?
drivers/usb/host/xhci.c:1844:14: warning: symbol 'xhci_get_largest_overhead' was not declared. Should it be static?
drivers/usb/host/xhci-ring.c:2304:36: warning: context imbalance in 'handle_tx_event' - unexpected unlock
drivers/usb/host/xhci-hub.c:425:6: warning: symbol 'xhci_set_remote_wake_mask' was not declared. Should it be static?

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-09-13 15:50:01 -07:00
Lan Tianyu f7ac7787ad usb/acpi: Use ACPI methods to power off ports.
Upcoming Intel systems will have an ACPI method to control whether a USB
port can be completely powered off.  The implication of powering off a
USB port is that the device and host sees a physical disconnect, and
subsequent port connections and remote wakeups will be lost.

Add a new function, usb_acpi_power_manageable(), that can be used to
find whether the usb port has ACPI power resources that can be used to
power on and off the port on these machines. Also add a new function
called usb_acpi_set_power_state() that controls the port power via these
ACPI methods.

When the USB core calls into the xHCI hub driver to power off a port,
check whether the port can be completely powered off via this new ACPI
mechanism.  If so, call into these new ACPI methods.  Also use the ACPI
methods when the USB core asks to power on a port.

Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-10 13:04:01 -07:00
Lan Tianyu 693d8eb853 xhci: Handle clear PORT_POWER feature.
This patch makes the xHCI roothub code handle the clear PORT_POWER
feature request.  Setting port power is already handled.

Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-10 13:04:01 -07:00
Alexis R. Cortes 71c731a296 usb: host: xhci: Fix Compliance Mode on SN65LVPE502CP Hardware
This patch is intended to work around a known issue on the
SN65LVPE502CP USB3.0 re-driver that can delay the negotiation
between a device and the host past the usual handshake timeout.

If that happens on the first insertion, the host controller
port will enter in Compliance Mode and NO port status event will
be generated (as per xHCI Spec) making impossible to detect this
event by software. The port will remain in compliance mode until
a warm reset is applied to it.

As a result of this, the port will seem "dead" to the user and no
device connections or disconnections will be detected.

For solving this, the patch creates a timer which polls every 2
seconds the link state of each host controller's port (this
by reading the PORTSC register) and recovers the port by issuing a
Warm reset every time Compliance mode is detected.

If a xHC USB3.0 port has previously entered to U0, the compliance
mode issue will NOT occur only until system resumes from
sleep/hibernate, therefore, the compliance mode timer is stopped
when all xHC USB 3.0 ports have entered U0. The timer is initialized
again after each system resume.

Since the issue is being caused by a piece of hardware, the timer
will be enabled ONLY on those systems that have the SN65LVPE502CP
installed (this patch uses DMI strings for detecting those systems)
therefore making this patch to act as a quirk (XHCI_COMP_MODE_QUIRK
has been added to the xhci stack).

This patch applies for these systems:
Vendor: Hewlett-Packard. System Models: Z420, Z620 and Z820.

This patch should be backported to kernels as old as 3.2, as that was
the first kernel to support warm reset.  The kernels will need to
contain both commit 10d674a82e "USB: When
hot reset for USB3 fails, try warm reset" and commit
8bea2bd37d "usb: Add support for root hub
port status CAS".  The first patch add warm reset support, and the
second patch modifies the USB core to issue a warm reset when the port
is in compliance mode.

Signed-off-by: Alexis R. Cortes <alexis.cortes@ti.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
2012-09-05 12:07:18 -07:00
Greg Kroah-Hartman 6470cbc486 USB: Link PM fixes and Latency Tolerance Messaging
Hi Greg,
 
 Here's four bug fix patches for Link PM (LPM), which are marked for
 3.5-stable.  There's also three patches that turn on Latency Tolerance
 Messaging (LTM) for xHCI host controllers and USB 3.0 devices that support
 this low power feature.
 
 Please queue for 3.6.
 
 Sarah Sharp
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Merge tag 'for-usb-next-2012-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/sarah/xhci into usb-next

USB: Link PM fixes and Latency Tolerance Messaging

Hi Greg,

Here's four bug fix patches for Link PM (LPM), which are marked for
3.5-stable.  There's also three patches that turn on Latency Tolerance
Messaging (LTM) for xHCI host controllers and USB 3.0 devices that support
this low power feature.

