From d74e278aaf3b0fe4b02af67055aa71babcc0cebe Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 21 Nov 2011 23:33:28 +0100 Subject: PM / Sleep: Remove unnecessary label and jumps to it form PM core code The "End" label in device_prepare() in drivers/base/power/main.c is not necessary and the jumps to it have no real effect, so remove them all. Signed-off-by: Rafael J. Wysocki Reviewed-by: Srivatsa S. Bhat --- drivers/base/power/main.c | 7 ------- 1 file changed, 7 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index c3d2dfcf438d..1172aeaf7ecf 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -1033,22 +1033,16 @@ static int device_prepare(struct device *dev, pm_message_t state) if (dev->pm_domain->ops.prepare) error = dev->pm_domain->ops.prepare(dev); suspend_report_result(dev->pm_domain->ops.prepare, error); - if (error) - goto End; } else if (dev->type && dev->type->pm) { pm_dev_dbg(dev, state, "preparing type "); if (dev->type->pm->prepare) error = dev->type->pm->prepare(dev); suspend_report_result(dev->type->pm->prepare, error); - if (error) - goto End; } else if (dev->class && dev->class->pm) { pm_dev_dbg(dev, state, "preparing class "); if (dev->class->pm->prepare) error = dev->class->pm->prepare(dev); suspend_report_result(dev->class->pm->prepare, error); - if (error) - goto End; } else if (dev->bus && dev->bus->pm) { pm_dev_dbg(dev, state, "preparing "); if (dev->bus->pm->prepare) @@ -1056,7 +1050,6 @@ static int device_prepare(struct device *dev, pm_message_t state) suspend_report_result(dev->bus->pm->prepare, error); } - End: device_unlock(dev); return error; -- cgit v1.2.3-59-g8ed1b From 64e94aafb6a5c4f419e9b8f93950914b5ac162a9 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 21 Nov 2011 23:33:55 +0100 Subject: PM / Sleep: Simplify device_suspend_noirq() Remove a few if () and return statements in device_suspend_noirq() that aren't really necessary. Signed-off-by: Rafael J. Wysocki Reviewed-by: Srivatsa S. Bhat --- drivers/base/power/main.c | 12 ++---------- 1 file changed, 2 insertions(+), 10 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 1172aeaf7ecf..406f82c344fa 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -763,31 +763,23 @@ static pm_message_t resume_event(pm_message_t sleep_state) */ static int device_suspend_noirq(struct device *dev, pm_message_t state) { - int error; + int error = 0; if (dev->pm_domain) { pm_dev_dbg(dev, state, "LATE power domain "); error = pm_noirq_op(dev, &dev->pm_domain->ops, state); - if (error) - return error; } else if (dev->type && dev->type->pm) { pm_dev_dbg(dev, state, "LATE type "); error = pm_noirq_op(dev, dev->type->pm, state); - if (error) - return error; } else if (dev->class && dev->class->pm) { pm_dev_dbg(dev, state, "LATE class "); error = pm_noirq_op(dev, dev->class->pm, state); - if (error) - return error; } else if (dev->bus && dev->bus->pm) { pm_dev_dbg(dev, state, "LATE "); error = pm_noirq_op(dev, dev->bus->pm, state); - if (error) - return error; } - return 0; + return error; } /** -- cgit v1.2.3-59-g8ed1b From 00dc9ad18d707f36b2fb4af98fd2cf0548d2b258 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 1 Dec 2011 00:01:31 +0100 Subject: PM / Runtime: Use device PM QoS constraints (v2) Make the runtime PM core use device PM QoS constraints to check if it is allowed to suspend a given device, so that an error code is returned if the device's own PM QoS constraint is negative or one of its children has already been suspended for too long. If this is not the case, the maximum estimated time the device is allowed to be suspended, computed as the minimum of the device's PM QoS constraint and the PM QoS constraints of its children (reduced by the difference between the current time and their suspend times) is stored in a new device's PM field power.max_time_suspended_ns that can be used by the device's subsystem or PM domain to decide whether or not to put the device into lower-power (and presumably higher-latency) states later (if the constraint is 0, which means "no constraint", the power.max_time_suspended_ns is set to -1). Additionally, the time of execution of the subsystem-level .runtime_suspend() callback for the device is recorded in the new power.suspend_time field for later use by the device's subsystem or PM domain along with power.max_time_suspended_ns (it also is used by the core code when the device's parent is suspended). Introduce a new helper function, pm_runtime_update_max_time_suspended(), allowing subsystems and PM domains (or device drivers) to update the power.max_time_suspended_ns field, for example after changing the power state of a suspended device. