On Mon, Oct 25, 2021 at 9:02 AM Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx> wrote: > > When the dedicated wake IRQ is level trigger, and it uses the > device's low-power status as the wakeup source, that means if the > device is not in low-power state, the wake IRQ will be triggered > if enabled; For this case, need enable the wake IRQ after running > the device's ->runtime_suspend() which make it enter low-power state. > > e.g. > Assume the wake IRQ is a low level trigger type, and the wakeup > signal comes from the low-power status of the device. > The wakeup signal is low level at running time (0), and becomes > high level when the device enters low-power state (runtime_suspend > (1) is called), a wakeup event at (2) make the device exit low-power > state, then the wakeup signal also becomes low level. > > ------------------ > | ^ ^| > ---------------- | | -------------- > |<---(0)--->|<--(1)--| (3) (2) (4) > > if enable the wake IRQ before running runtime_suspend during (0), > a wake IRQ will arise, it causes resume immediately; > it works if enable wake IRQ ( e.g. at (3) or (4)) after running > ->runtime_suspend(). > > This patch introduces a new status WAKE_IRQ_DEDICATED_REVERSE to > optionally support enabling wake IRQ after running ->runtime_suspend(). > > Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx> I don't really have anything to add regarding the code. The kerneldoc comments could be improved, but I can take care of this when applying the patch. Please collect ACKs for the remaining 2 patches in the series and I will pick up all three. Thanks! > --- > v4: changes according to Rafael's suggestions > 1. rename new flag as WAKE_IRQ_DEDICATED_REVERSE; > 2. add __dev_pm_set_dedicated_wake_irq() with flag parameter, then > rebuild dev_pm_set_dedicated_wake_irq() and add new api > dev_pm_set_dedicated_wake_irq_reverse(); > 3. rename the new added parameter as cond_disable in > dev_pm_disable_wake_irq_check(), and also simplify its flow; > 4. modify some comments > > v3: add new status suggested by Rafael > > v2: add more commit message > > Use the falling edge trigger interrupt suggested by Ikjoon [1], it > works well at firstly when only use this related wakeup source, but > encounter issues if use other wakeup sources to wakeup platform as > below steps: > 1. use another wakeup source to wake up the suspended system; > 2. the consumer's resume() will be called, and exits sleep state; > 3. the consumer's wakeup signal will fall into low level, due to > currently the wakeup irq is disabled, the wake-irq is pending; > 4. the consumer tries to enter runtime suspend, but there is a > pending wakeup irq, so will resume again, this will repeat > endlessly. > > Send out the patch again for further discussion. > > [1]: https://patchwork.kernel.org/patch/12190407 > > --- > drivers/base/power/power.h | 7 ++- > drivers/base/power/runtime.c | 6 ++- > drivers/base/power/wakeirq.c | 101 +++++++++++++++++++++++++++-------- > include/linux/pm_wakeirq.h | 9 +++- > 4 files changed, 96 insertions(+), 27 deletions(-) > > diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h > index 54292cdd7808..0eb7f02b3ad5 100644 > --- a/drivers/base/power/power.h > +++ b/drivers/base/power/power.h > @@ -25,8 +25,10 @@ extern u64 pm_runtime_active_time(struct device *dev); > > #define WAKE_IRQ_DEDICATED_ALLOCATED BIT(0) > #define WAKE_IRQ_DEDICATED_MANAGED BIT(1) > +#define WAKE_IRQ_DEDICATED_REVERSE BIT(2) > #define WAKE_IRQ_DEDICATED_MASK (WAKE_IRQ_DEDICATED_ALLOCATED | \ > - WAKE_IRQ_DEDICATED_MANAGED) > + WAKE_IRQ_DEDICATED_MANAGED | \ > + WAKE_IRQ_DEDICATED_REVERSE) > > struct wake_irq { > struct