xref: /openbmc/linux/kernel/irq/devres.c (revision cfbb9be8)
1 #include <linux/module.h>
2 #include <linux/interrupt.h>
3 #include <linux/device.h>
4 #include <linux/gfp.h>
5 #include <linux/irq.h>
6 
7 #include "internals.h"
8 
9 /*
10  * Device resource management aware IRQ request/free implementation.
11  */
12 struct irq_devres {
13 	unsigned int irq;
14 	void *dev_id;
15 };
16 
17 static void devm_irq_release(struct device *dev, void *res)
18 {
19 	struct irq_devres *this = res;
20 
21 	free_irq(this->irq, this->dev_id);
22 }
23 
24 static int devm_irq_match(struct device *dev, void *res, void *data)
25 {
26 	struct irq_devres *this = res, *match = data;
27 
28 	return this->irq == match->irq && this->dev_id == match->dev_id;
29 }
30 
31 /**
32  *	devm_request_threaded_irq - allocate an interrupt line for a managed device
33  *	@dev: device to request interrupt for
34  *	@irq: Interrupt line to allocate
35  *	@handler: Function to be called when the IRQ occurs
36  *	@thread_fn: function to be called in a threaded interrupt context. NULL
37  *		    for devices which handle everything in @handler
38  *	@irqflags: Interrupt type flags
39  *	@devname: An ascii name for the claiming device, dev_name(dev) if NULL
40  *	@dev_id: A cookie passed back to the handler function
41  *
42  *	Except for the extra @dev argument, this function takes the
43  *	same arguments and performs the same function as
44  *	request_threaded_irq().  IRQs requested with this function will be
45  *	automatically freed on driver detach.
46  *
47  *	If an IRQ allocated with this function needs to be freed
48  *	separately, devm_free_irq() must be used.
49  */
50 int devm_request_threaded_irq(struct device *dev, unsigned int irq,
51 			      irq_handler_t handler, irq_handler_t thread_fn,
52 			      unsigned long irqflags, const char *devname,
53 			      void *dev_id)
54 {
55 	struct irq_devres *dr;
56 	int rc;
57 
58 	dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
59 			  GFP_KERNEL);
60 	if (!dr)
61 		return -ENOMEM;
62 
63 	if (!devname)
64 		devname = dev_name(dev);
65 
66 	rc = request_threaded_irq(irq, handler, thread_fn, irqflags, devname,
67 				  dev_id);
68 	if (rc) {
69 		devres_free(dr);
70 		return rc;
71 	}
72 
73 	dr->irq = irq;
74 	dr->dev_id = dev_id;
75 	devres_add(dev, dr);
76 
77 	return 0;
78 }
79 EXPORT_SYMBOL(devm_request_threaded_irq);
80 
81 /**
82  *	devm_request_any_context_irq - allocate an interrupt line for a managed device
83  *	@dev: device to request interrupt for
84  *	@irq: Interrupt line to allocate
85  *	@handler: Function to be called when the IRQ occurs
86  *	@thread_fn: function to be called in a threaded interrupt context. NULL
87  *		    for devices which handle everything in @handler
88  *	@irqflags: Interrupt type flags
89  *	@devname: An ascii name for the claiming device, dev_name(dev) if NULL
90  *	@dev_id: A cookie passed back to the handler function
91  *
92  *	Except for the extra @dev argument, this function takes the
93  *	same arguments and performs the same function as
94  *	request_any_context_irq().  IRQs requested with this function will be
95  *	automatically freed on driver detach.
96  *
97  *	If an IRQ allocated with this function needs to be freed
98  *	separately, devm_free_irq() must be used.
99  */
100 int devm_request_any_context_irq(struct device *dev, unsigned int irq,
101 			      irq_handler_t handler, unsigned long irqflags,
102 			      const char *devname, void *dev_id)
103 {
104 	struct irq_devres *dr;
105 	int rc;
106 
107 	dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
108 			  GFP_KERNEL);
109 	if (!dr)
110 		return -ENOMEM;
111 
112 	if (!devname)
113 		devname = dev_name(dev);
114 
115 	rc = request_any_context_irq(irq, handler, irqflags, devname, dev_id);
116 	if (rc < 0) {
117 		devres_free(dr);
118 		return rc;
119 	}
120 
121 	dr->irq = irq;
122 	dr->dev_id = dev_id;
123 	devres_add(dev, dr);
124 
125 	return rc;
126 }
127 EXPORT_SYMBOL(devm_request_any_context_irq);
128 
129 /**
130  *	devm_free_irq - free an interrupt
131  *	@dev: device to free interrupt for
132  *	@irq: Interrupt line to free
133  *	@dev_id: Device identity to free
134  *
135  *	Except for the extra @dev argument, this function takes the
136  *	same arguments and performs the same function as free_irq().
137  *	This function instead of free_irq() should be used to manually
138  *	free IRQs allocated with devm_request_irq().
