Commit graph

9 commits

Author SHA1 Message Date
Alan Stern
b5fb454f69 USB: automatically enable RHSC interrupts
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 <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-21 10:26:38 -07:00
Kay Sievers
7071a3ce0c USB: usb dev_name() instead of dev->bus_id
The bus_id field is going away, use the dev_name() function instead.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 15:15:46 -07:00
Linus Torvalds
09ca8adbe9 Revert "USB: don't explicitly reenable root-hub status interrupts"
This reverts commit e872154921.

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 <arvidjaar@mail.ru>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: David Brownell <david-b@pacbell.net>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-06 10:27:25 -07:00
Alan Stern
e872154921 USB: don't explicitly reenable root-hub status interrupts
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 <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:53 -07:00
Alan Stern
43bbb7e015 USB: OHCI: host-controller resumes leave root hub suspended
Drivers in the ohci-hcd family should perform certain tasks whenever
their controller device is resumed.  These include checking for loss
of power during suspend, turning on port power, and enabling interrupt
requests.

Until now these jobs have been carried out when the root hub is
resumed, not when the controller is.  Many drivers work around the
resulting awkwardness by automatically resuming their root hub
whenever the controller is resumed.  But this is wasteful and
unnecessary.

To simplify the situation, this patch (as1066) adds a new core
routine, ohci_finish_controller_resume(), which can be used by all the
OHCI-variant drivers.  They can call the new routine instead of
resuming their root hubs.  And ohci-pci.c can call it instead of using
its own special-purpose handler.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:48 -07:00
Alan Stern
7be7d74187 USB: clarify usage of hcd->suspend/resume methods
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 <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-24 21:16:48 -07:00
Alan Stern
442258e2ff USB: use IRQF_DISABLED for HCD interrupt handlers
Host controller IRQs are supposed to be serviced with interrupts
disabled.  This patch (as1026) adds an IRQF_DISABLED flag to all the
controller drivers that lack it.  It also replaces the
spin_lock_irqsave() and spin_unlock_irqrestore() calls in uhci_irq()
with simple spin_lock() and spin_unlock().

This fixes Bugzilla #9335.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-12-17 10:47:15 -08:00
Al Viro
4735b37cf4 Fix ohci-ssb with !CONFIG_PM
ohci_bus_{suspend,resume} exists only if we have CONFIG_PM; do the same
thing as other subdrivers...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-13 18:18:30 -07:00
Michael Buesch
c604e85148 USB: ohci SSB bus glue
This adds SSB bus glue for the USB OHCI HCD. 

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-12 14:55:33 -07:00