linux.git/drivers/usb/core/hcd.h, branch v2.6.26

Revert "USB: don't explicitly reenable root-hub status interrupts"

2008-07-06T17:27:25+00:00

This reverts commit e872154921a6b5256a3c412dd69158ac0b135176.

Andrey Borzenkov reports that it resulted in a totally hung machine for
him when loading the OHCI driver.  Extensive netconsole capture with
SysRq output shows that modprobe gets stuck in ohci_hub_status_data()
when probing and enabling the OHCI controller, see for example

	http://lkml.org/lkml/2008/7/5/236

for an analysis.

The problem appears to be an interrupt flood triggered by the commit
that gets reverted, and Andrey confirmed that the revert makes things
work for him again.

Reported-and-tested-by: Andrey Borzenkov 
Acked-by: Alan Stern 
Acked-by: David Brownell 
Cc: Greg Kroah-Hartman 
Signed-off-by: Linus Torvalds

USB: EHCI: suppress unwanted error messages

2008-05-29T20:59:03+00:00

This patch (as1096) fixes an annoying problem: When a full-speed or
low-speed device is plugged into an EHCI controller, it fails to
enumerate at high speed and then is handed over to the companion
controller.  But usbcore logs a misleading and unwanted error message
when the high-speed enumeration fails.

The patch adds a new HCD method, port_handed_over, which asks whether
a port has been handed over to a companion controller.  If it has, the
error message is suppressed.

Signed-off-by: Alan Stern 
CC: David Brownell 
Signed-off-by: Greg Kroah-Hartman

USB: don't explicitly reenable root-hub status interrupts

2008-04-25T04:16:53+00:00

This patch (as1069b) 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: clarify usage of hcd->suspend/resume methods

2008-04-25T04:16:48+00:00

The .suspend and .resume method pointers in struct usb_hcd have not
been fully understood by host-controller driver writers.  They are
meant for use with PCI controllers; other platform-specific drivers
generally should not refer to them.

To try and clarify matters, this patch (as1065) renames those methods
to .pci_suspend and .pci_resume.  It eliminates corresponding dead code
and bogus references in the ohci-ssb and u132-hcd drivers.

Signed-off-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

USB: root hubs don't lie about their number of TTs

2008-04-25T04:16:48+00:00

Currently EHCI root hubs enumerate with a bDeviceProtocol code
indicating that they possess a Transaction Translator.  However the
vast majority of controllers do not; they rely on a companion
controller to handle full- and low-speed communications.  This patch
(as1064) changes the root-hub device descriptor to match the actual
situation.

Signed-off-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

USB: defines for USB "Link Power Management" (LPM) ECN

2008-04-25T04:16:34+00:00

There's a new PM-related change notice for the USB 2.0 specification
called "Link Power Management" (LPM).  It defines a new "L1 Suspend"
state which resembles the current (L2) suspend state, except that it
can be entered and exited much more quickly.  It should thus be more
useful for runtime PM, even though it doesn't mandate reduced power
draw from VBUS.

This patch provides the relevant #defines for usbcore.  Actually
implementing these mechanisms requires host silicon that can generate
new USB packets, plus hubs handling some new requests and peripherals
which understand the new packets.

Signed-off-by: David Brownell 
Signed-off-by: Greg Kroah-Hartman

USB: fix codingstyle issues in drivers/usb/core/*.h

2008-02-01T22:35:07+00:00

Fixes a number of coding style issues in the USB internal header files.

Signed-off-by: Greg Kroah-Hartman

usb: dma bounce buffer support

2008-02-01T22:35:05+00:00

usb: dma bounce buffer support V4

This patch adds dma bounce buffer support to the usb core. These buffers
can be enabled with the HCD_LOCAL_MEM flag, and they make sure that all data
passed to the host controller is allocated using dma_alloc_coherent().

Signed-off-by: Magnus Damm 
Acked-by: Alan Stern 
Acked-by: David Brownell 
Signed-off-by: Greg Kroah-Hartman

USB: force handover port to companion when hub_port_connect_change fails

2008-02-01T22:34:52+00:00

This patch hands over the port to the companion when the
hub_port_connect_change fails.

Signed-off-by: Balaji Rao 
Signed-off-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

USB: mutual exclusion for EHCI init and port resets

2007-10-12T21:55:34+00:00

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 
Acked-by: David Brownell 
Cc: David Miller 
Cc: Dely L Sy 
Signed-off-by: Greg Kroah-Hartman