projects/linux·blob master · refs

297 lines · 7.8 KiB

1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright (C) 2017-2018 Bartosz Golaszewski <[email protected]>
4 * Copyright (C) 2020 Bartosz Golaszewski <[email protected]>
5 */
6
7#include <linux/cleanup.h>
8#include <linux/interrupt.h>
9#include <linux/irq.h>
10#include <linux/irq_sim.h>
11#include <linux/irq_work.h>
12#include <linux/slab.h>
13
14struct irq_sim_work_ctx {
15 struct irq_work work;
16 unsigned int irq_count;
17 unsigned long *pending;
18 struct irq_domain *domain;
19 struct irq_sim_ops ops;
20 void *user_data;
21};
22
23struct irq_sim_irq_ctx {
24 bool enabled;
25 struct irq_sim_work_ctx *work_ctx;
26};
27
28static void irq_sim_irqmask(struct irq_data *data)
29{
30 struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
31
32 irq_ctx->enabled = false;
33}
34
35static void irq_sim_irqunmask(struct irq_data *data)
36{
37 struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
38
39 irq_ctx->enabled = true;
40}
41
42static int irq_sim_set_type(struct irq_data *data, unsigned int type)
43{
44 /* We only support rising and falling edge trigger types. */
45 if (type & ~IRQ_TYPE_EDGE_BOTH)
46 return -EINVAL;
47
48 irqd_set_trigger_type(data, type);
49
50 return 0;
51}
52
53static int irq_sim_get_irqchip_state(struct irq_data *data,
54 enum irqchip_irq_state which, bool *state)
55{
56 struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
57 irq_hw_number_t hwirq = irqd_to_hwirq(data);
58
59 switch (which) {
60 case IRQCHIP_STATE_PENDING:
61 if (irq_ctx->enabled)
62 *state = test_bit(hwirq, irq_ctx->work_ctx->pending);
63 break;
64 default:
65 return -EINVAL;
66 }
67
68 return 0;
69}
70
71static int irq_sim_set_irqchip_state(struct irq_data *data,
72 enum irqchip_irq_state which, bool state)
73{
74 struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
75 irq_hw_number_t hwirq = irqd_to_hwirq(data);
76
77 switch (which) {
78 case IRQCHIP_STATE_PENDING:
79 if (irq_ctx->enabled) {
80 assign_bit(hwirq, irq_ctx->work_ctx->pending, state);
81 if (state)
82 irq_work_queue(&irq_ctx->work_ctx->work);
83 }
84 break;
85 default:
86 return -EINVAL;
87 }
88
89 return 0;
90}
91
92static int irq_sim_request_resources(struct irq_data *data)
93{
94 struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
95 struct irq_sim_work_ctx *work_ctx = irq_ctx->work_ctx;
96 irq_hw_number_t hwirq = irqd_to_hwirq(data);
97
98 if (work_ctx->ops.irq_sim_irq_requested)
99 return work_ctx->ops.irq_sim_irq_requested(work_ctx->domain,
100 hwirq,
101 work_ctx->user_data);
102
103 return 0;
104}
105
106static void irq_sim_release_resources(struct irq_data *data)
107{
108 struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
109 struct irq_sim_work_ctx *work_ctx = irq_ctx->work_ctx;
110 irq_hw_number_t hwirq = irqd_to_hwirq(data);
111
112 if (work_ctx->ops.irq_sim_irq_released)
113 work_ctx->ops.irq_sim_irq_released(work_ctx->domain, hwirq,
114 work_ctx->user_data);
115}
116
117static struct irq_chip irq_sim_irqchip = {
118 .name = "irq_sim",
119 .irq_mask = irq_sim_irqmask,
120 .irq_unmask = irq_sim_irqunmask,
121 .irq_set_type = irq_sim_set_type,
122 .irq_get_irqchip_state = irq_sim_get_irqchip_state,
123 .irq_set_irqchip_state = irq_sim_set_irqchip_state,
124 .irq_request_resources = irq_sim_request_resources,
125 .irq_release_resources = irq_sim_release_resources,
126};
127
128static void irq_sim_handle_irq(struct irq_work *work)
129{
130 struct irq_sim_work_ctx *work_ctx;
131 unsigned int offset = 0;
132 int irqnum;
133
134 work_ctx = container_of(work, struct irq_sim_work_ctx, work);
135
136 while (!bitmap_empty(work_ctx->pending, work_ctx->irq_count)) {
137 offset = find_next_bit(work_ctx->pending,
138 work_ctx->irq_count, offset);
139 clear_bit(offset, work_ctx->pending);
140 irqnum = irq_find_mapping(work_ctx->domain, offset);
141 handle_simple_irq(irq_to_desc(irqnum));
142 }
143}
144
145static int irq_sim_domain_map(struct irq_domain *domain,
146 unsigned int virq, irq_hw_number_t hw)
147{
148 struct irq_sim_work_ctx *work_ctx = domain->host_data;
149 struct irq_sim_irq_ctx *irq_ctx;
150
151 irq_ctx = kzalloc_obj(*irq_ctx);
152 if (!irq_ctx)
153 return -ENOMEM;
154
155 irq_set_chip(virq, &irq_sim_irqchip);
156 irq_set_chip_data(virq, irq_ctx);
157 irq_set_handler(virq, handle_simple_irq);
158 irq_modify_status(virq, IRQ_NOREQUEST | IRQ_NOAUTOEN, IRQ_NOPROBE);
159 irq_ctx->work_ctx = work_ctx;
160
161 return 0;
162}
163
164static void irq_sim_domain_unmap(struct irq_domain *domain, unsigned int virq)
165{
166 struct irq_sim_irq_ctx *irq_ctx;
167 struct irq_data *irqd;
168
169 irqd = irq_domain_get_irq_data(domain, virq);
170 irq_ctx = irq_data_get_irq_chip_data(irqd);
171
172 irq_set_handler(virq, NULL);
173 irq_domain_reset_irq_data(irqd);
174 kfree(irq_ctx);
175}
176
177static const struct irq_domain_ops irq_sim_domain_ops = {
178 .map = irq_sim_domain_map,
179 .unmap = irq_sim_domain_unmap,
180};
181
182/**
183 * irq_domain_create_sim - Create a new interrupt simulator irq_domain and
184 * allocate a range of dummy interrupts.
