Merge branch 'irq/for-block' into irq/core
[cascardo/linux.git] / kernel / irq / irqdesc.c
index 5a5a685..00bb0ae 100644 (file)
@@ -15,6 +15,7 @@
 #include <linux/radix-tree.h>
 #include <linux/bitmap.h>
 #include <linux/irqdomain.h>
+#include <linux/sysfs.h>
 
 #include "internals.h"
 
@@ -123,6 +124,181 @@ static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS);
 
 #ifdef CONFIG_SPARSE_IRQ
 
+static void irq_kobj_release(struct kobject *kobj);
+
+#ifdef CONFIG_SYSFS
+static struct kobject *irq_kobj_base;
+
+#define IRQ_ATTR_RO(_name) \
+static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
+
+static ssize_t per_cpu_count_show(struct kobject *kobj,
+                                 struct kobj_attribute *attr, char *buf)
+{
+       struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
+       int cpu, irq = desc->irq_data.irq;
+       ssize_t ret = 0;
+       char *p = "";
+
+       for_each_possible_cpu(cpu) {
+               unsigned int c = kstat_irqs_cpu(irq, cpu);
+
+               ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c);
+               p = ",";
+       }
+
+       ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
+       return ret;
+}
+IRQ_ATTR_RO(per_cpu_count);
+
+static ssize_t chip_name_show(struct kobject *kobj,
+                             struct kobj_attribute *attr, char *buf)
+{
+       struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
+       ssize_t ret = 0;
+
+       raw_spin_lock_irq(&desc->lock);
+       if (desc->irq_data.chip && desc->irq_data.chip->name) {
+               ret = scnprintf(buf, PAGE_SIZE, "%s\n",
+                               desc->irq_data.chip->name);
+       }
+       raw_spin_unlock_irq(&desc->lock);
+
+       return ret;
+}
+IRQ_ATTR_RO(chip_name);
+
+static ssize_t hwirq_show(struct kobject *kobj,
+                         struct kobj_attribute *attr, char *buf)
+{
+       struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
+       ssize_t ret = 0;
+
+       raw_spin_lock_irq(&desc->lock);
+       if (desc->irq_data.domain)
+               ret = sprintf(buf, "%d\n", (int)desc->irq_data.hwirq);
+       raw_spin_unlock_irq(&desc->lock);
+
+       return ret;
+}
+IRQ_ATTR_RO(hwirq);
+
+static ssize_t type_show(struct kobject *kobj,
+                        struct kobj_attribute *attr, char *buf)
+{
+       struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
+       ssize_t ret = 0;
+
+       raw_spin_lock_irq(&desc->lock);
+       ret = sprintf(buf, "%s\n",
+                     irqd_is_level_type(&desc->irq_data) ? "level" : "edge");
+       raw_spin_unlock_irq(&desc->lock);
+
+       return ret;
+
+}
+IRQ_ATTR_RO(type);
+
+static ssize_t name_show(struct kobject *kobj,
+                        struct kobj_attribute *attr, char *buf)
+{
+       struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
+       ssize_t ret = 0;
+
+       raw_spin_lock_irq(&desc->lock);
+       if (desc->name)
+               ret = scnprintf(buf, PAGE_SIZE, "%s\n", desc->name);
+       raw_spin_unlock_irq(&desc->lock);
+
+       return ret;
+}
+IRQ_ATTR_RO(name);
+
+static ssize_t actions_show(struct kobject *kobj,
+                           struct kobj_attribute *attr, char *buf)
+{
+       struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
+       struct irqaction *action;
+       ssize_t ret = 0;
+       char *p = "";
+
+       raw_spin_lock_irq(&desc->lock);
+       for (action = desc->action; action != NULL; action = action->next) {
+               ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%s",
+                                p, action->name);
+               p = ",";
+       }
+       raw_spin_unlock_irq(&desc->lock);
+
+       if (ret)
+               ret += scnprintf(buf + ret, PAGE_SIZE - ret, "\n");
+
+       return ret;
+}
+IRQ_ATTR_RO(actions);
+
+static struct attribute *irq_attrs[] = {
+       &per_cpu_count_attr.attr,
+       &chip_name_attr.attr,
+       &hwirq_attr.attr,
+       &type_attr.attr,
+       &name_attr.attr,
+       &actions_attr.attr,
+       NULL
+};
+
+static struct kobj_type irq_kobj_type = {
+       .release        = irq_kobj_release,
+       .sysfs_ops      = &kobj_sysfs_ops,
+       .default_attrs  = irq_attrs,
+};
+
+static void irq_sysfs_add(int irq, struct irq_desc *desc)
+{
+       if (irq_kobj_base) {
+               /*
+                * Continue even in case of failure as this is nothing
+                * crucial.
+                */
+               if (kobject_add(&desc->kobj, irq_kobj_base, "%d", irq))
+                       pr_warn("Failed to add kobject for irq %d\n", irq);
+       }
+}
+
+static int __init irq_sysfs_init(void)
+{
+       struct irq_desc *desc;
+       int irq;
+
+       /* Prevent concurrent irq alloc/free */
+       irq_lock_sparse();
+
+       irq_kobj_base = kobject_create_and_add("irq", kernel_kobj);
+       if (!irq_kobj_base) {
+               irq_unlock_sparse();
+               return -ENOMEM;
+       }
+
+       /* Add the already allocated interrupts */
+       for_each_irq_desc(irq, desc)
+               irq_sysfs_add(irq, desc);
+       irq_unlock_sparse();
+
+       return 0;
+}
+postcore_initcall(irq_sysfs_init);
+
+#else /* !CONFIG_SYSFS */
+
+static struct kobj_type irq_kobj_type = {
+       .release        = irq_kobj_release,
+};
+
+static void irq_sysfs_add(int irq, struct irq_desc *desc) {}
+
+#endif /* CONFIG_SYSFS */
+
 static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
 
 static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
@@ -187,6 +363,7 @@ static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
 
        desc_set_defaults(irq, desc, node, affinity, owner);
        irqd_set(&desc->irq_data, flags);
+       kobject_init(&desc->kobj, &irq_kobj_type);
 
        return desc;
 
@@ -197,15 +374,22 @@ err_desc:
        return NULL;
 }
 
-static void delayed_free_desc(struct rcu_head *rhp)
+static void irq_kobj_release(struct kobject *kobj)
 {
-       struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
+       struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj);
 
        free_masks(desc);
        free_percpu(desc->kstat_irqs);
        kfree(desc);
 }
 
+static void delayed_free_desc(struct rcu_head *rhp)
+{
+       struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
+
+       kobject_put(&desc->kobj);
+}
+
 static void free_desc(unsigned int irq)
 {
        struct irq_desc *desc = irq_to_desc(irq);
@@ -217,8 +401,12 @@ static void free_desc(unsigned int irq)
         * kstat_irq_usr(). Once we deleted the descriptor from the
         * sparse tree we can free it. Access in proc will fail to
         * lookup the descriptor.
+        *
+        * The sysfs entry must be serialized against a concurrent
+        * irq_sysfs_init() as well.
         */
        mutex_lock(&sparse_irq_lock);
+       kobject_del(&desc->kobj);
        delete_irq_desc(irq);
        mutex_unlock(&sparse_irq_lock);
 
@@ -260,6 +448,7 @@ static int alloc_descs(unsigned int start, unsigned int cnt, int node,
                        goto err;
                mutex_lock(&sparse_irq_lock);
                irq_insert_desc(start + i, desc);
+               irq_sysfs_add(start + i, desc);
                mutex_unlock(&sparse_irq_lock);
        }
        return start;