This patch (as954) implements a suggestion of David Brownell's. Now
the host controller drivers are responsible for linking and unlinking
URBs to/from their endpoint queues. This eliminates the possiblity of
strange situations where usbcore thinks an URB is linked but the HCD
thinks it isn't. It also means HCDs no longer have to check for URBs
being dequeued before they were fully enqueued.
In addition to the core changes, this requires changing every host
controller driver and the root-hub URB handler. For the most part the
required changes are fairly small; drivers have to call
usb_hcd_link_urb_to_ep() in their urb_enqueue method,
usb_hcd_check_unlink_urb() in their urb_dequeue method, and
usb_hcd_unlink_urb_from_ep() before giving URBs back. A few HCDs make
matters more complicated by the way they split up the flow of control.
In addition some method interfaces get changed. The endpoint argument
for urb_enqueue is now redundant so it is removed. The unlink status
is required by usb_hcd_check_unlink_urb(), so it has been added to
urb_dequeue.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: David Brownell <david-b@pacbell.net>
CC: Olav Kongas <ok@artecdesign.ee>
CC: Tony Olech <tony.olech@elandigitalsystems.com>
CC: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The ZF Micro OHCI controller exhibits unexpected behavior that seems to be
related to high load. Under certain conditions, the controller will
complete a TD, remove it from the endpoint's queue, and fail to add it to
the donelist. This causes the endpoint to appear to stop responding. Worse,
if the device is removed while in that state, OHCI will hang while waiting
for the orphaned TD to complete. The situation is not recoverable without
rebooting.
This fix enhances the scope of the existing OHCI_QUIRK_ZFMICRO flag:
1. A watchdog routine periodically scans the OHCI structures to check
for orphaned TDs. In these cases the TD is taken back from the
controller and completed normally.
2. If a device is removed while the endpoint is hung but before the
watchdog catches the situation, any outstanding TDs are taken back
from the controller in the 'sanitize' phase.
The ohci-hcd driver used to print "INTR_SF lossage" in this situation;
this changes it to the universally accurate "ED unlink timeout". Other
instances of this message presumably have different root causes.
Both this Compaq quirk and a NEC quirk are now properly compiled out for
non-PCI builds of this driver.
Signed-off-by: Mike Nuss <mike@terascala.com>
Signed-off-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 is a more correct fix for the way the ohci hcd was referencing pt_regs
in the unlink paths.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
This adds a quirk to the OHCI driver that lets it work with an old
Compaq implementation. It also removes some needless strings from
the non-debug version of the driver.
Signed-off-by: Chris Clayton <chris_clayton@f1internet.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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!
