<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/include/linux/usb, branch v3.12-rc2</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next</title>
<updated>2013-09-05T21:54:29+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2013-09-05T21:54:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=cc998ff8811530be521f6b316f37ab7676a07938'/>
<id>cc998ff8811530be521f6b316f37ab7676a07938</id>
<content type='text'>
Pull networking changes from David Miller:
 "Noteworthy changes this time around:

   1) Multicast rejoin support for team driver, from Jiri Pirko.

   2) Centralize and simplify TCP RTT measurement handling in order to
      reduce the impact of bad RTO seeding from SYN/ACKs.  Also, when
      both timestamps and local RTT measurements are available prefer
      the later because there are broken middleware devices which
      scramble the timestamp.

      From Yuchung Cheng.

   3) Add TCP_NOTSENT_LOWAT socket option to limit the amount of kernel
      memory consumed to queue up unsend user data.  From Eric Dumazet.

   4) Add a "physical port ID" abstraction for network devices, from
      Jiri Pirko.

   5) Add a "suppress" operation to influence fib_rules lookups, from
      Stefan Tomanek.

   6) Add a networking development FAQ, from Paul Gortmaker.

   7) Extend the information provided by tcp_probe and add ipv6 support,
      from Daniel Borkmann.

   8) Use RCU locking more extensively in openvswitch data paths, from
      Pravin B Shelar.

   9) Add SCTP support to openvswitch, from Joe Stringer.

  10) Add EF10 chip support to SFC driver, from Ben Hutchings.

  11) Add new SYNPROXY netfilter target, from Patrick McHardy.

  12) Compute a rate approximation for sending in TCP sockets, and use
      this to more intelligently coalesce TSO frames.  Furthermore, add
      a new packet scheduler which takes advantage of this estimate when
      available.  From Eric Dumazet.

  13) Allow AF_PACKET fanouts with random selection, from Daniel
      Borkmann.

  14) Add ipv6 support to vxlan driver, from Cong Wang"

Resolved conflicts as per discussion.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1218 commits)
  openvswitch: Fix alignment of struct sw_flow_key.
  netfilter: Fix build errors with xt_socket.c
  tcp: Add missing braces to do_tcp_setsockopt
  caif: Add missing braces to multiline if in cfctrl_linkup_request
  bnx2x: Add missing braces in bnx2x:bnx2x_link_initialize
  vxlan: Fix kernel panic on device delete.
  net: mvneta: implement -&gt;ndo_do_ioctl() to support PHY ioctls
  net: mvneta: properly disable HW PHY polling and ensure adjust_link() works
  icplus: Use netif_running to determine device state
  ethernet/arc/arc_emac: Fix huge delays in large file copies
  tuntap: orphan frags before trying to set tx timestamp
  tuntap: purge socket error queue on detach
  qlcnic: use standard NAPI weights
  ipv6:introduce function to find route for redirect
  bnx2x: VF RSS support - VF side
  bnx2x: VF RSS support - PF side
  vxlan: Notify drivers for listening UDP port changes
  net: usbnet: update addr_assign_type if appropriate
  driver/net: enic: update enic maintainers and driver
  driver/net: enic: Exposing symbols for Cisco's low latency driver
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull networking changes from David Miller:
 "Noteworthy changes this time around:

   1) Multicast rejoin support for team driver, from Jiri Pirko.

   2) Centralize and simplify TCP RTT measurement handling in order to
      reduce the impact of bad RTO seeding from SYN/ACKs.  Also, when
      both timestamps and local RTT measurements are available prefer
      the later because there are broken middleware devices which
      scramble the timestamp.

      From Yuchung Cheng.

   3) Add TCP_NOTSENT_LOWAT socket option to limit the amount of kernel
      memory consumed to queue up unsend user data.  From Eric Dumazet.

   4) Add a "physical port ID" abstraction for network devices, from
      Jiri Pirko.

   5) Add a "suppress" operation to influence fib_rules lookups, from
      Stefan Tomanek.

   6) Add a networking development FAQ, from Paul Gortmaker.

   7) Extend the information provided by tcp_probe and add ipv6 support,
      from Daniel Borkmann.

   8) Use RCU locking more extensively in openvswitch data paths, from
      Pravin B Shelar.

   9) Add SCTP support to openvswitch, from Joe Stringer.

  10) Add EF10 chip support to SFC driver, from Ben Hutchings.

