This patch (as812) changes the kerneldoc comments explaining the return
values from queue_work(), queue_delayed_work(), and
queue_delayed_work_on(). The updated comments explain more accurately the
meaning of the return code and avoid suggesting that a 0 value means the
routine was unsuccessful.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This patch (as797) fixes device_add() in the driver core. It needs to
pay attention when the driver for a new device reports an error.
At the same time, since bus_remove_device() undoes the effects of both
bus_add_device() and bus_attach_device(), it needs to check whether
the bus_attach_device step failed.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as803) adds an unusual_devs entry for the Nokia 6234
mobile phone.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as800) straightens out the USB endpoint class device
creation routine, fixing a refcount bug in the process.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as799) fixes a nasty refcount error in the USB endpoint class.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as798) adds a workaround to uhci-hcd. At least one Asus
motherboard is wired in such a way that any device attached to a
suspended UHCI controller will prevent the system from entering
suspend-to-RAM by immediately waking it up. The only way around the
problem is to turn the controller off instead of suspending it.
This fixes Bugzilla #6193.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as796) adds an unusual_devs entry for the Nokia 6131, which
doesn't like large transfer sizes.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as762) changes the cpufreq_transition_notifier_list from a
blocking_notifier_head to an srcu_notifier_head. This will prevent errors
caused attempting to call down_read() to access the notifier chain at a
time when interrupts must remain disabled, during system suspend.
It's not clear to me whether this is really necessary; perhaps the chain
could be made into an atomic_notifier. However a couple of the callout
routines do use blocking operations, so this approach seems safer.
The head of the notifier chain needs to be initialized before use; this is
done by an __init routine at core_initcall time. If this turns out not to
be a good choice, it can easily be changed.
Signed-off-by: Alan Stern <[email protected]>
Cc: "Paul E. McKenney" <[email protected]>
Cc: Jesse Brandeburg <[email protected]>
Cc: Dave Jones <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Currently the init_srcu_struct() routine has no way to report out-of-memory
errors. This patch (as761) makes it return -ENOMEM when the per-cpu data
allocation fails.
The patch also makes srcu_init_notifier_head() report a BUG if a notifier
head can't be initialized. Perhaps it should return -ENOMEM instead, but
in the most likely cases where this might occur I don't think any recovery
is possible. Notifier chains generally are not created dynamically.
[[email protected]: avoid statement-with-side-effect in macro]
Signed-off-by: Alan Stern <[email protected]>
Acked-by: Paul E. McKenney <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This patch (as751) adds a new type of notifier chain, based on the SRCU
(Sleepable Read-Copy Update) primitives recently added to the kernel. An
SRCU notifier chain is much like a blocking notifier chain, in that it must
be called in process context and its callout routines are allowed to sleep.
The difference is that the chain's links are protected by the SRCU
mechanism rather than by an rw-semaphore, so calling the chain has
extremely low overhead: no memory barriers and no cache-line bouncing. On
the other hand, unregistering from the chain is expensive and the chain
head requires special runtime initialization (plus cleanup if it is to be
deallocated).
SRCU notifiers are appropriate for notifiers that will be called very
frequently and for which unregistration occurs very seldom. The proposed
"task notifier" scheme qualifies, as may some of the network notifiers.
Signed-off-by: Alan Stern <[email protected]>
Acked-by: Paul E. McKenney <[email protected]>
Acked-by: Chandra Seetharaman <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This patch (as776) adds a new chapter to Documentation/CodingStyle,
explaining the circumstances under which a function should return 0 for
failure and non-zero for success as opposed to a negative error code for
failure and 0 for success.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Strictly speaking, the Valid bit in SCSI sense data is supposed to
be set only when the Information field contains a valid number. This
patch (as793) turns off the Valid bit when the Information field
hasn't been set.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as790b) adds "autostop" support to ohci-hcd: the driver
will automatically stop the host controller when no devices have been
connected for at least one second. This feature is useful when the
USB autosuspend facility isn't available, such as when
CONFIG_USB_SUSPEND hasn't been set.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
The autosuspend technique used by ohci-hcd doesn't mesh well with the
newer USB core autosuspend code. This patch (as789) removes ohci-hcd's
autosuspend support. Now the driver will be usable, but it won't
automatically go into a low-power state when no devices are connected.