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/qos.c | 24 ++++--- drivers/base/power/runtime.c | 148 +++++++++++++++++++++++++++++++++++++------ include/linux/pm.h | 2 + include/linux/pm_qos.h | 3 + include/linux/pm_runtime.h | 5 ++ 5 files changed, 154 insertions(+), 28 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c index 86de6c50fc41..03f4bd069ca8 100644 --- a/drivers/base/power/qos.c +++ b/drivers/base/power/qos.c @@ -47,21 +47,29 @@ static DEFINE_MUTEX(dev_pm_qos_mtx); static BLOCKING_NOTIFIER_HEAD(dev_pm_notifiers); /** - * dev_pm_qos_read_value - Get PM QoS constraint for a given device. + * __dev_pm_qos_read_value - Get PM QoS constraint for a given device. + * @dev: Device to get the PM QoS constraint value for. + * + * This routine must be called with dev->power.lock held. + */ +s32 __dev_pm_qos_read_value(struct device *dev) +{ + struct pm_qos_constraints *c = dev->power.constraints; + + return c ? pm_qos_read_value(c) : 0; +} + +/** + * dev_pm_qos_read_value - Get PM QoS constraint for a given device (locked). * @dev: Device to get the PM QoS constraint value for. */ s32 dev_pm_qos_read_value(struct device *dev) { - struct pm_qos_constraints *c; unsigned long flags; - s32 ret = 0; + s32 ret; spin_lock_irqsave(&dev->power.lock, flags); - - c = dev->power.constraints; - if (c) - ret = pm_qos_read_value(c); - + ret = __dev_pm_qos_read_value(dev); spin_unlock_irqrestore(&dev->power.lock, flags); return ret; diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 8c78443bca8f..068f7ed1f009 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -279,6 +279,47 @@ static int rpm_callback(int (*cb)(struct device *), struct device *dev) return retval != -EACCES ? retval : -EIO; } +struct rpm_qos_data { + ktime_t time_now; + s64 constraint_ns; +}; + +/** + * rpm_update_qos_constraint - Update a given PM QoS constraint data. + * @dev: Device whose timing data to use. + * @data: PM QoS constraint data to update. + * + * Use the suspend timing data of @dev to update PM QoS constraint data pointed + * to by @data. + */ +static int rpm_update_qos_constraint(struct device *dev, void *data) +{ + struct rpm_qos_data *qos = data; + unsigned long flags; + s64 delta_ns; + int ret = 0; + + spin_lock_irqsave(&dev->power.lock, flags); + + if (dev->power.max_time_suspended_ns < 0) + goto out; + + delta_ns = dev->power.max_time_suspended_ns - + ktime_to_ns(ktime_sub(qos->time_now, dev->power.suspend_time)); + if (delta_ns <= 0) { + ret = -EBUSY; + goto out; + } + + if (qos->constraint_ns > delta_ns || qos->constraint_ns == 0) + qos->constraint_ns = delta_ns; + + out: + spin_unlock_irqrestore(&dev->power.lock, flags); + + return ret; +} + /** * rpm_suspend - Carry out runtime suspend of given device. * @dev: Device to suspend. @@ -305,6 +346,7 @@ static int rpm_suspend(struct device *dev, int rpmflags) { int (*callback)(struct device *); struct device *parent = NULL; + struct rpm_qos_data qos; int retval; trace_rpm_suspend(dev, rpmflags); @@ -400,8 +442,38 @@ static int rpm_suspend(struct device *dev, int rpmflags) goto out; } + qos.constraint_ns = __dev_pm_qos_read_value(dev); + if (qos.constraint_ns < 0) { + /* Negative constraint means "never suspend". */ + retval = -EPERM; + goto out; + } + qos.constraint_ns *= NSEC_PER_USEC; + qos.time_now = ktime_get(); + __update_runtime_status(dev, RPM_SUSPENDING); + if (!dev->power.ignore_children) { + if (dev->power.irq_safe) + spin_unlock(&dev->power.lock); + else + spin_unlock_irq(&dev->power.lock); + + retval = device_for_each_child(dev, &qos, + rpm_update_qos_constraint); + + if (dev->power.irq_safe) + spin_lock(&dev->power.lock); + else + spin_lock_irq(&dev->power.lock); + + if (retval) + goto fail; + } + + dev->power.suspend_time = qos.time_now; + dev->power.max_time_suspended_ns = qos.constraint_ns ? : -1; + if (dev->pm_domain) callback = dev->pm_domain->ops.runtime_suspend; else if (dev->type && dev->type->pm) @@ -414,27 +486,9 @@ static int rpm_suspend(struct device *dev, int rpmflags) callback = NULL; retval = rpm_callback(callback, dev); - if (retval) { - __update_runtime_status(dev, RPM_ACTIVE); - dev->power.deferred_resume = false; - if (retval == -EAGAIN || retval == -EBUSY) { - dev->power.runtime_error = 0; + if (retval) + goto fail; - /* - * If the callback routine failed an autosuspend, and - * if the last_busy time has been updated so that there - * is a new autosuspend expiration time, automatically - * reschedule another autosuspend. - */ - if ((rpmflags & RPM_AUTO) && - pm_runtime_autosuspend_expiration(dev) != 0) - goto repeat; - } else { - pm_runtime_cancel_pending(dev); - } - wake_up_all(&dev->power.wait_queue); - goto out; - } no_callback: __update_runtime_status(dev, RPM_SUSPENDED); pm_runtime_deactivate_timer(dev); @@ -466,6 +520,29 @@ static int rpm_suspend(struct device *dev, int rpmflags) trace_rpm_return_int(dev, _THIS_IP_, retval); return retval; + + fail: + __update_runtime_status(dev, RPM_ACTIVE); + dev->power.suspend_time = ktime_set(0, 0); + dev->power.max_time_suspended_ns = -1; + dev->power.deferred_resume = false; + if (retval == -EAGAIN || retval == -EBUSY) { + dev->power.runtime_error = 0; + + /* + * If the callback routine failed an autosuspend, and + * if the last_busy time has been updated so that there + * is a new autosuspend expiration time, automatically + * reschedule another autosuspend. + */ + if ((rpmflags & RPM_AUTO) && + pm_runtime_autosuspend_expiration(dev) != 0) + goto repeat; + } else { + pm_runtime_cancel_pending(dev); + } + wake_up_all(&dev->power.wait_queue); + goto