1 #include <linux/irq.h> 2 #include <linux/irqdomain.h> 3 #include <linux/module.h> 4 #include <linux/mutex.h> 5 #include <linux/of.h> 6 #include <linux/of_address.h> 7 #include <linux/slab.h> 8 9 static LIST_HEAD(irq_domain_list); 10 static DEFINE_MUTEX(irq_domain_mutex); 11 12 /** 13 * irq_domain_add() - Register an irq_domain 14 * @domain: ptr to initialized irq_domain structure 15 * 16 * Registers an irq_domain structure. The irq_domain must at a minimum be 17 * initialized with an ops structure pointer, and either a ->to_irq hook or 18 * a valid irq_base value. Everything else is optional. 19 */ 20 void irq_domain_add(struct irq_domain *domain) 21 { 22 struct irq_data *d; 23 int hwirq; 24 25 /* 26 * This assumes that the irq_domain owner has already allocated 27 * the irq_descs. This block will be removed when support for dynamic 28 * allocation of irq_descs is added to irq_domain. 29 */ 30 for (hwirq = 0; hwirq < domain->nr_irq; hwirq++) { 31 d = irq_get_irq_data(irq_domain_to_irq(domain, hwirq)); 32 if (d || d->domain) { 33 /* things are broken; just report, don't clean up */ 34 WARN(1, "error: irq_desc already assigned to a domain"); 35 return; 36 } 37 d->domain = domain; 38 d->hwirq = hwirq; 39 } 40 41 mutex_lock(&irq_domain_mutex); 42 list_add(&domain->list, &irq_domain_list); 43 mutex_unlock(&irq_domain_mutex); 44 } 45 46 /** 47 * irq_domain_del() - Unregister an irq_domain 48 * @domain: ptr to registered irq_domain. 49 */ 50 void irq_domain_del(struct irq_domain *domain) 51 { 52 struct irq_data *d; 53 int hwirq; 54 55 mutex_lock(&irq_domain_mutex); 56 list_del(&domain->list); 57 mutex_unlock(&irq_domain_mutex); 58 59 /* Clear the irq_domain assignments */ 60 for (hwirq = 0; hwirq < domain->nr_irq; hwirq++) { 61 d = irq_get_irq_data(irq_domain_to_irq(domain, hwirq)); 62 d->domain = NULL; 63 } 64 } 65 66 #if defined(CONFIG_OF_IRQ) 67 /** 68 * irq_create_of_mapping() - Map a linux irq number from a DT interrupt spec 69 * 70 * Used by the device tree interrupt mapping code to translate a device tree 71 * interrupt specifier to a valid linux irq number. Returns either a valid 72 * linux IRQ number or 0. 73 * 74 * When the caller no longer need the irq number returned by this function it 75 * should arrange to call irq_dispose_mapping(). 76 */ 77 unsigned int irq_create_of_mapping(struct device_node *controller, 78 const u32 *intspec, unsigned int intsize) 79 { 80 struct irq_domain *domain; 81 unsigned long hwirq; 82 unsigned int irq, type; 83 int rc = -EINVAL; 84 85 /* Find a domain which can translate the irq spec */ 86 mutex_lock(&irq_domain_mutex); 87 list_for_each_entry(domain, &irq_domain_list, list) { 88 if (!domain->ops->dt_translate) 89 continue; 90 rc = domain->ops->dt_translate(domain, controller, 91 intspec, intsize, &hwirq, &type); 92 if (rc == 0) 93 break; 94 } 95 mutex_unlock(&irq_domain_mutex); 96 97 if (rc != 0) 98 return 0; 99 100 irq = irq_domain_to_irq(domain, hwirq); 101 if (type != IRQ_TYPE_NONE) 102 irq_set_irq_type(irq, type); 103 pr_debug("%s: mapped hwirq=%i to irq=%i, flags=%x\n", 104 controller->full_name, (int)hwirq, irq, type); 105 return irq; 106 } 107 EXPORT_SYMBOL_GPL(irq_create_of_mapping); 108 109 /** 110 * irq_dispose_mapping() - Discard a mapping created by irq_create_of_mapping() 111 * @irq: linux irq number to be discarded 112 * 113 * Calling this function indicates the caller no longer needs a reference to 114 * the linux irq number returned by a prior call to irq_create_of_mapping(). 115 */ 116 void irq_dispose_mapping(unsigned int irq) 117 { 118 /* 119 * nothing yet; will be filled when support for dynamic allocation of 120 * irq_descs is added to irq_domain 121 */ 122 } 123 EXPORT_SYMBOL_GPL(irq_dispose_mapping); 124 125 int irq_domain_simple_dt_translate(struct irq_domain *d, 126 struct device_node *controller, 127 const u32 *intspec, unsigned int intsize, 128 unsigned long *out_hwirq, unsigned int *out_type) 129 { 130 if (d->of_node != controller) 131 return -EINVAL; 132 if (intsize < 1) 133 return -EINVAL; 134 135 *out_hwirq = intspec[0]; 136 *out_type = IRQ_TYPE_NONE; 137 if (intsize > 1) 138 *out_type = intspec[1] & IRQ_TYPE_SENSE_MASK; 139 return 0; 140 } 141 142 struct irq_domain_ops irq_domain_simple_ops = { 143 .dt_translate = irq_domain_simple_dt_translate, 144 }; 145 EXPORT_SYMBOL_GPL(irq_domain_simple_ops); 146 147 /** 148 * irq_domain_create_simple() - Set up a 'simple' translation range 149 */ 150 void irq_domain_add_simple(struct device_node *controller, int irq_base) 151 { 152 struct irq_domain *domain; 153 154 domain = kzalloc(sizeof(*domain), GFP_KERNEL); 155 if (!domain) { 156 WARN_ON(1); 157 return; 158 } 159 160 domain->irq_base = irq_base; 161 domain->of_node = of_node_get(controller); 162 domain->ops = &irq_domain_simple_ops; 163 irq_domain_add(domain); 164 } 165 EXPORT_SYMBOL_GPL(irq_domain_add_simple); 166 167 void irq_domain_generate_simple(const struct of_device_id *match, 168 u64 phys_base, unsigned int irq_start) 169 { 170 struct device_node *node; 171 pr_info("looking for phys_base=%llx, irq_start=%i\n", 172 (unsigned long long) phys_base, (int) irq_start); 173 node = of_find_matching_node_by_address(NULL, match, phys_base); 174 if (node) 175 irq_domain_add_simple(node, irq_start); 176 else 177 pr_info("no node found\n"); 178 } 179 EXPORT_SYMBOL_GPL(irq_domain_generate_simple); 180 #endif /* CONFIG_OF_IRQ */ 181