Please queue for 3.6.

Sarah Sharp
2012-07-16 16:58:30 -07:00
Sarah Sharp af3a23ef4e xhci: Export Latency Tolerance Messaging capabilities.
Some xHCI host controllers may have optional support for Latency
Tolerance Messaging (LTM).  This allows USB 3.0 devices that support LTM
to pass information about how much latency they can tolerate to the xHC.
A PCI xHCI host will use this information to update the PCI Latency
Tolerance Request (LTR) info.  The goal of this is to gather latency
information for the system, to enable hardware-driven C states, and the
shutting down of PLLs.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-07-11 07:06:48 -04:00
Stanislaw Ledwon 8bea2bd37d usb: Add support for root hub port status CAS
The host controller port status register supports CAS (Cold Attach
Status) bit. This bit could be set when USB3.0 device is connected
when system is in Sx state. When the system wakes to S0 this port
status with CAS bit is reported and this port can't be used by any
device.

When CAS bit is set the port should be reset by warm reset. This
was not supported by xhci driver.

The issue was found when pendrive was connected to suspended
platform. The link state of "Compliance Mode" was reported together
with CAS bit. This link state was also not supported by xhci and
core/hub.c.

The CAS bit is defined only for xhci root hub port and it is
not supported on regular hubs. The link status is used to force
warm reset on port. Make the USB core issue a warm reset when port
is in ether the 'inactive' or 'compliance mode'. Change the xHCI driver
to report 'compliance mode' when the CAS is set. This force warm reset
on the root hub port.

This patch should be backported to stable kernels as old as 3.2, that
contain the commit 10d674a82e "USB: When
hot reset for USB3 fails, try warm reset."

Signed-off-by: Stanislaw Ledwon <staszek.ledwon@linux.intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: Andiry Xu <andiry.xu@amd.com>
Cc: stable@vger.kernel.org
2012-07-02 12:51:24 -07:00
Sarah Sharp 797b0ca5e6 xhci: Add roothub code to set U1/U2 timeouts.
USB 3.0 hubs can be put into a mode where the hub can automatically
request that the link go into a deeper link power state after the link
has been idle for a specified amount of time.  Each of the new USB 3.0
link states (U1 and U2) have their own timeout that can be programmed
per port.

Change the xHCI roothub emulation code to handle the request to set the
U1 and U2 timeouts.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-05-18 15:41:52 -07:00
Andiry Xu f370b9968a xHCI: keep track of ports being resumed and indicate in hub_status_data
This commit adds a bit-array to xhci bus_state for keeping track of
which ports are undergoing a resume transition. If any of the bits
are set when xhci_hub_status_data() is called, the routine will return
a non-zero value even if no ports have any status changes pending.
This will allow usbcore to handle races between root-hub suspend and
port wakeup.

This patch should be backported to kernels as old as 3.4, that contain
the commit 879d38e6bc "USB: fix race
between root-hub suspend and remote wakeup".

Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: stable@vger.kernel.org
2012-05-03 13:10:17 -07:00
Sarah Sharp 4296c70a5e USB/xHCI: Enable USB 3.0 hub remote wakeup.
USB 3.0 hubs have a different remote wakeup policy than USB 2.0 hubs.
USB 2.0 hubs, once they have remote wakeup enabled, will always send
remote wakes when anything changes on a port.

However, USB 3.0 hubs have a per-port remote wake up policy that is off
by default.  The Set Feature remote wake mask can be changed for any
port, enabling remote wakeup for a connect, disconnect, or overcurrent
event, much like EHCI and xHCI host controller "wake on" port status
bits.  The bits are cleared to zero on the initial hub power on, or
after the hub has been reset.

Without this patch, when a USB 3.0 hub gets suspended, it will not send
a remote wakeup on device connect or disconnect.  This would show up to
the user as "dead ports" unless they ran lsusb -v (since newer versions
of lsusb use the sysfs files, rather than sending control transfers).

