Over two years ago, the Linux USB developers stated that they believed
there was no way to create a USB kernel driver that was not under the
GPL. This patch moves the USB apis to enforce that decision.
There are no known closed source USB drivers in the wild, so this patch
should cause no problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch exports two statistics to userspace:
/sys/bus/usb/device/.../power/connected_duration
/sys/bus/usb/device/.../power/active_duration
connected_duration is the total time (in msec) that the device has
been connected. active_duration is the total time the device has not
been suspended. With these two statistics, tools like PowerTOP can
calculate the percentage time that a device is active, i.e. not
suspended or auto-suspended.
Users can also use the active_duration to check if a device is actually
autosuspended. Currently, they can set power/level to auto and
power/autosuspend to a positive timeout, but there's no way to know from
userspace if a device was actually autosuspended without looking at the
dmesg output. These statistics will be useful in creating an automated
userspace script to test autosuspend for USB devices.
Signed-off-by: Sarah Sharp <sarah.a.sharp@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1023) updates the code in usb_reset_composite_device():
Some local variable declarations are moved to inner loops.
The interface locks are not acquired. This isn't necessary
any more; its only reason was to prevent an interface from
being suspended or resumed during the reset. But now
interface power management is controlled by the USB device
lock, not by the interface lock.
The check for whether the interface is registered is removed.
There doesn't seem to be any reason for checking; a driver
for a non-registered interface deserves to be informed of
device resets just as much as any other.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Distros (like SuSE) want to know this information, to make it easier
to handle support issues. Might as well let everyone benefit from this.
This is also enabled whenever CONFIG_USB_DEBUG is enabled, to help with
debugging.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch hands over the port to the companion when the
hub_port_connect_change fails.
Signed-off-by: Balaji Rao <balajirrao@gmail.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
this function will run in the context of the scsi error handler thread.
It must use GFP_NOIO instead of GFP_KERNEL to avoid a possible
deadlock.
Cc: stable <stable@kernel.org>
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1027) replaces a call to flush_scheduled_work() -- a
dangerous routine to invoke, especially while holding any sort of lock
-- with calls to cancel_work_sync() and cancel_delayed_work_sync().
This fixes Bugzilla #9532.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Introduce freezer-friendly wrappers around wait_event_interruptible() and
wait_event_interruptible_timeout(), originally defined in <linux/wait.h>, to
be used in freezable kernel threads. Make some of the freezable kernel
threads use them.
This is necessary for the freezer to stop sending signals to kernel threads,
which is implemented in the next patch.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix USB docbook warnings.
Warning(linux-2.6.23-git8//include/linux/usb/gadget.h:487): No description found for parameter 'g'
Warning(linux-2.6.23-git8//include/linux/usb/gadget.h:506): No description found for parameter 'g'
Warning(linux-2.6.23-git8//drivers/usb/core/hub.c:1416): No description found for parameter 'usb_dev'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch (as999) fixes a problem that sometimes shows up when host
controller driver modules are loaded in the wrong order. If ehci-hcd
happens to initialize an EHCI controller while the companion OHCI or
UHCI controller is in the middle of a port reset, the reset can fail
and the companion may get very confused. The patch adds an
rw-semaphore and uses it to keep EHCI initialization and port resets
mutually exclusive.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: David Brownell <david-b@pacbell.net>
Cc: David Miller <davem@davemloft.net>
Cc: Dely L Sy <dely.l.sy@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (jx001) fixes a variable assignment mistake in hub driver.
limited_power should be set to 0 if the hub is self-powered,and 1 if
the hub is bus-powered.
However, the effect of the code was exactly opposite to the spec's
statement for the Local Power Source field. The spec says, this field
is 1 meaning Local power supply lost while this field is 0 indicating
Local power supply good.(This statement is very confusing.)
So this patch switchs the 0 and 1.
Signed-off-by: Jason Xiao <jidong.xiao@gmail.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as989) makes usbcore flush all outstanding URBs for each
device as the device is suspended. This will be true even when
CONFIG_USB_SUSPEND is not enabled.
In addition, an extra can_submit flag is added to the usb_device
structure. That flag will be turned off whenever a suspend request
has been received for the device, even if the device isn't actually
suspended because CONFIG_USB_SUSPEND isn't set.
It's no longer necessary to check for the device state being equal to
USB_STATE_SUSPENDED during URB submission; that check can be replaced
by a check of the can_submit flag. This also permits us to remove
some questionable references to the deprecated power.power_state field.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as981) removes the remaining nontrivial usages of
urb->status from usbcore.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
As it is global, give it a usb specific name in the global namespace.
Cc: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
These USB API functions will do the full authorization/deauthorization
to be used for a device. When authorized we effectively allow a
configuration to be set. Reverse that when deauthorized.
Effectively this means that we have to clean all the configuration
descriptors on deauthorize and reload them when we authorized. We could
do without throwing them out for wired devices, but for wireless, we can
read them only after authenticating, and thus, when authorizing an
authenticated device we would need to read them. So to simplify, always
release them on deauthorize(), re-read them on authorize().
Also fix leak reported by Ragner Magalhaes; in usb_deauthorize_device(),
bNumConfigurations was being set to zero before the for loop, and thus
the different raw descriptors where never being freed.
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch takes hub.c:usb_new_device() and splits it in three parts:
- The actual actions of adding a new device (quirk detection,
announcement and autoresume tracking)
- Actual discovery and probing of the configuration and interfaces
(split into __usb_configure_device())
- Configuration of the On-the-go parameters (split into
__usb_configure_device_otg()).
The fundamental reasons for doing this split are clarity (smaller
functions are easier to maintain) and to allow part of the code to be
reused when authorizing devices to connect.
When a device is authorized connection, we need to run through the
hoops we didn't run when it was connected but not authorized, which is
basically parsing the configurations and probing
them. usb_configure_device() will do that for us.
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as947) changes the device initialization and enumeration
code in hub.c; now udev->devnum will be set to 0 while the device is
being accessed at address 0. Until now this wasn't needed because the
address value was passed as part of urb->pipe; without that field the
device address must be stored elsewhere.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as944) adds an explicit "enabled" field to the
usb_host_endpoint structure and uses it in place of the current
mechanism. This is merely a time-space tradeoff; it makes checking
whether URBs may be submitted to an endpoint simpler. The existing
mechanism is efficient when converting urb->pipe to an endpoint
pointer, but it's not so efficient when urb->ep is used instead.
