/* * linux/kernel/irq/chip.c * * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar * Copyright (C) 2005-2006, Thomas Gleixner, Russell King * * This file contains the core interrupt handling code, for irq-chip * based architectures. * * Detailed information is available in Documentation/DocBook/genericirq */ #include #include #include #include #include #include "internals.h" static void dynamic_irq_init_x(unsigned int irq, bool keep_chip_data) { struct irq_desc *desc; unsigned long flags; desc = irq_to_desc(irq); if (!desc) { WARN(1, KERN_ERR "Trying to initialize invalid IRQ%d\n", irq); return; } /* Ensure we don't have left over values from a previous use of this irq */ raw_spin_lock_irqsave(&desc->lock, flags); desc->status = IRQ_DISABLED; desc->irq_data.chip = &no_irq_chip; desc->handle_irq = handle_bad_irq; desc->depth = 1; desc->irq_data.msi_desc = NULL; desc->irq_data.handler_data = NULL; if (!keep_chip_data) desc->irq_data.chip_data = NULL; desc->action = NULL; desc->irq_count = 0; desc->irqs_unhandled = 0; #ifdef CONFIG_SMP cpumask_setall(desc->irq_data.affinity); #ifdef CONFIG_GENERIC_PENDING_IRQ cpumask_clear(desc->pending_mask); #endif #endif raw_spin_unlock_irqrestore(&desc->lock, flags); } /** * dynamic_irq_init - initialize a dynamically allocated irq * @irq: irq number to initialize */ void dynamic_irq_init(unsigned int irq) { dynamic_irq_init_x(irq, false); } /** * dynamic_irq_init_keep_chip_data - initialize a dynamically allocated irq * @irq: irq number to initialize * * does not set irq_to_desc(irq)->irq_data.chip_data to NULL */ void dynamic_irq_init_keep_chip_data(unsigned int irq) { dynamic_irq_init_x(irq, true); } static void dynamic_irq_cleanup_x(unsigned int irq, bool keep_chip_data) { struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; if (!desc) { WARN(1, KERN_ERR "Trying to cleanup invalid IRQ%d\n", irq); return; } raw_spin_lock_irqsave(&desc->lock, flags); if (desc->action) { raw_spin_unlock_irqrestore(&desc->lock, flags); WARN(1, KERN_ERR "Destroying IRQ%d without calling free_irq\n", irq); return; } desc->irq_data.msi_desc = NULL; desc->irq_data.handler_data = NULL; if (!keep_chip_data) desc->irq_data.chip_data = NULL; desc->handle_irq = handle_bad_irq; desc->irq_data.chip = &no_irq_chip; desc->name = NULL; clear_kstat_irqs(desc); raw_spin_unlock_irqrestore(&desc->lock, flags); } /** * dynamic_irq_cleanup - cleanup a dynamically allocated irq * @irq: irq number to initialize */ void dynamic_irq_cleanup(unsigned int irq) { dynamic_irq_cleanup_x(irq, false); } /** * dynamic_irq_cleanup_keep_chip_data - cleanup a dynamically allocated irq * @irq: irq number to initialize * * does not set irq_to_desc(irq)->irq_data.chip_data to NULL */ void dynamic_irq_cleanup_keep_chip_data(unsigned int irq) { dynamic_irq_cleanup_x(irq, true); } /** * set_irq_chip - set the irq chip for an irq * @irq: irq number * @chip: pointer to irq chip description structure */ int set_irq_chip(unsigned int irq, struct irq_chip *chip) { struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; if (!desc) { WARN(1, KERN_ERR "Trying to install chip for IRQ%d\n", irq); return -EINVAL; } if (!chip) chip = &no_irq_chip; raw_spin_lock_irqsave(&desc->lock, flags); irq_chip_set_defaults(chip); desc->irq_data.chip = chip; raw_spin_unlock_irqrestore(&desc->lock, flags); return 0; } EXPORT_SYMBOL(set_irq_chip); /** * set_irq_type - set the irq trigger type for an irq * @irq: irq number * @type: IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h */ int set_irq_type(unsigned int irq, unsigned int type) { struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; int ret = -ENXIO; if (!desc) { printk(KERN_ERR "Trying to set irq type for IRQ%d\n", irq); return -ENODEV; } type &= IRQ_TYPE_SENSE_MASK; if (type == IRQ_TYPE_NONE) return 0; raw_spin_lock_irqsave(&desc->lock, flags); ret = __irq_set_trigger(desc, irq, type); raw_spin_unlock_irqrestore(&desc->lock, flags); return