out; } /** @@ -620,6 +697,9 @@ static int rpm_resume(struct device *dev, int rpmflags) if (dev->power.no_callbacks) goto no_callback; /* Assume success. */ + dev->power.suspend_time = ktime_set(0, 0); + dev->power.max_time_suspended_ns = -1; + __update_runtime_status(dev, RPM_RESUMING); if (dev->pm_domain) @@ -1279,6 +1359,9 @@ void pm_runtime_init(struct device *dev) setup_timer(&dev->power.suspend_timer, pm_suspend_timer_fn, (unsigned long)dev); + dev->power.suspend_time = ktime_set(0, 0); + dev->power.max_time_suspended_ns = -1; + init_waitqueue_head(&dev->power.wait_queue); } @@ -1296,3 +1379,28 @@ void pm_runtime_remove(struct device *dev) if (dev->power.irq_safe && dev->parent) pm_runtime_put_sync(dev->parent); } + +/** + * pm_runtime_update_max_time_suspended - Update device's suspend time data. + * @dev: Device to handle. + * @delta_ns: Value to subtract from the device's max_time_suspended_ns field. + * + * Update the device's power.max_time_suspended_ns field by subtracting + * @delta_ns from it. The resulting value of power.max_time_suspended_ns is + * never negative. + */ +void pm_runtime_update_max_time_suspended(struct device *dev, s64 delta_ns) +{ + unsigned long flags; + + spin_lock_irqsave(&dev->power.lock, flags); + + if (delta_ns > 0 && dev->power.max_time_suspended_ns > 0) { + if (dev->power.max_time_suspended_ns > delta_ns) + dev->power.max_time_suspended_ns -= delta_ns; + else + dev->power.max_time_suspended_ns = 0; + } + + spin_unlock_irqrestore(&dev->power.lock, flags); +} diff --git a/include/linux/pm.h b/include/linux/pm.h index 3f3ed83a9aa5..a7676efa6831 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -521,6 +521,8 @@ struct dev_pm_info { unsigned long active_jiffies; unsigned long suspended_jiffies; unsigned long accounting_timestamp; + ktime_t suspend_time; + s64 max_time_suspended_ns; #endif struct pm_subsys_data *subsys_data; /* Owned by the subsystem. */ struct pm_qos_constraints *constraints; diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index 83b0ea302a80..775a3236343d 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -78,6 +78,7 @@ int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier); int pm_qos_request_active(struct pm_qos_request *req); s32 pm_qos_read_value(struct pm_qos_constraints *c); +s32 __dev_pm_qos_read_value(struct device *dev); s32 dev_pm_qos_read_value(struct device *dev); int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req, s32 value); @@ -119,6 +120,8 @@ static inline int pm_qos_request_active(struct pm_qos_request *req) static inline s32 pm_qos_read_value(struct pm_qos_constraints *c) { return 0; } +static inline s32 __dev_pm_qos_read_value(struct device *dev) + { return 0; } static inline s32 dev_pm_qos_read_value(struct device *dev) { return 0; } static inline int dev_pm_qos_add_request(struct device *dev, diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h index d3085e72a0ee..609daae7a014 100644 --- a/include/linux/pm_runtime.h +++ b/include/linux/pm_runtime.h @@ -45,6 +45,8 @@ extern void pm_runtime_irq_safe(struct device *dev); extern void __pm_runtime_use_autosuspend(struct device *dev, bool use); extern void pm_runtime_set_autosuspend_delay(struct device *dev, int delay); extern unsigned long pm_runtime_autosuspend_expiration(struct device *dev); +extern void pm_runtime_update_max_time_suspended(struct device *dev, + s64 delta_ns); static inline bool pm_children_suspended(struct device *dev) { @@ -148,6 +150,9 @@ static inline void pm_runtime_set_autosuspend_delay(struct device *dev, static inline unsigned long pm_runtime_autosuspend_expiration( struct device *dev) { return 0; } +static inline void pm_runtime_update_max_time_suspended(struct device *dev, + s64 delta_ns) {} + #endif /* !CONFIG_PM_RUNTIME */ static inline int pm_runtime_idle(struct device *dev) -- cgit v1.2.3-59-g8ed1b From d5e4cbfe2049fca375cb19c4bc0cf676e8b4a88a Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 27 Nov 2011 13:11:36 +0100 Subject: PM / Domains: Make it possible to use per-device domain callbacks The current generic PM domains code requires that the same .stop(), .start() and .active_wakeup() device callback routines be used for all devices in the given domain, which is inflexible and may not cover some specific use cases. For this reason, make it possible to use device specific .start()/.stop() and .active_wakeup() callback routines by adding corresponding callback pointers to struct generic_pm_domain_data. Add a new helper routine, pm_genpd_register_callbacks(), that can be used to populate the new per-device callback pointers. Modify the shmobile's power domains code to allow drivers to add their own code to be run during the device stop and start operations with the help of the new callback pointers. Signed-off-by: Rafael J. Wysocki Acked-by: Magnus Damm --- arch/arm/mach-shmobile/pm-sh7372.c | 40 +++++++++- drivers/base/power/domain.c | 152 ++++++++++++++++++++++++++++--------- include/linux/pm_domain.h | 27 ++++++- 3 files changed, 175 insertions(+), 44 deletions(-) (limited