linux-toradex.git/kernel/irq, branch v3.0.26

genirq: Clear action->thread_mask if IRQ_ONESHOT is not set

2012-03-12T17:32:53+00:00

commit 52abb700e16a9aa4cbc03f3d7f80206cbbc80680 upstream.

Xommit ac5637611(genirq: Unmask oneshot irqs when thread was not woken)
fails to unmask when a !IRQ_ONESHOT threaded handler is handled by
handle_level_irq.

This happens because thread_mask is or'ed unconditionally in
irq_wake_thread(), but for !IRQ_ONESHOT interrupts never cleared.  So
the check for !desc->thread_active fails and keeps the interrupt
disabled.

Keep the thread_mask zero for !IRQ_ONESHOT interrupts.

Document the thread_mask magic while at it.

Reported-and-tested-by: Sven Joachim 
Reported-and-tested-by: Stefan Lippers-Hollmann 
Signed-off-by: Thomas Gleixner 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

genirq: Handle pending irqs in irq_startup()

2012-03-01T00:34:29+00:00

commit b4bc724e82e80478cba5fe9825b62e71ddf78757 upstream.

An interrupt might be pending when irq_startup() is called, but the
startup code does not invoke the resend logic. In some cases this
prevents the device from issuing another interrupt which renders the
device non functional.

Call the resend function in irq_startup() to keep things going.

Reported-and-tested-by: Russell King 
Signed-off-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

genirq: Unmask oneshot irqs when thread was not woken

2012-03-01T00:34:29+00:00

commit ac5637611150281f398bb7a47e3fcb69a09e7803 upstream.

When the primary handler of an interrupt which is marked IRQ_ONESHOT
returns IRQ_HANDLED or IRQ_NONE, then the interrupt thread is not
woken and the unmask logic of the interrupt line is never
invoked. This keeps the interrupt masked forever.

This was not noticed as most IRQ_ONESHOT users wake the thread
unconditionally (usually because they cannot access the underlying
device from hard interrupt context). Though this behaviour was nowhere
documented and not necessarily intentional. Some drivers can avoid the
thread wakeup in certain cases and run into the situation where the
interrupt line s kept masked.

Handle it gracefully.

Reported-and-tested-by: Lothar Wassmann 
Signed-off-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

genirq: Fix race condition when stopping the irq thread

2011-12-09T16:52:46+00:00

commit 550acb19269d65f32e9ac4ddb26c2b2070e37f1c upstream.

In irq_wait_for_interrupt(), the should_stop member is verified before
setting the task's state to TASK_INTERRUPTIBLE and calling schedule().
In case kthread_stop sets should_stop and wakes up the process after
should_stop is checked by the irq thread but before the task's state
is changed, the irq thread might never exit:

kthread_stop                    irq_wait_for_interrupt
------------                    ----------------------

                                 ...
...                              while (!kthread_should_stop()) {
kthread->should_stop = 1;
wake_up_process(k);
wait_for_completion(&kthread->exited);
...
                                     set_current_state(TASK_INTERRUPTIBLE);

                                     ...

                                     schedule();
                                 }

Fix this by checking if the thread should stop after modifying the
task's state.

[ tglx: Simplified it a bit ]

Signed-off-by: Ido Yariv 
Link: http://lkml.kernel.org/r/1322740508-22640-1-git-send-email-ido@wizery.com
Signed-off-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

genirq: fix regression in irqfixup, irqpoll

2011-12-09T16:52:27+00:00

commit 52553ddffad76ccf192d4dd9ce88d5818f57f62a upstream.

Commit fa27271bc8d2("genirq: Fixup poll handling") introduced a
regression that broke irqfixup/irqpoll for some hardware configurations.

Amidst reorganizing 'try_one_irq', that patch removed a test that
checked for 'action->handler' returning IRQ_HANDLED, before acting on
the interrupt.  Restoring this test back returns the functionality lost
since 2.6.39.  In the current set of tests, after 'action' is set, it
must precede '!action->next' to take effect.

With this and my previous patch to irq/spurious.c, c75d720fca8a, all
IRQ regressions that I have encountered are fixed.

