Searched +hist:9 +hist:b790915 (Results 1 - 3 of 3) sorted by relevance

/linux-master/drivers/usb/host/
H A Dehci-hub.cdiff 9d4b8270 Mon Nov 28 22:45:38 MST 2016 Changming Huang <jerry.huang@nxp.com> fsl/usb: Workarourd for USB erratum-A005697

The EHCI specification states the following in the SUSP bit description:
In the Suspend state, the port is sensitive to resume detection.
Note that the bit status does not change until the port is suspended and
that there may be a delay in suspending a port if there is a transaction
currently in progress on the USB.

However, in NXP USBDR controller, the PORTSCx[SUSP] bit changes immediately
when the application sets it and not when the port is actually suspended.

So the application must wait for at least 10 milliseconds after a port
indicates that it is suspended, to make sure this port has entered
suspended state before initiating this port resume using the Force Port
Resume bit. This bit is for NXP controller, not EHCI compatible.

Signed-off-by: Changming Huang <jerry.huang@nxp.com>
Signed-off-by: Ramneek Mehresh <ramneek.mehresh@nxp.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 9b790915 Fri May 17 01:08:51 MDT 2013 Julius Werner <jwerner@chromium.org> usb: ehci: Only sleep for post-resume handover if devices use persist

The current EHCI code sleeps a flat 110ms in the resume path if there
was a USB 1.1 device connected to its companion controller during
suspend, waiting for the device to reappear and reset so that it can be
handed back to the companion. This is necessary if the device uses
persist, so that the companion controller can actually see it during its
own resume path.

However, if the device doesn't use persist, this is entirely
unnecessary. We might just as well ignore it and have the normal device
detection/reset/handoff code handle it asynchronously when it eventually
shows up. As USB 1.1 devices are almost exclusively HIDs these days (for
which persist has no value), this can allow distros to shave another
tenth of a second off their resume time.

In order to enable this optimization, the patch also adds a new
usb_for_each_dev() iterator that is exported by the USB core and wraps
bus_for_each_dev() with the logic to differentiate between struct
usb_device and struct usb_interface on the usb_bus_type bus.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 9b790915 Fri May 17 01:08:51 MDT 2013 Julius Werner <jwerner@chromium.org> usb: ehci: Only sleep for post-resume handover if devices use persist

The current EHCI code sleeps a flat 110ms in the resume path if there
was a USB 1.1 device connected to its companion controller during
suspend, waiting for the device to reappear and reset so that it can be
handed back to the companion. This is necessary if the device uses
persist, so that the companion controller can actually see it during its
own resume path.

However, if the device doesn't use persist, this is entirely
unnecessary. We might just as well ignore it and have the normal device
detection/reset/handoff code handle it asynchronously when it eventually
shows up. As USB 1.1 devices are almost exclusively HIDs these days (for
which persist has no value), this can allow distros to shave another
tenth of a second off their resume time.

In order to enable this optimization, the patch also adds a new
usb_for_each_dev() iterator that is exported by the USB core and wraps
bus_for_each_dev() with the logic to differentiate between struct
usb_device and struct usb_interface on the usb_bus_type bus.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 9fa5780b Mon Sep 17 17:23:02 MDT 2012 Jan Beulich <JBeulich@suse.com> USB EHCI/Xen: propagate controller reset information to hypervisor

Just like for the in-tree early console debug port driver, the
hypervisor - when using a debug port based console - also needs to be
told about controller resets, so it can suppress using and then
re-initialize the debug port accordingly.

Other than the in-tree driver, the hypervisor driver actually cares
about doing this only for the device where the debug is port actually
in use, i.e. it needs to be told the coordinates of the device being
reset (quite obviously, leveraging the addition done for that would
likely benefit the in-tree driver too).

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 9d938747 Wed Jul 11 09:22:44 MDT 2012 Alan Stern <stern@rowland.harvard.edu> USB: EHCI: use hrtimer for the IAA watchdog

This patch (as1581) replaces the iaa_watchdog kernel timer used by
ehci-hcd with an hrtimer event, in keeping with the general conversion
to high-res timers.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff df202255 Wed Jul 11 09:22:26 MDT 2012 Alan Stern <stern@rowland.harvard.edu> USB: EHCI: use hrtimer for interrupt QH unlink

This patch (as1577) adds hrtimer support for unlinking interrupt QHs
in ehci-hcd. The current code relies on a fixed delay of either 2 or
55 us, which is not always adequate and in any case is totally bogus.
Thanks to internal caching, the EHCI hardware may continue to access
an interrupt QH for more than a millisecond after it has been unlinked.

