This patch will improve the variable auto-resume latency of an usb-port.

The attempt to sync the start of root hub polling with resume time
signaling finish was ruined by a later request to start immediate
root hub polling.

When xhci gets a port status change event interrupt due to PORT_PLC
(port link state transition), linux Host controller driver drives the
resume signalling on the bus for the amount of time defined by
USB_REUME_TIMEOUT(40ms) macro.

This 40ms delay for resume signalling is in acceptable limit, but
it get worse when xhci goes for polling mode in order to detect other
events on its ports and modify rh_timer timer with a variable time out of
1ms to (HZ/4)ms.

drivers/usb/core/hcd.c line 799
mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4)).

Due to above variable timeout usb auto-resume latency varies from
40ms to ~300ms.

Log Snippet:
~128ms latency
[   53.112049] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0000
[   53.229200] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0004
[   53.240177] usb 1-2: usb wakeup-resume
[   53.240195] usb 1-2: finish resume
[   53.240357] usb usb1-port2: resume, status 0
-----------------------------------------------------------------
~300ms latency
[   59.946620] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0000
[   59.979341] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0000
[   60.229342] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0004
[   60.251321] usb 1-2: usb wakeup-resume
[   60.251335] usb 1-2: finish resume
[   60.251539] usb usb1-port2: resume, status 0

This variable resume latency can be optimized, as in case of PORT_PLC
change event rh_timer has already been modified with USB_RESUME_TIMEOUT
(40ms) delay,leaving the rest to GetPortStatus and started polling for
root hub status (invoking usb_hcd_poll_rh_status).
We can avoid polling as we have already modified rh_timer with
delay of 40ms.

This patch set the HCD_FLAG_POLL_RH to hcd->flags after modification of
rh_timer, and avoids polling of root hub status. so rh_timer can fire
after 40ms and usb device auto-resuem latency will be around 40ms.

[topic and first two senctences of commit message changed -Mathias]
Signed-off-by: NAnshuman Gupta <anshuman.gupta@intel.com>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Xhci driver handles USB transaction errors on transfer events,
but transaction errors are possible on address device command
completion events as well.

The xHCI specification (section 4.6.5) says: A USB Transaction
Error Completion Code for an Address Device Command may be due
to a Stall response from a device. Software should issue a Disable
Slot Command for the Device Slot then an Enable Slot Command to
recover from this error.

This patch handles USB transaction errors on address command
completion events. The related discussion threads can be found
through below links.

http://marc.info/?l=linux-usb&m=149362010728921&w=2
http://marc.info/?l=linux-usb&m=149252752825755&w=2Suggested-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

xhci->mutex was added in xhci_alloc_dev()  to protect two race sources
(xhci->slot_id and xhci->addr_dev) by commit a00918d0 ("usb: host:
xhci: add mutex for non-thread-safe data").

While xhci->slot_id has been discarded in commit c2d3d49b ("usb:
xhci: move slot_id from xhci_hcd to xhci_command structure"), and
xhci->addr_dev has been removed in commit 87e44f2a ("usb: xhci:
remove the use of xhci->addr_dev"), it's now safe to remove the use of
xhci->mutex in xhci_alloc_dev().

Link: https://marc.info/?l=linux-usb&m=150306294725821&w=2Suggested-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

xhci_disable_slot() is a helper for disabling a slot when a device
goes away or recovers from error situations. Currently, it returns
success when it sees a dead host. This is not the right way to go.
It should return error and let the invoker know that disable slot
command was failed due to a dead host.

Fixes: f9e609b8 ("usb: xhci: Add helper function xhci_disable_slot().")
Cc: Guoqing Zhang <guoqing.zhang@intel.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If xhci_disable_slot() returns success, a disable slot command
trb was queued in the command ring. The command completion
handler will free the virtual device data structure associated
with the slot. On the other hand, when xhci_disable_slot()
returns error, the invokers should take the responsibilities to
free the slot related data structure. Otherwise, memory leakage
happens.
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

xhci_disable_slot() allows the invoker to pass a command pointer
as paramenter. Otherwise, it will allocate one. This will cause
memory leak when a command structure was allocated inside of this
function while queuing command trb fails. Another problem comes up
when the invoker passed a command pointer, but xhci_disable_slot()
frees it when it detects a dead host.

This patch fixes these two problems by removing the command parameter
from xhci_disable_slot().

Fixes: f9e609b8 ("usb: xhci: Add helper function xhci_disable_slot().")
Cc: Guoqing Zhang <guoqing.zhang@intel.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

xhci_disable_slot() is a helper for disabling a slot when a device
goes away or recovers from error situations. Currently, it checks
the corespoding virt-dev pointer and returns directly (w/o issuing
disable slot command) if it's null.

This is unnecessary and will cause problems in case where virt-dev
allocation fails and xhci_disable_slot() is called to roll back the
hardware state. Refer to the implementation of xhci_alloc_dev().

This patch removes lines to check virt-dev in xhci_disable_slot().