to 'drivers/base') diff --git a/arch/arm/mach-shmobile/pm-sh7372.c b/arch/arm/mach-shmobile/pm-sh7372.c index 34bbcbfb1706..6777bb1be059 100644 --- a/arch/arm/mach-shmobile/pm-sh7372.c +++ b/arch/arm/mach-shmobile/pm-sh7372.c @@ -156,7 +156,10 @@ static void sh7372_a4r_suspend(void) static bool pd_active_wakeup(struct device *dev) { - return true; + bool (*active_wakeup)(struct device *dev); + + active_wakeup = dev_gpd_data(dev)->ops.active_wakeup; + return active_wakeup ? active_wakeup(dev) : true; } static bool sh7372_power_down_forbidden(struct dev_pm_domain *domain) @@ -168,15 +171,44 @@ struct dev_power_governor sh7372_always_on_gov = { .power_down_ok = sh7372_power_down_forbidden, }; +static int sh7372_stop_dev(struct device *dev) +{ + int (*stop)(struct device *dev); + + stop = dev_gpd_data(dev)->ops.stop; + if (stop) { + int ret = stop(dev); + if (ret) + return ret; + } + return pm_clk_suspend(dev); +} + +static int sh7372_start_dev(struct device *dev) +{ + int (*start)(struct device *dev); + int ret; + + ret = pm_clk_resume(dev); + if (ret) + return ret; + + start = dev_gpd_data(dev)->ops.start; + if (start) + ret = start(dev); + + return ret; +} + void sh7372_init_pm_domain(struct sh7372_pm_domain *sh7372_pd) { struct generic_pm_domain *genpd = &sh7372_pd->genpd; pm_genpd_init(genpd, sh7372_pd->gov, false); - genpd->stop_device = pm_clk_suspend; - genpd->start_device = pm_clk_resume; + genpd->dev_ops.stop = sh7372_stop_dev; + genpd->dev_ops.start = sh7372_start_dev; + genpd->dev_ops.active_wakeup = pd_active_wakeup; genpd->dev_irq_safe = true; - genpd->active_wakeup = pd_active_wakeup; genpd->power_off = pd_power_down; genpd->power_on = pd_power_up; __pd_power_up(sh7372_pd, false); diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 6790cf7eba5a..94afaa2686a6 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -15,6 +15,23 @@ #include #include #include +#include + +#define GENPD_DEV_CALLBACK(genpd, type, callback, dev) \ +({ \ + type (*__routine)(struct device *__d); \ + type __ret = (type)0; \ + \ + __routine = genpd->dev_ops.callback; \ + if (__routine) { \ + __ret = __routine(dev); \ + } else { \ + __routine = dev_gpd_data(dev)->ops.callback; \ + if (__routine) \ + __ret = __routine(dev); \ + } \ + __ret; \ +}) static LIST_HEAD(gpd_list); static DEFINE_MUTEX(gpd_list_lock); @@ -29,6 +46,16 @@ static struct generic_pm_domain *dev_to_genpd(struct device *dev) return pd_to_genpd(dev->pm_domain); } +static int genpd_stop_dev(struct generic_pm_domain *genpd, struct device *dev) +{ + return GENPD_DEV_CALLBACK(genpd, int, stop, dev); +} + +static int genpd_start_dev(struct generic_pm_domain *genpd, struct device *dev) +{ + return GENPD_DEV_CALLBACK(genpd, int, start, dev); +} + static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd) { bool ret = false; @@ -199,13 +226,9 @@ static int __pm_genpd_save_device(struct pm_domain_data *pdd, mutex_unlock(&genpd->lock); if (drv && drv->pm && drv->pm->runtime_suspend) { - if (genpd->start_device) - genpd->start_device(dev); - + genpd_start_dev(genpd, dev); ret = drv->pm->runtime_suspend(dev); - - if (genpd->stop_device) - genpd->stop_device(dev); + genpd_stop_dev(genpd, dev); } mutex_lock(&genpd->lock); @@ -235,13 +258,9 @@ static void __pm_genpd_restore_device(struct pm_domain_data *pdd, mutex_unlock(&genpd->lock); if (drv && drv->pm && drv->pm->runtime_resume) { - if (genpd->start_device) - genpd->start_device(dev); - + genpd_start_dev(genpd, dev); drv->pm->runtime_resume(dev); - - if (genpd->stop_device) - genpd->stop_device(dev); + genpd_stop_dev(genpd, dev); } mutex_lock(&genpd->lock); @@ -413,6 +432,7 @@ static void genpd_power_off_work_fn(struct work_struct *work) static int pm_genpd_runtime_suspend(struct device *dev) { struct generic_pm_domain *genpd; + int ret; dev_dbg(dev, "%s()\n", __func__); @@ -422,11 +442,9 @@ static int pm_genpd_runtime_suspend(struct device *dev) might_sleep_if(!genpd->dev_irq_safe); - if (genpd->stop_device) { - int ret = genpd->stop_device(dev); - if (ret) - return ret; - } + ret = genpd_stop_dev(genpd, dev); + if (ret) + return ret; /* * If power.irq_safe is set, this routine will be run with interrupts @@ -502,8 +520,7 @@ static int pm_genpd_runtime_resume(struct device *dev) mutex_unlock(&genpd->lock); out: - if (genpd->start_device) - genpd->start_device(dev); + genpd_start_dev(genpd, dev); return 0; } @@ -534,6 +551,12 @@ static inline void genpd_power_off_work_fn(struct work_struct *work) {} #ifdef CONFIG_PM_SLEEP +static bool genpd_dev_active_wakeup(struct generic_pm_domain *genpd, + struct device *dev) +{ + return GENPD_DEV_CALLBACK(genpd, bool, active_wakeup, dev); +} + /** * pm_genpd_sync_poweroff - Synchronously power off a PM domain and its masters. * @genpd: PM domain to power off, if possible. @@ -590,7 +613,7 @@ static bool resume_needed(struct device *dev, struct generic_pm_domain *genpd) if (!device_can_wakeup(dev)) return false; - active_wakeup = genpd->active_wakeup && genpd->active_wakeup(dev); + active_wakeup = genpd_dev_active_wakeup(genpd, dev); return device_may_wakeup(dev) ? active_wakeup : !active_wakeup; } @@ -646,7 +669,7 @@ static int pm_genpd_prepare(struct device *dev) /* * The PM domain must be in the GPD_STATE_ACTIVE state at this point, * so pm_genpd_poweron() will return immediately, but if the device - * is suspended (e.g. it's been stopped by .stop_device()), we need + * is suspended (e.g. it's been stopped by genpd_stop_dev()), we need * to make it operational. */ pm_runtime_resume(dev); @@ -714,12 +737,10 @@ static int pm_genpd_suspend_noirq(struct device *dev) if (ret) return ret; - if (dev->power.wakeup_path - && genpd->active_wakeup && genpd->active_wakeup(dev)) + if (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)) return 0; - if (genpd->stop_device) - genpd->stop_device(dev); + genpd_stop_dev(genpd, dev); /* * Since all of the "noirq" callbacks are executed sequentially, it is @@ -761,8 +782,7 @@ static int pm_genpd_resume_noirq(struct device *dev) */ pm_genpd_poweron(genpd); genpd->suspended_count--; - if (genpd->start_device) - genpd->start_device(dev); + genpd_start_dev(genpd, dev); return pm_generic_resume_noirq(dev); } @@ -836,8 +856,7 @@ static int pm_genpd_freeze_noirq(struct device *dev) if (ret) return ret; - if (genpd->stop_device) - genpd->stop_device(dev); + genpd_stop_dev(genpd, dev); return 0; } @@ -864,8 +883,7 @@ static int pm_genpd_thaw_noirq(struct device *dev) if (genpd->suspend_power_off) return 0; - if (genpd->start_device) - genpd->start_device(dev); + genpd_start_dev(genpd, dev); return pm_generic_thaw_noirq(dev); } @@ -938,12 +956,10 @@ static int pm_genpd_dev_poweroff_noirq(struct device *dev) if (ret) return ret; - if (dev->power.wakeup_path - && genpd->active_wakeup && genpd->active_wakeup(dev)) + if (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)) return 0; - if (genpd->stop_device) - genpd->stop_device(dev); + genpd_stop_dev(genpd, dev); /* * Since all of the "noirq" callbacks are executed sequentially, it is @@ -993,8 +1009,7 @@ static int pm_genpd_restore_noirq(struct device *dev) pm_genpd_poweron(genpd); genpd->suspended_count--; - if (genpd->start_device) - genpd->start_device(dev); + genpd_start_dev(genpd, dev); return pm_generic_restore_noirq(dev); } @@ -1279,6 +1294,69 @@ int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd, return ret; } +/** + * pm_genpd_add_callbacks - Add PM domain callbacks to a given device. + * @dev: Device to add the callbacks to. + * @ops: Set of callbacks to add. + */ +int pm_genpd_add_callbacks(struct device *dev, struct gpd_dev_ops *ops) +{ + struct pm_domain_data *pdd; + int ret = 0; + + if (!(dev && dev->power.subsys_data && ops)) + return -EINVAL; + + pm_runtime_disable(dev); + device_pm_lock(); + + pdd = dev->power.subsys_data->domain_data; + if (pdd) { + struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd); + + gpd_data->ops = *ops; + } else { + ret = -EINVAL; + } + + device_pm_unlock(); + pm_runtime_enable(dev); + + return ret; +} +EXPORT_SYMBOL_GPL(pm_genpd_add_callbacks); + +/** + * pm_genpd_remove_callbacks - Remove PM domain callbacks from a given device. + * @dev: Device to remove the callbacks from. + */ +int pm_genpd_remove_callbacks(struct device *dev) +{ + struct pm_domain_data *pdd; + int ret = 0; + + if (!(dev && dev->power.subsys_data)) + return -EINVAL; + + pm_runtime_disable(dev); + device_pm_lock(); + + pdd = dev->power.subsys_data->domain_data; + if (pdd) { + struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd); + + gpd_data->ops = (struct gpd_dev_ops){ 0 }; + } else { + ret = -EINVAL; + } + + device_pm_unlock(); + pm_runtime_enable(dev); + + return ret; +} +EXPORT_SYMBOL_GPL(pm_genpd_remove_callbacks); + /** * pm_genpd_init - Initialize a generic I/O PM domain object. * @genpd: PM domain object to initialize. diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index 65633e5a2bc0..8949d2d202ae 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -23,6 +23,12 @@ struct dev_power_governor { bool (*power_down_ok)(struct dev_pm_domain *domain); }; +struct gpd_dev_ops { + int (*start)(struct device *dev); + int (*stop)(struct device *dev); + bool (*active_wakeup)(struct device *dev); +}; + struct generic_pm_domain { struct dev_pm_domain domain; /* PM domain operations */ struct list_head gpd_list_node; /* Node in the global PM domains list */ @@ -45,9 +51,7 @@ struct generic_pm_domain { bool dev_irq_safe; /* Device callbacks are IRQ-safe */ int (*power_off)(struct generic_pm_domain *domain); int (*power_on)(struct generic_pm_domain *domain); - int (*start_device)(struct device *dev); - int (*stop_device)(struct device *dev); - bool (*active_wakeup)(struct device *dev); + struct gpd_dev_ops dev_ops; }; static inline struct generic_pm_domain *pd_to_genpd(struct dev_pm_domain *pd) @@ -64,6 +68,7 @@ struct gpd_link { struct generic_pm_domain_data { struct pm_domain_data base; + struct gpd_dev_ops ops; bool need_restore; }; @@ -73,6 +78,11 @@ static inline struct generic_pm_domain_data *to_gpd_data(struct pm_domain_data * } #ifdef CONFIG_PM_GENERIC_DOMAINS +static inline struct generic_pm_domain_data *dev_gpd_data(struct device *dev) +{ + return to_gpd_data(dev->power.subsys_data->domain_data); +} + extern int pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev); extern int pm_genpd_remove_device(struct generic_pm_domain *genpd, @@ -81,6 +91,8 @@ extern int pm_genpd_add_subdomain(struct generic_pm_domain *genpd, struct generic_pm_domain *new_subdomain); extern int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd, struct generic_pm_domain *target); +extern int pm_genpd_add_callbacks(struct device *dev, struct gpd_dev_ops *ops); +extern int pm_genpd_remove_callbacks(struct device *dev); extern void pm_genpd_init(struct generic_pm_domain *genpd, struct dev_power_governor *gov, bool is_off); extern int pm_genpd_poweron(struct generic_pm_domain *genpd); @@ -105,6 +117,15 @@ static inline int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd, { return -ENOSYS; } +static inline int pm_genpd_add_callbacks(struct device *dev, + struct gpd_dev_ops *ops) +{ + return -ENOSYS; +} +static inline int pm_genpd_remove_callbacks(struct device *dev) +{ + return -ENOSYS; +} static inline void pm_genpd_init(struct generic_pm_domain *genpd, struct dev_power_governor *gov, bool is_off) {} static inline int pm_genpd_poweron(struct generic_pm_domain *genpd) -- cgit v1.2.3-59-g8ed1b From ecf00475f229fcf06362412ad2d15a3267e354a1 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 27 Nov 2011 13:11:44 +0100 Subject: PM / Domains: Introduce "save/restore state" device callbacks The current PM domains code uses device drivers' .runtime_suspend() and .runtime_resume() callbacks as the "save device state" and "restore device state" operations, which may not be appropriate in general, because it forces drivers to assume that they always will be used with generic PM domains. However, in theory, the same hardware may be used in devices that don't belong to any PM domain, in which case it would be necessary to add "fake" PM domains to satisfy the above assumption. It also may be located in a PM domain that's not handled with the help of the generic code. To allow device drivers that may be used along with the generic PM domains code of more flexibility, introduce new device callbacks, .save_state() and .restore_state(), that can be supplied by the drivers in addition to their "standard" runtime PM callbacks. This will allow the drivers to be designed to work with generic PM domains as well as without them. For backwards compatibility, introduce default .save_state() and .restore_state() callback routines for PM domains that will execute a device driver's .runtime_suspend() and .runtime_resume() callbacks, respectively, for the given device if the driver doesn't provide its own implementations of .save_state() and .restore_state(). Signed-off-by: Rafael J. Wysocki --- drivers/base/power/domain.c | 68 +++++++++++++++++++++++++++++++++++++-------- include/linux/pm_domain.h | 2 ++ 2 files changed, 58 insertions(+), 12 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 94afaa2686a6..3c9451b10427 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -56,6 +56,16 @@ static int genpd_start_dev(struct generic_pm_domain *genpd, struct device *dev) return GENPD_DEV_CALLBACK(genpd, int, start, dev); } +static int genpd_save_dev(struct generic_pm_domain *genpd, struct device *dev) +{ + return GENPD_DEV_CALLBACK(genpd, int, save_state, dev); +} + +static int genpd_restore_dev(struct generic_pm_domain *genpd, struct device *dev) +{ + return GENPD_DEV_CALLBACK(genpd, int, restore_state, dev); +} + static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd) { bool ret = false; @@ -217,7 +227,6 @@ static int __pm_genpd_save_device(struct pm_domain_data *pdd, { struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd); struct device *dev = pdd->dev; - struct device_driver *drv = dev->driver; int ret = 0; if (gpd_data->need_restore) @@ -225,11 +234,9 @@ static int __pm_genpd_save_device(struct pm_domain_data *pdd, mutex_unlock(&genpd->lock); - if (drv && drv->pm && drv->pm->runtime_suspend) { - genpd_start_dev(genpd, dev); - ret = drv->pm->runtime_suspend(dev); - genpd_stop_dev(genpd, dev); - } + genpd_start_dev(genpd, dev); + ret = genpd_save_dev(genpd, dev); + genpd_stop_dev(genpd, dev); mutex_lock(&genpd->lock); @@ -250,18 +257,15 @@ static void __pm_genpd_restore_device(struct pm_domain_data *pdd, { struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd); struct device *dev = pdd->dev; - struct device_driver *drv = dev->driver; if (!gpd_data->need_restore) return; mutex_unlock(&genpd->lock); - if (drv && drv->pm && drv->pm->runtime_resume) { - genpd_start_dev(genpd, dev); - drv->pm->runtime_resume(dev); - genpd_stop_dev(genpd, dev); - } + genpd_start_dev(genpd, dev); + genpd_restore_dev(genpd, dev); + genpd_stop_dev(genpd, dev); mutex_lock(&genpd->lock); @@ -1357,6 +1361,44 @@ int pm_genpd_remove_callbacks(struct device *dev) } EXPORT_SYMBOL_GPL(pm_genpd_remove_callbacks); +/** + * pm_genpd_default_save_state - Default "save device state" for PM domians. + * @dev: Device to handle. + */ +static int pm_genpd_default_save_state(struct device *dev) +{ + int (*cb)(struct device *__dev); + struct device_driver *drv = dev->driver; + + cb = dev_gpd_data(dev)->ops.save_state; + if (cb) + return cb(dev); + + if (drv && drv->pm && drv->pm->runtime_suspend) + return drv->pm->runtime_suspend(dev); + + return 0; +} + +/** + * pm_genpd_default_restore_state - Default PM domians "restore device state". + * @dev: Device to handle. + */ +static int pm_genpd_default_restore_state(struct device *dev) +{ + int (*cb)(struct device *__dev); + struct device_driver *drv = dev->driver; + + cb = dev_gpd_data(dev)->ops.restore_state; + if (cb) + return cb(dev); + + if (drv && drv->pm && drv->pm->runtime_resume) + return drv->pm->runtime_resume(dev); + + return 0; +} + /** * pm_genpd_init - Initialize a generic I/O PM domain object. * @genpd: PM domain object to initialize. @@ -1400,6 +1442,8 @@ void pm_genpd_init(struct generic_pm_domain *genpd, genpd->domain.ops.restore_noirq = pm_genpd_restore_noirq; genpd->domain.ops.restore = pm_genpd_restore; genpd->domain.ops.complete = pm_genpd_complete; + genpd->dev_ops.save_state = pm_genpd_default_save_state; + genpd->dev_ops.restore_state = pm_genpd_default_restore_state; mutex_lock(&gpd_list_lock); list_add(&genpd->gpd_list_node, &gpd_list); mutex_unlock(&gpd_list_lock); diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index 8949d2d202ae..731080dad250 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -26,6 +26,8 @@ struct dev_power_governor { struct gpd_dev_ops { int (*start)(struct device *dev); int (*stop)(struct device *dev); + int (*save_state)(struct device *dev); + int (*restore_state)(struct device *dev); bool (*active_wakeup)(struct device *dev); }; -- cgit v1.2.3-59-g8ed1b From d23b9b00cdde5c93b914a172cecd57d5625fcd04 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 27 Nov 2011 13:11:51 +0100 Subject: PM / Domains: Rework system suspend callback routines (v2) The current generic PM domains code attempts to use the generic system suspend operations along with the domains' device stop/start routines, which requires device drivers to assume that their system suspend/resume (and hibernation/restore) callbacks will always be used with generic PM domains. However, in theory, the same hardware may be used in devices that don't belong to any PM domain, in which case it would be necessary to add "fake" PM domains to satisfy the above assumption. Also, the domain the hardware belongs to may not be handled with the help of the generic code. To allow device drivers that may be used along with the generic PM domains code of more flexibility, add new device callbacks, .suspend(), .suspend_late(), .resume_early(), .resume(), .freeze(), .freeze_late(), .thaw_early(), and .thaw(), that can be supplied by the drivers in addition to their "standard" system suspend and hibernation callbacks. These new callbacks, if defined, will be used by the generic PM domains code for the handling of system suspend and hibernation instead of the "standard" ones. This will allow drivers to be designed to work with generic PM domains as well as without them. For backwards compatibility, introduce default implementations of the new callbacks for PM domains that will execute pm_generic_suspend(), pm_generic_suspend_noirq(), pm_generic_resume_noirq(), pm_generic_resume(), pm_generic_freeze(), pm_generic_freeze_noirq(), pm_generic_thaw_noirq(), and pm_generic_thaw(), respectively, for the given device if its driver doesn't define those callbacks. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/domain.c | 249 ++++++++++++++++++++++++++------------------ include/linux/pm_domain.h | 8 ++ 2 files changed, 158 insertions(+), 99 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 3c9451b10427..9a77080cb799 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -561,6 +561,46 @@ static bool genpd_dev_active_wakeup(struct generic_pm_domain *genpd, return GENPD_DEV_CALLBACK(genpd, bool, active_wakeup, dev); } +static int genpd_suspend_dev(struct generic_pm_domain *genpd, struct device *dev) +{ + return GENPD_DEV_CALLBACK(genpd, int, suspend, dev); +} + +static int genpd_suspend_late(struct generic_pm_domain *genpd, struct device *dev) +{ + return GENPD_DEV_CALLBACK(genpd, int, suspend_late, dev); +} + +static int genpd_resume_early(struct generic_pm_domain *genpd, struct device *dev) +{ + return GENPD_DEV_CALLBACK(genpd, int, resume_early, dev); +} + +static int genpd_resume_dev(struct generic_pm_domain *genpd, struct device *dev) +{ + return GENPD_DEV_CALLBACK(genpd, int, resume, dev); +} + +static int genpd_freeze_dev(struct generic_pm_domain *genpd, struct device *dev) +{ + return GENPD_DEV_CALLBACK(genpd, int, freeze, dev); +} + +static int genpd_freeze_late(struct generic_pm_domain *genpd, struct device *dev) +{ + return GENPD_DEV_CALLBACK(genpd, int, freeze_late, dev); +} + +static int genpd_thaw_early(struct generic_pm_domain *genpd, struct device *dev) +{ + return GENPD_DEV_CALLBACK(genpd, int, thaw_early, dev); +} + +static int genpd_thaw_dev(struct generic_pm_domain *genpd, struct device *dev) +{ + return GENPD_DEV_CALLBACK(genpd, int, thaw, dev); +} + /** * pm_genpd_sync_poweroff - Synchronously power off a PM domain and its masters. * @genpd: PM domain to power off, if possible. @@ -712,7 +752,7 @@ static int pm_genpd_suspend(struct device *dev) if (IS_ERR(genpd)) return -EINVAL; - return genpd->suspend_power_off ? 