That's for a later patch.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Originally I didn't think any host controller driver would ever use
interrupts and polling at the same time, but it turns out ohci-hcd wants
to do exactly that. This patch (as788) makes it possible.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as758) fixes the "warn-unused-result" messages in dummy-hcd.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as787) creates a new workqueue thread to handle delayed
USB autosuspend requests. Previously the code used keventd. However
it turns out that the hub driver's suspend routine calls
flush_scheduled_work(), making it a poor candidate for running in
keventd (the call immediately deadlocks). The solution is to use a
new thread instead of keventd.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as794) adds an unusual_devs entry for the Nokia E60.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as786) removes a redundant test and fixes a problem
involving repeated system sleeps when CONFIG_USB_SUSPEND is not set.
During the first wakeup, the root hub's dev.power.power_state.event
field doesn't get updated, causing it not to be suspended during the
second sleep transition.
This takes care of the issue raised by Rafael J. Wysocki and Mattia
Dongili.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as741) makes the non-hub parts of usbcore actually use the
autosuspend facilities added by an earlier patch.
Devices opened through usbfs are autoresumed and then
autosuspended upon close.
Likewise for usb-skeleton.
Devices are autoresumed for usb_set_configuration.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as755b) fixes a bug in usbmon. Rather than assuming all
USB host controllers use DMA, the code will check the usb_bus data
structure. If DMA isn't used, we don't want to try peeking into a
non-existent DMA buffer!
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
As part of the ongoing program to flatten out the HCD bus-glue layer,
this patch (as771b) eliminates the hcpriv, release, and kref fields
from struct usb_bus. hcpriv and release were not being used for
anything worthwhile, and kref has been moved into the enclosing
usb_hcd structure.
Along with those changes, the patch gets rid of usb_bus_get and
usb_bus_put, replacing them with usb_get_hcd and usb_put_hcd.
The one interesting aspect is that the dev_set_drvdata call was
removed from usb_put_hcd, where it clearly doesn't belong. This means
the driver private data won't get reset to NULL. It shouldn't cause
any problems, since the private data is undefined when no driver is
bound.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as770b) introduces a new field to usb_bus: a flag
indicating whether or not the host controller uses DMA. This serves
to encapsulate the computation. It also means we will have only one
spot to update if the DMA API changes.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
All of the currently-supported USB host controller drivers use the HCD
bus-glue framework. As part of the program for flattening out the glue
layer, this patch (as769) removes the usb_operations structure. All
function calls now go directly to the HCD routines (slightly renamed
to remain within the "usb_" namespace).
The patch also removes usb_alloc_bus(), because it's not useful in the
HCD framework and it wasn't referenced anywhere.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
It's generally a bad idea for USB interface drivers to try to change a
device's configuration, and usbcore doesn't provide any way for them
to do it. However in a few exceptional circumstances it can make
sense. This patch (as767) adds a roundabout mechanism to help drivers
that may need it.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
The UFI specification doesn't permit devices to indicate non-existent
LUNs in the manner prescribed by the SCSI spec. This patch (as773)
sets a special flag so that the SCSI scanner will recognize these
devices and treat them specially.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Matthew Dharm <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
The inconsistent lock state problem in usbcore (the one that shows up
when an HCD is unloaded) comes down to two inter-related problems:
usb_rh_urb_dequeue() isn't set up to be called with interrupts
disabled.
hcd_endpoint_disable() doesn't wait for all URBs on the
endpoint's queue to complete.
The two problems are related because the one type of URB that isn't
likely to be complete when hcd_endpoint_disable() returns is a root-hub
URB. Right now usb_rh_urb_dequeue() waits for them to complete, and it
assumes interrupts are enabled so it can wait. But
hcd_endpoint_disable() calls it with interrupts disabled.
Now, it should be legal to unlink root-hub URBs with interrupts
disabled. The solution is to move the waiting into
hcd_endpoint_disable(), where it belongs. This patch (as754) does that.