Fixes: f9e609b8 ("usb: xhci: Add helper function xhci_disable_slot().")
Cc: Guoqing Zhang <guoqing.zhang@intel.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This adds debugfs consumer for xHCI driver. The debugfs entries
read all host registers, device/endpoint contexts, command ring,
event ring and various endpoint rings. With these entries, users
can check the registers and memory spaces used by a host during
run time, or save all the information with a simple 'cp -r' for
post-mortem programs.

The file hierarchy looks like this.

[root of debugfs]
|__usb
|____[e,u,o]hci                 <---------[root for other HCIs]
|____xhci                       <---------------[root for xHCI]
|______0000:00:14.0             <--------------[xHCI host name]
|________reg-cap                <--------[capability registers]
|________reg-op                 <-------[operational registers]
|________reg-runtime            <-----------[runtime registers]
|________reg-ext-#cap_name      <----[extended capability regs]
|________command-ring           <-------[root for command ring]
|__________cycle                <------------------[ring cycle]
|__________dequeue              <--------[ring dequeue pointer]
|__________enqueue              <--------[ring enqueue pointer]
|__________trbs                 <-------------------[ring trbs]
|________event-ring             <---------[root for event ring]
|__________cycle                <------------------[ring cycle]
|__________dequeue              <--------[ring dequeue pointer]
|__________enqueue              <--------[ring enqueue pointer]
|__________trbs                 <-------------------[ring trbs]
|________devices                <------------[root for devices]
|__________#slot_id             <-----------[root for a device]
|____________name               <-----------------[device name]
|____________slot-context       <----------------[slot context]
|____________ep-context         <-----------[endpoint contexts]
|____________ep#ep_index        <--------[root for an endpoint]
|______________cycle            <------------------[ring cycle]
|______________dequeue          <--------[ring dequeue pointer]
|______________enqueue          <--------[ring enqueue pointer]
|______________trbs             <-------------------[ring trbs]
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Shows the port speed protocol speed ID (PSID) in use.
speed ID may map to custom speeds, but in most cases it uses default

1 = Full-Speed        12 MB/s
2 = Low-Speed         1.5 Mb/s
3 = High-speed        480 Mb/s
4 = SuperSpeed        5 Gb/s
5 = SuperSpeedPlus    10 Gb/s
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

XHCI specification 1.1 does not require xHCI-compliant controllers
to always enable hardware USB2 LPM. However, the current xHCI
driver always enable it when seeing HLC=1.
This patch supports an option for users to control disabling
USB2 Hardware LPM via DT/ACPI attribute.
This option is needed in case user would like to disable this
feature. For example, their xHCI controller has its USB2 HW LPM
broken.
Signed-off-by: NTung Nguyen <tunguyen@apm.com>
Signed-off-by: NThang Q. Nguyen <tqnguyen@apm.com>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

   Use setup_timer function instead of initializing timer with the
   function and data fields.
Signed-off-by: NAllen Pais <allen.lkml@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

   Use setup_timer function instead of initializing timer with the
   function and data fields.
Signed-off-by: NAllen Pais <allen.lkml@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

   Use setup_timer function instead of initializing timer with the
   function and data fields.
Signed-off-by: NAllen Pais <allen.lkml@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

   Use setup_timer function instead of initializing timer with the
   function and data fields.
Signed-off-by: NAllen Pais <allen.lkml@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

   Use setup_timer function instead of initializing timer with the
   function and data fields.
Signed-off-by: NAllen Pais <allen.lkml@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

   Use setup_timer function instead of initializing timer with the
   function and data fields.
Signed-off-by: NAllen Pais <allen.lkml@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

   Use setup_timer function instead of initializing timer with the
   function and data fields.
Signed-off-by: NAllen Pais <allen.lkml@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

   Use setup_timer function instead of initializing timer with the
   function and data fields.
Signed-off-by: NAllen Pais <allen.lkml@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

   Use setup_timer function instead of initializing timer with the
   function and data fields.
Signed-off-by: NAllen Pais <allen.lkml@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When an Atmel SoC is suspended with the backup mode, the USB bus will be
powered down. As this is expected, do not return an error to the driver
core when ehci_resume detects it.
Signed-off-by: NRomain Izard <romain.izard.pro@gmail.com>
Acked-by: NNicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Remove the special SA1111 MMIO accessors from the ohci-sa1111 driver
as their definition will be removed shortly.  The SA1111 accessors are
barrierless, so use the _relaxed variants.
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Convert the shutdown method to use the device_driver shutdown function
pointer rather than a private bus-type shutdown.  This is the only user
for SA1111 bus types, so having the support code in the bus doesn't
make any sense.
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Use the provided sa1111_get_irq() to fetch the IRQ resources for the
SA1111 OHCI driver.
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Driver for TI TPS65982, TPS65983 and other TPS6598x family
stand alone USB Power Delivery controllers.

