From bed570307ed78f21b77cb04a1df781dee4a8f05a Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Mon, 5 Dec 2016 16:38:16 -0800 Subject: [PATCH] PM / wakeirq: Fix dedicated wakeirq for drivers not using autosuspend I noticed some wakeirq flakeyness with consumer drivers not using autosuspend. For drivers not using autosuspend, the wakeirq may never get unmasked in rpm_suspend() because of irq desc->depth. We are configuring dedicated wakeirqs to start with IRQ_NOAUTOEN as we naturally don't want them running until rpm_suspend() is called. However, when a consumer driver initially calls pm_runtime_get(), we now wrongly start with disable_irq_nosync() call on the dedicated wakeirq that is disabled to start with. This causes desc->depth to toggle between 1 and 2 instead of the usual 0 and 1. This can prevent enable_irq() from unmasking the wakeirq as that only happens at desc->depth 1. This does not necessarily show up with drivers using autosuspend as there is time for disable_irq_nosync() before rpm_suspend() gets called after the autosuspend timeout. Let's fix the issue by adding wirq->status that lazily gets set on the first rpm_suspend(). We also need PM runtime core private functions for dev_pm_enable_wake_irq_check() and dev_pm_disable_wake_irq_check() so we can enable the dedicated wakeirq on the first rpm_suspend(). While at it, let's also fix the comments for dev_pm_enable_wake_irq() and dev_pm_disable_wake_irq(). Those can still be used by the consumer drivers as needed because the IRQ core manages the interrupt usecount for us. Fixes: 4990d4fe327b (PM / Wakeirq: Add automated device wake IRQ handling) Signed-off-by: Tony Lindgren Signed-off-by: Rafael J. Wysocki --- drivers/base/power/power.h | 19 ++++++++- drivers/base/power/runtime.c | 8 ++-- drivers/base/power/wakeirq.c | 76 +++++++++++++++++++++++++++++++----- 3 files changed, 88 insertions(+), 15 deletions(-) diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h index 50e30e7b059d..a84332aefc2d 100644 --- a/drivers/base/power/power.h +++ b/drivers/base/power/power.h @@ -21,14 +21,22 @@ extern void pm_runtime_init(struct device *dev); extern void pm_runtime_reinit(struct device *dev); extern void pm_runtime_remove(struct device *dev); +#define WAKE_IRQ_DEDICATED_ALLOCATED BIT(0) +#define WAKE_IRQ_DEDICATED_MANAGED BIT(1) +#define WAKE_IRQ_DEDICATED_MASK (WAKE_IRQ_DEDICATED_ALLOCATED | \ + WAKE_IRQ_DEDICATED_MANAGED) + struct wake_irq { struct device *dev; + unsigned int status; int irq; - bool dedicated_irq:1; }; extern void dev_pm_arm_wake_irq(struct wake_irq *wirq); extern void dev_pm_disarm_wake_irq(struct wake_irq *wirq); +extern void dev_pm_enable_wake_irq_check(struct device *dev, + bool can_change_status); +extern void dev_pm_disable_wake_irq_check(struct device *dev); #ifdef CONFIG_PM_SLEEP @@ -104,6 +112,15 @@ static inline void dev_pm_disarm_wake_irq(struct wake_irq *wirq) { } +static inline void dev_pm_enable_wake_irq_check(struct device *dev, + bool can_change_status) +{ +} + +static inline void dev_pm_disable_wake_irq_check(struct device *dev) +{ +} + #endif #ifdef CONFIG_PM_SLEEP diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index f0d863089345..26856d050037 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -516,7 +516,7 @@ static int rpm_suspend(struct device *dev, int rpmflags) callback = RPM_GET_CALLBACK(dev, runtime_suspend); - dev_pm_enable_wake_irq(dev); + dev_pm_enable_wake_irq_check(dev, true); retval = rpm_callback(callback, dev); if (retval) goto fail; @@ -555,7 +555,7 @@ static int rpm_suspend(struct device *dev, int rpmflags) return retval; fail: - dev_pm_disable_wake_irq(dev); + dev_pm_disable_wake_irq_check(dev); __update_runtime_status(dev, RPM_ACTIVE); dev->power.deferred_resume = false; wake_up_all(&dev->power.wait_queue); @@ -738,12 +738,12 @@ static int rpm_resume(struct device *dev, int rpmflags) callback = RPM_GET_CALLBACK(dev, runtime_resume); - dev_pm_disable_wake_irq(dev); + dev_pm_disable_wake_irq_check(dev); retval = rpm_callback(callback, dev); if (retval) { __update_runtime_status(dev, RPM_SUSPENDED); pm_runtime_cancel_pending(dev); - dev_pm_enable_wake_irq(dev); + dev_pm_enable_wake_irq_check(dev, false); } else { no_callback: __update_runtime_status(dev, RPM_ACTIVE); diff --git a/drivers/base/power/wakeirq.c b/drivers/base/power/wakeirq.c index 0d77cd6fd8d1..404d94c6c8bc 100644 --- a/drivers/base/power/wakeirq.c +++ b/drivers/base/power/wakeirq.c @@ -110,8 +110,10 @@ void dev_pm_clear_wake_irq(struct device *dev) dev->power.wakeirq = NULL; spin_unlock_irqrestore(&dev->power.lock, flags); - if (wirq->dedicated_irq) + if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED) { free_irq(wirq->irq, wirq); + wirq->status &= ~WAKE_IRQ_DEDICATED_MASK; + } kfree(wirq); } EXPORT_SYMBOL_GPL(dev_pm_clear_wake_irq); @@ -179,7 +181,6 @@ int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq) wirq->dev = dev; wirq->irq = irq; - wirq->dedicated_irq = true; irq_set_status_flags(irq, IRQ_NOAUTOEN); /* @@ -195,6 +196,8 @@ int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq) if (err) goto err_free_irq; + wirq->status = WAKE_IRQ_DEDICATED_ALLOCATED; + return err; err_free_irq: @@ -210,9 +213,9 @@ EXPORT_SYMBOL_GPL(dev_pm_set_dedicated_wake_irq); * dev_pm_enable_wake_irq - Enable device wake-up interrupt * @dev: Device * - * Called from the bus code or the device driver for - * runtime_suspend() to enable the wake-up interrupt while - * the device is running. + * Optionally called from the bus code or the device driver for + * runtime_resume() to override the PM runtime core managed wake-up + * interrupt handling to enable the wake-up interrupt. * * Note that for runtime_suspend()) the wake-up interrupts * should be unconditionally enabled unlike for suspend() @@ -222,7 +225,7 @@ void dev_pm_enable_wake_irq(struct device *dev) { struct wake_irq *wirq = dev->power.wakeirq; - if (wirq && wirq->dedicated_irq) + if (wirq && (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED)) enable_irq(wirq->irq); } EXPORT_SYMBOL_GPL(dev_pm_enable_wake_irq); @@ -231,19 +234,72 @@ EXPORT_SYMBOL_GPL(dev_pm_enable_wake_irq); * dev_pm_disable_wake_irq - Disable device wake-up interrupt * @dev: Device * - * Called from the bus code or the device driver for - * runtime_resume() to disable the wake-up interrupt while - * the device is running. + * Optionally called from the bus code or the device driver for + * runtime_suspend() to override the PM runtime core managed wake-up + * interrupt handling to disable the wake-up interrupt. */ void dev_pm_disable_wake_irq(struct device *dev) { struct wake_irq *wirq = dev->power.wakeirq; - if (wirq && wirq->dedicated_irq) + if (wirq && (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED)) disable_irq_nosync(wirq->irq); } EXPORT_SYMBOL_GPL(dev_pm_disable_wake_irq); +/** + * dev_pm_enable_wake_irq_check - Checks and enables wake-up interrupt + * @dev: Device + * @can_change_status: Can change wake-up interrupt status + * + * Enables wakeirq conditionally. We need to enable wake-up interrupt + * lazily on the first rpm_suspend(). This is needed as the consumer device + * starts in RPM_SUSPENDED state, and the the first pm_runtime_get() would + * otherwise try to disable already disabled wakeirq. The wake-up interrupt + * starts disabled with IRQ_NOAUTOEN set. + * + * Should be only called from rpm_suspend() and rpm_resume() path. + * Caller must hold &dev->power.lock to change wirq->status + */ +void dev_pm_enable_wake_irq_check(struct device *dev, + bool can_change_status) +{ + struct wake_irq *wirq = dev->power.wakeirq; + + if (!wirq || !((wirq->status & WAKE_IRQ_DEDICATED_MASK))) + return; + + if (likely(wirq->status & WAKE_IRQ_DEDICATED_MANAGED)) { + goto enable; + } else if (can_change_status) { + wirq->status |= WAKE_IRQ_DEDICATED_MANAGED; + goto enable; + } + + return; + +enable: + enable_irq(wirq->irq); +} + +/** + * dev_pm_disable_wake_irq_check - Checks and disables wake-up interrupt + * @dev: Device + * + * Disables wake-up interrupt conditionally based on status. + * Should be only called from rpm_suspend() and rpm_resume() path. + */ +void dev_pm_disable_wake_irq_check(struct device *dev) +{ + struct wake_irq *wirq = dev->power.wakeirq; + + if (!wirq || !((wirq->status & WAKE_IRQ_DEDICATED_MASK))) + return; + + if (wirq->status & WAKE_IRQ_DEDICATED_MANAGED) + disable_irq_nosync(wirq->irq); +} + /** * dev_pm_arm_wake_irq - Arm device wake-up * @wirq: Device wake-up interrupt -- 2.30.2