As a side effect, the procedure for enabling an endpoint is now a
little more complicated. The ad-hoc inline code in usb.c and hub.c
for enabling ep0 is now replaced with calls to usb_enable_endpoint,
which is no longer static.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Some devices have a bug which causes them to send a 1-byte reply to
Get-Device-Status requests instead of 2 bytes as required by the
spec. This doesn't play well with autosuspend, since we look for a
valid status reply to make sure the device is still present when it
resumes. Without both bytes, we assume the device has been
disconnected.
Lack of the second byte shouldn't matter much, since the spec requires
it always to be equal to 0. Hence this patch (as959) causes
finish_port_resume() to accept a 1-byte reply as valid.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as937) fixes a minor bug in the autosuspend usage-counting
code. Each hub's usage counter keeps track of the number of
unsuspended children. However the current driver increments the
counter after registering a new child, by which time the child may
already have been suspended and caused the counter to go negative.
The obvious solution is to increment the counter before registering
the child.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Currently, the freezer treats all tasks as freezable, except for the kernel
threads that explicitly set the PF_NOFREEZE flag for themselves. This
approach is problematic, since it requires every kernel thread to either
set PF_NOFREEZE explicitly, or call try_to_freeze(), even if it doesn't
care for the freezing of tasks at all.
It seems better to only require the kernel threads that want to or need to
be frozen to use some freezer-related code and to remove any
freezer-related code from the other (nonfreezable) kernel threads, which is
done in this patch.
The patch causes all kernel threads to be nonfreezable by default (ie. to
have PF_NOFREEZE set by default) and introduces the set_freezable()
function that should be called by the freezable kernel threads in order to
unset PF_NOFREEZE. It also makes all of the currently freezable kernel
threads call set_freezable(), so it shouldn't cause any (intentional)
change of behaviour to appear. Additionally, it updates documentation to
describe the freezing of tasks more accurately.
[akpm@linux-foundation.org: build fixes]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Nigel Cunningham <nigel@nigel.suspend2.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch (as920) adds an extra level of protection to the
USB-Persist facility. Now it will apply by default only to hubs; for
all other devices the user must enable it explicitly by setting the
power/persist device attribute.
The disconnect_all_children() routine in hub.c has been removed and
its code placed inline. This is the way it was originally as part of
hub_pre_reset(); the revised usage in hub_reset_resume() is
sufficiently different that the code can no longer be shared.
Likewise, mark_children_for_reset() is now inline as part of
hub_reset_resume(). The end result looks much cleaner than before.
The sysfs interface is updated to add the new attribute file, and
there are corresponding documentation updates.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as919) unifies the code paths used for normal resume and
for reset-resume. Earlier I had failed to note a section in the USB
spec which requires the host to resume a suspended port before
resetting it if the attached device is enabled for remote wakeup.
Since the port has to be resumed anyway, we might as well reuse the
existing code.
The main changes are:
usb_reset_suspended_device() is eliminated.
usb_root_hub_lost_power() is moved down next to the
hub_reset_resume() routine, to which it is logically
related.
finish_port_resume() does a port reset() if the device's
reset_resume flag is set.
usb_port_resume() doesn't check whether the port is initially
enabled if this is a USB-Persist sort of resume.
Code to perform the port reset is added to the resume pathway
for the non-CONFIG_USB_SUSPEND case.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as918) introduces a new USB driver method: reset_resume.
It is called when a device needs to be reset as part of a resume
procedure (whether because of a device quirk or because of the
USB-Persist facility), thereby taking over a role formerly assigned to
the post_reset method. As a consequence, post_reset no longer needs
an argument indicating whether it is being called as part of a
reset-resume. This separation of functions makes the code clearer.
In addition, the pre_reset and post_reset method return types are
changed; they now must return an error code. The return value is
unused at present, but at some later time we may unbind drivers and
re-probe if they encounter an error during reset handling.
The existing pre_reset and post_reset methods in the usbhid,
usb-storage, and hub drivers are updated to match the new
requirements. For usbhid the post_reset routine is also used for
reset_resume (duplicate method pointers); for the other drivers a new
reset_resume routine is added. The change to hub.c looks bigger than
it really is, because mark_children_for_reset_resume() gets moved down
next to the new hub_reset_resume() routine.
A minor change to usb-storage makes the usb_stor_report_bus_reset()
routine acquire the host lock instead of requiring the caller to hold
it already.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
CC: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as917) removes a now-unnecessary level of subroutine
nesting from hub.c. Since usb_port_suspend() does nothing but call
hub_port_suspend(), and usb_port_resume() does nothing but call
hub_port_resume(), there's no reason to keep the routines separate.
Also included in the patch are a few cosmetic changes involving
whitespace and use of braces.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as916) completes the separation of code paths for suspend
and resume of root hubs as opposed to non-root devices. Root hubs
will be power-managed through their bus_suspend and bus_resume
methods, whereas normal devices will use usb_port_suspend() and
usb_port_resume().
Changes to the hcd_bus_{suspend,resume} routines mostly represent
motion of code that was already present elsewhere. They include:
Adding debugging log messages,
Setting the device state appropriately, and
Adding a resume recovery time delay.
Changes to the port-suspend and port-resume routines in hub.c include:
Removal of checks for root devices (since they will never
be triggered), and
Removal of checks for NULL or invalid device pointers (these
were left over from earlier kernel versions and aren't needed
at all).
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as915b) combines the public routine usb_port_suspend() and
the private routine __usb_port_suspend() into a single function.
By removing the explicit mention of otg_port in the call to
__usb_port_suspend(), we prevent a possible error in which the system
tries to perform HNP on the wrong port when a non-targeted device is
plugged into a non-OTG port.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Patch is to prevent the OTG host of doing 3 times enumeration of
device when the Host suspends for HNP. The error code used in
this case is ENOTSUPP.
Signed-off-by: Vikram Pandita <vikram.pandita@ti.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Okay, found it. The root cause here was a missing CONFIG_USB_SUSPEND=y,
which means the hci_usb device never got marked as USB_STATE_SUSPENDED,
which then caused the loop to go on forever.
The system works fine now with CONFIG_USB_SUSPEND=y in the .config.
Here's the patch to prevent future lockups for this or other causes.
I no longer need it, but it does still seem a good idea.
Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as898) changes the port reset code in the hub driver. If
a connect change occurs, it is reported the same way as a disconnect
(which of course is what it really is).
It also changes usb_reset_device(), to prevent the routine from futilely
retrying the reset after a disconnect has occurred.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as888) adds a new USB device quirk for devices which are
unable to resume correctly. By using the new code added for the
USB-persist facility, it is a simple matter to reset these devices
instead of resuming them. To get things kicked off, a quirk entry is
added for the Philips PSC805.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as886) adds the controversial USB-persist facility,
allowing USB devices to persist across a power loss during system
suspend.
