.BI "int l4_irq_control (unsigned int " "req" ", unsigned int " "flags" ", l4id_t " "id");
12
.SH DESCRIPTION
13
.B l4_irq_control()
14
enables a thread to register/unregister device irqs. Caller of this sytem call has an option to choose between synchronous or asynchronous irq handling.
15
.TP
16
.fi
17
.I req
18
denotes the type of operation to be performed.
19
20
.TP
21
.BR IRQ_CONTROL_REGISTER
22
Register the caller thread as irq handler for the irq index
23
.BR "id".
24
25
.TP
26
.BR IRQ_CONTROL_RELEASE
27
Unregister the caller thread, earlier registered as irq handler for the irq index
28
.BR "id".
29
30
.TP
31
.BR IRQ_CONTROL_WAIT
32
Wait for irq to happen. This flag is used by the irq handler to block and wait for irq to happen.
33
34
.TP
35
.fi
36
.I flags
37
denotes the slot number representing the irq handler, this is the identifier which distinguishes various handlers registered for the same device.
38
39
.TP
40
.fi
41
.I id
42
denotes the platform specific irq index of the concerned device.
43
44
.SH RETURN VALUE
45
.IR "l4_irq_control"()
46
Returns 0 on success, and negative value on failure. See below for error codes.
47
48
.SH ERRORS
49
.TP
50
.B -EINVAL
51
when the
52
.IR "flags"
53
passed is not having valid information.
54
55
.TP
56
.B -ENOUTCB
57
in case the thread making the system call does not have a valid utcb.
58
59
.TP
60
.B -EFAULT
61
in case utcb of caller thread is not mapped.
62
63
.TP
64
.B -ENOIRQ
65
in case the device represented by irq index
66
.BR "id"
67
is invalid or kernel does not allow user space tasks to avail this device.