Change the hub driver's suspend method to enable remote wake up for
disconnect, connect, and overcurrent for all ports on the hub.  Modify
the xHCI driver's roothub code to handle that request, and set the "wake
on" bits in the port status registers accordingly.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-02-14 12:12:24 -08:00
Sarah Sharp 3278a55a1a xhci: Fix oops caused by more USB2 ports than USB3 ports.
The code to set the device removable bits in the USB 2.0 roothub
descriptor was accidentally looking at the USB 3.0 port registers
instead of the USB 2.0 registers.  This can cause an oops if there are
more USB 2.0 registers than USB 3.0 registers.

This should be backported to kernels as old as 2.6.39, that contain the
commit 4bbb0ace9a "xhci: Return a USB 3.0
hub descriptor for USB3 roothub."

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
2012-02-10 14:24:32 -08:00
Aman Deep c842114792 xHCI: Adding #define values used for hub descriptor
xhci-hub used some numerical values for initialisation of root hub
descriptors. #define values are addded in usb 2.0 hub specification
file and these values are used for root hub characteristics
initialisation.

Also use some #defines in places where magic numbers are being used.

Signed-off-by: Aman Deep <amandeep3986@gmail.com>
Acked-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-11-26 19:58:47 -08:00
Paul Gortmaker 4bcbcc96e1 usb: fix implicit usage of gfp.h in host/xhci-hub.c
To fix this build error on ARM:

drivers/usb/host/xhci-hub.c: In function 'xhci_stop_device':
drivers/usb/host/xhci-hub.c:261: error: 'GFP_NOIO' undeclared (first use in this function)
make[4]: *** [drivers/usb/host/xhci-hub.o] Error 1

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:26 -04:00
Linus Torvalds 1be025d3cb Merge branch 'usb-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
* 'usb-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (260 commits)
  usb: renesas_usbhs: fixup inconsistent return from usbhs_pkt_push()
  usb/isp1760: Allow to optionally trigger low-level chip reset via GPIOLIB.
  USB: gadget: midi: memory leak in f_midi_bind_config()
  USB: gadget: midi: fix range check in f_midi_out_open()
  QE/FHCI: fixed the CONTROL bug
  usb: renesas_usbhs: tidyup for smatch warnings
  USB: Fix USB Kconfig dependency problem on 85xx/QoirQ platforms
  EHCI: workaround for MosChip controller bug
  usb: gadget: file_storage: fix race on unloading
  USB: ftdi_sio.c: Use ftdi async_icount structure for TIOCMIWAIT, as in other drivers
  USB: ftdi_sio.c:Fill MSR fields of the ftdi async_icount structure
  USB: ftdi_sio.c: Fill LSR fields of the ftdi async_icount structure
  USB: ftdi_sio.c:Fill TX field of the ftdi async_icount structure
  USB: ftdi_sio.c: Fill the RX field of the ftdi async_icount structure
  USB: ftdi_sio.c: Basic icount infrastructure for ftdi_sio
  usb/isp1760: Let OF bindings depend on general CONFIG_OF instead of PPC_OF .
  USB: ftdi_sio: Support TI/Luminary Micro Stellaris BD-ICDI Board
  USB: Fix runtime wakeup on OHCI
  xHCI/USB: Make xHCI driver have a BOS descriptor.
  usb: gadget: add new usb gadget for ACM and mass storage
  ...
2011-10-25 12:23:15 +02:00
Sarah Sharp 48e8236114 xHCI/USB: Make xHCI driver have a BOS descriptor.
To add USB 3.0 link power management (LPM), we need to know what the U1
and U2 exit latencies are for the xHCI host controller.  External USB 3.0
hubs report these values through the SuperSpeed Capabilities descriptor in
the BOS descriptor.  Make the USB 3.0 roothub for the xHCI host behave
like an external hub and return the BOS descriptors.

The U1 and U2 exit latencies will vary across each host controller, so we
need to dynamically fill those values in by reading the exit latencies out
of the xHC registers.  Make the roothub code in the USB core handle
hub_control() returning the length of the data copied.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-10-18 13:42:06 -07:00
Andiry Xu 65580b4321 xHCI: set USB2 hardware LPM
If the device pass the USB2 software LPM and the host supports hardware
LPM, enable hardware LPM for the device to let the host decide when to
put the link into lower power state.

