On 20/04/16 12:03, 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 <jonath...@nvidia.com>
> ---
> include/linux/irqdomain.h | 3 +++
> kernel/irq/irqdomain.c | 17 +++++++++++++----
> 2 files changed, 16 insertions(+), 4 deletions(-)
[snip]
> - /* 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;
> + }
> +
> + /* Store trigger type */
> + irqd_set_trigger_type(irq_data, type);
> +
I appear to have missed another place for saving the irq type
which I had change in this version. Next time I will triple
check! Should have been ...
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 3d6ef5527b71..46ecf5d468b2 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -569,6 +569,7 @@ 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 type = IRQ_TYPE_NONE;
int virq;
@@ -619,7 +620,11 @@ unsigned int irq_create_fwspec_mapping(struct irq_fwspec
*fwspec)
* it now and return the interrupt number.
*/
if (IRQ_TYPE_NONE == irq_get_trigger_type(virq)) {
- irq_set_irq_type(virq, type);
+ irq_data = irq_get_irq_data(virq);
+ if (!irq_data)
+ return 0;
+
+ irqd_set_trigger_type(irq_data, type);
return virq;
}
@@ -639,10 +644,18 @@ unsigned int irq_create_fwspec_mapping(struct irq_fwspec
*fwspec)
return virq;
}
- /* 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;
+ }
+
+ /* Store trigger type */
+ irqd_set_trigger_type(irq_data, type);
+
return virq;
}
EXPORT_SYMBOL_GPL(irq_create_fwspec_mapping);
