summaryrefslogtreecommitdiff
path: root/kernel/irq/devres.c
blob: 194c506d9d20097d5d94ba09bd7e00d50bc5e0c7 (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
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/gfp.h>
#include <linux/irq.h>

#include "internals.h"

/*
 * Device resource management aware IRQ request/free implementation.
 */
struct irq_devres {
	unsigned int irq;
	void *dev_id;
};

static void devm_irq_release(struct device *dev, void *res)
{
	struct irq_devres *this = res;

	free_irq(this->irq, this->dev_id);
}

static int devm_irq_match(struct device *dev, void *res, void *data)
{
	struct irq_devres *this = res, *match = data;

	return this->irq == match->irq && this->dev_id == match->dev_id;
}

/**
 *	devm_request_threaded_irq - allocate an interrupt line for a managed device
 *	@dev: device to request interrupt for
 *	@irq: Interrupt line to allocate
 *	@handler: Function to be called when the IRQ occurs
 *	@thread_fn: function to be called in a threaded interrupt context. NULL
 *		    for devices which handle everything in @handler
 *	@irqflags: Interrupt type flags
 *	@devname: An ascii name for the claiming device, dev_name(dev) if NULL
 *	@dev_id: A cookie passed back to the handler function
 *
 *	Except for the extra @dev argument, this function takes the
 *	same arguments and performs the same function as
 *	request_threaded_irq().  IRQs requested with this function will be
 *	automatically freed on driver detach.
 *
 *	If an IRQ allocated with this function needs to be freed
 *	separately, devm_free_irq() must be used.
 */
int devm_request_threaded_irq(struct device *dev, unsigned int irq,
			      irq_handler_t handler, irq_handler_t thread_fn,
			      unsigned long irqflags, const char *devname,
			      void *dev_id)
{
	struct irq_devres *dr;
	int rc;

	dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
			  GFP_KERNEL);
	if (!dr)
		return -ENOMEM;

	if (!devname)
		devname = dev_name(dev);

	rc = request_threaded_irq(irq, handler, thread_fn, irqflags, devname,
				  dev_id);
	if (rc) {
		devres_free(dr);
		return rc;
	}

	dr->irq = irq;
	dr->dev_id = dev_id;
	devres_add(dev, dr);

	return 0;
}
EXPORT_SYMBOL(devm_request_threaded_irq);

/**
 *	devm_request_any_context_irq - allocate an interrupt line for a managed device
 *	@dev: device to request interrupt for
 *	@irq: Interrupt line to allocate
 *	@handler: Function to be called when the IRQ occurs
 *	@thread_fn: function to be called in a threaded interrupt context. NULL
 *		    for devices which handle everything in @handler
 *	@irqflags: Interrupt type flags
 *	@devname: An ascii name for the claiming device, dev_name(dev) if NULL
 *	@dev_id: A cookie passed back to the handler function
 *
 *	Except for the extra @dev argument, this function takes the
 *	same arguments and performs the same function as
 *	request_any_context_irq().  IRQs requested with this function will be
 *	automatically freed on driver detach.
 *
 *	If an IRQ allocated with this function needs to be freed
 *	separately, devm_free_irq() must be used.
 */
int devm_request_any_context_irq(struct device *dev, unsigned int irq,
			      irq_handler_t handler, unsigned long irqflags,
			      const char *devname, void *dev_id)
{
	struct irq_devres *dr;
	int rc;

	dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
			  GFP_KERNEL);
	if (!dr)
		return -ENOMEM;

	if (!devname)
		devname = dev_name(dev);

	rc = request_any_context_irq(irq, handler, irqflags, devname, dev_id);
	if (rc < 0) {
		devres_free(dr);
		return rc;
	}

	dr->irq = irq;
	dr->dev_id = dev_id;
	devres_add(dev, dr);

	return rc;
}
EXPORT_SYMBOL(devm_request_any_context_irq);

/**
 *	devm_free_irq - free an interrupt
 *	@dev: device to free interrupt for
 *	@irq: Interrupt line to free
 *	@dev_id: Device identity to free
 *
 *	Except for the extra @dev argument, this function takes the
 *	same arguments and performs the same function as free_irq().
 *	This function instead of free_irq() should be used to manually
 *	free IRQs allocated with devm_request_irq().
 */
void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id)
{
	struct irq_devres match_data = { irq, dev_id };

