xref: /openbmc/linux/kernel/irq/devres.c (revision 1cac4f26)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/module.h>
3 #include <linux/interrupt.h>
4 #include <linux/device.h>
5 #include <linux/gfp.h>
6 #include <linux/irq.h>
7 
8 #include "internals.h"
9 
10 /*
11  * Device resource management aware IRQ request/free implementation.
12  */
13 struct irq_devres {
14 	unsigned int irq;
15 	void *dev_id;
16 };
17 
18 static void devm_irq_release(struct device *dev, void *res)
19 {
20 	struct irq_devres *this = res;
21 
22 	free_irq(this->irq, this->dev_id);
23 }
24 
25 static int devm_irq_match(struct device *dev, void *res, void *data)
26 {
27 	struct irq_devres *this = res, *match = data;
28 
29 	return this->irq == match->irq && this->dev_id == match->dev_id;
30 }
31 
32 /**
33  *	devm_request_threaded_irq - allocate an interrupt line for a managed device
34  *	@dev: device to request interrupt for
35  *	@irq: Interrupt line to allocate
36  *	@handler: Function to be called when the IRQ occurs
37  *	@thread_fn: function to be called in a threaded interrupt context. NULL
38  *		    for devices which handle everything in @handler
39  *	@irqflags: Interrupt type flags
40  *	@devname: An ascii name for the claiming device, dev_name(dev) if NULL
41  *	@dev_id: A cookie passed back to the handler function
42  *
43  *	Except for the extra @dev argument, this function takes the
44  *	same arguments and performs the same function as
45  *	request_threaded_irq().  IRQs requested with this function will be
46  *	automatically freed on driver detach.
47  *
48  *	If an IRQ allocated with this function needs to be freed
49  *	separately, devm_free_irq() must be used.
50  */
51 int devm_request_threaded_irq(struct device *dev, unsigned int irq,
52 			      irq_handler_t handler, irq_handler_t thread_fn,
53 			      unsigned long irqflags, const char *devname,
54 			      void *dev_id)
55 {
56 	struct irq_devres *dr;
57 	int rc;
58 
59 	dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
60 			  GFP_KERNEL);
61 	if (!dr)
62 		return -ENOMEM;
63 
64 	if (!devname)
65 		devname = dev_name(dev);
66 
67 	rc = request_threaded_irq(irq, handler, thread_fn, irqflags, devname,
68 				  dev_id);
69 	if (rc) {
70 		devres_free(dr);
71 		return rc;
72 	}
73 
74 	dr->irq = irq;
75 	dr->dev_id = dev_id;
76 	devres_add(dev, dr);
77 
78 	return 0;
79 }
80 EXPORT_SYMBOL(devm_request_threaded_irq);
81 
82 /**
83  *	devm_request_any_context_irq - allocate an interrupt line for a managed device
84  *	@dev: device to request interrupt for
85  *	@irq: Interrupt line to allocate
86  *	@handler: Function to be called when the IRQ occurs
87  *	@thread_fn: function to be called in a threaded interrupt context. NULL
88  *		    for devices which handle everything in @handler
89  *	@irqflags: Interrupt type flags
90  *	@devname: An ascii name for the claiming device, dev_name(dev) if NULL
91  *	@dev_id: A cookie passed back to the handler function
92  *
93  *	Except for the extra @dev argument, this function takes the
94  *	same arguments and performs the same function as
95  *	request_any_context_irq().  IRQs requested with this function will be
96  *	automatically freed on driver detach.
97  *
98  *	If an IRQ allocated with this function needs to be freed
99  *	separately, devm_free_irq() must be used.
100  */
101 int devm_request_any_context_irq(struct device *dev, unsigned int irq,
102 			      irq_handler_t handler, unsigned long irqflags,
103 			      const char *devname, void *dev_id)
104 {
105 	struct irq_devres *dr;
106 	int rc;
107 
108 	dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
109 			  GFP_KERNEL);
110 	if (!dr)
111 		return -ENOMEM;
112 
113 	if (!devname)
114 		devname = dev_name(dev);
115 
116 	rc = request_any_context_irq(irq, handler, irqflags, devname, dev_id);
117 	if (rc < 0) {
118 		devres_free(dr);
119 		return rc;
120 	}
121 
122 	dr->irq = irq;
123 	dr->dev_id = dev_id;
124 	devres_add(dev, dr);
125 
126 	return rc;
127 }
128 EXPORT_SYMBOL(devm_request_any_context_irq);
129 
130 /**
131  *	devm_free_irq - free an interrupt
132  *	@dev: device to free interrupt for
133  *	@irq: Interrupt line to free
134  *	@dev_id: Device identity to free
135  *
136  *	Except for the extra @dev argument, this function takes the
137  *	same arguments and performs the same function as free_irq().
138  *	This function instead of free_irq() should be used to manually
139  *	free IRQs allocated with devm_request_irq().