It turns out to be completely safe to replace the del_timer_sync() with
a simple del_timer(). It doesn't matter if the timer routine is
running; hcd_root_hub_lock will synchronize the two threads and the
status URB will complete with an unlink error, as it should.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
The UHCI controller in my laptop takes longer to turn off the
Resume-Detect bit than the 4 us allowed by uhci-hcd. Presumably other
computers will have the same problem.
This patch (as752) increases the maximum delay to 10 us, which should be
plenty, and uses polling to avoid penalizing systems which can turn the
bit off more quickly.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Since usb_generic can be unbound from a USB device, we need to be able
to handle the possibility that a suspend or resume request arrives for a
device with no driver. This patch (as735) arranges things so that
resume requests will fail and suspend requests will use the standard USB
port-suspend code. Attempts to suspend or resume an unbound interface
are handled similarly (although the error caused by trying to resume an
unbound interface is dropped by the calling routine).
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Currently we rely on intf->dev.power.power_state.event for tracking
whether intf is suspended. This is not a reliable technique because
that value is owned by the PM core, not by usbcore. This patch (as718b)
adds a new flag so that we can accurately tell which interfaces are
suspended and which aren't.
At first one might think these flags aren't needed, since interfaces
will be suspended along with their devices. It turns out there are a
couple of intermediate situations where that's not quite true, such as
while processing a remote-wakeup request.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as716b) splits up the core suspend and resume routines into
two parts each: one for handling devices and one for handling
interfaces. The behavior of the parts should be the same as in the old
unified code.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as732) adds a usb_device_driver structure, for representing
drivers that manage an entire USB device as opposed to just an
interface. Support routines like usb_register_device_driver,
usb_deregister_device_driver, usb_probe_device, and usb_unbind_device
are also added.
Unlike an earlier version of this patch, the new code is type-safe. To
accomplish this, the existing struct driver embedded in struct
usb_driver had to be wrapped in an intermediate wrapper. This enables
the core to tell at runtime whether a particular struct driver belongs
to a device driver or to an interface driver.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This revised patch (as713b) moves a few routines among source files in
usbcore. Some driver-related code in usb.c (claiming interfaces and
matching IDs) is moved to driver.c, where it belongs. Also the
usb_generic stuff in driver.c is moved to a new source file: generic.c.
(That's the reason for revising the patch.) Although not very big now,
it will get bigger in a later patch.
None of the code has been changed; it has only been re-arranged.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as712b) is a slight revision of one submitted earlier. It
fixes the usb-skeleton example driver so that it won't try to submit
URBs after skel_disconnect() has returned. This could cause errors, if
the driver was unbound and then a different driver was bound to the
device. It also fixes a couple of small bugs in the skel_write()
routine.
The revised patch uses a slightly different test, suggested by Dave
Brownell, for determining whether to free a transfer buffer. It's a
little clearer than the earlier version.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as711b) is a revised version of an earlier submission. It
modifies the usbfs code to detect when a device has been unregistered from
usbfs, even if the device is still connected. Although this can't happen
now, it will be able to happen after the upcoming changes to usb_generic.
Nobody objected to this patch when it was submitted before, so it should
be okay to apply this version. The revision is merely to take into
account the changes introduced by as723, which touches the same driver.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
The usbfs code doesn't provide sufficient mutual exclusion among open,
release, and remove. Release vs. remove is okay because they both
acquire the device lock, but open is not exclusive with either one. All
three routines modify the udev->filelist linked list, so they must not
run concurrently.
Apparently someone gave this a minimum amount of thought in the past by
explicitly acquiring the BKL at the start of the usbdev_open routine.
Oddly enough, there's a comment pointing out that locking is unnecessary
because chrdev_open already has acquired the BKL.
But this ignores the point that the files in /proc/bus/usb/* are not
char device files; they are regular files and so they don't get any
special locking. Furthermore it's necessary to acquire the same lock in
the release and remove routines, which the code does not do.
Yet another problem arises because the same file_operations structure is
accessible through both the /proc/bus/usb/* and /dev/usb/usbdev* file
nodes. Even when one of them has been removed, it's still possible for
userspace to open the other. So simple locking around the individual
remove routines is insufficient; we need to lock the entire
usb_notify_remove_device notifier chain.