The facility is controlled by a new Kconfig option (with appropriate
warnings about the potential dangers); when the option is off the
behavior will remain the same as it is now. But when the option is
on, people will be able to use suspend-to-disk and keep their USB
filesystems intact -- something particularly valuable for small
machines where the root filesystem is on a USB device!
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This revised patch (as893c) improves the method used by the hub driver
to release its private data structure. The current code is non-robust,
relying on a memory region not getting reused by another driver after
it has been freed. The patch adds a reference count to the structure,
resolving the question of when to release it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as892) removes the "locktree" routine from the hub driver.
It currently is used in only one place, by a single kernel thread;
hence it isn't doing any good.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as889) prevents the hub driver from trying to resume a
port when there is a new connection. For one thing, the resume is not
needed -- the upcoming port reset will clear the suspend feature
automatically. For another, on some systems the resume fails and
causes problems.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as885) moves the root-hub bus_suspend() and bus_resume()
method calls from the hub driver's suspend and resume methods into the
usb_generic driver methods, where they make just as much sense.
Their old locations were not fully correct. For example, in a kernel
compiled without CONFIG_USB_SUSPEND, if one were to do:
echo -n 1-0:1.0 >/sys/bus/usb/drivers/hub/unbind
to unbind the hub driver from a root hub, there would then be no way
to suspend that root hub. Attempts to put the system to sleep would
fail; the USB controller driver would refuse to suspend because the
root hub was still active.
The patch also makes a very slight change in the way devices with no
driver are handled during suspend. Rather than doing a standard USB
port-suspend directly, now the suspend routine in usb_generic is
called. In practice this should never affect anyone.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The prev_state member of struct dev_pm_info (defined in include/linux/pm.h) is
only used during a resume to check if the device's state before the suspend was
'off', in which case the device is not resumed. However, in such cases the
decision whether or not to resume the device should be made on the driver level
and the resume callbacks from the device's bus and class should be executed
anyway (the may be needed for some things other than just powering on the
device).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as912) replaces a couple of calls to flush_workqueue()
with cancel_sync_work() and cancel_rearming_delayed_work(). Using a
more directed approach allows us to avoid some nasty deadlocks. The
prime example occurs when a first-level device (the parent is a root
hub) is removed while at the same time the root hub gets a remote
wakeup request. khubd would try to flush the autosuspend workqueue
while holding the root-hub's lock, and the remote-wakeup workqueue
routine would be waiting to lock the root hub.
The patch also reorganizes the power management portion of
usb_disconnect(), separating it out into its own routine. The
autosuspend workqueue entry is cancelled immediately instead of
waiting for the device's release routine. In addition,
synchronization with the autosuspend thread is carried out even for
root hubs (an oversight in the original code).
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg KH <gregkh@suse.de>
Cc: Mark Lord <lkml@rtr.ca>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch (as910) fixes a ratelimit modification so that the
original error-handling path will be followed even when the log-rate
limitation kicks in.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as905) removes a micro-optimization from the hub port
initialization code. Previously we had been using a short timeout on
the first attempt the read the device descriptor; now we will use the
standard timeout length.
It's not clear that the short timeout ever provided any benefit. And
now we know of one case where it actually hurts: The device can't meet
the short timeout and then it gets terminally confused.
This fixes Bugzilla #8444.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.
Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch (as877) adds a "last_busy" field to struct usb_device, for
use by the autosuspend framework. Now if an autosuspend call comes at
a time when the device isn't busy but hasn't yet been idle for long
enough, the timer can be set to exactly the desired value. And we
will be ready to handle things like HID drivers, which can't maintain
a useful usage count and must rely on the time-of-last-use to decide
when to autosuspend.
The patch also makes some related minor improvements:
Move the calls to the autosuspend condition-checking routine
into usb_suspend_both(), which is the only place where it
really matters.
If the autosuspend timer is already running, don't stop
and restart it.
Replace immediate returns with gotos so that the optional
debugging ouput won't be bypassed.
If autoresume is disabled but the device is already awake,
don't return an error for an autoresume call.
Don't try to autoresume a device if it isn't suspended.
(Yes, this undercuts the previous change -- so sue me.)
Don't duplicate existing code in the autosuspend work routine.
Fix the kerneldoc in usb_autopm_put_interface(): If an
autoresume call fails, the usage counter is left unchanged.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
o The "real" usb-devices export now a device node which can
populate /dev/bus/usb.
o The usb_device class is optional now and can be disabled in the
kernel config. Major/minor of the "real" devices and class devices
are the same.
o The environment of the usb-device event contains DEVNUM and BUSNUM to
help udev and get rid of the ugly udev rule we need for the class
devices.
o The usb-devices and usb-interfaces share the same bus, so I used
the new "struct device_type" to let these devices identify
themselves. This also removes the current logic of using a magic
platform-pointer.
The name of the device_type is also added to the environment
which makes it easier to distinguish the different kinds of devices
on the same subsystem.
It looks like this:
add@/devices/pci0000:00/0000:00:1d.1/usb2/2-1
ACTION=add
DEVPATH=/devices/pci0000:00/0000:00:1d.1/usb2/2-1
SUBSYSTEM=usb
SEQNUM=1533
MAJOR=189
MINOR=131
DEVTYPE=usb_device
PRODUCT=46d/c03e/2000
TYPE=0/0/0
BUSNUM=002
DEVNUM=004
This udev rule works as a replacement for usb_device class devices:
SUBSYSTEM=="usb", ACTION=="add", ENV{DEVTYPE}=="usb_device", \
NAME="bus/usb/$env{BUSNUM}/$env{DEVNUM}", MODE="0644"
Updated patch, which needs the device_type patches in Greg's tree.
I also got a bugzilla assigned for this. :)
https://bugzilla.novell.com/show_bug.cgi?id=250659
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as866) adds new entry points for external USB device
suspend and resume requests, as opposed to internally-generated
autosuspend or autoresume. It also changes the existing
remote-wakeup code paths to use the new routines, since remote wakeup
is not the same as autoresume.
As part of the change, it turns out to be necessary to do remote
wakeup of root hubs from a workqueue. We had been using khubd, but it
does autoresume rather than an external resume. Using the
ksuspend_usb_wq workqueue for this purpose seemed a logical choice.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Duplicate what Zach Brown did for pr_debug in commit
8b2a1fd1b3
[akpm@linux-foundation.org: fix a couple of things which broke]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
flaky hardware can cause a lot of debounce failed messages. To limit
the performance impact, a ratelimit should be used.