  11) Add new SYNPROXY netfilter target, from Patrick McHardy.

  12) Compute a rate approximation for sending in TCP sockets, and use
      this to more intelligently coalesce TSO frames.  Furthermore, add
      a new packet scheduler which takes advantage of this estimate when
      available.  From Eric Dumazet.

  13) Allow AF_PACKET fanouts with random selection, from Daniel
      Borkmann.

  14) Add ipv6 support to vxlan driver, from Cong Wang"

Resolved conflicts as per discussion.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1218 commits)
  openvswitch: Fix alignment of struct sw_flow_key.
  netfilter: Fix build errors with xt_socket.c
  tcp: Add missing braces to do_tcp_setsockopt
  caif: Add missing braces to multiline if in cfctrl_linkup_request
  bnx2x: Add missing braces in bnx2x:bnx2x_link_initialize
  vxlan: Fix kernel panic on device delete.
  net: mvneta: implement -&gt;ndo_do_ioctl() to support PHY ioctls
  net: mvneta: properly disable HW PHY polling and ensure adjust_link() works
  icplus: Use netif_running to determine device state
  ethernet/arc/arc_emac: Fix huge delays in large file copies
  tuntap: orphan frags before trying to set tx timestamp
  tuntap: purge socket error queue on detach
  qlcnic: use standard NAPI weights
  ipv6:introduce function to find route for redirect
  bnx2x: VF RSS support - VF side
  bnx2x: VF RSS support - PF side
  vxlan: Notify drivers for listening UDP port changes
  net: usbnet: update addr_assign_type if appropriate
  driver/net: enic: update enic maintainers and driver
  driver/net: enic: Exposing symbols for Cisco's low latency driver
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'char-misc-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc</title>
<updated>2013-09-03T18:36:27+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2013-09-03T18:36:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=1d1fdd95df681f0c065d90ffaafa215a0e8825e2'/>
<id>1d1fdd95df681f0c065d90ffaafa215a0e8825e2</id>
<content type='text'>
Pull char/misc patches from Greg KH:
 "Here is the big char/misc driver pull request for 3.12-rc1

  Lots of driver updates all over the char/misc tree, full details in
  the shortlog"

* tag 'char-misc-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (62 commits)
  drivers: uio: Kconfig: add MMU dependancy for UIO
  drivers: uio: Add driver for Humusoft MF624 DAQ PCI card
  drivers: uio_pdrv_genirq: use dev_get_platdata()
  drivers: uio_pruss: use dev_get_platdata()
  drivers: uio_dmem_genirq: use dev_get_platdata()
  drivers: parport: Kconfig: exclude h8300 for PARPORT_PC
  drivers: misc: ti-st: fix potential race if st_kim_start fails
  Drivers: hv: vmbus: Do not attempt to negoatiate a new version prematurely
  misc: vmw_balloon: Remove braces to fix build for clang.
  Drivers: hv: vmbus: Fix a bug in the handling of channel offers
  vme: vme_ca91cx42.c: fix to pass correct device identity to free_irq()
  VMCI: Add support for virtual IOMMU
  VMCI: Remove non-blocking/pinned queuepair support
  uio: uio_pruss: remove unnecessary platform_set_drvdata()
  parport: amiga: remove unnecessary platform_set_drvdata()
  vme: vme_vmivme7805.c: add missing __iomem annotation
  vme: vme_ca91cx42.c: add missing __iomem annotation
  vme: vme_tsi148.c: add missing __iomem annotation
  drivers/misc/hpilo: Correct panic when an AUX iLO is detected
  uio: drop unused vma_count member in uio_device struct
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull char/misc patches from Greg KH:
 "Here is the big char/misc driver pull request for 3.12-rc1

  Lots of driver updates all over the char/misc tree, full details in
  the shortlog"

