// SPDX-License-Identifier: GPL-2.0+ /* * Copyright (C) 2017-2018 Bartosz Golaszewski <brgl@bgdev.pl> * Copyright (C) 2020 Bartosz Golaszewski <bgolaszewski@baylibre.com> */ #include <linux/irq.h> #include <linux/irq_sim.h> #include <linux/irq_work.h> #include <linux/interrupt.h> #include <linux/slab.h> struct irq_sim_work_ctx { struct irq_work work; int irq_base; unsigned int irq_count; unsigned long *pending; struct irq_domain *domain; }; struct irq_sim_irq_ctx { int irqnum; bool enabled; struct irq_sim_work_ctx *work_ctx; }; static void irq_sim_irqmask(struct irq_data *data) { struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data); irq_ctx->enabled = false; } static void irq_sim_irqunmask(struct irq_data *data) { struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data); irq_ctx->enabled = true; } static int irq_sim_set_type(struct irq_data *data, unsigned int type) { /* We only support rising and falling edge trigger types. */ if (type & ~IRQ_TYPE_EDGE_BOTH) return -EINVAL; irqd_set_trigger_type(data, type); return 0; } static int irq_sim_get_irqchip_state(struct irq_data *data, enum irqchip_irq_state which, bool *state) { struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data); irq_hw_number_t hwirq = irqd_to_hwirq(data); switch (which) { case IRQCHIP_STATE_PENDING: if (irq_ctx->enabled) *state = test_bit(hwirq, irq_ctx->work_ctx->pending); break; default: return -EINVAL; } return 0; } static int irq_sim_set_irqchip_state(struct irq_data *data, enum irqchip_irq_state which, bool state) { struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data); irq_hw_number_t hwirq = irqd_to_hwirq(data); switch (which) { case IRQCHIP_STATE_PENDING: if (irq_ctx->enabled) { assign_bit(hwirq, irq_ctx->work_ctx->pending, state); if (state) irq_work_queue(&irq_ctx->work_ctx->work); } break; default: return -EINVAL; } return 0; } static struct irq_chip irq_sim_irqchip = { .name = "irq_sim", .irq_mask = irq_sim_irqmask, .irq_unmask = irq_sim_irqunmask, .irq_set_type = irq_sim_set_type, .irq_get_irqchip_state = irq_sim_get_irqchip_state, .irq_set_irqchip_state = irq_sim_set_irqchip_state, }; static void irq_sim_handle_irq(struct irq_work *work) { struct irq_sim_work_ctx *work_ctx; unsigned int offset = 0; int irqnum; work_ctx = container_of(work, struct irq_sim_work_ctx, work); while (!bitmap_empty(work_ctx->pending, work_ctx->irq_count)) { offset = find_next_bit(work_ctx->pending, work_ctx->irq_count, offset); clear_bit(offset, work_ctx->pending); irqnum = irq_find_mapping(work_ctx->domain, offset); handle_simple_irq(irq_to_desc(irqnum)); } } static int irq_sim_domain_map(struct irq_domain *domain, unsigned int virq, irq_hw_number_t hw) { struct irq_sim_work_ctx *work_ctx = domain->host_data; struct irq_sim_irq_ctx *irq_ctx; irq_ctx = kzalloc(sizeof(*irq_ctx), GFP_KERNEL); if (!irq_ctx) return -ENOMEM; irq_set_chip(virq, &irq_sim_irqchip); irq_set_chip_data(virq, irq_ctx); irq_set_handler(virq, handle_simple_irq); irq_modify_status(virq, IRQ_NOREQUEST | IRQ_NOAUTOEN, IRQ_NOPROBE); irq_ctx->work_ctx = work_ctx; return 0; } static void irq_sim_domain_unmap(struct irq_domain *domain, unsigned int virq) { struct irq_sim_irq_ctx *irq_ctx; struct irq_data *irqd; irqd = irq_domain_get_irq_data(domain, virq); irq_ctx = irq_data_get_irq_chip_data(irqd); irq_set_handler(virq, NULL); irq_domain_reset_irq_data(irqd); kfree(irq_ctx); } static const struct irq_domain_ops irq_sim_domain_ops = { .map = irq_sim_domain_map, .unmap = irq_sim_domain_unmap, }; /** * irq_domain_create_sim - Create a new interrupt simulator irq_domain and * allocate a range of dummy interrupts. * * @fwnode: struct fwnode_handle to be associated with this domain. * @num_irqs: Number of interrupts to allocate. * * On success: return a new irq_domain object. * On failure: a negative errno wrapped with ERR_PTR(). */ struct irq_domain *irq_domain_create_sim(struct fwnode_handle *fwnode, unsigned int num_irqs) { struct irq_sim_work_ctx *work_ctx; work_ctx = kmalloc(sizeof(*work_ctx), GFP_KERNEL); if (!work_ctx) goto err_out; work_ctx->pending = bitmap_zalloc(num_irqs, GFP_KERNEL); if (!work_ctx->pending) goto err_free_work_ctx; work_ctx->domain = irq_domain_create_linear(fwnode, num_irqs, &irq_sim_domain_ops, work_ctx); if (!work_ctx->domain) goto err_free_bitmap; work_ctx->irq_count = num_irqs; work_ctx->work = IRQ_WORK_INIT_HARD(irq_sim_handle_irq); return work_ctx->domain; err_free_bitmap: bitmap_free(work_ctx->pending); err_free_work_ctx: kfree(work_ctx); err_out: return ERR_PTR(-ENOMEM); } EXPORT_SYMBOL_GPL(irq_domain_create_sim); /** * irq_domain_remove_sim - Deinitialize the interrupt simulator domain: free * the interrupt descriptors and allocated memory. * * @domain: The interrupt simulator domain to tear down. */ void irq_domain_remove_sim(struct irq_domain *domain) { struct irq_sim_work_ctx *work_ctx = domain->host_data; irq_work_sync(&work_ctx->work); bitmap_free(work_ctx->pending); kfree(work_ctx); irq_domain_remove(domain); } EXPORT_SYMBOL_GPL(irq_domain_remove_sim); static void devm_irq_domain_remove_sim(void *data) { struct irq_domain *domain = data; irq_domain_remove_sim(domain); } /** * devm_irq_domain_create_sim - Create a new interrupt simulator for * a managed device. * * @dev: Device to initialize the simulator object for. * @fwnode: struct fwnode_handle to be associated with this domain. * @num_irqs: Number of interrupts to allocate * * On success: return a new irq_domain object. * On failure: a negative errno wrapped with ERR_PTR(). */ struct irq_domain *devm_irq_domain_create_sim(struct device *dev, struct fwnode_handle *fwnode, unsigned int num_irqs) { struct irq_domain *domain; int ret; domain = irq_domain_create_sim(fwnode, num_irqs); if (IS_ERR(domain)) return domain; ret = devm_add_action_or_reset(dev, devm_irq_domain_remove_sim, domain); if (ret) return ERR_PTR(ret); return domain; } EXPORT_SYMBOL_GPL(devm_irq_domain_create_sim);