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v5.4
  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * Copyright (C) 2017-2018 Bartosz Golaszewski <brgl@bgdev.pl>
 
  4 */
  5
  6#include <linux/slab.h>
  7#include <linux/irq_sim.h>
  8#include <linux/irq.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  9
 10struct irq_sim_devres {
 11	struct irq_sim		*sim;
 12};
 13
 14static void irq_sim_irqmask(struct irq_data *data)
 15{
 16	struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
 17
 18	irq_ctx->enabled = false;
 19}
 20
 21static void irq_sim_irqunmask(struct irq_data *data)
 22{
 23	struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
 24
 25	irq_ctx->enabled = true;
 26}
 27
 28static int irq_sim_set_type(struct irq_data *data, unsigned int type)
 29{
 30	/* We only support rising and falling edge trigger types. */
 31	if (type & ~IRQ_TYPE_EDGE_BOTH)
 32		return -EINVAL;
 33
 34	irqd_set_trigger_type(data, type);
 35
 36	return 0;
 37}
 38
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 39static struct irq_chip irq_sim_irqchip = {
 40	.name		= "irq_sim",
 41	.irq_mask	= irq_sim_irqmask,
 42	.irq_unmask	= irq_sim_irqunmask,
 43	.irq_set_type	= irq_sim_set_type,
 
 
 44};
 45
 46static void irq_sim_handle_irq(struct irq_work *work)
 47{
 48	struct irq_sim_work_ctx *work_ctx;
 49	unsigned int offset = 0;
 50	struct irq_sim *sim;
 51	int irqnum;
 52
 53	work_ctx = container_of(work, struct irq_sim_work_ctx, work);
 54	sim = container_of(work_ctx, struct irq_sim, work_ctx);
 55
 56	while (!bitmap_empty(work_ctx->pending, sim->irq_count)) {
 57		offset = find_next_bit(work_ctx->pending,
 58				       sim->irq_count, offset);
 59		clear_bit(offset, work_ctx->pending);
 60		irqnum = irq_sim_irqnum(sim, offset);
 61		handle_simple_irq(irq_to_desc(irqnum));
 62	}
 63}
 64
 65/**
 66 * irq_sim_init - Initialize the interrupt simulator: allocate a range of
 67 *                dummy interrupts.
 68 *
 69 * @sim:        The interrupt simulator object to initialize.
 70 * @num_irqs:   Number of interrupts to allocate
 71 *
 72 * On success: return the base of the allocated interrupt range.
 73 * On failure: a negative errno.
 74 */
 75int irq_sim_init(struct irq_sim *sim, unsigned int num_irqs)
 76{
 77	int i;
 
 78
 79	sim->irqs = kmalloc_array(num_irqs, sizeof(*sim->irqs), GFP_KERNEL);
 80	if (!sim->irqs)
 81		return -ENOMEM;
 82
 83	sim->irq_base = irq_alloc_descs(-1, 0, num_irqs, 0);
 84	if (sim->irq_base < 0) {
 85		kfree(sim->irqs);
 86		return sim->irq_base;
 87	}
 88
 89	sim->work_ctx.pending = bitmap_zalloc(num_irqs, GFP_KERNEL);
 90	if (!sim->work_ctx.pending) {
 91		kfree(sim->irqs);
 92		irq_free_descs(sim->irq_base, num_irqs);
 93		return -ENOMEM;
 94	}
 95
 96	for (i = 0; i < num_irqs; i++) {
 97		sim->irqs[i].irqnum = sim->irq_base + i;
 98		sim->irqs[i].enabled = false;
 99		irq_set_chip(sim->irq_base + i, &irq_sim_irqchip);
100		irq_set_chip_data(sim->irq_base + i, &sim->irqs[i]);
101		irq_set_handler(sim->irq_base + i, &handle_simple_irq);
102		irq_modify_status(sim->irq_base + i,
103				  IRQ_NOREQUEST | IRQ_NOAUTOEN, IRQ_NOPROBE);
104	}
105
106	init_irq_work(&sim->work_ctx.work, irq_sim_handle_irq);
107	sim->irq_count = num_irqs;
108
109	return sim->irq_base;
 
 
110}
111EXPORT_SYMBOL_GPL(irq_sim_init);
 
 
 
 
112
113/**
114 * irq_sim_fini - Deinitialize the interrupt simulator: free the interrupt
115 *                descriptors and allocated memory.
116 *
117 * @sim:        The interrupt simulator to tear down.
 
 
 
 
118 */
119void irq_sim_fini(struct irq_sim *sim)
 
120{
121	irq_work_sync(&sim->work_ctx.work);
122	bitmap_free(sim->work_ctx.pending);
123	irq_free_descs(sim->irq_base, sim->irq_count);
124	kfree(sim->irqs);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
125}
126EXPORT_SYMBOL_GPL(irq_sim_fini);
127
128static void devm_irq_sim_release(struct device *dev, void *res)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
129{
130	struct irq_sim_devres *this = res;
131
132	irq_sim_fini(this->sim);
133}
134
135/**
136 * irq_sim_init - Initialize the interrupt simulator for a managed device.
 
137 *
138 * @dev:        Device to initialize the simulator object for.
139 * @sim:        The interrupt simulator object to initialize.
140 * @num_irqs:   Number of interrupts to allocate
141 *
142 * On success: return the base of the allocated interrupt range.
143 * On failure: a negative errno.
144 */
145int devm_irq_sim_init(struct device *dev, struct irq_sim *sim,
146		      unsigned int num_irqs)
 
147{
148	struct irq_sim_devres *dr;
149	int rv;
150
151	dr = devres_alloc(devm_irq_sim_release, sizeof(*dr), GFP_KERNEL);
 
152	if (!dr)
153		return -ENOMEM;
154
155	rv = irq_sim_init(sim, num_irqs);
156	if (rv < 0) {
157		devres_free(dr);
158		return rv;
159	}
160
161	dr->sim = sim;
162	devres_add(dev, dr);
163
164	return rv;
165}
166EXPORT_SYMBOL_GPL(devm_irq_sim_init);
167
168/**
169 * irq_sim_fire - Enqueue an interrupt.
170 *
171 * @sim:        The interrupt simulator object.
172 * @offset:     Offset of the simulated interrupt which should be fired.
173 */
174void irq_sim_fire(struct irq_sim *sim, unsigned int offset)
175{
176	if (sim->irqs[offset].enabled) {
177		set_bit(offset, sim->work_ctx.pending);
178		irq_work_queue(&sim->work_ctx.work);
179	}
180}
181EXPORT_SYMBOL_GPL(irq_sim_fire);
182
183/**
184 * irq_sim_irqnum - Get the allocated number of a dummy interrupt.
185 *
186 * @sim:        The interrupt simulator object.
187 * @offset:     Offset of the simulated interrupt for which to retrieve
188 *              the number.
189 */
190int irq_sim_irqnum(struct irq_sim *sim, unsigned int offset)
191{
192	return sim->irqs[offset].irqnum;
193}
194EXPORT_SYMBOL_GPL(irq_sim_irqnum);
v5.9
  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);