* tag 'char-misc-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (62 commits)
  drivers: uio: Kconfig: add MMU dependancy for UIO
  drivers: uio: Add driver for Humusoft MF624 DAQ PCI card
  drivers: uio_pdrv_genirq: use dev_get_platdata()
  drivers: uio_pruss: use dev_get_platdata()
  drivers: uio_dmem_genirq: use dev_get_platdata()
  drivers: parport: Kconfig: exclude h8300 for PARPORT_PC
  drivers: misc: ti-st: fix potential race if st_kim_start fails
  Drivers: hv: vmbus: Do not attempt to negoatiate a new version prematurely
  misc: vmw_balloon: Remove braces to fix build for clang.
  Drivers: hv: vmbus: Fix a bug in the handling of channel offers
  vme: vme_ca91cx42.c: fix to pass correct device identity to free_irq()
  VMCI: Add support for virtual IOMMU
  VMCI: Remove non-blocking/pinned queuepair support
  uio: uio_pruss: remove unnecessary platform_set_drvdata()
  parport: amiga: remove unnecessary platform_set_drvdata()
  vme: vme_vmivme7805.c: add missing __iomem annotation
  vme: vme_ca91cx42.c: add missing __iomem annotation
  vme: vme_tsi148.c: add missing __iomem annotation
  drivers/misc/hpilo: Correct panic when an AUX iLO is detected
  uio: drop unused vma_count member in uio_device struct
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>USB: fix build error when CONFIG_PM_SLEEP isn't enabled</title>
<updated>2013-08-30T18:12:06+00:00</updated>
<author>
<name>Alan Stern</name>
<email>stern@rowland.harvard.edu</email>
</author>
<published>2013-08-30T14:46:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9d8924297cd9c256c23c02abae40202563452453'/>
<id>9d8924297cd9c256c23c02abae40202563452453</id>
<content type='text'>
This patch fixes a build error that occurs when CONFIG_PM is enabled
and CONFIG_PM_SLEEP isn't:

&gt;&gt; drivers/usb/host/ohci-pci.c:294:10: error: 'usb_hcd_pci_pm_ops' undeclared here (not in a function)
      .pm = &amp;usb_hcd_pci_pm_ops

Since the usb_hcd_pci_pm_ops structure is defined and used when
CONFIG_PM is enabled, its declaration should not be protected by
CONFIG_PM_SLEEP.

Signed-off-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Reported-by: kbuild test robot &lt;fengguang.wu@intel.com&gt;
CC: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch fixes a build error that occurs when CONFIG_PM is enabled
and CONFIG_PM_SLEEP isn't:

&gt;&gt; drivers/usb/host/ohci-pci.c:294:10: error: 'usb_hcd_pci_pm_ops' undeclared here (not in a function)
      .pm = &amp;usb_hcd_pci_pm_ops

Since the usb_hcd_pci_pm_ops structure is defined and used when
CONFIG_PM is enabled, its declaration should not be protected by
CONFIG_PM_SLEEP.

Signed-off-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Reported-by: kbuild test robot &lt;fengguang.wu@intel.com&gt;
CC: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>USB: WUSBCORE: clear RPIPE stall for control endpoints</title>
<updated>2013-08-16T00:35:31+00:00</updated>
<author>
<name>Thomas Pugliese</name>
<email>thomas.pugliese@gmail.com</email>
</author>
<published>2013-08-15T17:21:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=6d33f7bb8c3863e54f8bdede0a2bf97a3585ac20'/>
<id>6d33f7bb8c3863e54f8bdede0a2bf97a3585ac20</id>
<content type='text'>
When the HWA encounters a STALL on a control endpoint, it should clear the
RPIPE_STALL feature on the RPIPE before processing the next transfer
request.  Otherwise, all transfer requests on that endpoint after the
first STALL will fail because the RPIPE is still in the halted state.
This also removes the unneccessary call to spin_lock_irqsave for a nested
lock that was present in the first patch.

Signed-off-by: Thomas Pugliese &lt;thomas.pugliese@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When the HWA encounters a STALL on a control endpoint, it should clear the
RPIPE_STALL feature on the RPIPE before processing the next transfer
request.  Otherwise, all transfer requests on that endpoint after the
first STALL will fail because the RPIPE is still in the halted state.
This also removes the unneccessary call to spin_lock_irqsave for a nested
lock that was present in the first patch.

Signed-off-by: Thomas Pugliese &lt;thomas.pugliese@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: chipidea: retire flag CI_HDRC_PULLUP_ON_VBUS</title>
<updated>2013-08-14T19:37:20+00:00</updated>
<author>
<name>Peter Chen</name>
<email>peter.chen@freescale.com</email>
</author>
<published>2013-08-14T09:44:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d268e9bc23f5df4a2f4167da246d277c2a468d3d'/>
<id>d268e9bc23f5df4a2f4167da246d277c2a468d3d</id>
<content type='text'>
Currently, the controller only runs when the ci-&gt;vbus_active is true.
So the flag CI_HDRC_PULLUP_ON_VBUS is useless no longer.
If the user doesn't have otgsc, he/she needs to change ci_handle_vbus_change
to update ci-&gt;vbus_active.