Rather than rely on the BKL, this patch (as723) introduces a new private
mutex for the purpose. Holding the BKL while invoking a notifier chain
doesn't seem like a good idea.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as737b) does a very small cleanup of core/sysfs.c by adding
the configuration_string attribute file to the existing attribute group
instead of treating it separately. It doesn't need this separate
treatment because unlike the other device string attributes, it changes
along with the active configuration.
The patch also fixes a simple typo (which, oddly enough, doesn't seem to
bother the compiler).
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as781) adds an entry to unusual_devs.h for the Lacie DVD+-RW
drive. Apparently its USB interface has requirements similar to the
Genesys Logic interface; it doesn't like data to be sent too soon after
a command.
This fixes Bugzilla #6817.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Phil Dibowitz <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
The klist utility routines currently call _put methods while holding a
spinlock. This is of course illegal; a put routine could try to
unregister a device and hence need to sleep.
No problems have arisen until now because in many cases klist removals
were done synchronously, so the _put methods were never actually used.
In other cases we may simply have been lucky.
This patch (as784) reworks the klist routines so that _put methods are
called only _after_ the klist's spinlock has been released.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as783) simplifies the driver core slightly by removing four
unnecessary _get and _put methods.
It is vital that when a driver is removed from its bus's klist of
registered drivers, or when a device is removed from a driver's klist
of bound devices, that the klist updates complete synchronously.
Otherwise the kernel might try binding an unregistered driver to a
newly-registered device, or adding a device to the klist for a new
driver before it has been removed from the old driver's klist.
Since the removals must be synchronous, they don't need to update any
reference counts. Hence the _get and _put methods can be dispensed
with.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
There is a potential deadlock in the driver core. It boils down to
the fact that bus_remove_device() calls klist_remove() instead of
klist_del(), thereby waiting until the reference count of the
klist_node in the bus's klist of devices drops to 0. The refcount
can't reach 0 so long as a modprobe process is trying to bind a new
driver to the device being removed, by calling __driver_attach(). The
problem is that __driver_attach() tries to acquire the device's
parent's semaphore, but the caller of bus_remove_device() is quite
likely to own that semaphore already.
It isn't sufficient just to replace klist_remove() with klist_del().
Doing so runs the risk that the device would remain on the bus's klist
of devices for some time, and so could be bound to another driver even
after it was unregistered. What's needed is a new way to distinguish
whether or not a device is registered, based on a criterion other than
whether its klist_node is linked into the bus's klist of devices. That
way driver binding can fail when the device is unregistered, even if
it is still linked into the klist.
This patch (as782) implements the solution, by adding a new bitflag to
indiate when a struct device is registered, by testing the flag before
allowing a driver to bind a device, and by changing the definition of
the device_is_registered() inline.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Sanitize the Vendor, Product, and Revision strings contained in an
INQUIRY result by setting all non-graphic or non-ASCII characters to ' '.
Since the standard disallows such characters, this will affect
only non-compliant devices.
To help maintain backward compatibility, NUL characters are treated
specially. They are taken as string terminators; they and all the
following characters are set to ' '. If some valid characters get
erased as a result... well, we weren't seeing them before so we haven't
lost anything.
The primary purpose of this change is to allow blacklist entries to
match devices with illegal Vendor or Product strings.
In addition, the patch updates a couple of function prototypes, giving
inq_result its correct type (unsigned char *).
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: James Bottomley <[email protected]>
When skipping to the last TD of an URB, go to the _last_ entry in the
list instead of the _first_ entry (as780). This fixes Bugzilla #6747
and possibly others.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Unlike other sorts of endpoint queues, Isochronous queues don't stop
when an error is encountered. This patch (as772) fixes the scanning
routine in uhci-hcd, to make it keep on going when it finds an Iso
error.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
The existing unusual_devs entry for the UCR-61S2B appears to have too
wide a revision range. It matches at least one device that doesn't
respond to the initialization sequence. Perhaps the sequence needs to
be updated, or perhaps something else can be done. For now, this patch
(as764) restricts the range to include only the revision mentioned in
the original comment.
This resolves (for now!) Bugzilla entry #6950.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Apparently some UHCI controllers change the value of the Short Packet
Detect (SPD) bit in the TD status word -- presumably when they receive a
short packet. This patch (as759) changes uhci-hcd to avoid assuming
that the bit is unchanged; in fact, the driver no longer looks at SPD at
all.
