Hi Hans, On 09/04/17 20:59, Hans de Goede wrote: > While writing a driver for the INT0002 ACPI device found on Intel > Bay and Cherry Trail devices I hit the following error: > > "genirq: Flags mismatch irq 9. 00000084 (INT0002) vs. 00000080 (acpi)" > > This is caused by drivers/acpi/osl.c first doing: > > request_irq(irq, acpi_irq, IRQF_SHARED, "acpi", acpi_irq) > > While the irqdata for the irq contains no trigger flags, resulting > in an irqaction with IRQF_TRIGGER_NONE. > > And then the INT0002 driver I'm working on calling platform_get_irq > which does: irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS); > > And then request_irq(irq, ..., IRQF_SHARED, ...) on the irq returned > by platform_get_irq causes the error quoted above. > > Arguably the genirq code should not hit the shared irq trigger-flags > mismatch code if the old irqaction has IRQF_TRIGGER_NONE as flags. > > This patch is an attempt at fixing this, but I'm not sure it is the > right fix, hence it RFC status. > > Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> > --- > kernel/irq/manage.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c > index a4afe5c..24e5eef 100644 > --- a/kernel/irq/manage.c > +++ b/kernel/irq/manage.c > @@ -1212,8 +1212,13 @@ __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 old_msk = old->flags & IRQF_TRIGGER_MASK; > + > + if (!old_msk) > + old_msk = irqd_get_trigger_type(&desc->irq_data); > + > if (!((old->flags & new->flags) & IRQF_SHARED) || > - ((old->flags ^ new->flags) & IRQF_TRIGGER_MASK) || > + ((old_msk ^ new->flags) & IRQF_TRIGGER_MASK) || > ((old->flags ^ new->flags) & IRQF_ONESHOT)) > goto mismatch; > > I'm afraid you're just papering over the issue here, as you leave the "old" descriptor in an inconsistent state w.r.t. the "new" descriptor. My view is that the old irq_desc should be "upgraded" to the new trigger configuration, because they are sharing a line and must have compatible behaviours. NONE is effectively a wildcard, and the second interrupt request should turn this wildcard into the real thing. The opposite case also exists (request a LEVEL interrupt first, then a NONE), and should be resolved the same way (NONE becomes LEVEL). Thoughts? M. -- Jazz is not dead. It just smells funny... -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
