projects/linux·blob v4.8 · refs

139 lines · 4.0 KiB

1#include <linux/module.h>
2#include <linux/interrupt.h>
3#include <linux/device.h>
4#include <linux/gfp.h>
5
6/*
7 * Device resource management aware IRQ request/free implementation.
8 */
9struct irq_devres {
10 unsigned int irq;
11 void *dev_id;
12};
13
14static void devm_irq_release(struct device *dev, void *res)
15{
16 struct irq_devres *this = res;
17
18 free_irq(this->irq, this->dev_id);
19}
20
21static int devm_irq_match(struct device *dev, void *res, void *data)
22{
23 struct irq_devres *this = res, *match = data;
24
25 return this->irq == match->irq && this->dev_id == match->dev_id;
26}
27
28/**
29 * devm_request_threaded_irq - allocate an interrupt line for a managed device
30 * @dev: device to request interrupt for
31 * @irq: Interrupt line to allocate
32 * @handler: Function to be called when the IRQ occurs
33 * @thread_fn: function to be called in a threaded interrupt context. NULL
34 * for devices which handle everything in @handler
35 * @irqflags: Interrupt type flags
36 * @devname: An ascii name for the claiming device
37 * @dev_id: A cookie passed back to the handler function
38 *
39 * Except for the extra @dev argument, this function takes the
40 * same arguments and performs the same function as
41 * request_threaded_irq(). IRQs requested with this function will be
42 * automatically freed on driver detach.
43 *
44 * If an IRQ allocated with this function needs to be freed
45 * separately, devm_free_irq() must be used.
46 */
47int devm_request_threaded_irq(struct device *dev, unsigned int irq,
48 irq_handler_t handler, irq_handler_t thread_fn,
49 unsigned long irqflags, const char *devname,
50 void *dev_id)
51{
52 struct irq_devres *dr;
53 int rc;
54
55 dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
56 GFP_KERNEL);
57 if (!dr)
58 return -ENOMEM;
59
60 rc = request_threaded_irq(irq, handler, thread_fn, irqflags, devname,
61 dev_id);
62 if (rc) {
63 devres_free(dr);
64 return rc;
65 }
66
67 dr->irq = irq;
68 dr->dev_id = dev_id;
69 devres_add(dev, dr);
70
71 return 0;
72}
73EXPORT_SYMBOL(devm_request_threaded_irq);
74
75/**
76 * devm_request_any_context_irq - allocate an interrupt line for a managed device
77 * @dev: device to request interrupt for
78 * @irq: Interrupt line to allocate
79 * @handler: Function to be called when the IRQ occurs
80 * @thread_fn: function to be called in a threaded interrupt context. NULL
81 * for devices which handle everything in @handler
82 * @irqflags: Interrupt type flags
83 * @devname: An ascii name for the claiming device
84 * @dev_id: A cookie passed back to the handler function
85 *
86 * Except for the extra @dev argument, this function takes the
87 * same arguments and performs the same function as
88 * request_any_context_irq(). IRQs requested with this function will be
89 * automatically freed on driver detach.
90 *
91 * If an IRQ allocated with this function needs to be freed
92 * separately, devm_free_irq() must be used.
93 */
94int devm_request_any_context_irq(struct device *dev, unsigned int irq,
95 irq_handler_t handler, unsigned long irqflags,
96 const char *devname, void *dev_id)
97{
98 struct irq_devres *dr;
99 int rc;
100
101 dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
102 GFP_KERNEL);
103 if (!dr)
104 return -ENOMEM;
105
106 rc = request_any_context_irq(irq, handler, irqflags, devname, dev_id);
107 if (rc < 0) {
108 devres_free(dr);
109 return rc;
110 }
111
112 dr->irq = irq;
113 dr->dev_id = dev_id;
114 devres_add(dev, dr);
115
116 return rc;
117}
118EXPORT_SYMBOL(devm_request_any_context_irq);
119
120/**
121 * devm_free_irq - free an interrupt
122 * @dev: device to free interrupt for
123 * @irq: Interrupt line to free
124 * @dev_id: Device identity to free
125 *
126 * Except for the extra @dev argument, this function takes the
127 * same arguments and performs the same function as free_irq().
128 * This function instead of free_irq() should be used to manually
129 * free IRQs allocated with devm_request_irq().
130 */
131void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id)
132{
133 struct irq_devres match_data = { irq, dev_id };
134
135 WARN_ON(devres_destroy(dev, devm_irq_release, devm_irq_match,
136 &match_data));
137 free_irq(irq, dev_id);
138}
139EXPORT_SYMBOL(devm_free_irq);