139  */
140 void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id)
141 {
142 	struct irq_devres match_data = { irq, dev_id };
143 
144 	WARN_ON(devres_destroy(dev, devm_irq_release, devm_irq_match,
145 			       &match_data));
146 	free_irq(irq, dev_id);
147 }
148 EXPORT_SYMBOL(devm_free_irq);
149 
150 struct irq_desc_devres {
151 	unsigned int from;
152 	unsigned int cnt;
153 };
154 
155 static void devm_irq_desc_release(struct device *dev, void *res)
156 {
157 	struct irq_desc_devres *this = res;
158 
159 	irq_free_descs(this->from, this->cnt);
160 }
161 
162 /**
163  * __devm_irq_alloc_descs - Allocate and initialize a range of irq descriptors
164  *			    for a managed device
165  * @dev:	Device to allocate the descriptors for
166  * @irq:	Allocate for specific irq number if irq >= 0
167  * @from:	Start the search from this irq number
168  * @cnt:	Number of consecutive irqs to allocate
169  * @node:	Preferred node on which the irq descriptor should be allocated
170  * @owner:	Owning module (can be NULL)
171  * @affinity:	Optional pointer to an affinity mask array of size @cnt
172  *		which hints where the irq descriptors should be allocated
173  *		and which default affinities to use
174  *
175  * Returns the first irq number or error code.
176  *
177  * Note: Use the provided wrappers (devm_irq_alloc_desc*) for simplicity.
178  */
179 int __devm_irq_alloc_descs(struct device *dev, int irq, unsigned int from,
180 			   unsigned int cnt, int node, struct module *owner,
181 			   const struct cpumask *affinity)
182 {
183 	struct irq_desc_devres *dr;
184 	int base;
185 
186 	dr = devres_alloc(devm_irq_desc_release, sizeof(*dr), GFP_KERNEL);
187 	if (!dr)
188 		return -ENOMEM;
189 
190 	base = __irq_alloc_descs(irq, from, cnt, node, owner, affinity);
191 	if (base < 0) {
192 		devres_free(dr);
193 		return base;
194 	}
195 
196 	dr->from = base;
197 	dr->cnt = cnt;
198 	devres_add(dev, dr);
199 
200 	return base;
201 }
202 EXPORT_SYMBOL_GPL(__devm_irq_alloc_descs);
203 
204 #ifdef CONFIG_GENERIC_IRQ_CHIP
205 /**
206  * devm_irq_alloc_generic_chip - Allocate and initialize a generic chip
207  *                               for a managed device
208  * @dev:	Device to allocate the generic chip for
209  * @name:	Name of the irq chip
210  * @num_ct:	Number of irq_chip_type instances associated with this
211  * @irq_base:	Interrupt base nr for this chip
212  * @reg_base:	Register base address (virtual)
213  * @handler:	Default flow handler associated with this chip
214  *
215  * Returns an initialized irq_chip_generic structure. The chip defaults
216  * to the primary (index 0) irq_chip_type and @handler
217  */
218 struct irq_chip_generic *
219 devm_irq_alloc_generic_chip(struct device *dev, const char *name, int num_ct,
220 			    unsigned int irq_base, void __iomem *reg_base,
221 			    irq_flow_handler_t handler)
222 {
223 	struct irq_chip_generic *gc;
224 	unsigned long sz = sizeof(*gc) + num_ct * sizeof(struct irq_chip_type);
225 
226 	gc = devm_kzalloc(dev, sz, GFP_KERNEL);
227 	if (gc)
228 		irq_init_generic_chip(gc, name, num_ct,
229 				      irq_base, reg_base, handler);
230 
231 	return gc;
232 }
233 EXPORT_SYMBOL_GPL(devm_irq_alloc_generic_chip);
234 
235 struct irq_generic_chip_devres {
236 	struct irq_chip_generic *gc;
237 	u32 msk;
238 	unsigned int clr;
239 	unsigned int set;
240 };
241 
242 static void devm_irq_remove_generic_chip(struct device *dev, void *res)
243 {
244 	struct irq_generic_chip_devres *this = res;
245 
246 	irq_remove_generic_chip(this->gc, this->msk, this->clr, this->set);
247 }
248 
249 /**
250  * devm_irq_setup_generic_chip - Setup a range of interrupts with a generic
251  *                               chip for a managed device
252  *
253  * @dev:	Device to setup the generic chip for
254  * @gc:		Generic irq chip holding all data
255  * @msk:	Bitmask holding the irqs to initialize relative to gc->irq_base
256  * @flags:	Flags for initialization
257  * @clr:	IRQ_* bits to clear
258  * @set:	IRQ_* bits to set
259  *
260  * Set up max. 32 interrupts starting from gc->irq_base. Note, this
261  * initializes all interrupts to the primary irq_chip_type and its
262  * associated handler.
263  */
264 int devm_irq_setup_generic_chip(struct device *dev, struct irq_chip_generic *gc,
265 				u32 msk, enum irq_gc_flags flags,
266 				unsigned int clr, unsigned int set)
267 {
268 	struct irq_generic_chip_devres *dr;
269 
270 	dr = devres_alloc(devm_irq_remove_generic_chip,
271 			  sizeof(*dr), GFP_KERNEL);
272 	if (!dr)
273 		return -ENOMEM;
274 
275 	irq_setup_generic_chip(gc, msk, flags, clr, set);
276 
277 	dr->gc = gc;
278 	dr->msk = msk;
279 	dr->clr = clr;
280 	dr->set = set;
281 	devres_add(dev, dr);
282 
283 	return 0;
284 }
285 EXPORT_SYMBOL_GPL(devm_irq_setup_generic_chip);
286 #endif /* CONFIG_GENERIC_IRQ_CHIP */
287