The driver will at this stage only register the port and
partners attached to it, so cables and alternate modes are
not yet registered. Both power and data role swapping is
supported.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch makes the driver work with USB Type-C Port
Manager (tcpm.c) to provide USB PD functionality.
Signed-off-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The .data assignment appears to be redundant to the WORK_STOP bit for
stopping the timer. Also, it appears this timer is entirely unused
as it is only ever started under #define VERBOSE, which is explicitly
undefined.
Signed-off-by: NKees Cook <keescook@chromium.org>
Acked-by: NFelipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Adds bindings documentation for the max3421 driver.
Signed-off-by: NJules Maselbas <jules.maselbas@grenoble-inp.org>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Adds support for devicetree to the max3421 driver.
Signed-off-by: NJules Maselbas <jules.maselbas@grenoble-inp.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

usbip_host_driver.h now depends on several additional headers, which
need to be installed along with it.

Fixes: 021aed84 ("staging: usbip: userspace: migrate usbip_host_driver ...")
Fixes: 3391ba0e ("usbip: tools: Extract generic code to be shared with ...")
Signed-off-by: NBen Hutchings <ben@decadent.org.uk>
Acked-by: NShuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Don't populate const arrays on the stack, instead make them
static.  Makes the object code smaller by over 1070 bytes:

Before:
   text	   data	    bss	    dec	    hex	filename
   3505	    880	      0	   4385	   1121	drivers/usb/storage/option_ms.o

After:
   text	   data	    bss	    dec	    hex	filename
   2269	   1040	      0	   3309	    ced	drivers/usb/storage/option_ms.o
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Make code more concise and readable
Signed-off-by: NHarsha Sharma <harshasharmaiitr@gmail.com>
Acked-by: NJulia Lawall <julia.lawall@lip6.fr>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The driver is in good enough shape to be moved out of staging.
Do it.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Move tcpm (USB Type-C Port Manager) out of staging.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

struct pd_message is the format of a PD message as seen on the wire.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Document struct tcpc_config and struct tcpc_dev.
Drop unused TCPC_USB_SWITCH_RESTORE.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Commented out code can be added as needed. Drop it.
Also drop TODO and an obsolete XXX comment.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Acked-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Pull UBI updates from Richard Weinberger:
 "Minor improvements"

* tag 'upstream-4.14-rc1' of git://git.infradead.org/linux-ubifs:
  UBI: Fix two typos in comments
  ubi: fastmap: fix spelling mistake: "invalidiate" -> "invalidate"
  ubi: pr_err() strings should end with newlines
  ubi: pr_err() strings should end with newlines
  ubi: pr_err() strings should end with newlines

Pull UML updates from Richard Weinberger:

 - minor improvements

 - fixes for Debian's new gcc defaults (pie enabled by default)

 - fixes for XSTATE/XSAVE to make UML work again on modern systems

* 'for-linus-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: return negative in tuntap_open_tramp()
  um: remove a stray tab
  um: Use relative modversions with LD_SCRIPT_DYN
  um: link vmlinux with -no-pie
  um: Fix CONFIG_GCOV for modules.
  Fix minor typos and grammar in UML start_up help
  um: defconfig: Cleanup from old Kconfig options
  um: Fix FP register size for XSTATE/XSAVE

Pull networking fixes from David Miller:

 1) Fix hotplug deadlock in hv_netvsc, from Stephen Hemminger.

 2) Fix double-free in rmnet driver, from Dan Carpenter.

 3) INET connection socket layer can double put request sockets, fix
    from Eric Dumazet.

 4) Don't match collect metadata-mode tunnels if the device is down,
    from Haishuang Yan.

 5) Do not perform TSO6/GSO on ipv6 packets with extensions headers in
    be2net driver, from Suresh Reddy.

 6) Fix scaling error in gen_estimator, from Eric Dumazet.

 7) Fix 64-bit statistics deadlock in systemport driver, from Florian
    Fainelli.

 8) Fix use-after-free in sctp_sock_dump, from Xin Long.

 9) Reject invalid BPF_END instructions in verifier, from Edward Cree.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (43 commits)
  mlxsw: spectrum_router: Only handle IPv4 and IPv6 events
  Documentation: link in networking docs
  tcp: fix data delivery rate
  bpf/verifier: reject BPF_ALU64|BPF_END
  sctp: do not mark sk dumped when inet_sctp_diag_fill returns err
  sctp: fix an use-after-free issue in sctp_sock_dump
  netvsc: increase default receive buffer size
  tcp: update skb->skb_mstamp more carefully
  net: ipv4: fix l3slave check for index returned in IP_PKTINFO
  net: smsc911x: Quieten netif during suspend
  net: systemport: Fix 64-bit stats deadlock
  net: vrf: avoid gcc-4.6 warning
  qed: remove unnecessary call to memset
  tg3: clean up redundant initialization of tnapi
  tls: make tls_sw_free_resources static
  sctp: potential read out of bounds in sctp_ulpevent_type_enabled()
  MAINTAINERS: review Renesas DT bindings as well
  net_sched: gen_estimator: fix scaling error in bytes/packets samples
  nfp: wait for the NSP resource to appear on boot
  nfp: wait for board state before talking to the NSP
  ...