	WARN_ON(devres_destroy(dev, devm_irq_release, devm_irq_match,
			       &match_data));
	free_irq(irq, dev_id);
}
EXPORT_SYMBOL(devm_free_irq);

struct irq_desc_devres {
	unsigned int from;
	unsigned int cnt;
};

static void devm_irq_desc_release(struct device *dev, void *res)
{
	struct irq_desc_devres *this = res;

	irq_free_descs(this->from, this->cnt);
}

/**
 * __devm_irq_alloc_descs - Allocate and initialize a range of irq descriptors
 *			    for a managed device
 * @dev:	Device to allocate the descriptors for
 * @irq:	Allocate for specific irq number if irq >= 0
 * @from:	Start the search from this irq number
 * @cnt:	Number of consecutive irqs to allocate
 * @node:	Preferred node on which the irq descriptor should be allocated
 * @owner:	Owning module (can be NULL)
 * @affinity:	Optional pointer to an affinity mask array of size @cnt
 *		which hints where the irq descriptors should be allocated
 *		and which default affinities to use
 *
 * Returns the first irq number or error code.
 *
 * Note: Use the provided wrappers (devm_irq_alloc_desc*) for simplicity.
 */
int __devm_irq_alloc_descs(struct device *dev, int irq, unsigned int from,
			   unsigned int cnt, int node, struct module *owner,
			   const struct cpumask *affinity)
{
	struct irq_desc_devres *dr;
	int base;

	dr = devres_alloc(devm_irq_desc_release, sizeof(*dr), GFP_KERNEL);
	if (!dr)
		return -ENOMEM;

	base = __irq_alloc_descs(irq, from, cnt, node, owner, affinity);
	if (base < 0) {
		devres_free(dr);
		return base;
	}

	dr->from = base;
	dr->cnt = cnt;
	devres_add(dev, dr);

	return base;
}
EXPORT_SYMBOL_GPL(__devm_irq_alloc_descs);

#ifdef CONFIG_GENERIC_IRQ_CHIP
/**
 * devm_irq_alloc_generic_chip - Allocate and initialize a generic chip
 *                               for a managed device
 * @dev:	Device to allocate the generic chip for
 * @name:	Name of the irq chip
 * @num_ct:	Number of irq_chip_type instances associated with this
 * @irq_base:	Interrupt base nr for this chip
 * @reg_base:	Register base address (virtual)
 * @handler:	Default flow handler associated with this chip
 *
 * Returns an initialized irq_chip_generic structure. The chip defaults
 * to the primary (index 0) irq_chip_type and @handler
 */
struct irq_chip_generic *
devm_irq_alloc_generic_chip(struct device *dev, const char *name, int num_ct,
			    unsigned int irq_base, void __iomem *reg_base,
			    irq_flow_handler_t handler)
{
	struct irq_chip_generic *gc;
	unsigned long sz = sizeof(*gc) + num_ct * sizeof(struct irq_chip_type);

	gc = devm_kzalloc(dev, sz, GFP_KERNEL);
	if (gc)
		irq_init_generic_chip(gc, name, num_ct,
				      irq_base, reg_base, handler);

	return gc;
}
EXPORT_SYMBOL_GPL(devm_irq_alloc_generic_chip);

struct irq_generic_chip_devres {
	struct irq_chip_generic *gc;
	u32 msk;
	unsigned int clr;
	unsigned int set;
};

static void devm_irq_remove_generic_chip(struct device *dev, void *res)
{
	struct irq_generic_chip_devres *this = res;

	irq_remove_generic_chip(this->gc, this->msk, this->clr, this->set);
}

/**
 * devm_irq_setup_generic_chip - Setup a range of interrupts with a generic
 *                               chip for a managed device
 *
 * @dev:	Device to setup the generic chip for
 * @gc:		Generic irq chip holding all data
 * @msk:	Bitmask holding the irqs to initialize relative to gc->irq_base
 * @flags:	Flags for initialization
 * @clr:	IRQ_* bits to clear
 * @set:	IRQ_* bits to set
 *
 * Set up max. 32 interrupts starting from gc->irq_base. Note, this
 * initializes all interrupts to the primary irq_chip_type and its
 * associated handler.
 */
int devm_irq_setup_generic_chip(struct device *dev, struct irq_chip_generic *gc,
				u32 msk, enum irq_gc_flags flags,
				unsigned int clr, unsigned int set)
{
	struct irq_generic_chip_devres *dr;

	dr = devres_alloc(devm_irq_remove_generic_chip,
			  sizeof(*dr), GFP_KERNEL);
	if (!dr)
		return -ENOMEM;

	irq_setup_generic_chip(gc, msk, flags, clr, set);

	dr->gc = gc;
	dr->msk = msk;
	dr->clr = clr;
	dr->set = set;
	devres_add(dev, dr);

	return 0;
}
EXPORT_SYMBOL_GPL(devm_irq_setup_generic_chip);
#endif /* CONFIG_GENERIC_IRQ_CHIP */