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>
Remove includes of asm/hardware.h in addition to asm/arch/hardware.h.
Then, since asm/hardware.h only exists to include asm/arch/hardware.h,
update everything to directly include asm/arch/hardware.h and remove
asm/hardware.h.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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>
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>
The previous model had the module_init & module_exit function in the
bus glue .c files themselves. That's a problem if several glues need
to be selected at once and the driver is built has module. This case
is quite common in embedded system where you want to handle both the
integrated ohci controller and some extra controller on PCI.
The ohci-hcd.c file now provide the module_init & module_exit and
appropriate driver registering/unregistering is done conditionally,
using #ifdefs.
Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is an OHCI cleanup patch ... it removes a lot of erroneous whitespace
(space before tab, at end of line) as well as the obsolete inline changelog.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This teaches OHCI to use the root hub status change (RHSC) IRQ, bypassing
root hub timers most of the time and switching over to the "new" root hub
polling scheme. It's complicated by the fact that implementations of OHCI
trigger and ack that IRQ differently (the spec is vague there).
Avoiding root hub timers helps mechanisms like "dynamic tick" leave the
CPU in lowpower modes for longer intervals.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as580) is perhaps the only result from the long discussion I
had with David about his changes to the root-hub suspend/resume code. It
renames the hub_suspend and hub_resume methods in struct usb_hcd to
bus_suspend and bus_resume. These are more descriptive names, since the
methods really do suspend or resume an entire USB bus, and less likely to
be confused with the hub_suspend and hub_resume routines in hub.c.
It also takes David's advice about removing the layer of bus glue, where
those methods are called. And it implements a related change that David
made to the other HCDs but forgot to put into dummy_hcd.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This cleans up a small recent FIXME, ensuring that all the HCDs provide
root hub suspend/resume methods. It also wraps the calls to those root
suspend routines just like on the PCI "USB_SUSPEND not defined" cases,
so non-PCI bus glue won't be as tempted to behave very differently.
Several of the SOC based OHCI drivers forgot to list those methods;
the patch also adds those missing declarations.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/usb/core/hcd.c | 42 +++++++++++++++++++++++++---------------
drivers/usb/host/ohci-au1xxx.c | 5 ++++
drivers/usb/host/ohci-lh7a404.c | 5 ++++
drivers/usb/host/ohci-pxa27x.c | 1
drivers/usb/host/ohci-s3c2410.c | 1
drivers/usb/host/ohci-sa1111.c | 1
6 files changed, 40 insertions(+), 15 deletions(-)
This simplifies some of the PM-related #ifdeffing by recognizing
that USB_SUSPEND depends on PM. Also, OHCI drivers were often
testing for USB_SUSPEND when they should have tested just PM.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/usb/core/hcd.c | 2 ++
drivers/usb/host/ohci-hcd.c | 2 +-
drivers/usb/host/ohci-hub.c | 4 ++--
drivers/usb/host/ohci-omap.c | 2 +-
drivers/usb/host/ohci-pci.c | 2 +-
drivers/usb/host/ohci-ppc-soc.c | 4 ++--
drivers/usb/host/ohci-pxa27x.c | 2 +-
drivers/usb/host/ohci-s3c2410.c | 3 +--
drivers/usb/host/ohci-sa1111.c | 2 +-
9 files changed, 12 insertions(+), 11 deletions(-)
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Alan Stern