linux.git/drivers/usb/core/hcd.c, 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: fix interrupt disabling for HCDs with shared interrupt handlers

2008-07-04T01:20:37+00:00

USB: fix interrupt disabling for HCDs with shared interrupt handlers

As has been discussed several times on LKML, IRQF_SHARED | IRQF_DISABLED
doesn't work reliably, i.e. a shared interrupt handler CAN'T be certain to
be called with interrupts disabled. Most USB HCD handlers use IRQF_DISABLED
and therefore havoc can break out if they share their interrupt with a
handler that doesn't use it.

On my test machine the yenta_socket interrupt handler (no IRQF_DISABLED)
was registered before ehci_hcd and one uhci_hcd instance. Therefore all
usb_hcd_irq() invocations for ehci_hcd and for one uhci_hcd instance
happened with interrupts enabled. That led to random lockups as USB core
HCD functions that acquire the same spinlock could be called twice
from interrupt handlers.

This patch updates usb_hcd_irq() to always disable/restore interrupts.
usb_add_hcd() will silently remove any IRQF_DISABLED requested from HCD code.

Signed-off-by: Stefan Becker 
Cc: stable 
Acked-by: David Brownell 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

USB: Core: fix race in device_create

2008-05-20T20:31:56+00:00

There is a race from when a device is created with device_create() and
then the drvdata is set with a call to dev_set_drvdata() in which a
sysfs file could be open, yet the drvdata will be NULL, causing all
sorts of bad things to happen.

This patch fixes the problem by using the new function,
device_create_drvdata().

Cc: Kay Sievers 
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: 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: fix comments of 2 functions in hcd.c

2008-04-25T04:16:45+00:00

Remove useless @type note for rh_string() and @r note for usb_hcd_irq()
since this two parameters were removed.

Signed-off-by: Ming Lei 
Signed-off-by: Greg Kroah-Hartman

USB: mark USB drivers as being GPL only

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

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

USB: use a real vendor and product id for root hubs

2008-02-01T22:35:06+00:00

Turns out that a company is out there using the vendor id of 0x0000 in
the wild, so use a real vendor/product id for the root hubs.

Now that the Linux Foundation has a real vendor id, we use that, and the
first product id:
	0x1d6b is the vendor id of the Linux Foundation
		0x0001 is the product id for Linux 1.1 root hubs
		0x0002 is the product id for Linux 2.0 root hubs

The usb.ids file has already been updated with these values.


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: Convert from class_device to device for USB core

2008-02-01T22:34:46+00:00

Convert from class_device to device for drivers/usb/core.

Signed-off-by: Tony Jones 
Cc: Kay Sievers 
Signed-off-by: Greg Kroah-Hartman