This fixes the second problem reported in Bugzilla #6752.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Here is another unusual_devs entry (as760) for another Nokia device,
this time the 3250.
From: Mario Rettig <[email protected]>
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Phil Dibowitz <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as756) fixes a bug in dummy-hcd found by the lockdep
checker. In one of the code paths, the driver did not disable
interrupts before calling a request completion routine.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as748) adds an unusual_devs entry for the Nokia E61 mobile
phone.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as745) adds an unusual_devs entry for the Nokia N91, just like
the entry for the N80 added a couple of weeks ago. Apparently Nokia isn't
using very good firmware these days...
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
My recent patch converting usb-storage to use
usb_reset_composite_device() added a bug, a race between reset and
disconnect. It was necessary to drop the private lock while executing a
reset, and if a disconnect occurs at that time it will cause a crash.
This patch (as722) fixes the problem by explicitly checking for an early
termination after executing each command.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
We all failed to notice that Franck's recent update to usb-storage allowed
an URB to complete after its context data was no longer valid. This patch
(as746) makes the driver wait for the URB to complete whenever there's a
timeout.
Although timeouts in usb-storage are relatively uncommon, they do occur.
Without this patch the code in 2.6.18-rc1 will fault within an interrupt
handler, which is not nice at all.
Signed-off-by: Alan Stern <[email protected]>
Cc: Greg KH <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
We have to be able to remove SCSI devices even when they are suspended, so
QUIESCE -> CANCEL must be a legal state transition. This patch (as727)
adds the transition to the state machine.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: James Bottomley <[email protected]>
Since raw_notifier chains don't benefit from any centralized locking
protections, they shouldn't suffer from the associated limitations. Under
some circumstances it might make sense for a raw_notifier callout routine
to unregister itself from the notifier chain. This patch (as678) changes
the notifier core to allow for such things.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Here is a patch (as720) adding an unusual_devs entry for the Nokia N80
mobile phone.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as707) improves the FSBR operation in uhci-hcd by turning it
off more quickly when it isn't needed. FSBR puts a noticeable load on a
computer's PCI bus, so it should be disabled as soon as possible when it
isn't in use. The patch leaves it running for only 10 ms after the last
URB stops using it, on the theory that this should be long enough for a
driver to submit another URB if it wants keep FSBR going.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as706) removes the private hc_inaccessible flag from
uhci-hcd. It's not needed because it conveys exactly the same
information as the generic HCD_FLAG_HW_ACCESSIBLE bit.
In its place goes a new flag recording whether the controller is dead.
The new code allows a complete device reset to resurrect a dead
controller (although usbcore doesn't yet implement such a facility).
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as704) adds an unusual_devs entry for the Nikon DSC D70s,
which uses a different Product ID from the D70. It also moves the entry
for the DSC E2000 up in the list, to preserve the numerical ordering.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as703) improves the error handling when a Set-Configuration
request fails. The old interfaces are all unregistered before the
request is sent, and if the request fails then we don't know what config
the device is using. So it makes no sense to leave actconfig pointing
to the old configuration with its invalid interfaces.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as702) makes usbhid use the new usb_reset_composite_device
API. Now HID interfaces can coexist with other interfaces on the same
device, and a reset can safely be requested by any of the drivers.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as701) modifies usb-storage to take advantage of the new
usb_reset_composite_device() API. Now we will be able to safely request
port resets even if other drivers are bound to a mass-storage device.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Now that usbhid automatically applies HID_QUIRK_NOGET to keyboards and
mice, we no longer need the blacklist entries that were present for no
other purpose. This patch (as698) removes them.
Signed-off-by: Alan Stern <[email protected]>
Acked-by: Vojtech Pavlik <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as693b) makes the usbtest driver report errors in the
isochronous bulk transfer tests instead of always returning 0. As an
arbitrary cutoff, an error is returned if more than 10% of the packet
transfers fail. It also stops a test immediately upon receiving an URB
submission error.
For a test harness, it's especially important to report when errors occur!
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as692) fixes a few memory leaks in some unimportant error
pathways of the gadgetfs driver.