In fact, the EHCI spec doesn't say how long to wait before using an
unlinked interrupt QH. The patch sets the delay to 9 microframes
minimum, which ought to be adequate.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
/linux-master/drivers/usb/core/
H A Dusb.cdiff 5198c0ee Fri Aug 11 09:47:15 MDT 2023 Alan Stern <stern@rowland.harvard.edu> USB: core: Fix unused variable warning in usb_alloc_dev()

The kernel test robot reported that a recent commit caused a "variable
set but not used" warning. As a result of that commit, the variable
no longer serves any purpose; it should be removed.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202308092350.HR4PVHUt-lkp@intel.com/
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Fixes: 1e4c574225cc ("USB: Remove remnants of Wireless USB and UWB")
Link: https://lore.kernel.org/r/7223cc66-f006-42ae-9f30-a6c546bf97a7@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 9c174b57 Tue Feb 16 03:14:32 MST 2021 Greg Kroah-Hartman <gregkh@linuxfoundation.org> USB: core: no need to save usb_devices_root

There is no need to save the usb_devices debugfs file as we only need it
when removing it, so have the debugfs code look it up when it is needed
instead, saving the storage.

Link: https://lore.kernel.org/r/YCubCA/trHAF7PtF@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 9be427ef Mon May 02 07:35:57 MDT 2016 Johan Hovold <johan@kernel.org> Revert "USB / PM: Allow USB devices to remain runtime-suspended when sleeping"

This reverts commit e3345db85068ddb937fc0ba40dfc39c293dad977, which
broke system resume for a large class of devices.

Devices that after having been reset during resume need to be rebound
due to a missing reset_resume callback, are now left in a suspended
state. This specifically broke resume of common USB-serial devices,
which are now unusable after system suspend (until disconnected and
reconnected) when USB persist is enabled.

During resume, usb_resume_interface will set the needs_binding flag for
such interfaces, but unlike system resume, run-time resume does not
honour it.

Cc: stable <stable@vger.kernel.org> # 4.5
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 9b790915 Fri May 17 01:08:51 MDT 2013 Julius Werner <jwerner@chromium.org> usb: ehci: Only sleep for post-resume handover if devices use persist

The current EHCI code sleeps a flat 110ms in the resume path if there
was a USB 1.1 device connected to its companion controller during
suspend, waiting for the device to reappear and reset so that it can be
handed back to the companion. This is necessary if the device uses
persist, so that the companion controller can actually see it during its
own resume path.

However, if the device doesn't use persist, this is entirely
unnecessary. We might just as well ignore it and have the normal device
detection/reset/handoff code handle it asynchronously when it eventually
shows up. As USB 1.1 devices are almost exclusively HIDs these days (for
which persist has no value), this can allow distros to shave another
tenth of a second off their resume time.

In order to enable this optimization, the patch also adds a new
usb_for_each_dev() iterator that is exported by the USB core and wraps
bus_for_each_dev() with the logic to differentiate between struct
usb_device and struct usb_interface on the usb_bus_type bus.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 9b790915 Fri May 17 01:08:51 MDT 2013 Julius Werner <jwerner@chromium.org> usb: ehci: Only sleep for post-resume handover if devices use persist

The current EHCI code sleeps a flat 110ms in the resume path if there
was a USB 1.1 device connected to its companion controller during
suspend, waiting for the device to reappear and reset so that it can be
handed back to the companion. This is necessary if the device uses
persist, so that the companion controller can actually see it during its
own resume path.

However, if the device doesn't use persist, this is entirely
unnecessary. We might just as well ignore it and have the normal device
detection/reset/handoff code handle it asynchronously when it eventually
shows up. As USB 1.1 devices are almost exclusively HIDs these days (for
which persist has no value), this can allow distros to shave another
tenth of a second off their resume time.

In order to enable this optimization, the patch also adds a new
usb_for_each_dev() iterator that is exported by the USB core and wraps
bus_for_each_dev() with the logic to differentiate between struct
usb_device and struct usb_interface on the usb_bus_type bus.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 9cf65991 Wed Jul 04 00:22:38 MDT 2012 Sarah Sharp <sarah.a.sharp@linux.intel.com> USB: Disable LPM while the device is unconfigured.