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This adds a blacklist to the USB core to handle some autosuspend and
string issues that devices have.
Originally written by Oliver, but hacked up a lot by Greg.
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as849) fixes a bug in the USB hub driver. A single
pre-allocated buffer is used for all port status reads, but nothing
guarantees exclusive use of the buffer. A mutex is added to provide
this guarantee.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as847) makes some small changes to the hub driver's
suspend method:
For root hubs, the status URB should be unlinked and other
activity stopped _before_ the bus_suspend method is called.
The test for hdev->bus being NULL has been removed, since
it can never succeed.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The whole approach is simply wrong. Forking a thread means that
- errors are ignored
- locking is ignored
Doing this correctly would require major surgery for questionable benefit.
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Disable the USB_MULTITHREAD_PROBE option because it causes crashes on
people's machines and they never remember to actually read the config
help files.
No one likes this, everyone hates it, I'm going to go eat worms...
The full logic will be ripped out later.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Move process freezing functions from include/linux/sched.h to freezer.h, so
that modifications to the freezer or the kernel configuration don't require
recompiling just about everything.
[akpm@osdl.org: fix ueagle driver]
Signed-off-by: Nigel Cunningham <nigel@suspend2.net>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
SLAB_KERNEL is an alias of GFP_KERNEL.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
SLAB_ATOMIC is an alias of GFP_ATOMIC
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix up arch-specific work items where possible to use the new work_struct and
delayed_work structs.
Three places that enqueue bits of their stack and then return have been marked
with #error as this is not permitted.
Signed-Off-By: David Howells <dhowells@redhat.com>
Conflicts:
drivers/infiniband/core/iwcm.c
drivers/net/chelsio/cxgb2.c
drivers/net/wireless/bcm43xx/bcm43xx_main.c
drivers/net/wireless/prism54/islpci_eth.c
drivers/usb/core/hub.h
drivers/usb/input/hid-core.c
net/core/netpoll.c
Fix up merge failures with Linus's head and fix new compilation failures.
Signed-Off-By: David Howells <dhowells@redhat.com>
Thanks to several earlier patches, usb_autosuspend_device() and
usb_autoresume_device() are never called with a second argument other
than 1. This patch (as819) removes the now-redundant argument.
It also consolidates some common code between those two routines,
putting it into a new subroutine called usb_autopm_do_device(). And
it includes a sizable kerneldoc update for the affected functions.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as818b) simplifies autosuspend processing by keeping track
of the number of unsuspended children of each USB hub. This will
permit us to avoid a good deal of unnecessary work all the time; we
will no longer have to create a bunch of workqueue entries to carry
out autosuspend requests, only to have them fail because one of the
hub's children isn't suspended.
The basic idea is simple. There already is a usage counter in the
usb_device structure for preventing autosuspends. The patch just
increments that counter for every unsuspended child. There's only one
tricky part: When a device disconnects we need to remember whether it
was suspended at the time (leave the counter alone) or not (decrement
the counter).
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as817) simplifies the remote-wakeup processing in the hub
driver. Now instead of using a specialized code path, it relies on
the standard USB resume routines. The hub_port_resume() function does
an initial get_port_status() to see whether the port has already
resumed itself (as it does when a remote-wakeup request is sent).
This will slow down handling of other resume events slightly, but not
enough to matter.
The patch also changes the hub_port_status() routine, making it return
an error if a short reply is received.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as742b) adds autosuspend/autoresume support to the USB hub
driver. The largest aspect of the change is that we no longer need a
special flag for root hubs that want to be resumed. Now every hub is
autoresumed whenever khubd needs to access it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Might speed up some systems. If nothing else, a bad driver should not
take the whole USB subsystem down with it.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as809b) moves the declaration of the hub driver's private
data structure from hub.h into the hub.c source file. Lots of other
files import hub.h; they have no need to know about the details of the
hub driver's private data.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Wireless USB Host Controllers accept a large number of devices per
host, which shows up as a large number of ports in its root hub.
When the number of ports in a hub device goes over 16, the activation
of the hub fails with the cryptic message in klogd.
hub 2-0:1.0: activate --> -22
Following this further, it was seen that:
hub_probe()
hub_configure()
generates pipe number
pseudo allocates buffer 'maxp' bytes in size using usb_maxpacket()
The endpoint descriptor for a root hub interrupt endpoint is
declared in
drivers/usb/core/hcd.c:hs_rh_config_descriptor and declares it
to be size two (supporting 15 devices max).
hub_activate()
usb_hcd_submit_urb()
rh_urb_enqueue()
urb->pipe is neither int nor ctl, so it errors out
rh_queue_status()
Returns -EINVAL because the buffer length is smaller
than the minimum needed to report all the hub port
bits as in accordance with USB2.0[11.12.3]. There has
to be trunc((PORTS + 1 + 7) / 8) bytes of space at
least.
Alan Stern confirmed that the reason for reading maxpktsize and not
the right amount is because some hubs are known to return more data
and thus cause overflow.
So this patch simply changes the code to make the interrupt endpoint's
max packet size be at least the minimum required by USB_MAXCHILDREN
(instead of a fixed magic number) and add documentation for that. This
way we are always ahead of the limit.
Signed-off-by: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Remove complaint from newer GCCs; they don't like forward function
declarations except in top-level contexts.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
This patch (as791b) fixes things up to avoid compiler warnings or
errors when CONFIG_USB_SUSPEND or CONFIG_PM isn't set.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Somewhere along the line, a variable in a USB-OTG codepath
stopped being used; this removes the relevant compiler warning.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch(as785) forces the PM core to resume a root hub after a
power loss during system sleep. If the root hub had been suspended
before the system sleep then normally the PM core would not resume it
afterward. Without this resume, various sorts of wakeup events (like
port change events) can get lost.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The patch removes unneeded casts for the following (void *) pointers:
- struct file: private
- struct urb: context
- struct usb_bus: hcpriv
- return value of kmalloc()
The patch also contains some whitespace cleanup in the relevant areas.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as740) removes the existing support for autosuspend of
root hubs. That support fit in rather awkwardly with the rest of
usbcore and it was used only by ohci-hcd. It won't be needed any more
since the hub driver will take care of autosuspending all hubs, root
or external.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as739) adds the basic infrastructure for USB autosuspend
and autoresume. The main features are:
PM usage counters added to struct usb_device and struct
usb_interface, indicating whether it's okay to autosuspend
them or they are currently in use.