Signed-off-by: Alan Stern <[email protected]>
Acked-by: David Brownell <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as691) fixes a few errors in the AIO interface for the
gadgetfs driver. Now requests will complete properly instead of hanging.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as690) does the same thing for ISO TDs as as680 did for
non-ISO TDs: free them as they are used rather than all at once when an
URB is complete. At the same time it fixes a minor buglet (I'm not
aware of it ever affecting anyone): An ISO TD should be retired when its
frame is over, regardless of whether or not the hardware has marked it
inactive.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as689) stores the period for periodic transfers (interrupt
and ISO) in the queue header. This is necessary for proper bandwidth
tracking (not yet implemented). It also makes the scheduling of ISO
transfers a bit more rigorous, with checks for out-of-bounds frame
numbers.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as688) fixes a small race in uhci-hcd. Because ISO queues
aren't controlled by queue headers, they can't be unlinked. Only
individual URBs can. So whenever multiple ISO URBs are dequeued, it's
necessary to make sure the hardware is done with each one. We can't
assume that dequeuing the first URB will suffice to unlink the entire
queue.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as687) changes uhci-hcd to keep track of frame numbers as
full-sized integers rather than 11-bit values. This makes them a lot
easier to handle and makes it possible to schedule beyond a 2-second
window, should anyone ever want to do so.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Some old Intel UHCI controllers have a bug that has shown up in a few
systems (the PIIX3 "Neptune" chip set). Until now there has not been
any simple way to work around the bug, but the lastest changes in
uhci-hcd have made it easy. This patch (as684) adds the work-around.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as683) re-implements Full-Speed Bandwidth Reclamation (FSBR)
properly. It keeps track of which endpoint queues have advanced, and
when none have advanced for a sufficiently long time, FSBR is turned
off. The next TD on each of the non-moving queues is modified to
generate an interrupt on completion, so that FSBR can be re-enabled as
soon as the hardware starts to make some progress.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as682) gets rid of the TD-removal list in uhci-hcd. It is
no longer needed because now TDs are not freed until we know the
hardware isn't using them. It also simplifies the code for adding and
removing TDs to/from URBs.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as681) moves some code for cleaning up after unlinked URBs
out of the general completion pathway into the unlinking pathway.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as680) frees non-isochronous TDs as they are used, rather
than all at once when an URB is complete. Although not a terribly
important change in itself, it opens the door to a later enhancement
that will reduce storage requirements by allocating only a limited
number of TDs at any time for each endpoint queue.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as679) combines the result routine for Control URBs with the
routine for Bulk/Interrupt URBs. Along the way I eliminated the
debugging printouts for Control transfers unless the debugging level is
set higher than 1. I also eliminated a long-unused (#ifdef'ed-out)
section that works around some buggy old APC BackUPS devices.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
It seems to be relatively common for USB keyboards and mice to dislike
being polled for reports. Since there's no need to poll a keyboard or
a mouse, this patch (as685) automatically sets the HID_QUIRK_NOGET flag
for devices that advertise themselves as either sort of device with boot
protocol support.
This won't cure all the problems since some devices don't support the
boot protocol, but it's simple and easy and it should fix quite a few
problems.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as676) fixes a small bug in uhci-hcd's enqueue routine. When
an URB is unlinked or gets an error and the completion handler queues
another URB for the same endpoint, the queue shouldn't be allowed to start
up again until the handler returns. Not even if the new URB is the only
one on its queue.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as675) simplifies uhci-hcd slightly by storing each endpoint's
type in the corresponding Queue Header structure.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
The net2280 board has an annoying habit of surviving soft reboots with
interrupts enabled. This patch (as674) adds a shutdown routine to the
driver so that the board can be put in a quiescent state.
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
This patch (as721) makes dev_info and related macros print the device's
bus name if the device doesn't have a driver, instead of printing just a
blank. If the device isn't on a bus either... well, then it does leave
a blank space. But it will be easier for someone else to change if they
want.
Cc: Matthew Wilcox <[email protected]>
Signed-off-by: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
From: Alan Stern <[email protected]>
This chain does it's own locking via the RTNL semaphore, and
can also run recursively so adding a new mutex here was causing
deadlocks.
Signed-off-by: David S. Miller <[email protected]>
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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Alan Stern