The USB 3.0 Set/Clear Feature U1/U2 Enable cannot be sent to a device in
the Default or Addressed state. It can only be sent to a configured
device. Change the USB core to initialize the LPM disable count to 1
(disabled), which reflects this limitation.

Change usb_set_configuration() to ensure that if the device is
unconfigured on entry, usb_lpm_disable() is not called. This avoids
sending the Clear Feature U1/U2 when the device is in the Addressed
state. When usb_set_configuration() exits with a successfully installed
configuration, usb_lpm_enable() will be called.

Once the new configuration is installed, make sure
usb_set_configuration() only calls usb_enable_lpm() if the device moved
to the Configured state. If we have unconfigured the device by sending
it a Set Configuration for config 0, don't enable LPM.

This commit should be backported to kernels as old as 3.5, that contain
the commit 8306095fd2c1100e8244c09bf560f97aca5a311d "USB: Disable USB
3.0 LPM in critical sections."

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
diff 9bbdf1e0 Thu Jan 07 22:57:28 MST 2010 Alan Stern <stern@rowland.harvard.edu> USB: convert to the runtime PM framework

This patch (as1329) converts the USB stack over to the PM core's
runtime PM framework. This involves numerous changes throughout
usbcore, especially to hub.c and driver.c. Perhaps the most notable
change is that CONFIG_USB_SUSPEND now depends on CONFIG_PM_RUNTIME
instead of CONFIG_PM.

Several fields in the usb_device and usb_interface structures are no
longer needed. Some code which used to depend on CONFIG_USB_PM now
depends on CONFIG_USB_SUSPEND (requiring some rearrangement of header
files).

The only visible change in behavior should be that following a system
sleep (resume from RAM or resume from hibernation), autosuspended USB
devices will be resumed just like everything else. They won't remain
suspended. But if they aren't in use then they will naturally
autosuspend again in a few seconds.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff 7206b001 Mon Apr 27 20:54:49 MDT 2009 Sarah Sharp <sarah.a.sharp@linux.intel.com> USB: Add route string to struct usb_device.

This patch adds a hex route string to each USB device. The route string is used
by the USB 3.0 host controller to send packets through the device tree. USB 3.0
hubs use this string to route packets to the correct port. This is fundamental
bus change from USB 2.0, where all packets were broadcast across the bus.

Devices (including hubs) under a root port receive the route string 0x0. Every
four bits in the route string represent a port on a hub. This length works
because USB 3.0 hubs are limited to 15 ports, and USB 2.0 hubs (with potentially
more ports) will never see packets with a route string. A port number of 0
means the packet is destined for that hub.

For example, a peripheral device might have a route string of 0x00097.
This means the device is connected to port 9 of the hub at depth 1.
The hub at depth 1 is connected to port 7 of a hub at depth 0.
The hub at depth 0 is connected to a root port.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff 9b8e7ba6 Wed May 27 19:10:44 MDT 2009 FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> USB: replace dma_sync_single and dma_sync_sg with dma_sync_single_for_cpu and dma_sync_sg_for_cpu

This replaces dma_sync_single() and dma_sync_sg() with
dma_sync_single_for_cpu() and dma_sync_sg_for_cpu() respectively
because they is an obsolete API; include/linux/dma-mapping.h says:

/* Backwards compat, remove in 2.7.x */
#define dma_sync_single dma_sync_single_for_cpu
#define dma_sync_sg dma_sync_sg_for_cpu

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff 9ac39f28 Wed Nov 12 14:19:49 MST 2008 Alan Stern <stern@rowland.harvard.edu> USB: add asynchronous autosuspend/autoresume support

This patch (as1160b) adds support routines for asynchronous autosuspend
and autoresume, with accompanying documentation updates. There
already are several potential users of this interface, and others are
likely to arise as autosuspend support becomes more widespread.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
/linux-master/include/linux/
H A Dusb.hdiff 130eac41 Tue Mar 28 07:10:43 MDT 2023 Arnd Bergmann <arnd@arndb.de> xhci: use pm_ptr() instead of #ifdef for CONFIG_PM conditionals

A recent patch caused an unused-function warning in builds with
CONFIG_PM disabled, after the function became marked 'static':

drivers/usb/host/xhci-pci.c:91:13: error: 'xhci_msix_sync_irqs' defined but not used [-Werror=unused-function]
91 | static void xhci_msix_sync_irqs(struct xhci_hcd *xhci)
| ^~~~~~~~~~~~~~~~~~~

This could be solved by adding another #ifdef, but as there is
a trend towards removing CONFIG_PM checks in favor of helper
macros, do the same conversion here and use pm_ptr() to get
either a function pointer or NULL but avoid the warning.