Signed-off-by: Peter Chen &lt;peter.chen@freescale.com&gt;
Signed-off-by: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently, the controller only runs when the ci-&gt;vbus_active is true.
So the flag CI_HDRC_PULLUP_ON_VBUS is useless no longer.
If the user doesn't have otgsc, he/she needs to change ci_handle_vbus_change
to update ci-&gt;vbus_active.

Signed-off-by: Peter Chen &lt;peter.chen@freescale.com&gt;
Signed-off-by: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: chipidea: add flag CI_HDRC_DUAL_ROLE_NOT_OTG</title>
<updated>2013-08-14T19:37:19+00:00</updated>
<author>
<name>Peter Chen</name>
<email>peter.chen@freescale.com</email>
</author>
<published>2013-08-14T09:44:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=577b232fc9caba1b6f7a3bb9901c00b10e0ca1ba'/>
<id>577b232fc9caba1b6f7a3bb9901c00b10e0ca1ba</id>
<content type='text'>
Since we need otgsc to know vbus's status at some chipidea
controllers even it is peripheral-only mode. Besides, some
SoCs (eg, AR9331 SoC) don't have otgsc register even
the DCCPARAMS_DC and DCCPARAMS_HC are both 1 at CAP_DCCPARAMS.

We inroduce flag CI_HDRC_DUAL_ROLE_NOT_OTG to indicate if the
controller is dual role, but not supports OTG. If this flag is
not set, we follow the rule that if DCCPARAMS_DC and DCCPARAMS_HC
are both 1 at CAP_DCCPARAMS, then this controller is otg capable.

Signed-off-by: Peter Chen &lt;peter.chen@freescale.com&gt;
Signed-off-by: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Since we need otgsc to know vbus's status at some chipidea
controllers even it is peripheral-only mode. Besides, some
SoCs (eg, AR9331 SoC) don't have otgsc register even
the DCCPARAMS_DC and DCCPARAMS_HC are both 1 at CAP_DCCPARAMS.

We inroduce flag CI_HDRC_DUAL_ROLE_NOT_OTG to indicate if the
controller is dual role, but not supports OTG. If this flag is
not set, we follow the rule that if DCCPARAMS_DC and DCCPARAMS_HC
are both 1 at CAP_DCCPARAMS, then this controller is otg capable.

Signed-off-by: Peter Chen &lt;peter.chen@freescale.com&gt;
Signed-off-by: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>usb: chipidea: move vbus regulator operation to core</title>
<updated>2013-08-14T19:34:17+00:00</updated>
<author>
<name>Peter Chen</name>
<email>peter.chen@freescale.com</email>
</author>
<published>2013-08-14T09:44:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=1542d9c35d8166c54e0616574954a0f48449f331'/>
<id>1542d9c35d8166c54e0616574954a0f48449f331</id>
<content type='text'>
The vbus regulator is a common element for USB vbus operation,
So, move it from glue layer to core.

Tested-by: Marek Vasut &lt;marex@denx.de&gt;
Signed-off-by: Michael Grzeschik &lt;m.grzeschik@pengutronix.de&gt;
Signed-off-by: Peter Chen &lt;peter.chen@freescale.com&gt;
Signed-off-by: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The vbus regulator is a common element for USB vbus operation,
So, move it from glue layer to core.

Tested-by: Marek Vasut &lt;marex@denx.de&gt;
Signed-off-by: Michael Grzeschik &lt;m.grzeschik@pengutronix.de&gt;
Signed-off-by: Peter Chen &lt;peter.chen@freescale.com&gt;
Signed-off-by: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'usb-for-v3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-next</title>
<updated>2013-08-13T22:28:01+00:00</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2013-08-13T22:28:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=165f60642ae988f0b9dcfd4988806e7a938b26c7'/>
<id>165f60642ae988f0b9dcfd4988806e7a938b26c7</id>
<content type='text'>
Felipe writes:

usb: patches for v3.12 merge window

All patches here have been pending on linux-usb
and sitting in linux-next for a while now.

