linux.git/drivers/usb/core/hcd.c, branch v3.0

USB: remove remaining usages of hcd->state from usbcore and fix regression

2011-05-19T23:34:04+00:00

This patch (as1467) removes the last usages of hcd->state from
usbcore.  We no longer check to see if an interrupt handler finds that
a controller has died; instead we rely on host controller drivers to
make an explicit call to usb_hc_died().

This fixes a regression introduced by commit
9b37596a2e860404503a3f2a6513db60c296bfdc (USB: move usbcore away from
hcd->state).  It used to be that when a controller shared an IRQ with
another device and an interrupt arrived while hcd->state was set to
HC_STATE_HALT, the interrupt handler would be skipped.  The commit
removed that test; as a result the current code doesn't skip calling
the handler and ends up believing the controller has died, even though
it's only temporarily stopped.  The solution is to ignore HC_STATE_HALT
following the handler's return.

As a consequence of this change, several of the host controller
drivers need to be modified.  They can no longer implicitly rely on
usbcore realizing that a controller has died because of hcd->state.
The patch adds calls to usb_hc_died() in the appropriate places.

The patch also changes a few of the interrupt handlers.  They don't
expect to be called when hcd->state is equal to HC_STATE_HALT, even if
the controller is still alive.  Early returns were added to avoid any
confusion.

Signed-off-by: Alan Stern 
Tested-by: Manuel Lauss 
CC: Rodolfo Giometti 
CC: Olav Kongas 
CC: 
Signed-off-by: Greg Kroah-Hartman

usb/hcd: don't return 0 on error in usb_add_hcd()

2011-04-30T00:24:35+00:00

If USB type detections fails, we run into default and return 0.

Signed-off-by: Sebastian Andrzej Siewior 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

USB: Fix unplug of device with active streams

2011-04-13T23:57:33+00:00

If I unplug a device while the UAS driver is loaded, I get an oops
in usb_free_streams().  This is because usb_unbind_interface() calls
usb_disable_interface() which calls usb_disable_endpoint() which sets
ep_out and ep_in to NULL.  Then the UAS driver calls usb_pipe_endpoint()
which returns a NULL pointer and passes an array of NULL pointers to
usb_free_streams().

I think the correct fix for this is to check for the NULL pointer
in usb_free_streams() rather than making the driver check for this
situation.  My original patch for this checked for dev->state ==
USB_STATE_NOTATTACHED, but the call to usb_disable_interface() is
conditional, so not all drivers would want this check.

Note from Sarah Sharp: This patch does avoid a potential dereference,
but the real fix (which will be implemented later) is to set the
.soft_unbind flag in the usb_driver structure for the UAS driver, and
all drivers that allocate streams.  The driver should free any streams
when it is unbound from the interface.  This avoids leaking stream rings
in the xHCI driver when usb_disable_interface() is called.

This should be queued for stable trees back to 2.6.35.

Signed-off-by: Matthew Wilcox 
Signed-off-by: Sarah Sharp 
Cc: stable@kernel.org

Fix common misspellings

2011-03-31T14:26:23+00:00

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi

USB: Set usb_hcd->state and flags for shared roothubs.

2011-03-14T01:23:33+00:00

The hcd->flags are in a sorry state.  Some of them are clearly specific to
the particular roothub (HCD_POLL_RH, HCD_POLL_PENDING, and
HCD_WAKEUP_PENDING), but some flags are related to PCI device state
(HCD_HW_ACCESSIBLE and HCD_SAW_IRQ).  This is an issue when one PCI device
can have two roothubs that share the same IRQ line and hardware.

Make sure to set HCD_FLAG_SAW_IRQ for both roothubs when an interrupt is
serviced, or an URB is unlinked without an interrupt.  (We can't tell if
the host actually serviced an interrupt for a particular bus, but we can
tell it serviced some interrupt.)

HCD_HW_ACCESSIBLE is set once by usb_add_hcd(), which is set for both
roothubs as they are added, so it doesn't need to be modified.
HCD_POLL_RH and HCD_POLL_PENDING are only checked by the USB core, and
they are never set by the xHCI driver, since the roothub never needs to be
polled.

The usb_hcd's state field is a similar mess.  Sometimes the state applies
to the underlying hardware: HC_STATE_HALT, HC_STATE_RUNNING, and
HC_STATE_QUIESCING.  But sometimes the state refers to the roothub state:
HC_STATE_RESUMING and HC_STATE_SUSPENDED.

