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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright (C) 2017-2018 Bartosz Golaszewski <brgl@bgdev.pl>
4 * Copyright (C) 2020 Bartosz Golaszewski <bgolaszewski@baylibre.com>
5 */
6
7#include <linux/irq.h>
8#include <linux/irq_sim.h>
9#include <linux/irq_work.h>
10#include <linux/interrupt.h>
11#include <linux/slab.h>
12
13struct irq_sim_work_ctx {
14 struct irq_work work;
15 int irq_base;
16 unsigned int irq_count;
17 unsigned long *pending;
18 struct irq_domain *domain;
19};
20
21struct irq_sim_irq_ctx {
22 int irqnum;
23 bool enabled;
24 struct irq_sim_work_ctx *work_ctx;
25};
26
27struct irq_sim_devres {
28 struct irq_domain *domain;
29};
30
31static void irq_sim_irqmask(struct irq_data *data)
32{
33 struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
34
35 irq_ctx->enabled = false;
36}
37
38static void irq_sim_irqunmask(struct irq_data *data)
39{
40 struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
41
42 irq_ctx->enabled = true;
43}
44
45static int irq_sim_set_type(struct irq_data *data, unsigned int type)
46{
47 /* We only support rising and falling edge trigger types. */
48 if (type & ~IRQ_TYPE_EDGE_BOTH)
49 return -EINVAL;
50
51 irqd_set_trigger_type(data, type);
52
53 return 0;
54}
55
56static int irq_sim_get_irqchip_state(struct irq_data *data,
57 enum irqchip_irq_state which, bool *state)
58{
59 struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
60 irq_hw_number_t hwirq = irqd_to_hwirq(data);
61
62 switch (which) {
63 case IRQCHIP_STATE_PENDING:
64 if (irq_ctx->enabled)
65 *state = test_bit(hwirq, irq_ctx->work_ctx->pending);
66 break;
67 default:
68 return -EINVAL;
69 }
70
71 return 0;
72}
73
74static int irq_sim_set_irqchip_state(struct irq_data *data,
75 enum irqchip_irq_state which, bool state)
76{
77 struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
78 irq_hw_number_t hwirq = irqd_to_hwirq(data);
79
80 switch (which) {
81 case IRQCHIP_STATE_PENDING:
82 if (irq_ctx->enabled) {
83 assign_bit(hwirq, irq_ctx->work_ctx->pending, state);
84 if (state)
85 irq_work_queue(&irq_ctx->work_ctx->work);
86 }
87 break;
88 default:
89 return -EINVAL;
90 }
91
92 return 0;
93}
94
95static struct irq_chip irq_sim_irqchip = {
96 .name = "irq_sim",
97 .irq_mask = irq_sim_irqmask,
98 .irq_unmask = irq_sim_irqunmask,
99 .irq_set_type = irq_sim_set_type,
100 .irq_get_irqchip_state = irq_sim_get_irqchip_state,
101 .irq_set_irqchip_state = irq_sim_set_irqchip_state,
102};
103
104static void irq_sim_handle_irq(struct irq_work *work)
105{
106 struct irq_sim_work_ctx *work_ctx;
107 unsigned int offset = 0;
108 int irqnum;
109
110 work_ctx = container_of(work, struct irq_sim_work_ctx, work);
111
112 while (!bitmap_empty(work_ctx->pending, work_ctx->irq_count)) {
113 offset = find_next_bit(work_ctx->pending,
114 work_ctx->irq_count, offset);
115 clear_bit(offset, work_ctx->pending);
116 irqnum = irq_find_mapping(work_ctx->domain, offset);
117 handle_simple_irq(irq_to_desc(irqnum));
118 }
119}
120
121static int irq_sim_domain_map(struct irq_domain *domain,
122 unsigned int virq, irq_hw_number_t hw)
123{
124 struct irq_sim_work_ctx *work_ctx = domain->host_data;
125 struct irq_sim_irq_ctx *irq_ctx;
126
127 irq_ctx = kzalloc(sizeof(*irq_ctx), GFP_KERNEL);
128 if (!irq_ctx)
129 return -ENOMEM;
130
131 irq_set_chip(virq, &irq_sim_irqchip);
132 irq_set_chip_data(virq, irq_ctx);
133 irq_set_handler(virq, handle_simple_irq);
134 irq_modify_status(virq, IRQ_NOREQUEST | IRQ_NOAUTOEN, IRQ_NOPROBE);
135 irq_ctx->work_ctx = work_ctx;
136
137 return 0;
138}
139
140static void irq_sim_domain_unmap(struct irq_domain *domain, unsigned int virq)
141{
142 struct irq_sim_irq_ctx *irq_ctx;
143 struct irq_data *irqd;
144
145 irqd = irq_domain_get_irq_data(domain, virq);
146 irq_ctx = irq_data_get_irq_chip_data(irqd);
147
148 irq_set_handler(virq, NULL);
149 irq_domain_reset_irq_data(irqd);
150 kfree(irq_ctx);
151}
152
153static const struct irq_domain_ops irq_sim_domain_ops = {
154 .map = irq_sim_domain_map,
155 .unmap = irq_sim_domain_unmap,
156};
157
158/**
159 * irq_domain_create_sim - Create a new interrupt simulator irq_domain and
160 * allocate a range of dummy interrupts.
