Commit 67196fea authored by Andy Shevchenko's avatar Andy Shevchenko Committed by Bartosz Golaszewski
Browse files

irqdomain: Introduce irq_domain_create_simple() API 



Linus Walleij pointed out that ird_domain_add_simple() gained
additional functionality and can't be anymore replaced with
a simple conditional. In preparation to upgrade GPIO library
to use fwnode, introduce irq_domain_create_simple() API which is
functional equivalent to the existing irq_domain_add_simple(),
but takes a pointer to the struct fwnode_handle as a parameter.

While at it, amend documentation to mention irq_domain_create_*()
functions where it makes sense.

Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: default avatarMarc Zyngier <maz@kernel.org>
Signed-off-by: default avatarBartosz Golaszewski <bgolaszewski@baylibre.com>
parent 3fd19d4b

Documentation/core-api/irq/irq-domain.rst

+12 −10
Original line number Diff line number Diff line
@@ -42,10 +42,10 @@ irq_domain usage 
================



An interrupt controller driver creates and registers an irq_domain by

calling one of the irq_domain_add_*() functions (each mapping method

has a different allocator function, more on that later).  The function

will return a pointer to the irq_domain on success.  The caller must

provide the allocator function with an irq_domain_ops structure.

calling one of the irq_domain_add_*() or irq_domain_create_*() functions

(each mapping method has a different allocator function, more on that later).

The function will return a pointer to the irq_domain on success. The caller

must provide the allocator function with an irq_domain_ops structure.



In most cases, the irq_domain will begin empty without any mappings

between hwirq and IRQ numbers.  Mappings are added to the irq_domain
@@ -147,6 +147,7 @@ Legacy 
	irq_domain_add_simple()

	irq_domain_add_legacy()

	irq_domain_add_legacy_isa()

	irq_domain_create_simple()

	irq_domain_create_legacy()



The Legacy mapping is a special case for drivers that already have a
@@ -169,13 +170,13 @@ supported. For example, ISA controllers would use the legacy map for 
mapping Linux IRQs 0-15 so that existing ISA drivers get the correct IRQ

numbers.



Most users of legacy mappings should use irq_domain_add_simple() which

will use a legacy domain only if an IRQ range is supplied by the

system and will otherwise use a linear domain mapping. The semantics

of this call are such that if an IRQ range is specified then

Most users of legacy mappings should use irq_domain_add_simple() or

irq_domain_create_simple() which will use a legacy domain only if an IRQ range

is supplied by the system and will otherwise use a linear domain mapping.

The semantics of this call are such that if an IRQ range is specified then

descriptors will be allocated on-the-fly for it, and if no range is

specified it will fall through to irq_domain_add_linear() which means

*no* irq descriptors will be allocated.

specified it will fall through to irq_domain_add_linear() or

irq_domain_create_linear() which means *no* irq descriptors will be allocated.



A typical use case for simple domains is where an irqchip provider

is supporting both dynamic and static IRQ assignments.
@@ -186,6 +187,7 @@ that the driver using the simple domain call irq_create_mapping() 
before any irq_find_mapping() since the latter will actually work

for the static IRQ assignment case.



irq_domain_add_simple() and irq_domain_create_simple() as well as

irq_domain_add_legacy() and irq_domain_create_legacy() are functionally

equivalent, except for the first argument is different - the former

accepts an Open Firmware specific 'struct device_node', while the latter

include/linux/irqdomain.h

+14 −5
Original line number Diff line number Diff line
@@ -256,7 +256,7 @@ struct irq_domain *__irq_domain_add(struct fwnode_handle *fwnode, int size, 
				    irq_hw_number_t hwirq_max, int direct_max,

				    const struct irq_domain_ops *ops,

				    void *host_data);

struct irq_domain *irq_domain_add_simple(struct device_node *of_node,

struct irq_domain *irq_domain_create_simple(struct fwnode_handle *fwnode,

					    unsigned int size,

					    unsigned int first_irq,

					    const struct irq_domain_ops *ops,
@@ -325,6 +325,15 @@ static inline struct irq_domain *irq_find_host(struct device_node *node) 
	return d;

}



static inline struct irq_domain *irq_domain_add_simple(struct device_node *of_node,

						       unsigned int size,

						       unsigned int first_irq,

						       const struct irq_domain_ops *ops,

						       void *host_data)

{

	return irq_domain_create_simple(of_node_to_fwnode(of_node), size, first_irq, ops, host_data);

}



/**

 * irq_domain_add_linear() - Allocate and register a linear revmap irq_domain.

 * @of_node: pointer to interrupt controller's device tree node.

kernel/irq/irqdomain.c

+10 −10
Original line number Diff line number Diff line
@@ -295,8 +295,8 @@ void irq_domain_update_bus_token(struct irq_domain *domain, 
EXPORT_SYMBOL_GPL(irq_domain_update_bus_token);



/**

 * irq_domain_add_simple() - Register an irq_domain and optionally map a range of irqs

 * @of_node: pointer to interrupt controller's device tree node.

 * irq_domain_create_simple() - Register an irq_domain and optionally map a range of irqs

 * @fwnode: firmware node for the interrupt controller

 * @size: total number of irqs in mapping

 * @first_irq: first number of irq block assigned to the domain,

 *	pass zero to assign irqs on-the-fly. If first_irq is non-zero, then
@@ -312,7 +312,7 @@ EXPORT_SYMBOL_GPL(irq_domain_update_bus_token); 
 * irqs get mapped dynamically on the fly. However, if the controller requires

 * static virq assignments (non-DT boot) then it will set that up correctly.

 */

struct irq_domain *irq_domain_add_simple(struct device_node *of_node,

struct irq_domain *irq_domain_create_simple(struct fwnode_handle *fwnode,

					    unsigned int size,

					    unsigned int first_irq,

					    const struct irq_domain_ops *ops,
@@ -320,7 +320,7 @@ struct irq_domain *irq_domain_add_simple(struct device_node *of_node, 
{

	struct irq_domain *domain;



	domain = __irq_domain_add(of_node_to_fwnode(of_node), size, size, 0, ops, host_data);

	domain = __irq_domain_add(fwnode, size, size, 0, ops, host_data);

	if (!domain)

		return NULL;
@@ -328,7 +328,7 @@ struct irq_domain *irq_domain_add_simple(struct device_node *of_node, 
		if (IS_ENABLED(CONFIG_SPARSE_IRQ)) {

			/* attempt to allocated irq_descs */

			int rc = irq_alloc_descs(first_irq, first_irq, size,

						 of_node_to_nid(of_node));

						 of_node_to_nid(to_of_node(fwnode)));

			if (rc < 0)

				pr_info("Cannot allocate irq_descs @ IRQ%d, assuming pre-allocated\n",

					first_irq);
@@ -338,7 +338,7 @@ struct irq_domain *irq_domain_add_simple(struct device_node *of_node, 


	return domain;

}

EXPORT_SYMBOL_GPL(irq_domain_add_simple);

EXPORT_SYMBOL_GPL(irq_domain_create_simple);



/**

 * irq_domain_add_legacy() - Allocate and register a legacy revmap irq_domain.