ret; } EXPORT_SYMBOL(set_irq_type); /** * set_irq_data - set irq type data for an irq * @irq: Interrupt number * @data: Pointer to interrupt specific data * * Set the hardware irq controller data for an irq */ int set_irq_data(unsigned int irq, void *data) { struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; if (!desc) { printk(KERN_ERR "Trying to install controller data for IRQ%d\n", irq); return -EINVAL; } raw_spin_lock_irqsave(&desc->lock, flags); desc->irq_data.handler_data = data; raw_spin_unlock_irqrestore(&desc->lock, flags); return 0; } EXPORT_SYMBOL(set_irq_data); /** * set_irq_msi - set MSI descriptor data for an irq * @irq: Interrupt number * @entry: Pointer to MSI descriptor data * * Set the MSI descriptor entry for an irq */ int set_irq_msi(unsigned int irq, struct msi_desc *entry) { struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; if (!desc) { printk(KERN_ERR "Trying to install msi data for IRQ%d\n", irq); return -EINVAL; } raw_spin_lock_irqsave(&desc->lock, flags); desc->irq_data.msi_desc = entry; if (entry) entry->irq = irq; raw_spin_unlock_irqrestore(&desc->lock, flags); return 0; } /** * set_irq_chip_data - set irq chip data for an irq * @irq: Interrupt number * @data: Pointer to chip specific data * * Set the hardware irq chip data for an irq */ int set_irq_chip_data(unsigned int irq, void *data) { struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; if (!desc) { printk(KERN_ERR "Trying to install chip data for IRQ%d\n", irq); return -EINVAL; } if (!desc->irq_data.chip) { printk(KERN_ERR "BUG: bad set_irq_chip_data(IRQ#%d)\n", irq); return -EINVAL; } raw_spin_lock_irqsave(&desc->lock, flags); desc->irq_data.chip_data = data; raw_spin_unlock_irqrestore(&desc->lock, flags); return 0; } EXPORT_SYMBOL(set_irq_chip_data); /** * set_irq_nested_thread - Set/Reset the IRQ_NESTED_THREAD flag of an irq * * @irq: Interrupt number * @nest: 0 to clear / 1 to set the IRQ_NESTED_THREAD flag * * The IRQ_NESTED_THREAD flag indicates that on * request_threaded_irq() no separate interrupt thread should be * created for the irq as the handler are called nested in the * context of a demultiplexing interrupt handler thread. */ void set_irq_nested_thread(unsigned int irq, int nest) { struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; if (!desc) return; raw_spin_lock_irqsave(&desc->lock, flags); if (nest) desc->status |= IRQ_NESTED_THREAD; else desc->status &= ~IRQ_NESTED_THREAD; raw_spin_unlock_irqrestore(&desc->lock, flags); } EXPORT_SYMBOL_GPL(set_irq_nested_thread); /* * default enable function */ static void default_enable(struct irq_data *data) { struct irq_desc *desc = irq_data_to_desc(data); desc->irq_data.chip->irq_unmask(&desc->irq_data); desc->status &= ~IRQ_MASKED; } /* * default disable function */ static void default_disable(struct irq_data *data) { } /* * default startup function */ static unsigned int default_startup(struct irq_data *data) { struct irq_desc *desc = irq_data_to_desc(data); desc->irq_data.chip->irq_enable(data); return 0; } /* * default shutdown function */ static void default_shutdown(struct irq_data *data) { struct irq_desc *desc = irq_data_to_desc(data); desc->irq_data.chip->irq_mask(&desc->irq_data); desc->status |= IRQ_MASKED; } /* Temporary migration helpers */ static void compat_irq_mask(struct irq_data *data) { data->chip->mask(data->irq); } static void compat_irq_unmask(struct irq_data *data) { data->chip->unmask(data->irq); } static void compat_irq_ack(struct irq_data *data) { data->chip->ack(data->irq); } static void compat_irq_mask_ack(struct irq_data *data) { data->chip->mask_ack(data->irq); } static void compat_irq_eoi(struct irq_data *data) { data->chip->eoi(data->irq); } static void compat_irq_enable(struct irq_data *data) { data->chip->enable(data->irq); } static void compat_irq_disable(struct irq_data *data) { data->chip->disable(data->irq); } static void compat_irq_shutdown(struct irq_data *data) { data->chip->shutdown(data->irq); } static