Alan Stern recently made the USB core not rely on the hcd->state variable.
Internally, the xHCI driver still checks for HC_STATE_SUSPENDED, so leave
that code in.  Remove all references to HC_STATE_HALT, since the xHCI
driver only sets and doesn't test those variables.  We still have to set
HC_STATE_RUNNING, since Alan's patch has a bug that means the roothub
won't get registered if we don't set that.

Alan's patch made the USB core check a different variable when trying to
determine whether to suspend a roothub.  The xHCI host has a split
roothub, where two buses are registered for one PCI device.  Each bus in
the xHCI split roothub can be suspended separately, but both buses must be
suspended before the PCI device can be suspended.  Therefore, make sure
that the USB core checks HCD_RH_RUNNING() for both roothubs before
suspending the PCI host.

Signed-off-by: Sarah Sharp

usb: Make core allocate resources per PCI-device.

2011-03-14T01:23:06+00:00

Introduce the notion of a PCI device that may be associated with more than
one USB host controller driver (struct usb_hcd).  This patch is the start
of the work to separate the xHCI host controller into two roothubs: a USB
3.0 roothub with SuperSpeed-only ports, and a USB 2.0 roothub with
HS/FS/LS ports.

One usb_hcd structure is designated to be the "primary HCD", and a pointer
is added to the usb_hcd structure to keep track of that.  A new function
call, usb_hcd_is_primary_hcd() is added to check whether the USB hcd is
marked as the primary HCD (or if it is not part of a roothub pair).  To
allow the USB core and xHCI driver to access either roothub in a pair, a
"shared_hcd" pointer is added to the usb_hcd structure.

Add a new function, usb_create_shared_hcd(), that does roothub allocation
for paired roothubs.  It will act just like usb_create_hcd() did if the
primary_hcd pointer argument is NULL.  If it is passed a non-NULL
primary_hcd pointer, it sets usb_hcd->shared_hcd and usb_hcd->primary_hcd
fields.  It will also skip the bandwidth_mutex allocation, and set the
secondary hcd's bandwidth_mutex pointer to the primary HCD's mutex.

IRQs are only allocated once for the primary roothub.

Introduce a new usb_hcd driver flag that indicates the host controller
driver wants to create two roothubs.  If the HCD_SHARED flag is set, then
the USB core PCI probe methods will allocate a second roothub, and make
sure that second roothub gets freed during rmmod and in initialization
error paths.

When usb_hc_died() is called with the primary HCD, make sure that any
roothubs that share that host controller are also marked as being dead.

Signed-off-by: Sarah Sharp

usb: Store bus type in usb_hcd, not in driver flags.

2011-03-14T01:07:15+00:00

The xHCI driver essentially has both a USB 2.0 and a USB 3.0 roothub.  So
setting the HCD_USB3 bits in the hcd->driver->flags is a bit misleading.
Add a new field to usb_hcd, bcdUSB.  Store the result of
hcd->driver->flags & HCD_MASK in it.  Later, when we have the xHCI driver
register the two roothubs, we'll set the usb_hcd->bcdUSB field to HCD_USB2
for the USB 2.0 roothub, and HCD_USB3 for the USB 3.0 roothub.

Signed-off-by: Sarah Sharp

usb: Change usb_hcd->bandwidth_mutex to a pointer.

2011-03-14T01:07:14+00:00

Change the bandwith_mutex in struct usb_hcd to a pointer.  This will allow
the pointer to be shared across usb_hcds for the upcoming work to split
the xHCI driver roothub into a USB 2.0/1.1 and a USB 3.0 bus.

Signed-off-by: Sarah Sharp

usb: Refactor irq enabling out of usb_add_hcd()

2011-03-14T01:07:14+00:00

Refactor out the code in usb_add_hcd() to request the IRQ line for the
HCD.  This will only need to be called once for the two xHCI roothubs, so
it's easier to refactor it into a function, rather than wrapping the long
if-else block into another if statement.

Signed-off-by: Sarah Sharp

usb: Make USB 3.0 roothub have a SS EP comp descriptor.

2011-03-14T01:07:12+00:00

Make the USB 3.0 roothub registered by the USB core have a SuperSpeed
Endpoint Companion Descriptor after the interrupt endpoint.  All USB 3.0
devices are required to have this, and the USB 3.0 bus specification
(section 10.13.1) says which values the descriptor should have.

Signed-off-by: Sarah Sharp