Flag added to usb_device indicating whether the current
suspend/resume operation originated from outside or as an
autosuspend/autoresume.
Flag added to usb_driver indicating whether the driver
supports autosuspend. If not, no device bound to the driver
will be autosuspended.
Mutex added to usb_device for protecting PM operations.
Unlike the device semaphore, the locking rule for the pm_mutex
is that you must acquire the locks going _up_ the device tree.
New routines handling autosuspend/autoresume requests for
interfaces and devices.
Suspend and resume requests are propagated up the device tree
(but not outside the USB subsystem).
work_struct added to usb_device, for carrying out delayed
autosuspend requests.
Autoresume added (and autosuspend prevented) during probe and
disconnect.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as778) adds a field to struct usb_device to store the
device's level in the USB tree. In itself this number isn't really
important. But the overhead is very low, and in a later patch it will
be used for preventing bogus warnings from the lockdep checker.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
New code being pushed to linuxuwb.org requires this patch to connect
WUSB devices.
Signed-off-by: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch teaches the USB stack handling of WUSB devices (those whose
speed is USB_SPEED_VARIABLE). For these devices, we need to set ep0's
maxpacketsize to 512 (even though the device descriptor reports it as
0xff).
New code being pushed to linuxuwb.org requires this patch to connect WUSB
devices.
Signed-off-by: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch enables the USB stack to recognize WUSB devices (from a
WUSB HCD) and assigns them the proper speed setting
(USB_SPEED_VARIABLE).
1. Introduce usb_hcd->wireless to mark a host controller instance as
being wireless, and thus having wireless 'fake' ports.
[discarded previous model of using a reserved bit in the port_stat
struct to do this; thanks to Alan Stern for indicating the
proper way to do it].
2. Introduce hub.c:hub_is_wusb() that tests if a hub is a WUSB root
hub (WUSB doesn't have non-root hubs).
New code being pushed to linuxuwb.org requires this patch to connect WUSB
devices.
Signed-off-by: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We don't want khubd to start interfering in the device-resume process
merely because the PORT_STATUS_C_SUSPEND feature happens to be set.
Ports need to be marked as busy while a resume is taking place.
In addition, so long as ports are marked as busy, khubd won't be able to
clear their various status-change features. On an interrupt-driven root
hub this could lead to an interrupt storm. Root hub IRQs should not be
re-enabled until the busy_bits value is equal to 0.
This patch (as765) fixes these two potential problems.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as736) makes the hub driver more readable by improving the
usage of "#ifdef CONFIG_PM" and "#ifdef CONFIG_USB_SUSPEND".
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as734) rationalizes the various tests of device state and
power states. There are duplications and mistaken tests in several
places.
Perhaps the most interesting challenge is where the hub driver tests to
see that all the child devices are suspended before allowing itself to
be suspended. When CONFIG_USB_SUSPEND is set the test is
straightforward, since we expect that the children _will_ be suspended.
But when CONFIG_USB_SUSPEND isn't set, it's not so clear what should be
done. The code compromises by checking the child's
power.power_state.event field.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as733) fixes up the places where device states and power
states are set in usbcore. Right now things are duplicated or missing;
this should straighten things out.
The idea is that udev->state is USB_STATE_SUSPENDED exactly when the
device's upstream port has been suspended, whereas
udev->dev.power.power_state.event reflects the result of the last call
to the suspend/resume routines (which might not actually change the
device state, especially if CONFIG_USB_SUSPEND isn't set).
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as717b) removes the existing recursion in hub resume code:
Resuming a hub will no longer automatically resume the devices attached
to the hub.
At the same time, it adds one level of recursion: Suspending a USB
device will automatically suspend all the device's interfaces. Failure
at an intermediate stage will cause all the already-suspended interfaces
to be resumed. Attempts to suspend or resume an interface by itself will
do nothing, although they won't return an error. Thus the regular
system-suspend and system-resume procedures should continue to work as
before; only runtime PM will be affected.
The patch also removes the code that tests state of the interfaces
before suspending a device. It's no longer needed, since everything
gets suspended together.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as714b) makes usb_generic into a usb_device_driver capable
of being probed and unbound, just like other drivers. A fair amount of
the work that used to get done during discovery or removal of a USB
device have been moved to the probe and disconnect methods of
usb_generic: creating the sysfs attributes and selecting an initial
configuration. However the normal behavior should continue to be the
same as before.
We will now have the possibility of creating other USB device drivers,
They will assist with exporting devices to remote systems
(USB-over-TCPIP) or to paravirtual guest operating systems.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This revised patch (as715b) renames usb_suspend_device to
usb_port_suspend, usb_resume_device to usb_port_resume, and
finish_device_resume to finish_port_resume. There was no objection to
the original version of the patch so this should be okay to apply.
The revision was needed only because I have re-arranged the order of the
earlier patches.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as731) makes a couple of small fixes to the hub_port_resume
routine:
Don't return status >= 0 when an error occurs;
Clear the port-change-suspend status indicator after
resuming a device.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
finish_device_resume() in the hub driver isn't careful always to return
a negative code in all the error pathways. It also doesn't return 0 in
all the success pathways. This patch (as724) fixes the behavior.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as700) modifies the hub driver to take advantage of the new
usb_reset_composite_device API. The existing code had special-case
calls stuck into usb_reset_device, just before and after the reset.
With the new version there's no need for special-case stuff; it all
happens naturally in the form of pre_reset and post_reset notifications.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as699) adds usb_reset_composite_device(), a routine for
sending a USB port reset to a device with multiple interfaces owned by
different drivers. Drivers are notified about impending and completed
resets through two new methods in the usb_driver structure.
The patch modifieds the usbfs ioctl code to make it use the new routine
instead of usb_reset_device(). Follow-up patches will modify the hub,
usb-storage, and usbhid drivers so they can utilize this new API.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
RNDIS devices don't get configured owing to a typo in
choose_configuration(). This patch from Giridhar Pemmasani fixes the
typo.
From: Giridhar Pemmasani <giri@lmc.cs.sunysb.edu>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2.6.16 introduces USB power budgeting in the Linux kernel, and since then, a
fair number of users have observed that some of their devices no longer work in
unpowered hubs (this is not a bug, the devices claim that they need more than
100mA).
The very least we can do is print an informational message to the kernel log
when this happens, otherwise it is not at all clear why the device was not
accepted.
Signed-off-by: Daniel Drake <dsd@gentoo.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Some hubs claim not to support port-power switching, and right now the
hub driver believes them and does not enable power to their ports.