161 *
162 * @fnode: struct fwnode_handle to be associated with this domain.
163 * @num_irqs: Number of interrupts to allocate.
164 *
165 * On success: return a new irq_domain object.
166 * On failure: a negative errno wrapped with ERR_PTR().
167 */
168struct irq_domain *irq_domain_create_sim(struct fwnode_handle *fwnode,
169 unsigned int num_irqs)
170{
171 struct irq_sim_work_ctx *work_ctx;
172
173 work_ctx = kmalloc(sizeof(*work_ctx), GFP_KERNEL);
174 if (!work_ctx)
175 goto err_out;
176
177 work_ctx->pending = bitmap_zalloc(num_irqs, GFP_KERNEL);
178 if (!work_ctx->pending)
179 goto err_free_work_ctx;
180
181 work_ctx->domain = irq_domain_create_linear(fwnode, num_irqs,
182 &irq_sim_domain_ops,
183 work_ctx);
184 if (!work_ctx->domain)
185 goto err_free_bitmap;
186
187 work_ctx->irq_count = num_irqs;
188 init_irq_work(&work_ctx->work, irq_sim_handle_irq);
189
190 return work_ctx->domain;
191
192err_free_bitmap:
193 bitmap_free(work_ctx->pending);
194err_free_work_ctx:
195 kfree(work_ctx);
196err_out:
197 return ERR_PTR(-ENOMEM);
198}
199EXPORT_SYMBOL_GPL(irq_domain_create_sim);
200
201/**
202 * irq_domain_remove_sim - Deinitialize the interrupt simulator domain: free
203 * the interrupt descriptors and allocated memory.
204 *
205 * @domain: The interrupt simulator domain to tear down.
206 */
207void irq_domain_remove_sim(struct irq_domain *domain)
208{
209 struct irq_sim_work_ctx *work_ctx = domain->host_data;
210
211 irq_work_sync(&work_ctx->work);
212 bitmap_free(work_ctx->pending);
213 kfree(work_ctx);
214
215 irq_domain_remove(domain);
216}
217EXPORT_SYMBOL_GPL(irq_domain_remove_sim);
218
219static void devm_irq_domain_release_sim(struct device *dev, void *res)
220{
221 struct irq_sim_devres *this = res;
222
223 irq_domain_remove_sim(this->domain);
224}
225
226/**
227 * devm_irq_domain_create_sim - Create a new interrupt simulator for
228 * a managed device.
229 *
230 * @dev: Device to initialize the simulator object for.
231 * @fnode: struct fwnode_handle to be associated with this domain.
232 * @num_irqs: Number of interrupts to allocate
233 *
234 * On success: return a new irq_domain object.
235 * On failure: a negative errno wrapped with ERR_PTR().
236 */
237struct irq_domain *devm_irq_domain_create_sim(struct device *dev,
238 struct fwnode_handle *fwnode,
239 unsigned int num_irqs)
240{
241 struct irq_sim_devres *dr;
242
243 dr = devres_alloc(devm_irq_domain_release_sim,
244 sizeof(*dr), GFP_KERNEL);
245 if (!dr)
246 return ERR_PTR(-ENOMEM);
247
248 dr->domain = irq_domain_create_sim(fwnode, num_irqs);
249 if (IS_ERR(dr->domain)) {
250 devres_free(dr);
251 return dr->domain;
252 }
253
254 devres_add(dev, dr);
255 return dr->domain;
256}
257EXPORT_SYMBOL_GPL(devm_irq_domain_create_sim);
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright (C) 2017 Bartosz Golaszewski <brgl@bgdev.pl>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version.
9 */
10
11#include <linux/slab.h>
12#include <linux/irq_sim.h>
13#include <linux/irq.h>
14
15struct irq_sim_devres {
16 struct irq_sim *sim;
17};
18
19static void irq_sim_irqmask(struct irq_data *data)
20{
21 struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
22
23 irq_ctx->enabled = false;
24}
25
26static void irq_sim_irqunmask(struct irq_data *data)
27{
28 struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
29
30 irq_ctx->enabled = true;
31}
32
33static struct irq_chip irq_sim_irqchip = {
34 .name = "irq_sim",
35 .irq_mask = irq_sim_irqmask,
36 .irq_unmask = irq_sim_irqunmask,
37};
38
39static void irq_sim_handle_irq(struct irq_work *work)
40{
41 struct irq_sim_work_ctx *work_ctx;
42
43 work_ctx = container_of(work, struct irq_sim_work_ctx, work);
44 handle_simple_irq(irq_to_desc(work_ctx->irq));
45}
46
47/**
48 * irq_sim_init - Initialize the interrupt simulator: allocate a range of
49 * dummy interrupts.