unsigned int compat_irq_startup(struct irq_data *data) { return data->chip->startup(data->irq); } static void compat_bus_lock(struct irq_data *data) { data->chip->bus_lock(data->irq); } static void compat_bus_sync_unlock(struct irq_data *data) { data->chip->bus_sync_unlock(data->irq); } /* * Fixup enable/disable function pointers */ void irq_chip_set_defaults(struct irq_chip *chip) { /* * Compat fixup functions need to be before we set the * defaults for enable/disable/startup/shutdown */ if (chip->enable) chip->irq_enable = compat_irq_enable; if (chip->disable) chip->irq_disable = compat_irq_disable; if (chip->shutdown) chip->irq_shutdown = compat_irq_shutdown; if (chip->startup) chip->irq_startup = compat_irq_startup; /* * The real defaults */ if (!chip->irq_enable) chip->irq_enable = default_enable; if (!chip->irq_disable) chip->irq_disable = default_disable; if (!chip->irq_startup) chip->irq_startup = default_startup; /* * We use chip->irq_disable, when the user provided its own. When * we have default_disable set for chip->irq_disable, then we need * to use default_shutdown, otherwise the irq line is not * disabled on free_irq(): */ if (!chip->irq_shutdown) chip->irq_shutdown = chip->irq_disable != default_disable ? chip->irq_disable : default_shutdown; if (!chip->end) chip->end = dummy_irq_chip.end; /* * Now fix up the remaining compat handlers */ if (chip->bus_lock) chip->irq_bus_lock = compat_bus_lock; if (chip->bus_sync_unlock) chip->irq_bus_sync_unlock = compat_bus_sync_unlock; if (chip->mask) chip->irq_mask = compat_irq_mask; if (chip->unmask) chip->irq_unmask = compat_irq_unmask; if (chip->ack) chip->irq_ack = compat_irq_ack; if (chip->mask_ack) chip->irq_mask_ack = compat_irq_mask_ack; if (chip->eoi) chip->irq_eoi = compat_irq_eoi; } static inline void mask_ack_irq(struct irq_desc *desc) { if (desc->irq_data.chip->irq_mask_ack) desc->irq_data.chip->irq_mask_ack(&desc->irq_data); else { desc->irq_data.chip->irq_mask(&desc->irq_data); if (desc->irq_data.chip->irq_ack) desc->irq_data.chip->irq_ack(&desc->irq_data); } desc->status |= IRQ_MASKED; } static inline void mask_irq(struct irq_desc *desc) { if (desc->irq_data.chip->irq_mask) { desc->irq_data.chip->irq_mask(&desc->irq_data); desc->status |= IRQ_MASKED; } } static inline void unmask_irq(struct irq_desc *desc) { if (desc->irq_data.chip->irq_unmask) { desc->irq_data.chip->irq_unmask(&desc->irq_data); desc->status &= ~IRQ_MASKED; } } /* * handle_nested_irq - Handle a nested irq from a irq thread * @irq: the interrupt number * * Handle interrupts which are nested into a threaded interrupt * handler. The handler function is called inside the calling * threads context. */ void handle_nested_irq(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); struct irqaction *action; irqreturn_t action_ret; might_sleep(); raw_spin_lock_irq(&desc->lock); kstat_incr_irqs_this_cpu(irq, desc); action = desc->action; if (unlikely(!action || (desc->status & IRQ_DISABLED))) goto out_unlock; desc->status |= IRQ_INPROGRESS; raw_spin_unlock_irq(&desc->lock); action_ret = action->thread_fn(action->irq, action->dev_id); if (!noirqdebug) note_interrupt(irq, desc, action_ret); raw_spin_lock_irq(&desc->lock); desc->status &= ~IRQ_INPROGRESS; out_unlock: raw_spin_unlock_irq(&desc->lock); } EXPORT_SYMBOL_GPL(handle_nested_irq); /** * handle_simple_irq - Simple and software-decoded IRQs. * @irq: the interrupt number * @desc: the interrupt description structure for this irq * * Simple interrupts are either sent from a demultiplexing interrupt * handler or come from hardware, where no interrupt hardware control * is necessary. * * Note: The caller is expected to handle the ack, clear, mask and * unmask issues if necessary. */ void handle_simple_irq(unsigned int irq, struct irq_desc *desc) { struct irqaction *action; irqreturn_t action_ret; raw_spin_lock(&desc->lock); if (unlikely(desc->status & IRQ_INPROGRESS)) goto out_unlock; desc->status &= ~(IRQ_REPLAY | IRQ_WAITING); kstat_incr_irqs_this_cpu(irq, desc); action = desc->action; if (unlikely(!action || (desc->status & IRQ_DISABLED))) goto out_unlock; desc->status |= IRQ_INPROGRESS; raw_spin_unlock(&desc->lock); action_ret = handle_IRQ_event(irq, action); if (!noirqdebug) note_interrupt(irq, desc, action_ret); raw_spin_lock(&desc->lock); desc->status &= ~IRQ_INPROGRESS; out_unlock: raw_spin_unlock(&desc->lock); } /** * handle_level_irq - Level type irq handler * @irq: the interrupt number * @desc: the interrupt description structure for this irq * * Level type interrupts are active as long as the hardware line has * the active level. This may require to mask the interrupt and unmask * it after the associated handler has acknowledged the device, so the * interrupt line is back to inactive. */ void handle_level_irq(unsigned int irq, struct irq_desc *desc) { struct irqaction *action; irqreturn_t action_ret; raw_spin_lock(&desc->lock); mask_ack_irq(desc); if (unlikely(desc->status & IRQ_INPROGRESS)) goto out_unlock; desc->status &= ~(IRQ_REPLAY | IRQ_WAITING); kstat_incr_irqs_this_cpu(irq, desc); /* * If its disabled or no action available * keep it masked and get out of here */ action = desc->action; if (unlikely(!action || (desc->status & IRQ_DISABLED))) goto out_unlock; desc->status |= IRQ_INPROGRESS; raw_spin_unlock(&desc->lock); action_ret = handle_IRQ_event(irq, action); if (!noirqdebug) note_interrupt(irq, desc, action_ret); raw_spin_lock(&desc->lock); desc->status &= ~IRQ_INPROGRESS; if (!(desc->status & (IRQ_DISABLED | IRQ_ONESHOT))) unmask_irq(desc); out_unlock: raw_spin_unlock(&desc->lock); } EXPORT_SYMBOL_GPL(handle_level_irq); /** * handle_fasteoi_irq - irq handler for transparent controllers * @irq: the interrupt number * @desc: the interrupt description structure for this irq * * Only a single callback will be issued to the chip: an ->eoi() * call when the interrupt has been serviced. This enables support * for modern forms of interrupt handlers, which handle the flow * details in hardware, transparently. */ void handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc) { struct irqaction *action; irqreturn_t action_ret; raw_spin_lock(&desc->lock); if (unlikely(desc->status & IRQ_INPROGRESS)) goto out; desc->status &= ~(IRQ_REPLAY | IRQ_WAITING); kstat_incr_irqs_this_cpu(irq, desc); /* * If its disabled or no action available * then mask it and get out of here: */ action = desc->action; if (unlikely(!action || (desc->status & IRQ_DISABLED))) { desc->status |= IRQ_PENDING; mask_irq(desc); goto out; } desc->status |= IRQ_INPROGRESS; desc->status &= ~IRQ_PENDING; raw_spin_unlock(&desc->lock); action_ret = handle_IRQ_event(irq, action); if (!noirqdebug) note_interrupt(irq, desc, action_ret); raw_spin_lock(&desc->lock); desc->status &= ~IRQ_INPROGRESS; out: desc->irq_data.chip->irq_eoi(&desc->irq_data); raw_spin_unlock(&desc->lock); } /** * handle_edge_irq - edge type IRQ handler * @irq: the interrupt number * @desc: the interrupt description structure for this irq * * Interrupt occures on the falling and/or rising edge of a hardware * signal. The occurence is latched into the irq controller hardware * and must be acked in order to be reenabled. After the ack another * interrupt can happen on the same source even before the first one * is handled by the associated event handler. If this happens it * might be necessary to disable (mask) the interrupt depending on the * controller hardware. This requires to reenable the interrupt inside * of the loop which handles the interrupts which have arrived while * the handler was running. If all pending interrupts are handled, the * loop is left. */ void handle_edge_irq(unsigned int irq, struct irq_desc *desc) { raw_spin_lock(&desc->lock); desc->status &= ~(IRQ_REPLAY | IRQ_WAITING); /* * If we're currently running this IRQ, or its disabled, * we shouldn't process the IRQ. Mark it pending, handle * the necessary masking and go out */ if (unlikely((desc->status & (IRQ_INPROGRESS | IRQ_DISABLED)) || !desc->action)) { desc->status |= (IRQ_PENDING | IRQ_MASKED); mask_ack_irq(desc); goto out_unlock; } kstat_incr_irqs_this_cpu(irq, desc); /* Start handling the irq */ desc->irq_data.chip->irq_ack(&desc->irq_data); /* Mark the IRQ currently in progress.