However it turns out that even though they don't actually switch power,
they do ignore all events on a port until told to turn on the power!
This problem has been reported by several users.
This revised patch (as672b) makes the hub driver always try to turn on
port power to all hubs, regardless of what the hub descriptor says. It
also adds a comment explaining the need for this.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The choose_configuration() routine contains code the determine the
device's power source, so that configurations requiring external power
can be ruled out if the device is running on bus power. Unfortunately
it turns out that some devices have errors in their config descriptors
and other devices don't like the GET_DEVICE_STATUS request.
Since that information wasn't used for anything else, this patch (as673)
removes the code, leaving only a comment. It fixes bugzilla entry
#6448.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
USB OTG devices are not required to support external hubs. This adds a
configuration option to disable that support.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
In a couple of places, usbcore assumes that a USB device configuration
will have a nonzero number of interfaces. Having no interfaces may or
may not be allowed by the USB spec; in any event we shouldn't die if we
encounter such a thing. This patch (as662) removes the assumptions.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as647) fixes a small error introduced by a recent change to
the USB core suspend/resume code.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This makes usbcore use the driver model wakeup flags for host controllers
and for their root hubs. Since previous patches have removed all users of
the HCD flags they replace, this converts the last users of those flags.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
the patch below converts a bunch of semaphores-used-as-mutex in the USB
code to mutexes
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as614) makes a small change to the part of the hub driver
responsible for remote wakeup of root hubs. When these wakeups occur
the driver is suspended, and in case the resume fails the driver should
remain suspended -- it shouldn't try to proceed with its normal
processing.
This will hardly ever matter in normal use, but it did crop up while I
was debugging a different problem.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as610) adds a field to struct usb_device to store the device's
port number. This allows us to remove several loops in the hub driver
(searching for a particular device among all the entries in the parent's
array of children).
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as609) changes the way we keep track of power budgeting for
USB hubs and devices, and it updates the choose_configuration routine to
take this information into account. (This is something we should have
been doing all along.) A new field in struct usb_device holds the amount
of bus current available from the upstream port, and the usb_hub structure
keeps track of the current available for each downstream port.
Two new rules for configuration selection are added:
Don't select a self-powered configuration when only bus power
is available.
Don't select a configuration requiring more bus power than is
available.
However the first rule is #if-ed out, because I found that the internal
hub in my HP USB keyboard claims that its only configuration is
self-powered. The rule would prevent the configuration from being chosen,
leaving the hub & keyboard unconfigured. Since similar descriptor errors
may turn out to be fairly common, it seemed wise not to include a rule
that would break automatic configuration unnecessarily for such devices.
The second rule may also trigger unnecessarily, although this should be
less common. More likely it will annoy people by sometimes failing to
accept configurations that should never have been chosen in the first
place.
The patch also changes usbcore's reaction when no configuration is
suitable. Instead of raising an error and rejecting the device, now
the core will simply leave the device unconfigured. People can always
work around such problems by installing configurations manually through
sysfs.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The earlier USB locking updates didn't touch the suspend/resume
routines. They need updating as well, since now the caller holds the
device semaphore. This patch (as608) makes the necessary changes. It
also adds a line to store the correct power state when a device is
resumed, something which was unaccountably missing.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as606b) is an updated version of my earlier patch to
disconnect children from a hub device when the hub driver is unbound.
Thanks to the changes in the driver core locking, we now know that the
entire hub device (and not just the interface) is locked whenever the
hub driver's disconnect method runs. Hence it is safe to disconnect the
child device structures immediately instead of deferring the job.
The earlier version of the patch neglected to disable the hub's ports.
We don't want to forget that; otherwise we'd end up with live devices
using addresses that have been recycled. This update adds the necessary
code.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as605) removes the private udev->serialize semaphore,
relying instead on the locking provided by the embedded struct device's
semaphore. The changes are confined to the core, except that the
usb_trylock_device routine now uses the return convention of
down_trylock rather than down_read_trylock (they return opposite values
for no good reason).
A couple of other associated changes are included as well:
Now that we aren't concerned about HCDs that avoid using the
hcd glue layer, usb_disconnect no longer needs to acquire the
usb_bus_lock -- that can be done by usb_remove_hcd where it
belongs.
Devices aren't locked over the same scope of code in
usb_new_device and hub_port_connect_change as they used to be.
This shouldn't cause any trouble.
Along with the preceding driver core patch, this needs a lot of testing.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as515b) adds a routine to usbcore to simplify handling of
host controllers that lost power or were reset during suspend/resume.
The new core routine marks all the child devices of the root hub as
NOTATTACHED and tells khubd to disconnect the device structures as soon
as possible.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This fixes some bugs in EHCI suspend/resume that joined us over the past
few releases (as usbcore, PCI, pmcore, and other components evolved):
- Removes suspend and resume recursion from the EHCI driver, getting
rid of the USB_SUSPEND special casing.
- Updates the wakeup mechanism to work again; there's a newish usbcore
call it needs to use.
- Provide simpler tests for "do we need to restart from scratch", to
address another case where PCI Vaux was lost. (In this case it was
restoring a swsusp snapshot, but there could be others.)
Un-exports a symbol that was temporarily exported.
A notable change from previous version is that this doesn't move
the spinlock init, so there's still a resume/reinit path bug.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This lets us remove a lot of code in the drivers that were all checking
the same thing. It also found some bugs in a few of the drivers, which
has been fixed up.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With CONFIG_PM=n:
drivers/built-in.o(.text+0x1098c): In function `hub_thread':
drivers/usb/core/hub.c:2673: undefined reference to `.dpm_runtime_resume'
drivers/built-in.o(.text+0x10998):drivers/usb/core/hub.c:2674: undefined reference to `.dpm_runtime_resume'
Please, never ever ever put extern decls into .c files. Use the darn header
files :(
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as592) makes a few small improvements to the way device
strings are handled, and it fixes some bugs in a couple of other sysfs
attribute routines. (Look at show_configuration_string() to see what I
mean.)
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as590) fixes up all the remaining places where usbcore can
use kzalloc rather than kmalloc/memset.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This should let us get rid of all of the different hooks in the USB core for
when something has changed.
Also, some other parts of the kernel have wanted to know this kind of
information at times.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as580) is perhaps the only result from the long discussion I
had with David about his changes to the root-hub suspend/resume code. It
renames the hub_suspend and hub_resume methods in struct usb_hcd to
bus_suspend and bus_resume. These are more descriptive names, since the
methods really do suspend or resume an entire USB bus, and less likely to
be confused with the hub_suspend and hub_resume routines in hub.c.