Signed-off-by: Edward Donovan 
Reported-and-tested-by: Rogério Brito 
Cc: Thomas Gleixner 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

genirq: Fix irqfixup, irqpoll regression

2011-11-26T17:09:51+00:00

commit c75d720fca8a91ce99196d33adea383621027bf2 upstream.

commit d05c65fff0 ("genirq: spurious: Run only one poller at a time")
introduced a regression, leaving the boot options 'irqfixup' and
'irqpoll' non-functional. The patch placed tests in each function, to
exit if the function is already running. The test in 'misrouted_irq'
exited when it should have proceeded, effectively disabling
'misrouted_irq' and 'poll_spurious_irqs'.

The check for an already running poller needs to be "!= 1" not "== 1"
as "1" is the value when the first poller starts running.

Signed-off-by: Edward Donovan 
Cc: maciej.rutecki@gmail.com
Link: http://lkml.kernel.org/r/1320175784-6745-1-git-send-email-edward.donovan@numble.net
Signed-off-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

genirq: Add IRQF_RESUME_EARLY and resume such IRQs earlier

2011-11-11T17:35:54+00:00

commit 9bab0b7fbaceec47d32db51cd9e59c82fb071f5a upstream.

This adds a mechanism to resume selected IRQs during syscore_resume
instead of dpm_resume_noirq.

Under Xen we need to resume IRQs associated with IPIs early enough
that the resched IPI is unmasked and we can therefore schedule
ourselves out of the stop_machine where the suspend/resume takes
place.

This issue was introduced by 676dc3cf5bc3 "xen: Use IRQF_FORCE_RESUME".

Signed-off-by: Ian Campbell 
Cc: Rafael J. Wysocki 
Cc: Jeremy Fitzhardinge 
Cc: xen-devel 
Cc: Konrad Rzeszutek Wilk 
Link: http://lkml.kernel.org/r/1318713254.11016.52.camel@dagon.hellion.org.uk
Signed-off-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

genirq: Make irq_shutdown() symmetric vs. irq_startup again

2011-10-03T18:40:27+00:00

commit ed585a651681e822089087b426e6ebfb6d3d9873 upstream.

If an irq_chip provides .irq_shutdown(), but neither of .irq_disable() or
.irq_mask(), free_irq() crashes when jumping to NULL.
Fix this by only trying .irq_disable() and .irq_mask() if there's no
.irq_shutdown() provided.

This revives the symmetry with irq_startup(), which tries .irq_startup(),
.irq_enable(), and irq_unmask(), and makes it consistent with the comment for
irq_chip.irq_shutdown() in , which says:

 * @irq_shutdown:	shut down the interrupt (defaults to ->disable if NULL)

This is also how __free_irq() behaved before the big overhaul, cfr. e.g.
3b56f0585fd4c02d047dc406668cb40159b2d340 ("genirq: Remove bogus conditional"),
where the core interrupt code always overrode .irq_shutdown() to
.irq_disable() if .irq_shutdown() was NULL.

Signed-off-by: Geert Uytterhoeven 
Cc: linux-m68k@lists.linux-m68k.org
Link: http://lkml.kernel.org/r/1315742394-16036-2-git-send-email-geert@linux-m68k.org
Signed-off-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

genirq: Fix wrong bit operation

2011-08-29T20:29:06+00:00

commit 1dd75f91ae713049eb6baaa640078f3a6549e522 upstream.

(!msk & 0x01) should be !(msk & 0x01)

Signed-off-by: Jonghwan Choi 
Link: http://lkml.kernel.org/r/1311229754-6003-1-git-send-email-jhbird.choi@samsung.com
Signed-off-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

genirq: replace irq_gc_ack() with {set,clr}_bit variants (fwd)

2011-07-07T16:02:26+00:00

This fixes a regression introduced by e59347a "arm: orion:
Use generic irq chip".

Depending on the device, interrupts acknowledgement is done by setting
or by clearing a dedicated register. Replace irq_gc_ack() with some
{set,clr}_bit variants allows to handle both cases.

Note that this patch affects the following SoCs: Davinci, Samsung and
Orion. Except for this last, the change is minor: irq_gc_ack() is just
renamed into irq_gc_ack_set_bit().

For the Orion SoCs, the edge GPIO interrupts support is currently
broken. irq_gc_ack() try to acknowledge a such interrupt by setting
the corresponding cause register bit. The Orion GPIO device expect the
opposite. To fix this issue, the irq_gc_ack_clr_bit() variant is used.

Tested on Network Space v2.

Reported-by: Joey Oravec 
Signed-off-by: Simon Guinot 
Signed-off-by: Arnd Bergmann