The biggest things in this tag are:

DWC3 learned proper usage of threaded IRQ
handlers and now we spend very little time
in hardirq context.

MUSB now has proper support for BeagleBone and
Beaglebone Black.

Tegra's USB support also got quite a bit of love
and is learning to use PHY layer and generic DT
attributes.

Other than that, the usual pack of cleanups and
non-critical fixes follow.

Signed-of-by: Felipe Balbi &lt;balbi@ti.com&gt;

Conflicts:
	drivers/usb/gadget/udc-core.c
	drivers/usb/host/ehci-tegra.c
	drivers/usb/musb/omap2430.c
	drivers/usb/musb/tusb6010.c
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Felipe writes:

usb: patches for v3.12 merge window

All patches here have been pending on linux-usb
and sitting in linux-next for a while now.

The biggest things in this tag are:

DWC3 learned proper usage of threaded IRQ
handlers and now we spend very little time
in hardirq context.

MUSB now has proper support for BeagleBone and
Beaglebone Black.

Tegra's USB support also got quite a bit of love
and is learning to use PHY layer and generic DT
attributes.

Other than that, the usual pack of cleanups and
non-critical fixes follow.

Signed-of-by: Felipe Balbi &lt;balbi@ti.com&gt;

Conflicts:
	drivers/usb/gadget/udc-core.c
	drivers/usb/host/ehci-tegra.c
	drivers/usb/musb/omap2430.c
	drivers/usb/musb/tusb6010.c
</pre>
</div>
</content>
</entry>
<entry>
<title>USBNET: support DMA SG</title>
<updated>2013-08-12T19:09:23+00:00</updated>
<author>
<name>Ming Lei</name>
<email>ming.lei@canonical.com</email>
</author>
<published>2013-08-08T13:48:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=638c5115a794981441246fa8fa5d95c1875af5ba'/>
<id>638c5115a794981441246fa8fa5d95c1875af5ba</id>
<content type='text'>
This patch introduces support of DMA SG if the USB host controller
which usbnet device is attached to is capable of building packet from
discontinuous buffers.

The patch supports passing the skb fragment buffers to usb stack directly
via urb-&gt;sg.

Cc: Ben Hutchings &lt;bhutchings@solarflare.com&gt;
Cc: Grant Grundler &lt;grundler@google.com&gt;
Cc: Freddy Xin &lt;freddy@asix.com.tw&gt;
Cc: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Acked-by: Oliver Neukum &lt;oneukum@suse.de&gt;
Signed-off-by: Ming Lei &lt;ming.lei@canonical.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Acked-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch introduces support of DMA SG if the USB host controller
which usbnet device is attached to is capable of building packet from
discontinuous buffers.

The patch supports passing the skb fragment buffers to usb stack directly
via urb-&gt;sg.

Cc: Ben Hutchings &lt;bhutchings@solarflare.com&gt;
Cc: Grant Grundler &lt;grundler@google.com&gt;
Cc: Freddy Xin &lt;freddy@asix.com.tw&gt;
Cc: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Acked-by: Oliver Neukum &lt;oneukum@suse.de&gt;
Signed-off-by: Ming Lei &lt;ming.lei@canonical.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Acked-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>USB: HCD: support giveback of URB in tasklet context</title>
<updated>2013-08-12T18:43:48+00:00</updated>
<author>
<name>Ming Lei</name>
<email>ming.lei@canonical.com</email>
</author>
<published>2013-07-03T14:53:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=94dfd7edfd5c9b605caf7b562de7a813d216e011'/>
<id>94dfd7edfd5c9b605caf7b562de7a813d216e011</id>
<content type='text'>
This patch implements the mechanism of giveback of URB in
tasklet context, so that hardware interrupt handling time for
usb host controller can be saved much, and HCD interrupt handling
can be simplified.

Motivations:

1), on some arch(such as ARM), DMA mapping/unmapping is a bit
time-consuming, for example: when accessing usb mass storage
via EHCI on pandaboard, the common length of transfer buffer is 120KB,
the time consumed on DMA unmapping may reach hundreds of microseconds;
even on A15 based box, the time is still about scores of microseconds

2), on some arch, reading DMA coherent memoery is very time-consuming,
the most common example is usb video class driver[1]

3), driver's complete() callback may do much things which is driver
specific, so the time is consumed unnecessarily in hardware irq context.

