On 13/06/16 11:42, Marc Zyngier wrote: > On 07/06/16 16:12, Jon Hunter wrote: >> For some devices the IRQ trigger type for a device is read from >> firmware, such as device-tree. The IRQ trigger type is typically read >> when the mapping for IRQ is created, which is before the IRQ is >> requested. Hence, the IRQ trigger type is programmed when mapping the >> IRQ and not when requesting the IRQ. >> >> Although this works for most cases, in order to support IRQ chips which >> require runtime power management, which may not be accessible prior >> to requesting the IRQ, it is desirable to look-up the IRQ trigger type >> when it is requested. Therefore, if the IRQ trigger type is not >> specified when __setup_irq() is called, look-up the saved IRQ trigger >> type. This will allow us to defer the programming of the trigger type >> from when the IRQ is mapped to when it is actually requested. >> >> Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx> >> Reviewed-by: Marc Zyngier <marc.zyngier@xxxxxxx> >> --- >> kernel/irq/manage.c | 7 +++++++ >> 1 file changed, 7 insertions(+) >> >> diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c >> index ef0bc02c3a70..eaedeb74b49d 100644 >> --- a/kernel/irq/manage.c >> +++ b/kernel/irq/manage.c >> @@ -1117,6 +1117,13 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) >> new->irq = irq; >> >> /* >> + * If the trigger type is not specified by the caller, >> + * then use the default for this interrupt. >> + */ >> + if (!(new->flags & IRQF_TRIGGER_MASK)) >> + new->flags |= irqd_get_trigger_type(&desc->irq_data); >> + >> + /* >> * Check whether the interrupt nests into another interrupt >> * thread. >> */ >> > > I've added the following patch to the queue, in order to deal with > percpu interrupts that were not handled by this patch: > > diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c > index f8fd1fb..00cfc85 100644 > --- a/kernel/irq/manage.c > +++ b/kernel/irq/manage.c > @@ -1751,7 +1751,14 @@ void enable_percpu_irq(unsigned int irq, unsigned int type) > if (!desc) > return; > > + /* > + * If the trigger type is not specified by the caller, then > + * use the default for this interrupt. > + */ > type &= IRQ_TYPE_SENSE_MASK; > + if (type == IRQ_TYPE_NONE) > + type = irqd_get_trigger_type(&desc->irq_data); > + I am wondering if you need this here because now __setup_irq(), called by request_percpu_irq(), will actually look-up the saved type even for a percpu-irq. So shouldn't this already be handled? Or am I missing something? Cheers Jon -- nvpublic -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