As the hidden functions reference some other symbols, make
sure those are visible at compile time, at the minimal cost of
a few extra bytes for 'struct usb_device'.

Fixes: 9abe15d55dcc ("xhci: Move xhci MSI sync function to to xhci-pci")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20230328131114.1296430-1-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 9c6d7788 Fri Aug 26 13:31:32 MDT 2022 Alan Stern <stern@rowland.harvard.edu> USB: core: Prevent nested device-reset calls

Automatic kernel fuzzing revealed a recursive locking violation in
usb-storage:

============================================
WARNING: possible recursive locking detected
5.18.0 #3 Not tainted
--------------------------------------------
kworker/1:3/1205 is trying to acquire lock:
ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at:
usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230

but task is already holding lock:
ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at:
usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230

...

stack backtrace:
CPU: 1 PID: 1205 Comm: kworker/1:3 Not tainted 5.18.0 #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.13.0-1ubuntu1.1 04/01/2014
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_deadlock_bug kernel/locking/lockdep.c:2988 [inline]
check_deadlock kernel/locking/lockdep.c:3031 [inline]
validate_chain kernel/locking/lockdep.c:3816 [inline]
__lock_acquire.cold+0x152/0x3ca kernel/locking/lockdep.c:5053
lock_acquire kernel/locking/lockdep.c:5665 [inline]
lock_acquire+0x1ab/0x520 kernel/locking/lockdep.c:5630
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x14f/0x1610 kernel/locking/mutex.c:747
usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230
usb_reset_device+0x37d/0x9a0 drivers/usb/core/hub.c:6109
r871xu_dev_remove+0x21a/0x270 drivers/staging/rtl8712/usb_intf.c:622
usb_unbind_interface+0x1bd/0x890 drivers/usb/core/driver.c:458
device_remove drivers/base/dd.c:545 [inline]
device_remove+0x11f/0x170 drivers/base/dd.c:537
__device_release_driver drivers/base/dd.c:1222 [inline]
device_release_driver_internal+0x1a7/0x2f0 drivers/base/dd.c:1248
usb_driver_release_interface+0x102/0x180 drivers/usb/core/driver.c:627
usb_forced_unbind_intf+0x4d/0xa0 drivers/usb/core/driver.c:1118
usb_reset_device+0x39b/0x9a0 drivers/usb/core/hub.c:6114

This turned out not to be an error in usb-storage but rather a nested
device reset attempt. That is, as the rtl8712 driver was being
unbound from a composite device in preparation for an unrelated USB
reset (that driver does not have pre_reset or post_reset callbacks),
its ->remove routine called usb_reset_device() -- thus nesting one
reset call within another.

Performing a reset as part of disconnect processing is a questionable
practice at best. However, the bug report points out that the USB
core does not have any protection against nested resets. Adding a
reset_in_progress flag and testing it will prevent such errors in the
future.

Link: https://lore.kernel.org/all/CAB7eexKUpvX-JNiLzhXBDWgfg2T9e9_0Tw4HQ6keN==voRbP0g@mail.gmail.com/
Cc: stable@vger.kernel.org
Reported-and-tested-by: Rondreis <linhaoguo86@gmail.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/YwkflDxvg0KWqyZK@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff e146caf3 Fri May 06 10:18:07 MDT 2022 Mathias Nyman <mathias.nyman@linux.intel.com> usb: Avoid extra usb SET_SEL requests when enabling link power management

The host needs to tell the device the exit latencies using the SET_SEL
request before device initiated link powermanagement can be enabled.

The exit latency values do not change after enumeration, it's enough
to set them once. So do like Windows 10 and issue the SET_SEL request
once just before setting the configuration.

This is also the sequence described in USB 3.2 specs "9.1.2 Bus
enumeration". SET_SEL is issued once before the Set Configuration
request, and won't be cleared by the Set Configuration,
Set Interface or ClearFeature (STALL) requests.