device *dev; > @@ -39,7 +41,8 @@ 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); > +extern void dev_pm_disable_wake_irq_check(struct device *dev, bool cond_disable); > +extern void dev_pm_enable_wake_irq_complete(struct device *dev); > > #ifdef CONFIG_PM_SLEEP > > diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c > index ec94049442b9..d504cd4ab3cb 100644 > --- a/drivers/base/power/runtime.c > +++ b/drivers/base/power/runtime.c > @@ -645,6 +645,8 @@ static int rpm_suspend(struct device *dev, int rpmflags) > if (retval) > goto fail; > > + dev_pm_enable_wake_irq_complete(dev); > + > no_callback: > __update_runtime_status(dev, RPM_SUSPENDED); > pm_runtime_deactivate_timer(dev); > @@ -690,7 +692,7 @@ static int rpm_suspend(struct device *dev, int rpmflags) > return retval; > > fail: > - dev_pm_disable_wake_irq_check(dev); > + dev_pm_disable_wake_irq_check(dev, true); > __update_runtime_status(dev, RPM_ACTIVE); > dev->power.deferred_resume = false; > wake_up_all(&dev->power.wait_queue); > @@ -873,7 +875,7 @@ static int rpm_resume(struct device *dev, int rpmflags) > > callback = RPM_GET_CALLBACK(dev, runtime_resume); > > - dev_pm_disable_wake_irq_check(dev); > + dev_pm_disable_wake_irq_check(dev, false); > retval = rpm_callback(callback, dev); > if (retval) { > __update_runtime_status(dev, RPM_SUSPENDED); > diff --git a/drivers/base/power/wakeirq.c b/drivers/base/power/wakeirq.c > index b91a3a9bf9f6..76c163a89104 100644 > --- a/drivers/base/power/wakeirq.c > +++ b/drivers/base/power/wakeirq.c > @@ -142,24 +142,7 @@ static irqreturn_t handle_threaded_wake_irq(int irq, void *_wirq) > return IRQ_HANDLED; > } > > -/** > - * dev_pm_set_dedicated_wake_irq - Request a dedicated wake-up interrupt > - * @dev: Device entry > - * @irq: Device wake-up interrupt > - * > - * Unless your hardware has separate wake-up interrupts in addition > - * to the device IO interrupts, you don't need this. > - * > - * Sets up a threaded interrupt handler for a device that has > - * a dedicated wake-up interrupt in addition to the device IO > - * interrupt. > - * > - * The interrupt starts disabled, and needs to be managed for > - * the device by the bus code or the device driver using > - * dev_pm_enable_wake_irq() and dev_pm_disable_wake_irq() > - * functions. > - */ > -int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq) > +static int __dev_pm_set_dedicated_wake_irq(struct device *dev, int irq, unsigned int flag) > { > struct wake_irq *wirq; > int err; > @@ -197,7 +180,7 @@ int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq) > if (err) > goto err_free_irq; > > - wirq->status = WAKE_IRQ_DEDICATED_ALLOCATED; > + wirq->status = WAKE_IRQ_DEDICATED_ALLOCATED | flag; > > return err; > > @@ -210,8 +193,57 @@ int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq) > > return err; > } > + > + > +/** > + * dev_pm_set_dedicated_wake_irq - Request a dedicated wake-up interrupt > + * @dev: Device entry > + * @irq: Device wake-up interrupt > + * > + * Unless your hardware has separate wake-up interrupts in addition > + * to the device IO interrupts, you don't need this. > + * > + * Sets up a threaded interrupt handler for a device that has > + * a dedicated wake-up interrupt in addition to the device IO > + * interrupt. > + * > + * The interrupt starts disabled, and needs to be managed for > + * the device by the bus code or the device driver using > + * dev_pm_enable_wake_irq*() and dev_pm_disable_wake_irq*() > + * functions. > + */ > +int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq) > +{ > + return __dev_pm_set_dedicated_wake_irq(dev, irq, 0); > +} > EXPORT_SYMBOL_GPL(dev_pm_set_dedicated_wake_irq); > > +/** > + * dev_pm_set_dedicated_wake_irq_reverse - Request a dedicated wake-up interrupt > + * with setting flag WAKE_IRQ_DEDICATED_REVERSE > + * @dev: Device entry > + * @irq: Device wake-up interrupt > + * > + * Unless your hardware has separate wake-up interrupts in addition > + * to the device IO interrupts, you don't need this. > + * > + * Sets up a threaded interrupt handler for a device that has a dedicated > + * wake-up interrupt in addition to the device IO interrupt. It sets > + * the status of WAKE_IRQ_DEDICATED_REVERSE to tell rpm_suspend() > + * to enable dedicated wake-up interrupt after running the > + * ->runtime_suspend() > + * > + * The interrupt starts disabled, and needs to be managed for > + * the device by the bus code or the device driver using > + * dev_pm_enable_wake_irq*() and dev_pm_disable_wake_irq*() > + * functions. > + */ > +int dev_pm_set_dedicated_wake_irq_reverse(struct device *dev, int irq) > +{ > + return __dev_pm_set_dedicated_wake_irq(dev, irq, WAKE_IRQ_DEDICATED_REVERSE); > +} > +EXPORT_SYMBOL_GPL(dev_pm_set_dedicated_wake_irq_reverse); > + > /** > * dev_pm_enable_wake_irq - Enable device wake-up interrupt > * @dev: Device > @@ -282,27 +314,54 @@ void dev_pm_enable_wake_irq_check(struct device *dev, > return; > > enable: > - enable_irq(wirq->irq); > + if (!can_change_status || !(wirq->status & WAKE_IRQ_DEDICATED_REVERSE)) > + enable_irq(wirq->irq); > } > > /** > * dev_pm_disable_wake_irq_check - Checks and disables wake-up interrupt > * @dev: Device > + * @cond_disable: if set, also check WAKE_IRQ_DEDICATED_REVERSE > * > * 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) > +void dev_pm_disable_wake_irq_check(struct device *dev, bool cond_disable) > { > struct wake_irq *wirq = dev->power.wakeirq; > > if (!wirq || !(wirq->status & WAKE_IRQ_DEDICATED_MASK)) > return; > > + if (cond_disable && (wirq->status & WAKE_IRQ_DEDICATED_REVERSE)) > + return; > + > if (wirq->status & WAKE_IRQ_DEDICATED_MANAGED) > disable_irq_nosync(wirq->irq); > } > > +/** > + * dev_pm_enable_wake_irq_complete - enable wake IRQ not enabled before > + * @dev: Device using the wake IRQ > + * > + * Enable wake IRQ conditionally based on status, mainly used if want to > + * enable wake IRQ after running ->runtime_suspend() which depends on > + * WAKE_IRQ_DEDICATED_REVERSE. > + * > + * Should be only called from rpm_suspend() path. > + */ > +void dev_pm_enable_wake_irq_complete(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 && > + wirq->status & WAKE_IRQ_DEDICATED_REVERSE) > + enable_irq(wirq->irq); > +} > + > /** > * dev_pm_arm_wake_irq - Arm device wake-up > * @wirq: Device wake-up interrupt > diff --git a/include/linux/pm_wakeirq.h b/include/linux/pm_wakeirq.h > index cd5b62db9084..e63a63aa47a3 100644 > --- a/include/linux/pm_wakeirq.h > +++ b/include/linux/pm_wakeirq.h > @@ -17,8 +17,8 @@ > #ifdef CONFIG_PM > > extern int dev_pm_set_wake_irq(struct device *dev, int irq); > -extern int dev_pm_set_dedicated_wake_irq(struct device *dev, > - int irq); > +extern int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq); > +extern int dev_pm_set_dedicated_wake_irq_reverse(struct device *dev, int irq); > extern void dev_pm_clear_wake_irq(struct device *dev); > extern void dev_pm_enable_wake_irq(struct device *dev); > extern void dev_pm_disable_wake_irq(struct device *dev); > @@ -35,6 +35,11 @@ static inline int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq) > return 0; > } > > +static inline int dev_pm_set_dedicated_wake_irq_reverse(struct device *dev, int irq) > +{ > + return 0; > +} > + > static inline void dev_pm_clear_wake_irq(struct device *dev) > { > } > -- > 2.18.0 >