4), running driver's complete() callback in hardware irq context causes
that host controller driver has to release its lock in interrupt handler,
so reacquiring the lock after return may busy wait a while and increase
interrupt handling time. More seriously, releasing the HCD lock makes
HCD becoming quite complicated to deal with introduced races.

So the patch proposes to run giveback of URB in tasklet context, then
time consumed in HCD irq handling doesn't depend on drivers' complete and
DMA mapping/unmapping any more, also we can simplify HCD since the HCD
lock isn't needed to be released during irq handling.

The patch should be reasonable and doable:

1), for drivers, they don't care if the complete() is called in hard irq
context or softirq context

2), the biggest change is the situation in which usb_submit_urb() is called
in complete() callback, so the introduced tasklet schedule delay might be a
con, but it shouldn't be a big deal:

	- control/bulk asynchronous transfer isn't sensitive to schedule
	  delay

	- the patch schedules giveback of periodic URBs using
	  tasklet_hi_schedule, so the introduced delay should be very
	  small

	- for ISOC transfer, generally, drivers submit several URBs
	  concurrently to avoid interrupt delay, so it is OK with the
	  little schedule delay.

	- for interrupt transfer, generally, drivers only submit one URB
	  at the same time, but interrupt transfer is often used in event
	  report, polling, ... situations, and a little delay should be OK.

Considered that HCDs may optimize on submitting URB in complete(), the
patch may cause the optimization not working, so introduces one flag to mark
if the HCD supports to run giveback URB in tasklet context. When all HCDs
are ready, the flag can be removed.

[1], http://marc.info/?t=136438111600010&amp;r=1&amp;w=2

Cc: Oliver Neukum &lt;oliver@neukum.org&gt;
Acked-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Signed-off-by: Ming Lei &lt;ming.lei@canonical.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch implements the mechanism of giveback of URB in
tasklet context, so that hardware interrupt handling time for
usb host controller can be saved much, and HCD interrupt handling
can be simplified.

Motivations:

1), on some arch(such as ARM), DMA mapping/unmapping is a bit
time-consuming, for example: when accessing usb mass storage
via EHCI on pandaboard, the common length of transfer buffer is 120KB,
the time consumed on DMA unmapping may reach hundreds of microseconds;
even on A15 based box, the time is still about scores of microseconds

2), on some arch, reading DMA coherent memoery is very time-consuming,
the most common example is usb video class driver[1]

3), driver's complete() callback may do much things which is driver
specific, so the time is consumed unnecessarily in hardware irq context.

4), running driver's complete() callback in hardware irq context causes
that host controller driver has to release its lock in interrupt handler,
so reacquiring the lock after return may busy wait a while and increase
interrupt handling time. More seriously, releasing the HCD lock makes
HCD becoming quite complicated to deal with introduced races.

So the patch proposes to run giveback of URB in tasklet context, then
time consumed in HCD irq handling doesn't depend on drivers' complete and
DMA mapping/unmapping any more, also we can simplify HCD since the HCD
lock isn't needed to be released during irq handling.

The patch should be reasonable and doable:

1), for drivers, they don't care if the complete() is called in hard irq
context or softirq context

2), the biggest change is the situation in which usb_submit_urb() is called
in complete() callback, so the introduced tasklet schedule delay might be a
con, but it shouldn't be a big deal:

	- control/bulk asynchronous transfer isn't sensitive to schedule
	  delay

	- the patch schedules giveback of periodic URBs using
	  tasklet_hi_schedule, so the introduced delay should be very
	  small

	- for ISOC transfer, generally, drivers submit several URBs
	  concurrently to avoid interrupt delay, so it is OK with the
	  little schedule delay.

	- for interrupt transfer, generally, drivers only submit one URB
	  at the same time, but interrupt transfer is often used in event
	  report, polling, ... situations, and a little delay should be OK.

Considered that HCDs may optimize on submitting URB in complete(), the
patch may cause the optimization not working, so introduces one flag to mark
if the HCD supports to run giveback URB in tasklet context. When all HCDs
are ready, the flag can be removed.

[1], http://marc.info/?t=136438111600010&amp;r=1&amp;w=2

Cc: Oliver Neukum &lt;oliver@neukum.org&gt;
Acked-by: Alan Stern &lt;stern@rowland.harvard.edu&gt;
Signed-off-by: Ming Lei &lt;ming.lei@canonical.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