185 *
186 * @fwnode: struct fwnode_handle to be associated with this domain.
187 * @num_irqs: Number of interrupts to allocate.
188 *
189 * On success: return a new irq_domain object.
190 * On failure: a negative errno wrapped with ERR_PTR().
191 */
192struct irq_domain *irq_domain_create_sim(struct fwnode_handle *fwnode,
193 unsigned int num_irqs)
194{
195 return irq_domain_create_sim_full(fwnode, num_irqs, NULL, NULL);
196}
197EXPORT_SYMBOL_GPL(irq_domain_create_sim);
198
199struct irq_domain *irq_domain_create_sim_full(struct fwnode_handle *fwnode,
200 unsigned int num_irqs,
201 const struct irq_sim_ops *ops,
202 void *data)
203{
204 struct irq_sim_work_ctx *work_ctx __free(kfree) =
205 kzalloc_obj(*work_ctx);
206
207 if (!work_ctx)
208 return ERR_PTR(-ENOMEM);
209
210 unsigned long *pending __free(bitmap) = bitmap_zalloc(num_irqs, GFP_KERNEL);
211 if (!pending)
212 return ERR_PTR(-ENOMEM);
213
214 work_ctx->domain = irq_domain_create_linear(fwnode, num_irqs,
215 &irq_sim_domain_ops,
216 work_ctx);
217 if (!work_ctx->domain)
218 return ERR_PTR(-ENOMEM);
219
220 work_ctx->irq_count = num_irqs;
221 work_ctx->work = IRQ_WORK_INIT_HARD(irq_sim_handle_irq);
222 work_ctx->pending = no_free_ptr(pending);
223 work_ctx->user_data = data;
224
225 if (ops)
226 memcpy(&work_ctx->ops, ops, sizeof(*ops));
227
228 return no_free_ptr(work_ctx)->domain;
229}
230EXPORT_SYMBOL_GPL(irq_domain_create_sim_full);
231
232/**
233 * irq_domain_remove_sim - Deinitialize the interrupt simulator domain: free
234 * the interrupt descriptors and allocated memory.
235 *
236 * @domain: The interrupt simulator domain to tear down.
237 */
238void irq_domain_remove_sim(struct irq_domain *domain)
239{
240 struct irq_sim_work_ctx *work_ctx = domain->host_data;
241
242 irq_work_sync(&work_ctx->work);
243 bitmap_free(work_ctx->pending);
244 kfree(work_ctx);
245
246 irq_domain_remove(domain);
247}
248EXPORT_SYMBOL_GPL(irq_domain_remove_sim);
249
250static void devm_irq_domain_remove_sim(void *data)
251{
252 struct irq_domain *domain = data;
253
254 irq_domain_remove_sim(domain);
255}
256
257/**
258 * devm_irq_domain_create_sim - Create a new interrupt simulator for
259 * a managed device.
260 *
261 * @dev: Device to initialize the simulator object for.
262 * @fwnode: struct fwnode_handle to be associated with this domain.
263 * @num_irqs: Number of interrupts to allocate
264 *
265 * On success: return a new irq_domain object.
266 * On failure: a negative errno wrapped with ERR_PTR().
267 */
268struct irq_domain *devm_irq_domain_create_sim(struct device *dev,
269 struct fwnode_handle *fwnode,
270 unsigned int num_irqs)
271{
272 return devm_irq_domain_create_sim_full(dev, fwnode, num_irqs,
273 NULL, NULL);
274}
275EXPORT_SYMBOL_GPL(devm_irq_domain_create_sim);
276
277struct irq_domain *
278devm_irq_domain_create_sim_full(struct device *dev,
279 struct fwnode_handle *fwnode,
280 unsigned int num_irqs,
281 const struct irq_sim_ops *ops,
282 void *data)
283{
284 struct irq_domain *domain;
285 int ret;
286
287 domain = irq_domain_create_sim_full(fwnode, num_irqs, ops, data);
288 if (IS_ERR(domain))
289 return domain;
290
291 ret = devm_add_action_or_reset(dev, devm_irq_domain_remove_sim, domain);
292 if (ret)
293 return ERR_PTR(ret);
294
295 return domain;
296}
297EXPORT_SYMBOL_GPL(devm_irq_domain_create_sim_full);