Only warm reset, hot reset, set Address 0 clears the exit latencies.
See USB 3.2 section 9.4.14 Table 9-10 Device parameters and events

Add udev->lpm_devinit_allow, and set it if SET_SEL was successful.
If not set, then don't try to enable device initiated LPM

We used to issue a SET_SEL request every time lpm is enabled for either
U1 or U2 link states, meaning a SET_SEL was issued twice after every
Set Configuration and Set Interface requests, easily accumulating to
over 15 SET_SEL requets during a USB3 webcam enumeration.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220506161807.3369439-1-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 2ddf7617 Wed Mar 16 09:55:13 MDT 2022 Vincent Mailhol <mailhol.vincent@wanadoo.fr> usb: remove third argument of usb_maxpacket()

Now that all users of usb_maxpacket() have been migrated to only use
two arguments, remove the third variadic argument which was introduced
for the transition.

Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20220317035514.6378-9-mailhol.vincent@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff ddd1198e Wed Sep 23 07:43:42 MDT 2020 Oliver Neukum <oneukum@suse.com> USB: correct API of usb_control_msg_send/recv

They need to specify how memory is to be allocated,
as control messages need to work in contexts that require GFP_NOIO.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
Link: https://lore.kernel.org/r/20200923134348.23862-9-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 9b6f0c4b Mon Mar 10 02:36:40 MDT 2014 Valentina Manea <valentina.manea.m@gmail.com> usbcore: rename struct dev_state to struct usb_dev_state

Since it is needed outside usbcore and exposed in include/linux/usb.h,
it conflicts with enum dev_state in rt2x00 wireless driver.

Mark it as usb specific to avoid conflicts in the future.

Signed-off-by: Valentina Manea <valentina.manea.m@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 9ef73dbd Wed Oct 09 09:01:40 MDT 2013 Hans de Goede <hdegoede@redhat.com> usb-anchor: Ensure poisened gets initialized to 0

And do so in a way which ensures that any fields added in the future will
also get properly zero-ed.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 9b790915 Fri May 17 01:08:51 MDT 2013 Julius Werner <jwerner@chromium.org> usb: ehci: Only sleep for post-resume handover if devices use persist

The current EHCI code sleeps a flat 110ms in the resume path if there
was a USB 1.1 device connected to its companion controller during
suspend, waiting for the device to reappear and reset so that it can be
handed back to the companion. This is necessary if the device uses
persist, so that the companion controller can actually see it during its
own resume path.

However, if the device doesn't use persist, this is entirely
unnecessary. We might just as well ignore it and have the normal device
detection/reset/handoff code handle it asynchronously when it eventually
shows up. As USB 1.1 devices are almost exclusively HIDs these days (for
which persist has no value), this can allow distros to shave another
tenth of a second off their resume time.

In order to enable this optimization, the patch also adds a new
usb_for_each_dev() iterator that is exported by the USB core and wraps
bus_for_each_dev() with the logic to differentiate between struct
usb_device and struct usb_interface on the usb_bus_type bus.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 9b790915 Fri May 17 01:08:51 MDT 2013 Julius Werner <jwerner@chromium.org> usb: ehci: Only sleep for post-resume handover if devices use persist

The current EHCI code sleeps a flat 110ms in the resume path if there
was a USB 1.1 device connected to its companion controller during
suspend, waiting for the device to reappear and reset so that it can be
handed back to the companion. This is necessary if the device uses
persist, so that the companion controller can actually see it during its
own resume path.

However, if the device doesn't use persist, this is entirely
unnecessary. We might just as well ignore it and have the normal device
detection/reset/handoff code handle it asynchronously when it eventually
shows up. As USB 1.1 devices are almost exclusively HIDs these days (for
which persist has no value), this can allow distros to shave another
tenth of a second off their resume time.

In order to enable this optimization, the patch also adds a new
usb_for_each_dev() iterator that is exported by the USB core and wraps
bus_for_each_dev() with the logic to differentiate between struct
usb_device and struct usb_interface on the usb_bus_type bus.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff 9e18c821 Fri Apr 02 11:22:09 MDT 2010 Alan Stern <stern@rowland.harvard.edu> USB: use PM core routines to enable/disable autosuspend

This patch (as1366) replaces the private routines
usb_enable_autosuspend() and usb_disable_autosuspend() with calls to
the standard pm_runtime_allow() and pm_runtime_forbid() functions in
the runtime PM framework. They do the same thing.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Completed in 326 milliseconds