xref: /openbmc/linux/kernel/irq/devres.c (revision 6c33a6f4)
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  *	@irqflags: Interrupt type flags
88  *	@devname: An ascii name for the claiming device, dev_name(dev) if NULL
89  *	@dev_id: A cookie passed back to the handler function
90  *
91  *	Except for the extra @dev argument, this function takes the
92  *	same arguments and performs the same function as
93  *	request_any_context_irq().  IRQs requested with this function will be
94  *	automatically freed on driver detach.
95  *
96  *	If an IRQ allocated with this function needs to be freed
97  *	separately, devm_free_irq() must be used.
98  */
99 int devm_request_any_context_irq(struct device *dev, unsigned int irq,
100 			      irq_handler_t handler, unsigned long irqflags,
101 			      const char *devname, void *dev_id)
102 {
103 	struct irq_devres *dr;
104 	int rc;
105 
106 	dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
107 			  GFP_KERNEL);
108 	if (!dr)
109 		return -ENOMEM;
110 
111 	if (!devname)
112 		devname = dev_name(dev);
113 
114 	rc = request_any_context_irq(irq, handler, irqflags, devname, dev_id);
115 	if (rc < 0) {
116 		devres_free(dr);
117 		return rc;
118 	}
119 
120 	dr->irq = irq;
121 	dr->dev_id = dev_id;
122 	devres_add(dev, dr);
123 
124 	return rc;
125 }
126 EXPORT_SYMBOL(devm_request_any_context_irq);
127 
128 /**
129  *	devm_free_irq - free an interrupt
130  *	@dev: device to free interrupt for
131  *	@irq: Interrupt line to free
132  *	@dev_id: Device identity to free
133  *
134  *	Except for the extra @dev argument, this function takes the
135  *	same arguments and performs the same function as free_irq().
136  *	This function instead of free_irq() should be used to manually
137  *	free IRQs allocated with devm_request_irq().
138  */
139 void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id)
140 {
141 	struct irq_devres match_data = { irq, dev_id };
142 
143 	WARN_ON(devres_destroy(dev, devm_irq_release, devm_irq_match,
144 			       &match_data));
145 	free_irq(irq, dev_id);
146 }
147 EXPORT_SYMBOL(devm_free_irq);
148 
149 struct irq_desc_devres {
150 	unsigned int from;
151 	unsigned int cnt;
152 };
153 
154 static void devm_irq_desc_release(struct device *dev, void *res)
155 {
156 	struct irq_desc_devres *this = res;
157 
158 	irq_free_descs(this->from, this->cnt);
159 }
160 
161 /**
162  * __devm_irq_alloc_descs - Allocate and initialize a range of irq descriptors
163  *			    for a managed device
164  * @dev:	Device to allocate the descriptors for
165  * @irq:	Allocate for specific irq number if irq >= 0
166  * @from:	Start the search from this irq number
167  * @cnt:	Number of consecutive irqs to allocate
168  * @node:	Preferred node on which the irq descriptor should be allocated
169  * @owner:	Owning module (can be NULL)
170  * @affinity:	Optional pointer to an irq_affinity_desc array of size @cnt
171  *		which hints where the irq descriptors should be allocated
172  *		and which default affinities to use
173  *
174  * Returns the first irq number or error code.
175  *
176  * Note: Use the provided wrappers (devm_irq_alloc_desc*) for simplicity.
177  */
178 int __devm_irq_alloc_descs(struct device *dev, int irq, unsigned int from,
179 			   unsigned int cnt, int node, struct module *owner,
180 			   const struct irq_affinity_desc *affinity)
181 {
182 	struct irq_desc_devres *dr;
183 	int base;
184 
185 	dr = devres_alloc(devm_irq_desc_release, sizeof(*dr), GFP_KERNEL);
186 	if (!dr)
187 		return -ENOMEM;
188 
189 	base = __irq_alloc_descs(irq, from, cnt, node, owner, affinity);
190 	if (base < 0) {
191 		devres_free(dr);
192 		return base;
193 	}
194 
195 	dr->from = base;
196 	dr->cnt = cnt;
197 	devres_add(dev, dr);
198 
199 	return base;
200 }
201 EXPORT_SYMBOL_GPL(__devm_irq_alloc_descs);
202 
203 #ifdef CONFIG_GENERIC_IRQ_CHIP
204 /**
205  * devm_irq_alloc_generic_chip - Allocate and initialize a generic chip
206  *                               for a managed device
207  * @dev:	Device to allocate the generic chip for
208  * @name:	Name of the irq chip
209  * @num_ct:	Number of irq_chip_type instances associated with this
210  * @irq_base:	Interrupt base nr for this chip
211  * @reg_base:	Register base address (virtual)
212  * @handler:	Default flow handler associated with this chip
213  *
214  * Returns an initialized irq_chip_generic structure. The chip defaults
215  * to the primary (index 0) irq_chip_type and @handler
216  */
217 struct irq_chip_generic *
218 devm_irq_alloc_generic_chip(struct device *dev, const char *name, int num_ct,
219 			    unsigned int irq_base, void __iomem *reg_base,
220 			    irq_flow_handler_t handler)
221 {
222 	struct irq_chip_generic *gc;
223 
224 	gc = devm_kzalloc(dev, struct_size(gc, chip_types, num_ct), GFP_KERNEL);
225 	if (gc)
226 		irq_init_generic_chip(gc, name, num_ct,
227 				      irq_base, reg_base, handler);
228 
229 	return gc;
230 }
231 EXPORT_SYMBOL_GPL(devm_irq_alloc_generic_chip);
232 
233 struct irq_generic_chip_devres {
234 	struct irq_chip_generic *gc;
235 	u32 msk;
236 	unsigned int clr;
237 	unsigned int set;
238 };
239 
240 static void devm_irq_remove_generic_chip(struct device *dev, void *res)
241 {
242 	struct irq_generic_chip_devres *this = res;
243 
244 	irq_remove_generic_chip(this->gc, this->msk, this->clr, this->set);
245 }
246 
247 /**
248  * devm_irq_setup_generic_chip - Setup a range of interrupts with a generic
249  *                               chip for a managed device
250  *
251  * @dev:	Device to setup the generic chip for
252  * @gc:		Generic irq chip holding all data
253  * @msk:	Bitmask holding the irqs to initialize relative to gc->irq_base
254  * @flags:	Flags for initialization
255  * @clr:	IRQ_* bits to clear
256  * @set:	IRQ_* bits to set
257  *
258  * Set up max. 32 interrupts starting from gc->irq_base. Note, this
259  * initializes all interrupts to the primary irq_chip_type and its
260  * associated handler.
261  */
262 int devm_irq_setup_generic_chip(struct device *dev, struct irq_chip_generic *gc,
263 				u32 msk, enum irq_gc_flags flags,
264 				unsigned int clr, unsigned int set)
265 {
266 	struct irq_generic_chip_devres *dr;
267 
268 	dr = devres_alloc(devm_irq_remove_generic_chip,
269 			  sizeof(*dr), GFP_KERNEL);
270 	if (!dr)
271 		return -ENOMEM;
272 
273 	irq_setup_generic_chip(gc, msk, flags, clr, set);
274 
275 	dr->gc = gc;
276 	dr->msk = msk;
277 	dr->clr = clr;
278 	dr->set = set;
279 	devres_add(dev, dr);
280 
281 	return 0;
282 }
283 EXPORT_SYMBOL_GPL(devm_irq_setup_generic_chip);
284 #endif /* CONFIG_GENERIC_IRQ_CHIP */
285