On 17/03/16 14:19, Jon Hunter wrote: > Some IRQ chips, such as GPIO controllers or secondary level interrupt > controllers, may require require additional runtime power management > control to ensure they are accessible. For such IRQ chips, it makes sense > to enable the IRQ chip when interrupts are requested and disabled them > again once all interrupts have been freed. > > When mapping an IRQ, the IRQ type settings are read and then programmed. > The mapping of the IRQ happens before the IRQ is requested and so the > programming of the type settings occurs before the IRQ is requested. This > is a problem for IRQ chips that require additional power management > control because they may not be accessible yet. Therefore, when mapping > the IRQ, don't program the type settings, just save them and then program > these saved settings when the IRQ is requested (so long as if they are not > overridden via the call to request the IRQ). > > Add a stub function for irq_domain_free_irqs() to avoid any compilation > errors when CONFIG_IRQ_DOMAIN_HIERARCHY is not selected. > > Signed-off-by: Jon Hunter <[email protected]> > --- > include/linux/irqdomain.h | 3 +++ > kernel/irq/irqdomain.c | 18 ++++++++++++++---- > kernel/irq/manage.c | 7 +++++++ > 3 files changed, 24 insertions(+), 4 deletions(-) > > diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h > index 2aed04396210..fc66876d1965 100644 > --- a/include/linux/irqdomain.h > +++ b/include/linux/irqdomain.h > @@ -440,6 +440,9 @@ static inline int irq_domain_alloc_irqs(struct irq_domain > *domain, > return -1; > } > > +static inline void irq_domain_free_irqs(unsigned int virq, > + unsigned int nr_irqs) { } > + > static inline bool irq_domain_is_hierarchy(struct irq_domain *domain) > { > return false; > diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c > index 0ea285baa619..332bee2205e0 100644 > --- a/kernel/irq/irqdomain.c > +++ b/kernel/irq/irqdomain.c > @@ -576,6 +576,7 @@ static void of_phandle_args_to_fwspec(struct > of_phandle_args *irq_data, > unsigned int irq_create_fwspec_mapping(struct irq_fwspec *fwspec) > { > struct irq_domain *domain; > + struct irq_data *irq_data; > irq_hw_number_t hwirq; > unsigned int cur_type = IRQ_TYPE_NONE; > unsigned int type = IRQ_TYPE_NONE; > @@ -638,10 +639,19 @@ unsigned int irq_create_fwspec_mapping(struct > irq_fwspec *fwspec) > return 0; > } > > - /* Set type if specified and different than the current one */ > - if (type != IRQ_TYPE_NONE && > - type != irq_get_trigger_type(virq)) > - irq_set_irq_type(virq, type); > + irq_data = irq_get_irq_data(virq); > + if (!irq_data) { > + if (irq_domain_is_hierarchy(domain)) > + irq_domain_free_irqs(virq, 1); > + else > + irq_dispose_mapping(virq); > + > + return 0; > + }
I should only free/dispose here if we actually created it! Will fix this as well :-( Jon