140  */
141 void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id)
142 {
143 	struct irq_devres match_data = { irq, dev_id };
144 
145 	WARN_ON(devres_destroy(dev, devm_irq_release, devm_irq_match,
146 			       &match_data));
147 	free_irq(irq, dev_id);
148 }
149 EXPORT_SYMBOL(devm_free_irq);
150 
151 struct irq_desc_devres {
152 	unsigned int from;
153 	unsigned int cnt;
154 };
155 
156 static void devm_irq_desc_release(struct device *dev, void *res)
157 {
158 	struct irq_desc_devres *this = res;
159 
160 	irq_free_descs(this->from, this->cnt);
161 }
162 
163 /**
164  * __devm_irq_alloc_descs - Allocate and initialize a range of irq descriptors
165  *			    for a managed device
166  * @dev:	Device to allocate the descriptors for
167  * @irq:	Allocate for specific irq number if irq >= 0
168  * @from:	Start the search from this irq number
169  * @cnt:	Number of consecutive irqs to allocate
170  * @node:	Preferred node on which the irq descriptor should be allocated
171  * @owner:	Owning module (can be NULL)
172  * @affinity:	Optional pointer to an irq_affinity_desc array of size @cnt
173  *		which hints where the irq descriptors should be allocated
174  *		and which default affinities to use
175  *
176  * Returns the first irq number or error code.
177  *
178  * Note: Use the provided wrappers (devm_irq_alloc_desc*) for simplicity.
179  */
180 int __devm_irq_alloc_descs(struct device *dev, int irq, unsigned int from,
181 			   unsigned int cnt, int node, struct module *owner,
182 			   const struct irq_affinity_desc *affinity)
183 {
184 	struct irq_desc_devres *dr;
185 	int base;
186 
187 	dr = devres_alloc(devm_irq_desc_release, sizeof(*dr), GFP_KERNEL);
188 	if (!dr)
189 		return -ENOMEM;
190 
191 	base = __irq_alloc_descs(irq, from, cnt, node, owner, affinity);
192 	if (base < 0) {
193 		devres_free(dr);
194 		return base;
195 	}
196 
197 	dr->from = base;
198 	dr->cnt = cnt;
199 	devres_add(dev, dr);
200 
201 	return base;
202 }
203 EXPORT_SYMBOL_GPL(__devm_irq_alloc_descs);
204 
205 #ifdef CONFIG_GENERIC_IRQ_CHIP
206 /**
207  * devm_irq_alloc_generic_chip - Allocate and initialize a generic chip
208  *                               for a managed device
209  * @dev:	Device to allocate the generic chip for
210  * @name:	Name of the irq chip
211  * @num_ct:	Number of irq_chip_type instances associated with this
212  * @irq_base:	Interrupt base nr for this chip
213  * @reg_base:	Register base address (virtual)
214  * @handler:	Default flow handler associated with this chip
215  *
216  * Returns an initialized irq_chip_generic structure. The chip defaults
217  * to the primary (index 0) irq_chip_type and @handler
218  */
219 struct irq_chip_generic *
220 devm_irq_alloc_generic_chip(struct device *dev, const char *name, int num_ct,
221 			    unsigned int irq_base, void __iomem *reg_base,
222 			    irq_flow_handler_t handler)
223 {
224 	struct irq_chip_generic *gc;
225 	unsigned long sz = sizeof(*gc) + num_ct * sizeof(struct irq_chip_type);
226 
227 	gc = devm_kzalloc(dev, sz, GFP_KERNEL);
228 	if (gc)
229 		irq_init_generic_chip(gc, name, num_ct,
230 				      irq_base, reg_base, handler);
231 
232 	return gc;
233 }
234 EXPORT_SYMBOL_GPL(devm_irq_alloc_generic_chip);
235 
236 struct irq_generic_chip_devres {
237 	struct irq_chip_generic *gc;
238 	u32 msk;
239 	unsigned int clr;
240 	unsigned int set;
241 };
242 
243 static void devm_irq_remove_generic_chip(struct device *dev, void *res)
244 {
245 	struct irq_generic_chip_devres *this = res;
246 
247 	irq_remove_generic_chip(this->gc, this->msk, this->clr, this->set);
248 }
249 
250 /**
251  * devm_irq_setup_generic_chip - Setup a range of interrupts with a generic
252  *                               chip for a managed device
253  *
254  * @dev:	Device to setup the generic chip for
255  * @gc:		Generic irq chip holding all data
256  * @msk:	Bitmask holding the irqs to initialize relative to gc->irq_base
257  * @flags:	Flags for initialization
258  * @clr:	IRQ_* bits to clear
259  * @set:	IRQ_* bits to set
260  *
261  * Set up max. 32 interrupts starting from gc->irq_base. Note, this
262  * initializes all interrupts to the primary irq_chip_type and its
263  * associated handler.
264  */
265 int devm_irq_setup_generic_chip(struct device *dev, struct irq_chip_generic *gc,
266 				u32 msk, enum irq_gc_flags flags,
267 				unsigned int clr, unsigned int set)
268 {
269 	struct irq_generic_chip_devres *dr;
270 
271 	dr = devres_alloc(devm_irq_remove_generic_chip,
272 			  sizeof(*dr), GFP_KERNEL);
273 	if (!dr)
274 		return -ENOMEM;
275 
276 	irq_setup_generic_chip(gc, msk, flags, clr, set);
277 
278 	dr->gc = gc;
279 	dr->msk = msk;
280 	dr->clr = clr;
281 	dr->set = set;
282 	devres_add(dev, dr);
283 
284 	return 0;
285 }
286 EXPORT_SYMBOL_GPL(devm_irq_setup_generic_chip);
287 #endif /* CONFIG_GENERIC_IRQ_CHIP */
288