diff options
| -rw-r--r-- | include/linux/irq.h | 6 | ||||
| -rw-r--r-- | kernel/irq/chip.c | 2 | ||||
| -rw-r--r-- | kernel/irq/internals.h | 13 | ||||
| -rw-r--r-- | kernel/irq/manage.c | 19 |
4 files changed, 39 insertions, 1 deletions
diff --git a/include/linux/irq.h b/include/linux/irq.h index 5e7c6ee8c35c..ce8171bc6fac 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -101,6 +101,9 @@ struct msi_desc; * @set_type: set the flow type (IRQ_TYPE_LEVEL/etc.) of an IRQ * @set_wake: enable/disable power-management wake-on of an IRQ * + * @bus_lock: function to lock access to slow bus (i2c) chips + * @bus_sync_unlock: function to sync and unlock slow bus (i2c) chips + * * @release: release function solely used by UML * @typename: obsoleted by name, kept as migration helper */ @@ -124,6 +127,9 @@ struct irq_chip { int (*set_type)(unsigned int irq, unsigned int flow_type); int (*set_wake)(unsigned int irq, unsigned int on); + void (*bus_lock)(unsigned int irq); + void (*bus_sync_unlock)(unsigned int irq); + /* Currently used only by UML, might disappear one day.*/ #ifdef CONFIG_IRQ_RELEASE_METHOD void (*release)(unsigned int irq, void *dev_id); diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index b08c0d24f202..f856330e684a 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -580,6 +580,7 @@ __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained, desc->chip = &dummy_irq_chip; } + chip_bus_lock(irq, desc); spin_lock_irqsave(&desc->lock, flags); /* Uninstall? */ @@ -599,6 +600,7 @@ __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained, desc->chip->startup(irq); } spin_unlock_irqrestore(&desc->lock, flags); + chip_bus_sync_unlock(irq, desc); } EXPORT_SYMBOL_GPL(__set_irq_handler); diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index e70ed5592eb9..1b5d742c6a77 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -44,6 +44,19 @@ extern int irq_select_affinity_usr(unsigned int irq); extern void irq_set_thread_affinity(struct irq_desc *desc); +/* Inline functions for support of irq chips on slow busses */ +static inline void chip_bus_lock(unsigned int irq, struct irq_desc *desc) +{ + if (unlikely(desc->chip->bus_lock)) + desc->chip->bus_lock(irq); +} + +static inline void chip_bus_sync_unlock(unsigned int irq, struct irq_desc *desc) +{ + if (unlikely(desc->chip->bus_sync_unlock)) + desc->chip->bus_sync_unlock(irq); +} + /* * Debugging printout: */ diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index d7f7b5fd2476..0a3fd5b524c9 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -230,9 +230,11 @@ void disable_irq_nosync(unsigned int irq) if (!desc) return; + chip_bus_lock(irq, desc); spin_lock_irqsave(&desc->lock, flags); __disable_irq(desc, irq, false); spin_unlock_irqrestore(&desc->lock, flags); + chip_bus_sync_unlock(irq, desc); } EXPORT_SYMBOL(disable_irq_nosync); @@ -294,7 +296,8 @@ void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume) * matches the last disable, processing of interrupts on this * IRQ line is re-enabled. * - * This function may be called from IRQ context. + * This function may be called from IRQ context only when + * desc->chip->bus_lock and desc->chip->bus_sync_unlock are NULL ! */ void enable_irq(unsigned int irq) { @@ -304,9 +307,11 @@ void enable_irq(unsigned int irq) if (!desc) return; + chip_bus_lock(irq, desc); spin_lock_irqsave(&desc->lock, flags); __enable_irq(desc, irq, false); spin_unlock_irqrestore(&desc->lock, flags); + chip_bus_sync_unlock(irq, desc); } EXPORT_SYMBOL(enable_irq); @@ -468,12 +473,14 @@ static int irq_wait_for_interrupt(struct irqaction *action) */ static void irq_finalize_oneshot(unsigned int irq, struct irq_desc *desc) { + chip_bus_lock(irq, desc); spin_lock_irq(&desc->lock); if (!(desc->status & IRQ_DISABLED) && (desc->status & IRQ_MASKED)) { desc->status &= ~IRQ_MASKED; desc->chip->unmask(irq); } spin_unlock_irq(&desc->lock); + chip_bus_sync_unlock(irq, desc); } #ifdef CONFIG_SMP @@ -904,7 +911,14 @@ EXPORT_SYMBOL_GPL(remove_irq); */ void free_irq(unsigned int irq, void *dev_id) { + struct irq_desc *desc = irq_to_desc(irq); + + if (!desc) + return; + + chip_bus_lock(irq, desc); kfree(__free_irq(irq, dev_id)); + chip_bus_sync_unlock(irq, desc); } EXPORT_SYMBOL(free_irq); @@ -1011,7 +1025,10 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler, action->name = devname; action->dev_id = dev_id; + chip_bus_lock(irq, desc); retval = __setup_irq(irq, desc, action); + chip_bus_sync_unlock(irq, desc); + if (retval) kfree(action); |