*/ desc->status |= IRQ_INPROGRESS; do { struct irqaction *action = desc->action; irqreturn_t action_ret; if (unlikely(!action)) { mask_irq(desc); goto out_unlock; } /* * When another irq arrived while we were handling * one, we could have masked the irq. * Renable it, if it was not disabled in meantime. */ if (unlikely((desc->status & (IRQ_PENDING | IRQ_MASKED | IRQ_DISABLED)) == (IRQ_PENDING | IRQ_MASKED))) { unmask_irq(desc); } desc->status &= ~IRQ_PENDING; raw_spin_unlock(&desc->lock); action_ret = handle_IRQ_event(irq, action); if (!noirqdebug) note_interrupt(irq, desc, action_ret); raw_spin_lock(&desc->lock); } while ((desc->status & (IRQ_PENDING | IRQ_DISABLED)) == IRQ_PENDING); desc->status &= ~IRQ_INPROGRESS; out_unlock: raw_spin_unlock(&desc->lock); } /** * handle_percpu_irq - Per CPU local irq handler * @irq: the interrupt number * @desc: the interrupt description structure for this irq * * Per CPU interrupts on SMP machines without locking requirements */ void handle_percpu_irq(unsigned int irq, struct irq_desc *desc) { irqreturn_t action_ret; kstat_incr_irqs_this_cpu(irq, desc); if (desc->irq_data.chip->irq_ack) desc->irq_data.chip->irq_ack(&desc->irq_data); action_ret = handle_IRQ_event(irq, desc->action); if (!noirqdebug) note_interrupt(irq, desc, action_ret); if (desc->irq_data.chip->irq_eoi) desc->irq_data.chip->irq_eoi(&desc->irq_data); } void __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained, const char *name) { struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; if (!desc) { printk(KERN_ERR "Trying to install type control for IRQ%d\n", irq); return; } if (!handle) handle = handle_bad_irq; else if (desc->irq_data.chip == &no_irq_chip) { printk(KERN_WARNING "Trying to install %sinterrupt handler " "for IRQ%d\n", is_chained ? "chained " : "", irq); /* * Some ARM implementations install a handler for really dumb * interrupt hardware without setting an irq_chip. This worked * with the ARM no_irq_chip but the check in setup_irq would * prevent us to setup the interrupt at all. Switch it to * dummy_irq_chip for easy transition. */ desc->irq_data.chip = &dummy_irq_chip; } chip_bus_lock(desc); raw_spin_lock_irqsave(&desc->lock, flags); /* Uninstall? */ if (handle == handle_bad_irq) { if (desc->irq_data.chip != &no_irq_chip) mask_ack_irq(desc); desc->status |= IRQ_DISABLED; desc->depth = 1; } desc->handle_irq = handle; desc->name = name; if (handle != handle_bad_irq && is_chained) { desc->status &= ~IRQ_DISABLED; desc->status |= IRQ_NOREQUEST | IRQ_NOPROBE; desc->depth = 0; desc->irq_data.chip->irq_startup(&desc->irq_data); } raw_spin_unlock_irqrestore(&desc->lock, flags); chip_bus_sync_unlock(desc); } EXPORT_SYMBOL_GPL(__set_irq_handler); void set_irq_chip_and_handler(unsigned int irq, struct irq_chip *chip, irq_flow_handler_t handle) { set_irq_chip(irq, chip); __set_irq_handler(irq, handle, 0, NULL); } void set_irq_chip_and_handler_name(unsigned int irq, struct irq_chip *chip, irq_flow_handler_t handle, const char *name) { set_irq_chip(irq, chip); __set_irq_handler(irq, handle, 0, name); } void set_irq_noprobe(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; if (!desc) { printk(KERN_ERR "Trying to mark IRQ%d non-probeable\n", irq); return; } raw_spin_lock_irqsave(&desc->lock, flags); desc->status |= IRQ_NOPROBE; raw_spin_unlock_irqrestore(&desc->lock, flags); } void set_irq_probe(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); unsigned long flags; if (!desc) { printk(KERN_ERR "Trying to mark IRQ%d probeable\n", irq); return; } raw_spin_lock_irqsave(&desc->lock, flags); desc->status &= ~IRQ_NOPROBE; raw_spin_unlock_irqrestore(&desc->lock, flags); }