summaryrefslogtreecommitdiffstats
path: root/kernel/irq/irqdomain.c
blob: d5828da3fd383908c142971a0b5a91c10be17f71 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/slab.h>

static LIST_HEAD(irq_domain_list);
static DEFINE_MUTEX(irq_domain_mutex);

/**
 * irq_domain_add() - Register an irq_domain
 * @domain: ptr to initialized irq_domain structure
 *
 * Registers an irq_domain structure.  The irq_domain must at a minimum be
 * initialized with an ops structure pointer, and either a ->to_irq hook or
 * a valid irq_base value.  Everything else is optional.
 */
void irq_domain_add(struct irq_domain *domain)
{
	struct irq_data *d;
	int hwirq;

	/*
	 * This assumes that the irq_domain owner has already allocated
	 * the irq_descs.  This block will be removed when support for dynamic
	 * allocation of irq_descs is added to irq_domain.
	 */
	for (hwirq = 0; hwirq < domain->nr_irq; hwirq++) {
		d = irq_get_irq_data(irq_domain_to_irq(domain, hwirq));
		if (d || d->domain) {
			/* things are broken; just report, don't clean up */
			WARN(1, "error: irq_desc already assigned to a domain");
			return;
		}
		d->domain = domain;
		d->hwirq = hwirq;
	}

	mutex_lock(&irq_domain_mutex);
	list_add(&domain->list, &irq_domain_list);
	mutex_unlock(&irq_domain_mutex);
}

/**
 * irq_domain_del() - Unregister an irq_domain
 * @domain: ptr to registered irq_domain.
 */
void irq_domain_del(struct irq_domain *domain)
{
	struct irq_data *d;
	int hwirq;

	mutex_lock(&irq_domain_mutex);
	list_del(&domain->list);
	mutex_unlock(&irq_domain_mutex);

	/* Clear the irq_domain assignments */
	for (hwirq = 0; hwirq < domain->nr_irq; hwirq++) {
		d = irq_get_irq_data(irq_domain_to_irq(domain, hwirq));
		d->domain = NULL;
	}
}

#if defined(CONFIG_OF_IRQ)
/**
 * irq_create_of_mapping() - Map a linux irq number from a DT interrupt spec
 *
 * Used by the device tree interrupt mapping code to translate a device tree
 * interrupt specifier to a valid linux irq number.  Returns either a valid
 * linux IRQ number or 0.
 *
 * When the caller no longer need the irq number returned by this function it
 * should arrange to call irq_dispose_mapping().
 */
unsigned int irq_create_of_mapping(struct device_node *controller,
				   const u32 *intspec, unsigned int intsize)
{
	struct irq_domain *domain;
	unsigned long hwirq;
	unsigned int irq, type;
	int rc = -EINVAL;

	/* Find a domain which can translate the irq spec */
	mutex_lock(&irq_domain_mutex);
	list_for_each_entry(domain, &irq_domain_list, list) {
		if (!domain->ops->dt_translate)
			continue;
		rc = domain->ops->dt_translate(domain, controller,
					intspec, intsize, &hwirq, &type);
		if (rc == 0)
			break;
	}
	mutex_unlock(&irq_domain_mutex);

	if (rc != 0)
		return 0;

	irq = irq_domain_to_irq(domain, hwirq);
	if (type != IRQ_TYPE_NONE)
		irq_set_irq_type(irq, type);
	pr_debug("%s: mapped hwirq=%i to irq=%i, flags=%x\n",
		 controller->full_name, (int)hwirq, irq, type);
	return irq;
}
EXPORT_SYMBOL_GPL(irq_create_of_mapping);

/**
 * irq_dispose_mapping() - Discard a mapping created by irq_create_of_mapping()
 * @irq: linux irq number to be discarded
 *
 * Calling this function indicates the caller no longer needs a reference to
 * the linux irq number returned by a prior call to irq_create_of_mapping().
 */
void irq_dispose_mapping(unsigned int irq)
{
	/*
	 * nothing yet; will be filled when support for dynamic allocation of
	 * irq_descs is added to irq_domain
	 */
}
EXPORT_SYMBOL_GPL(irq_dispose_mapping);

int irq_domain_simple_dt_translate(struct irq_domain *d,
			    struct device_node *controller,
			    const u32 *intspec, unsigned int intsize,
			    unsigned long *out_hwirq, unsigned int *out_type)
{
	if (d->of_node != controller)
		return -EINVAL;
	if (intsize < 1)
		return -EINVAL;

	*out_hwirq = intspec[0];
	*out_type = IRQ_TYPE_NONE;
	if (intsize > 1)
		*out_type = intspec[1] & IRQ_TYPE_SENSE_MASK;
	return 0;
}

struct irq_domain_ops irq_domain_simple_ops = {
	.dt_translate = irq_domain_simple_dt_translate,
};
EXPORT_SYMBOL_GPL(irq_domain_simple_ops);

/**
 * irq_domain_create_simple() - Set up a 'simple' translation range
 */
void irq_domain_add_simple(struct device_node *controller, int irq_base)
{
	struct irq_domain *domain;

	domain = kzalloc(sizeof(*domain), GFP_KERNEL);
	if (!domain) {
		WARN_ON(1);
		return;
	}

	domain->irq_base = irq_base;
	domain->of_node = of_node_get(controller);
	domain->ops = &irq_domain_simple_ops;
	irq_domain_add(domain);
}
EXPORT_SYMBOL_GPL(irq_domain_add_simple);

void irq_domain_generate_simple(const struct of_device_id *match,
				u64 phys_base, unsigned int irq_start)
{
	struct device_node *node;
	pr_info("looking for phys_base=%llx, irq_start=%i\n",
		(unsigned long long) phys_base, (int) irq_start);
	node = of_find_matching_node_by_address(NULL, match, phys_base);
	if (node)
		irq_domain_add_simple(node, irq_start);
	else
		pr_info("no node found\n");
}
EXPORT_SYMBOL_GPL(irq_domain_generate_simple);
#endif /* CONFIG_OF_IRQ */