From be45beb2df6909d42a6b3b0052601b3eef878fc0 Mon Sep 17 00:00:00 2001 From: Jon Hunter Date: Tue, 7 Jun 2016 16:12:29 +0100 Subject: [PATCH] genirq: Add runtime power management support for IRQ chips Some IRQ chips may be located in a power domain outside of the CPU subsystem and hence will require device specific runtime power management. In order to support such IRQ chips, add a pointer for a device structure to the irq_chip structure, and if this pointer is populated by the IRQ chip driver and CONFIG_PM is selected in the kernel configuration, then the pm_runtime_get/put APIs for this chip will be called when an IRQ is requested/freed, respectively. Reviewed-by: Kevin Hilman Signed-off-by: Jon Hunter Signed-off-by: Marc Zyngier --- include/linux/irq.h | 4 ++++ kernel/irq/chip.c | 40 ++++++++++++++++++++++++++++++++++++++++ kernel/irq/internals.h | 1 + kernel/irq/manage.c | 31 ++++++++++++++++++++++++++++++- 4 files changed, 75 insertions(+), 1 deletion(-) diff --git a/include/linux/irq.h b/include/linux/irq.h index 4d758a7c604a..6c92a847394d 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -315,6 +315,7 @@ static inline irq_hw_number_t irqd_to_hwirq(struct irq_data *d) /** * struct irq_chip - hardware interrupt chip descriptor * + * @parent_device: pointer to parent device for irqchip * @name: name for /proc/interrupts * @irq_startup: start up the interrupt (defaults to ->enable if NULL) * @irq_shutdown: shut down the interrupt (defaults to ->disable if NULL) @@ -354,6 +355,7 @@ static inline irq_hw_number_t irqd_to_hwirq(struct irq_data *d) * @flags: chip specific flags */ struct irq_chip { + struct device *parent_device; const char *name; unsigned int (*irq_startup)(struct irq_data *data); void (*irq_shutdown)(struct irq_data *data); @@ -488,6 +490,8 @@ extern void handle_bad_irq(struct irq_desc *desc); extern void handle_nested_irq(unsigned int irq); extern int irq_chip_compose_msi_msg(struct irq_data *data, struct msi_msg *msg); +extern int irq_chip_pm_get(struct irq_data *data); +extern int irq_chip_pm_put(struct irq_data *data); #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY extern void irq_chip_enable_parent(struct irq_data *data); extern void irq_chip_disable_parent(struct irq_data *data); diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 2f9f2b0e79f2..ad8131473774 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -1093,3 +1093,43 @@ int irq_chip_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) return 0; } + +/** + * irq_chip_pm_get - Enable power for an IRQ chip + * @data: Pointer to interrupt specific data + * + * Enable the power to the IRQ chip referenced by the interrupt data + * structure. + */ +int irq_chip_pm_get(struct irq_data *data) +{ + int retval; + + if (IS_ENABLED(CONFIG_PM) && data->chip->parent_device) { + retval = pm_runtime_get_sync(data->chip->parent_device); + if (retval < 0) { + pm_runtime_put_noidle(data->chip->parent_device); + return retval; + } + } + + return 0; +} + +/** + * irq_chip_pm_put - Disable power for an IRQ chip + * @data: Pointer to interrupt specific data + * + * Disable the power to the IRQ chip referenced by the interrupt data + * structure, belongs. Note that power will only be disabled, once this + * function has been called for all IRQs that have called irq_chip_pm_get(). + */ +int irq_chip_pm_put(struct irq_data *data) +{ + int retval = 0; + + if (IS_ENABLED(CONFIG_PM) && data->chip->parent_device) + retval = pm_runtime_put(data->chip->parent_device); + + return (retval < 0) ? retval : 0; +} diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index 09be2c903c6d..d5edcdc9382a 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -7,6 +7,7 @@ */ #include #include +#include #ifdef CONFIG_SPARSE_IRQ # define IRQ_BITMAP_BITS (NR_IRQS + 8196) diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index f78b0846afb1..00cfc852cca8 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -1416,10 +1416,18 @@ int setup_irq(unsigned int irq, struct irqaction *act) if (!desc || WARN_ON(irq_settings_is_per_cpu_devid(desc))) return -EINVAL; + + retval = irq_chip_pm_get(&desc->irq_data); + if (retval < 0) + return retval; + chip_bus_lock(desc); retval = __setup_irq(irq, desc, act); chip_bus_sync_unlock(desc); + if (retval) + irq_chip_pm_put(&desc->irq_data); + return retval; } EXPORT_SYMBOL_GPL(setup_irq); @@ -1513,6 +1521,7 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id) } } + irq_chip_pm_put(&desc->irq_data); module_put(desc->owner); kfree(action->secondary); return action; @@ -1655,11 +1664,16 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler, action->name = devname; action->dev_id = dev_id; + retval = irq_chip_pm_get(&desc->irq_data); + if (retval < 0) + return retval; + chip_bus_lock(desc); retval = __setup_irq(irq, desc, action); chip_bus_sync_unlock(desc); if (retval) { + irq_chip_pm_put(&desc->irq_data); kfree(action->secondary); kfree(action); } @@ -1836,6 +1850,7 @@ static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_ unregister_handler_proc(irq, action); + irq_chip_pm_put(&desc->irq_data); module_put(desc->owner); return action; @@ -1898,10 +1913,18 @@ int setup_percpu_irq(unsigned int irq, struct irqaction *act) if (!desc || !irq_settings_is_per_cpu_devid(desc)) return -EINVAL; + + retval = irq_chip_pm_get(&desc->irq_data); + if (retval < 0) + return retval; + chip_bus_lock(desc); retval = __setup_irq(irq, desc, act); chip_bus_sync_unlock(desc); + if (retval) + irq_chip_pm_put(&desc->irq_data); + return retval; } @@ -1945,12 +1968,18 @@ int request_percpu_irq(unsigned int irq, irq_handler_t handler, action->name = devname; action->percpu_dev_id = dev_id; + retval = irq_chip_pm_get(&desc->irq_data); + if (retval < 0) + return retval; + chip_bus_lock(desc); retval = __setup_irq(irq, desc, action); chip_bus_sync_unlock(desc); - if (retval) + if (retval) { + irq_chip_pm_put(&desc->irq_data); kfree(action); + } return retval; } -- 2.20.1