diff options
| author | Marc Zyngier <marc.zyngier@arm.com> | 2017-11-09 14:17:59 +0000 |
|---|---|---|
| committer | Marc Zyngier <marc.zyngier@arm.com> | 2017-11-10 09:49:48 +0000 |
| commit | 4f8413a3a799c958f7a10a6310a451e6b8aef5ad (patch) | |
| tree | afefcfa5b445e3cbd33d7511c603c5e6c02cf000 /kernel/irq | |
| parent | 666740fde412567aa0a8ea251ffee3004a6fa3a6 (diff) | |
| download | linux-4f8413a3a799c958f7a10a6310a451e6b8aef5ad.tar.bz2 | |
genirq: Track whether the trigger type has been set
When requesting a shared interrupt, we assume that the firmware
support code (DT or ACPI) has called irqd_set_trigger_type
already, so that we can retrieve it and check that the requester
is being reasonnable.
Unfortunately, we still have non-DT, non-ACPI systems around,
and these guys won't call irqd_set_trigger_type before requesting
the interrupt. The consequence is that we fail the request that
would have worked before.
We can either chase all these use cases (boring), or address it
in core code (easier). Let's have a per-irq_desc flag that
indicates whether irqd_set_trigger_type has been called, and
let's just check it when checking for a shared interrupt.
If it hasn't been set, just take whatever the interrupt
requester asks.
Fixes: 382bd4de6182 ("genirq: Use irqd_get_trigger_type to compare the trigger type for shared IRQs")
Cc: stable@vger.kernel.org
Reported-and-tested-by: Petr Cvek <petrcvekcz@gmail.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'kernel/irq')
| -rw-r--r-- | kernel/irq/manage.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index e667912d0e9c..21e04e780be4 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -1228,7 +1228,18 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) * set the trigger type must match. Also all must * agree on ONESHOT. */ - unsigned int oldtype = irqd_get_trigger_type(&desc->irq_data); + unsigned int oldtype; + + /* + * If nobody did set the configuration before, inherit + * the one provided by the requester. + */ + if (irqd_trigger_type_was_set(&desc->irq_data)) { + oldtype = irqd_get_trigger_type(&desc->irq_data); + } else { + oldtype = new->flags & IRQF_TRIGGER_MASK; + irqd_set_trigger_type(&desc->irq_data, oldtype); + } if (!((old->flags & new->flags) & IRQF_SHARED) || (oldtype != (new->flags & IRQF_TRIGGER_MASK)) || |