It also takes David's advice about removing the layer of bus glue, where
those methods are called. And it implements a related change that David
made to the other HCDs but forgot to put into dummy_hcd.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Also has the nice benefit of making sparc alignment issues go away.
Thanks to David Miller for pointing out the problems here.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/usb/core/hub.c | 22 ++++++++++++----------
drivers/usb/core/hub.h | 2 +-
2 files changed, 13 insertions(+), 11 deletions(-)
The way we're looking at USB suspend lately doesn't expect drivers to
call usb_suspend_device() or usb_resume_device() directly; that'll
be implicit when no interfaces are in use.
This patch removes those APIs from visibility outside usbcore.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
drivers/usb/core/hub.c | 12 ++++--------
drivers/usb/core/usb.h | 4 ++++
include/linux/usb.h | 5 -----
3 files changed, 8 insertions(+), 13 deletions(-)
This patch associates hub suspend and resume logic (including for root hubs)
with CONFIG_PM -- instead of CONFIG_USB_SUSPEND as before -- thereby unifying
two troublesome versions of suspend logic into just one. It'll be easier to
keep things right from now on.
- Now usbcore _always_ calls hcd->hub_suspend as needed, instead of
only when USB_SUSPEND is enabled:
* Those root hub methods are now called from hub suspend/resume;
no more skipping between layers during device suspend/resume;
* It now handles cases allowed by sysfs or autosuspended root hubs,
by forcing the hub interface to resume too.
- All devices, including virtual root hubs, now get the same treatment
on their resume paths ... including re-activating all their interfaces.
Plus it gets rid of those stub copies of usb_{suspend,resume}_device(), and
updates the Kconfig to match the new definition of USB_SUSPEND: it provides
(a) selective suspend, downstream from hubs; and (b) remote wakeup, upstream
from any device configuration which supports it.
This calls for minor followup patches for most HCDs (and their PCI glue).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/usb/core/Kconfig | 11 ++-
drivers/usb/core/hub.c | 163 +++++++++++++++++++++++++----------------------
2 files changed, 97 insertions(+), 77 deletions(-)
This patch collects various small updates related to root hubs, to shrink
later patches which build on them.
- For root hub suspend/resume support:
* Make the existing usb_hcd_resume_root_hub() routine respect pmcore
locking, exporting and using the dpm_runtime_resume() method.
* Add a new usb_hcd_suspend_root_hub() to pair with that routine.
(Essential to make OHCI autosuspend behave again...)
* HC_SUSPENDED by itself only refers to the root hub's downstream ports.
So let HCDs see root hub URBs unless the parent device is suspended.
- Remove an assertion we no longer need (and now, also don't want).
- Generic suspend/resume updates to work better with swsusp.
* Ignore the FREEZE vs SUSPEND distinction for hardware; trying to
use it breaks the swsusp snapshots it's supposed to help (sigh).
* On resume, mark devices as resumed right away, but then
do nothing else if the device is marked NOTATTACHED.
These changes shouldn't be very noticable by themselves.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/base/power/runtime.c | 1
drivers/usb/core/hcd.c | 64 ++++++++++++++++++++++++++++++++++++++-----
drivers/usb/core/hcd.h | 1
drivers/usb/core/hub.c | 45 ++++++++++++++++++++++++------
drivers/usb/core/usb.c | 20 +++++++++----
drivers/usb/core/usb.h | 1
6 files changed, 111 insertions(+), 21 deletions(-)
This gets rid of some inconsistently duplicated logic to resume interfaces.
Similar code was in both finish_port_resume() and in usb_generic_resume().
Now there is just one copy of that code, accessed regardless of whether
CONFIG_USB_SUSPEND is enabled. Fault handling is also more consistent.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch removes the extra usb_suspend_device() parameter. The original
reason to pass that parameter was so that this routine could suspend any
active children. A previous patch removed that functionality ... leaving
no reason to pass the parameter. A close analogy is pci_set_power_state,
which doesn't need a pm_message_t either.
On the internal code path that comes through the driver model, the parameter
is now used to distinguish cases where USB devices need to "freeze" but not
suspend. It also checks for an error case that's accessible through sysfs:
attempting to suspend a device before its interfaces (or for hubs, ports).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/usb/core/hub.c | 34 +++++++++++++++++++++-------------
drivers/usb/core/usb.c | 23 +++++++++++++++++++++--
drivers/usb/host/ehci-hcd.c | 2 +-
drivers/usb/host/isp116x-hcd.c | 2 +-
drivers/usb/host/ohci-pci.c | 2 +-
include/linux/usb.h | 2 +-
6 files changed, 46 insertions(+), 19 deletions(-)
This patch removes some recursion in the CONFIG_USB_SUSPEND logic, which
suspended children (of devices or hubs) that weren't already suspended.
When it sees such cases, suspend now just fails cleanly.
That logic was not needed during system-wide sleep state transitions; and
given the current notions of how to manage selective suspend transitions,
we don't want it there either. Where it was particularly handy was coping
with various limitations of the sysfs "echo -n N > power/state" support.
(These include assuming that "N" is always meaningful to the driver; and
that drivers can only transition to state N from state zero.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This updates the handling of power state for USB interfaces.
- Formalizes an existing invariant: interface "power state" is a boolean:
ON when I/O is allowed, and FREEZE otherwise. It does so by defining
some inlined helpers, then using them.
- Adds a useful invariant: the only interfaces marked active are those
bound to non-suspended drivers. Later patches build on this invariant.
- Simplifies the interface driver API (and removes some error paths) by
removing the requirement that they record power state changes during
suspend and resume callbacks. Now usbcore does that.
A few drivers were simplified to address that last change.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/usb/core/hub.c | 33 +++++++++------------
drivers/usb/core/message.c | 1
drivers/usb/core/usb.c | 65 +++++++++++++++++++++++++++++++++----------
drivers/usb/core/usb.h | 18 +++++++++++
drivers/usb/input/hid-core.c | 2 -
drivers/usb/misc/usbtest.c | 10 ------
drivers/usb/net/pegasus.c | 2 -
drivers/usb/net/usbnet.c | 2 -
8 files changed, 85 insertions(+), 48 deletions(-)
This patch teaches "usb_device" about the new driver model wakeup support:
- It updates device wakeup capabilities when entering a configuration
with the WAKEUP attribute;
- During suspend processing it consults the policy bit to see
whether it should enable wakeup for that device. (This resolves
a FIXME to not assume the answer is always "yes"; some devices
lie about supporting remote wakeup.)
Support for root hubs and the HCDs is separate (and more complex).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This appears to help some folk, please merge.
