=========
The original implementation of interrupt handling in Linux uses the
-:c:func:`__do_IRQ` super-handler, which is able to deal with every type of
+__do_IRQ() super-handler, which is able to deal with every type of
interrupt logic.
Originally, Russell King identified different types of handlers to build
- Fast EOI type
-In the SMP world of the :c:func:`__do_IRQ` super-handler another type was
+In the SMP world of the __do_IRQ() super-handler another type was
identified:
- Per CPU type
(sub)architecture specific 'edge type' implementation.
To make the transition to the new model easier and prevent the breakage
-of existing implementations, the :c:func:`__do_IRQ` super-handler is still
+of existing implementations, the __do_IRQ() super-handler is still
available. This leads to a kind of duality for the time being. Over time
the new model should be used in more and more architectures, as it
enables smaller and cleaner IRQ subsystems. It's deprecated for three
interrupt chip structure which are assigned to this interrupt.
Whenever an interrupt triggers, the low-level architecture code calls
-into the generic interrupt code by calling :c:func:`desc->handle_irq`. This
+into the generic interrupt code by calling desc->handle_irq(). This
high-level IRQ handling function only uses desc->irq_data.chip
primitives referenced by the assigned chip descriptor structure.
The high-level Driver API consists of following functions:
-- :c:func:`request_irq`
+- request_irq()
-- :c:func:`free_irq`
+- free_irq()
-- :c:func:`disable_irq`
+- disable_irq()
-- :c:func:`enable_irq`
+- enable_irq()
-- :c:func:`disable_irq_nosync` (SMP only)
+- disable_irq_nosync() (SMP only)
-- :c:func:`synchronize_irq` (SMP only)
+- synchronize_irq() (SMP only)
-- :c:func:`irq_set_irq_type`
+- irq_set_irq_type()
-- :c:func:`irq_set_irq_wake`
+- irq_set_irq_wake()
-- :c:func:`irq_set_handler_data`
+- irq_set_handler_data()
-- :c:func:`irq_set_chip`
+- irq_set_chip()
-- :c:func:`irq_set_chip_data`
+- irq_set_chip_data()
See the autogenerated function documentation for details.
The generic layer provides a set of pre-defined irq-flow methods:
-- :c:func:`handle_level_irq`
+- handle_level_irq()
-- :c:func:`handle_edge_irq`
+- handle_edge_irq()
-- :c:func:`handle_fasteoi_irq`
+- handle_fasteoi_irq()
-- :c:func:`handle_simple_irq`
+- handle_simple_irq()
-- :c:func:`handle_percpu_irq`
+- handle_percpu_irq()
-- :c:func:`handle_edge_eoi_irq`
+- handle_edge_eoi_irq()
-- :c:func:`handle_bad_irq`
+- handle_bad_irq()
The interrupt flow handlers (either pre-defined or architecture
specific) are assigned to specific interrupts by the architecture either
This per interrupt selectable feature, which was introduced by Russell
King in the ARM interrupt implementation, does not mask an interrupt at
-the hardware level when :c:func:`disable_irq` is called. The interrupt is kept
+the hardware level when disable_irq() is called. The interrupt is kept
enabled and is masked in the flow handler when an interrupt event
happens. This prevents losing edge interrupts on hardware which does not
store an edge interrupt event while the interrupt is disabled at the
hardware level. When an interrupt arrives while the IRQ_DISABLED flag
is set, then the interrupt is masked at the hardware level and the
IRQ_PENDING bit is set. When the interrupt is re-enabled by
-:c:func:`enable_irq` the pending bit is checked and if it is set, the interrupt
+enable_irq() the pending bit is checked and if it is set, the interrupt
is resent either via hardware or by a software resend mechanism. (It's
necessary to enable CONFIG_HARDIRQS_SW_RESEND when you want to use
the delayed interrupt disable feature and your hardware is not capable
__do_IRQ entry point
====================
-The original implementation :c:func:`__do_IRQ` was an alternative entry point
+The original implementation __do_IRQ() was an alternative entry point
for all types of interrupts. It no longer exists.
This handler turned out to be not suitable for all interrupt hardware