50 *
51 * @sim: The interrupt simulator object to initialize.
52 * @num_irqs: Number of interrupts to allocate
53 *
54 * On success: return the base of the allocated interrupt range.
55 * On failure: a negative errno.
56 */
57int irq_sim_init(struct irq_sim *sim, unsigned int num_irqs)
58{
59 int i;
60
61 sim->irqs = kmalloc_array(num_irqs, sizeof(*sim->irqs), GFP_KERNEL);
62 if (!sim->irqs)
63 return -ENOMEM;
64
65 sim->irq_base = irq_alloc_descs(-1, 0, num_irqs, 0);
66 if (sim->irq_base < 0) {
67 kfree(sim->irqs);
68 return sim->irq_base;
69 }
70
71 for (i = 0; i < num_irqs; i++) {
72 sim->irqs[i].irqnum = sim->irq_base + i;
73 sim->irqs[i].enabled = false;
74 irq_set_chip(sim->irq_base + i, &irq_sim_irqchip);
75 irq_set_chip_data(sim->irq_base + i, &sim->irqs[i]);
76 irq_set_handler(sim->irq_base + i, &handle_simple_irq);
77 irq_modify_status(sim->irq_base + i,
78 IRQ_NOREQUEST | IRQ_NOAUTOEN, IRQ_NOPROBE);
79 }
80
81 init_irq_work(&sim->work_ctx.work, irq_sim_handle_irq);
82 sim->irq_count = num_irqs;
83
84 return sim->irq_base;
85}
86EXPORT_SYMBOL_GPL(irq_sim_init);
87
88/**
89 * irq_sim_fini - Deinitialize the interrupt simulator: free the interrupt
90 * descriptors and allocated memory.
91 *
92 * @sim: The interrupt simulator to tear down.
93 */
94void irq_sim_fini(struct irq_sim *sim)
95{
96 irq_work_sync(&sim->work_ctx.work);
97 irq_free_descs(sim->irq_base, sim->irq_count);
98 kfree(sim->irqs);
99}
100EXPORT_SYMBOL_GPL(irq_sim_fini);
101
102static void devm_irq_sim_release(struct device *dev, void *res)
103{
104 struct irq_sim_devres *this = res;
105
106 irq_sim_fini(this->sim);
107}
108
109/**
110 * irq_sim_init - Initialize the interrupt simulator for a managed device.
111 *
112 * @dev: Device to initialize the simulator object for.
113 * @sim: The interrupt simulator object to initialize.
114 * @num_irqs: Number of interrupts to allocate
115 *
116 * On success: return the base of the allocated interrupt range.
117 * On failure: a negative errno.
118 */
119int devm_irq_sim_init(struct device *dev, struct irq_sim *sim,
120 unsigned int num_irqs)
121{
122 struct irq_sim_devres *dr;
123 int rv;
124
125 dr = devres_alloc(devm_irq_sim_release, sizeof(*dr), GFP_KERNEL);
126 if (!dr)
127 return -ENOMEM;
128
129 rv = irq_sim_init(sim, num_irqs);
130 if (rv < 0) {
131 devres_free(dr);
132 return rv;
133 }
134
135 dr->sim = sim;
136 devres_add(dev, dr);
137
138 return rv;
139}
140EXPORT_SYMBOL_GPL(devm_irq_sim_init);
141
142/**
143 * irq_sim_fire - Enqueue an interrupt.
144 *
145 * @sim: The interrupt simulator object.
146 * @offset: Offset of the simulated interrupt which should be fired.
147 */
148void irq_sim_fire(struct irq_sim *sim, unsigned int offset)
149{
150 if (sim->irqs[offset].enabled) {
151 sim->work_ctx.irq = irq_sim_irqnum(sim, offset);
152 irq_work_queue(&sim->work_ctx.work);
153 }
154}
155EXPORT_SYMBOL_GPL(irq_sim_fire);
156
157/**
158 * irq_sim_irqnum - Get the allocated number of a dummy interrupt.
159 *
160 * @sim: The interrupt simulator object.
161 * @offset: Offset of the simulated interrupt for which to retrieve
162 * the number.
163 */
164int irq_sim_irqnum(struct irq_sim *sim, unsigned int offset)
165{
166 return sim->irqs[offset].irqnum;
167}
168EXPORT_SYMBOL_GPL(irq_sim_irqnum);