This patch relaxes reset timings. There are some reports that it
helps make enumeration work better on some high speed devices.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Routine cases like handoff-to-companion shouldn't trigger diagnostics.
This gets rid of some recently added log spamming. It's routine for
hub_port_wait_reset() to return -ENOTCONN to indicate handoff from
highspeed hubs to companions, so an error message is incorrect.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This adds think_time to the usb_tt struct and sets it appropriately
(measured in ns); this can help us implement better split transaction
scheduling.
Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as554) makes the hub driver disconnect any child USB devices
when it is unbound from a hub. Normally this will never happen, but
there are a few oddball ways to unbind the hub driver while leaving the
children intact. For example, the new "unbind" sysfs attribute can be
used for this purpose.
Given that unbinding hubs with children is now safe, the patch also
removes the code that prevented people from doing so using usbfs.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as553) merely moves some code and deletes an unneeded test in
the hub driver. This is in preparation for the patch that follows.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch introduces a /sys/class/usb_device/ class
where every connected usb-device will show up:
tree /sys/class/usb_device/
/sys/class/usb_device/
|-- usb1.1
| |-- dev
| `-- device -> ../../../devices/pci0000:00/0000:00:1d.0/usb1
|-- usb2.1
| |-- dev
| `-- device -> ../../../devices/pci0000:00/0000:00:1d.1/usb2
...
The presence of the "dev" file lets udev create real device nodes.
kay@pim:~/src/linux-2.6> tree /dev/bus/usb/
/dev/bus/usb/
|-- 1
| `-- 1
|-- 2
| `-- 1
...
udev rule:
SUBSYSTEM="usb_device", PROGRAM="/sbin/usb_device %k", NAME="%c"
(echo $1 | /bin/sed 's/usb\([0-9]*\)\.\([0-9]*\)/bus\/usb\/\1\/\2/')
This makes libusb pick up the real nodes instead of the mounted usbfs:
export USB_DEVFS_PATH=/dev/bus/usb
Background:
All this makes it possible to manage usb devices with udev instead of
the devfs solution. We are currently working on a pam_console/resmgr
replacement driven by udev and a pam-helper. It applies ACL's to device
nodes, which is required for modern desktop functionalty like
"Fast User Switching" or multiple local login support.
New patch with its own major. I've succesfully disabled usbfs and use real
nodes only on my box. With: "export USB_DEVFS_PATH=/dev/bus/usb" libusb picks
up the udev managed nodes instead of reading usbfs files.
This makes udev to provide symlinks for libusb to pick up:
SUBSYSTEM="usb_device", PROGRAM="/sbin/usbdevice %k", SYMLINK="%c"
/sbin/usbdevice:
#!/bin/sh
echo $1 | /bin/sed 's/usbdev\([0-9]*\)\.\([0-9]*\)/bus\/usb\/\1\/\2/'
Signed-off-by: Kay Sievers <kay.sievers@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This adds type-checking to pm_message_t, so that people can't confuse it
with int or u32. It also allows us to fix "disk yoyo" during suspend (disk
spinning down/up/down).
[We've tried that before; since that cpufreq problems were fixed and I've
tried make allyes config and fixed resulting damage.]
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Alexander Nyberg <alexn@telia.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This one-liner fixes a test for interfaces that are already resumed.
It would be nice if this could get into 2.6.12, but it's not critical
since it only affects people doing selective (runtime) suspend/resume.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch removes the hub_set_power_budget routine, which was used by a
couple of HCDs to indicate that the root hub was running on battery power.
In its place is a new field added to struct usb_hcd, which HCDs can set
before the root hub is registered. Special-case code in the hub driver
knows to look at this field when configuring a root hub.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is a revised version of an earlier patch to add support to usbcore
for driving root hubs by interrupts rather than polling.
There's a temporary flag added to struct usb_hcd, marking devices whose
drivers are aware of the new mechanism. By default that flag doesn't get
set so drivers will continue to see the same polling behavior as before.
This way we can convert the HCDs one by one to use interrupt-based event
reporting, and the temporary flag can be removed when they're all done.
Also included is a small change to the hcd_disable_endpoint routine.
Although endpoints normally shouldn't be disabled while a controller is
suspended, it's legal to do so when the controller's driver is being
rmmod'ed.
Lastly the patch adds a new callback, .hub_irq_enable, for use by HCDs
where the root hub's port-change interrupts are level-triggered rather
than edge-triggered. The callback is invoked each time khubd has finished
processing a root hub, to let the HCD know that the interrupt can safely
be re-enabled.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
1. Establish a simple API for process freezing defined in linux/include/sched.h:
frozen(process) Check for frozen process
freezing(process) Check if a process is being frozen
freeze(process) Tell a process to freeze (go to refrigerator)
thaw_process(process) Restart process
frozen_process(process) Process is frozen now
2. Remove all references to PF_FREEZE and PF_FROZEN from all
kernel sources except sched.h
3. Fix numerous locations where try_to_freeze is manually done by a driver
4. Remove the argument that is no longer necessary from two function calls.
5. Some whitespace cleanup
6. Clear potential race in refrigerator (provides an open window of PF_FREEZE
cleared before setting PF_FROZEN, recalc_sigpending does not check
PF_FROZEN).
This patch does not address the problem of freeze_processes() violating the rule
that a task may only modify its own flags by setting PF_FREEZE. This is not clean
in an SMP environment. freeze(process) is therefore not SMP safe!
Signed-off-by: Christoph Lameter <christoph@lameter.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Get rid of a bunch of redundant NULL pointer checks in drivers/usb/*,
there's no need to check a pointer for NULL before calling kfree() on it.
Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Index: gregkh-2.6/drivers/usb/class/audio.c
===================================================================
This is the first of a few installments of PM API updates to match the
recent switch to "pm_message_t". This installment primarily affects
USB device drivers (for USB interfaces), and it changes the handful of
drivers which currently implement suspend methods:
- <linux/usb.h> and usbcore, signature change
- Some drivers only changed the signature, net effect this just
shuts up "sparse -Wbitwise":
* hid-core
* stir4200
- Two network drivers did that, and also grew slightly more
featureful suspend code ... they now properly shut down
their activities. (As should stir4200...)
* pegasus
* usbnet
Note that the Wake-On-Lan (WOL) support in pegasus doesn't yet work; looks
to me like it's missing a request to turn it on, vs just configuring it.
The ASIX code in usbnet also has WOL hooks that are ready to use; untested.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Index: gregkh-2.6/drivers/net/irda/stir4200.c
===================================================================
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