If hardware LPM is enabled for a port and driver wants to put it into
suspend, it must first disable hardware LPM, resume the port into U0,
and then suspend the port.

Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-09-26 15:51:10 -07:00
Andiry Xu d2f52c9e58 xHCI: test and clear RWC bit
Introduce xhci_test_and_clear_bit() to clear RWC bit in PORTSC register.

Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-09-26 15:51:09 -07:00
Andiry Xu c9682dffce xHCI: set link state
Introduce xhci_set_link_state() to remove redundant codes.

Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-09-26 15:51:08 -07:00
Greg KH 44f4c3ed60 USB: xhci: Set change bit when warm reset change is set.
Sometimes, when a USB 3.0 device is disconnected, the Intel Panther
Point xHCI host controller will report a link state change with the
state set to "SS.Inactive".  This causes the xHCI host controller to
issue a warm port reset, which doesn't finish before the USB core times
out while waiting for it to complete.

When the warm port reset does complete, and the xHC gives back a port
status change event, the xHCI driver kicks khubd.  However, it fails to
set the bit indicating there is a change event for that port because the
logic in xhci-hub.c doesn't check for the warm port reset bit.

After that, the warm port status change bit is never cleared by the USB
core, and the xHC stops reporting port status change bits.  (The xHCI
spec says it shouldn't report more port events until all change bits are
cleared.) This means any port changes when a new device is connected
will never be reported, and the port will seem "dead" until the xHCI
driver is unloaded and reloaded, or the computer is rebooted.  Fix this
by making the xHCI driver set the port change bit when a warm port reset
change bit is set.

A better solution would be to make the USB core handle warm port reset
in differently, merging the current code with the standard port reset
code that does an incremental backoff on the timeout, and tries to
complete the port reset two more times before giving up.  That more
complicated fix will be merged next window, and this fix will be
backported to stable.

This should be backported to kernels as old as 3.0, since that was the
first kernel with commit a11496ebf3 ("xHCI: warm reset support").

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-19 17:15:46 -07:00
Sarah Sharp fe30182c25 xhci: Rename virt_dev->port to fake_port.
The "port" field in xhci_virt_dev stores the port number associated with
one of the two xHCI split roothubs, not the unique port number the xHCI
hardware uses.  Since we'll need to store the real hardware port number in
future patches, rename this field to "fake_port".

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-09-09 15:52:52 -07:00
Andiry Xu 8a8ff2f939 xHCI: report USB2 port in resuming as suspend
When a USB2 port initiate a remote wakeup, software shall ensure that
resume is signaled for at least 20ms, and then write '0' to the PLS field.
According to this, xhci driver do the following things:

1. When receive a remote wakeup event in irq_handler, set the resume_done
   value as jiffies + 20ms, and modify rh_timer to poll root hub status at
   that time;
2. When receive a GetPortStatus request, if the jiffies is after the
   resume_done value, clear the resume signal and resume_done.

However, if usb_port_resume() is called before the rh_timer triggered, it
will indicate the port as Suspend Cleared and skip the clear resume signal
part. The device will fail the usb_get_status request in finish_port_resume(),
and usbcore will try a reset-resume instead. Device will work OK after
reset-resume, but resume_done value is not cleared in this case, and
xhci_bus_suspend() will fail because when it finds a non-zero resume_done
value, it will regard the port as resuming and return -EBUSY.

This causes issue on some platforms that the system fail to suspend
after remote wakeup from suspend by USB2 devices connected to xHCI port.

To fix this issue, report the port status as suspend if the resume is
signaling less that 20ms, and usb_port_resume() will wait 25ms and check
port status again, so xHCI driver can clear the resume signaling and
resume_done value.

This should be backported to kernels as old as 2.6.37.

Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@kernel.org
2011-08-09 14:44:50 -07:00
Andiry Xu 5ac04bf190 xHCI: fix port U3 status check condition
Fix the port U3 status check when Clear PORT_SUSPEND Feature.
The port status should be masked with PORT_PLS_MASK to check if it's in
U3 state.

This should be backported to kernels as old as 2.6.37.

Signed-off-by: Andiry Xu <andiry.xu@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@kernel.org
2011-08-09 14:43:22 -07:00