linux/drivers/usb/core, branch v2.6.27.7

USB: don't register endpoints for interfaces that are going away

2008-11-20T22:54:53Z

commit 352d026338378b1f13f044e33c1047da6e470056 upstream. This patch (as1155) fixes a bug in usbcore. When interfaces are deleted, either because the device was disconnected or because of a configuration change, the extra attribute files and child endpoint devices may get left behind. This is because the core removes them before calling device_del(). But during device_del(), after the driver is unbound the core will reinstall altsetting 0 and recreate those extra attributes and children. The patch prevents this by adding a flag to record when the interface is in the midst of being unregistered. When the flag is set, the attribute files and child devices will not be created. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman

USB: fix crash when URBs are unlinked after the device is gone

2008-11-07T03:05:38Z

commit cde217a556ec552d28ac9e136c5a94684a69ae94 upstream This patch (as1151) protects usbcore against drivers that try to unlink an URB after the URB's device or bus have been removed. The core does not currently check for this, and certain drivers can cause a crash if they are running while an HCD is unloaded. Certainly it would be best to fix the guilty drivers. But a little defensive programming doesn't hurt, especially since it appears that quite a few drivers need to be fixed. The patch prevents the problem by grabbing a reference to the device while an unlink is in progress and using a new spinlock to synchronize unlinks with device removal. (There's no need to acquire a reference to the bus as well, since the device structure itself keeps a reference to the bus.) In addition, the kerneldoc is updated to indicate that URBs should not be unlinked after the disconnect method returns. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman

USB: don't rebind drivers after failed resume or reset

2008-10-25T21:32:38Z

commit 6c6409459a18a825ce12ecb003d5686af61f7a2f upstream This patch (as1152) may help prevent some problems associated with the new policy of unbinding drivers that don't support suspend/resume or pre_reset/post_reset. If for any reason the resume or reset fails, and the device is logically disconnected, there's no point in trying to rebind the driver. So the patch checks for success before carrying out the unbind/rebind. There was a report from one user that this fixed a problem he was experiencing, but the details never became fully clear. In any case, adding these tests can't hurt. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman

USB: EHCI: log a warning if ehci-hcd is not loaded first

2008-10-22T21:21:22Z

commit 9beeee6584b9aa4f9192055512411484a2a624df upstream This patch (as1139) adds a warning to the system log whenever ehci-hcd is loaded after ohci-hcd or uhci-hcd. Nowadays most distributions are pretty good about not doing this; maybe the warning will help convince anyone still doing it wrong. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman

USB: revert recovery from transient errors

2008-09-23T20:58:10Z

This patch (as1135) essentially reverts the major parts of two earlier patches to usbcore, because they ended up causing a regression. Trying to recover from transient communication errors can lead to other problems, because operations that failed during the error period are not always retried. The simplest example is the initial Set-Config request sent after device enumeration; if it gets lost then it will not be retried and the device will remain unconfigured. This patch restores the old behavior in which any port disconnect or port disable causes the entire device structure to be removed, fixing a reported regression. Signed-off-by: Alan Stern Tested-by: Frans Pop Signed-off-by: Greg Kroah-Hartman

USB: fix hcd interrupt disabling

2008-09-23T20:58:06Z

Commit de85422b94ddb23c021126815ea49414047c13dc, 'USB: fix interrupt disabling for HCDs with shared interrupt handlers' changed usb_add_hcd() to strip IRQF_DISABLED from irqflags prior to calling request_irq() with the justification that such a removal was necessary for shared interrupts to work properly. Unfortunately, the change in that commit unconditionally removes the IRQF_DISABLED flag, causing problems on platforms that don't use a shared interrupt but require IRQF_DISABLED. This change adds a check for IRQF_SHARED prior to removing the IRQF_DISABLED flag. Fixes the PS3 system startup hang reported with recent Fedora and OpenSUSE kernels. Note that this problem is hidden when CONFIG_LOCKDEP=y (ps3_defconfig), as local_irq_enable_in_hardirq() is defined as a null statement for that config. CC: stable Signed-off-by: Geoff Levand Cc: Alan Stern Cc: Stefan Becker Signed-off-by: Greg Kroah-Hartman

USB: automatically enable RHSC interrupts

2008-08-21T17:26:38Z

This patch (as1069c) changes the way OHCI root-hub status-change interrupts are enabled. Currently a special HCD method, hub_irq_enable(), is called when the hub driver is finished using a root hub. This approach turns out to be subject to races, resulting in unnecessary polling. The patch does away with the method entirely. Instead, the driver automatically enables the RHSC interrupt when no more status changes are present. This scheme is safe with controllers using level-triggered semantics for their interrupt flags. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman

USB: Don't rebind before "complete" callback

2008-08-21T17:26:37Z

This patch (as1130) fixes an incompatibility between the new PM infrastructure and USB power management. We are not allowed to call drivers' probe routines during a system sleep transition between the "prepare" and "complete" callbacks, but that's exactly what we do when a driver doesn't have full suspend/resume support. Such drivers are unbound during the "suspend" call and reprobed during the "resume" call. The patch causes the reprobe step to be skipped if the "complete" callback hasn't been issued yet, i.e., if the interface's dev.power.status field is not equal to DPM_ON. Thus during the "resume" callback nothing bad will happen, and during the final "complete" callback the reprobing will occur as desired. This fixes the problem reported in Bugzilla #11263. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman

USB: Add new PM callback methods for USB

2008-08-21T17:26:37Z

This patch (as1129) adds support for the new PM callbacks to usbcore. The new callbacks merely invoke the same old USB power management routines as the old ones did. A minor improvement is that the callbacks are present only in the "USB-device" device_type structure, rather than in the bus_type structure. This way they will be invoked only for USB devices, not for USB interfaces. The core USB PM routines automatically handle suspending and resuming interfaces along with their devices. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman

USB: Defer Set-Interface for suspended devices

2008-08-21T17:26:36Z

This patch (as1128) fixes one of the problems related to the new PM infrastructure. We are not allowed to register new child devices during the middle of a system sleep transition, but unbinding a USB driver causes the core to automatically install altsetting 0 and thereby create new endpoint pseudo-devices. The patch fixes this problem (and the related problem that installing altsetting 0 will fail if the device is suspended) by deferring the Set-Interface call until some later time when it is legal and can succeed. Possible later times are: when a new driver is being probed for the interface, and when the interface is being resumed. Signed-off-by: Alan Stern Signed-off-by: Greg Kroah-Hartman