0 : pm_generic_suspend(dev); + return genpd->suspend_power_off ? 0 : genpd_suspend_dev(genpd, dev); } /** @@ -737,7 +777,7 @@ static int pm_genpd_suspend_noirq(struct device *dev) if (genpd->suspend_power_off) return 0; - ret = pm_generic_suspend_noirq(dev); + ret = genpd_suspend_late(genpd, dev); if (ret) return ret; @@ -788,7 +828,7 @@ static int pm_genpd_resume_noirq(struct device *dev) genpd->suspended_count--; genpd_start_dev(genpd, dev); - return pm_generic_resume_noirq(dev); + return genpd_resume_early(genpd, dev); } /** @@ -809,7 +849,7 @@ static int pm_genpd_resume(struct device *dev) if (IS_ERR(genpd)) return -EINVAL; - return genpd->suspend_power_off ? 0 : pm_generic_resume(dev); + return genpd->suspend_power_off ? 0 : genpd_resume_dev(genpd, dev); } /** @@ -830,7 +870,7 @@ static int pm_genpd_freeze(struct device *dev) if (IS_ERR(genpd)) return -EINVAL; - return genpd->suspend_power_off ? 0 : pm_generic_freeze(dev); + return genpd->suspend_power_off ? 0 : genpd_freeze_dev(genpd, dev); } /** @@ -856,7 +896,7 @@ static int pm_genpd_freeze_noirq(struct device *dev) if (genpd->suspend_power_off) return 0; - ret = pm_generic_freeze_noirq(dev); + ret = genpd_freeze_late(genpd, dev); if (ret) return ret; @@ -889,7 +929,7 @@ static int pm_genpd_thaw_noirq(struct device *dev) genpd_start_dev(genpd, dev); - return pm_generic_thaw_noirq(dev); + return genpd_thaw_early(genpd, dev); } /** @@ -910,70 +950,7 @@ static int pm_genpd_thaw(struct device *dev) if (IS_ERR(genpd)) return -EINVAL; - return genpd->suspend_power_off ? 0 : pm_generic_thaw(dev); -} - -/** - * pm_genpd_dev_poweroff - Power off a device belonging to an I/O PM domain. - * @dev: Device to suspend. - * - * Power off a device under the assumption that its pm_domain field points to - * the domain member of an object of type struct generic_pm_domain representing - * a PM domain consisting of I/O devices. - */ -static int pm_genpd_dev_poweroff(struct device *dev) -{ - struct generic_pm_domain *genpd; - - dev_dbg(dev, "%s()\n", __func__); - - genpd = dev_to_genpd(dev); - if (IS_ERR(genpd)) - return -EINVAL; - - return genpd->suspend_power_off ? 0 : pm_generic_poweroff(dev); -} - -/** - * pm_genpd_dev_poweroff_noirq - Late power off of a device from a PM domain. - * @dev: Device to suspend. - * - * Carry out a late powering off of a device under the assumption that its - * pm_domain field points to the domain member of an object of type - * struct generic_pm_domain representing a PM domain consisting of I/O devices. - */ -static int pm_genpd_dev_poweroff_noirq(struct device *dev) -{ - struct generic_pm_domain *genpd; - int ret; - - dev_dbg(dev, "%s()\n", __func__); - - genpd = dev_to_genpd(dev); - if (IS_ERR(genpd)) - return -EINVAL; - - if (genpd->suspend_power_off) - return 0; - - ret = pm_generic_poweroff_noirq(dev); - if (ret) - return ret; - - if (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)) - return 0; - - genpd_stop_dev(genpd, dev); - - /* - * Since all of the "noirq" callbacks are executed sequentially, it is - * guaranteed that this function will never run twice in parallel for - * the same PM domain, so it is not necessary to use locking here. - */ - genpd->suspended_count++; - pm_genpd_sync_poweroff(genpd); - - return 0; + return genpd->suspend_power_off ? 0 : genpd_thaw_dev(genpd, dev); } /** @@ -1015,28 +992,7 @@ static int pm_genpd_restore_noirq(struct device *dev) genpd->suspended_count--; genpd_start_dev(genpd, dev); - return pm_generic_restore_noirq(dev); -} - -/** - * pm_genpd_restore - Restore a device belonging to an I/O power domain. - * @dev: Device to resume. - * - * Restore a device under the assumption that its pm_domain field points to the - * domain member of an object of type struct generic_pm_domain representing - * a power domain consisting of I/O devices. - */ -static int pm_genpd_restore(struct device *dev) -{ - struct generic_pm_domain *genpd; - - dev_dbg(dev, "%s()\n", __func__); - - genpd = dev_to_genpd(dev); - if (IS_ERR(genpd)) - return -EINVAL; - - return genpd->suspend_power_off ? 0 : pm_generic_restore(dev); + return genpd_resume_early(genpd, dev); } /** @@ -1086,10 +1042,7 @@ static void pm_genpd_complete(struct device *dev) #define pm_genpd_freeze_noirq NULL #define pm_genpd_thaw_noirq NULL #define pm_genpd_thaw NULL -#define pm_genpd_dev_poweroff_noirq NULL -#define pm_genpd_dev_poweroff NULL #define pm_genpd_restore_noirq NULL -#define pm_genpd_restore NULL #define pm_genpd_complete NULL #endif /* CONFIG_PM_SLEEP */ @@ -1361,6 +1314,8 @@ int pm_genpd_remove_callbacks(struct device *dev) } EXPORT_SYMBOL_GPL(pm_genpd_remove_callbacks); +/* Default device callbacks for generic PM domains. */ + /** * pm_genpd_default_save_state - Default "save device state" for PM domians. * @dev: Device to handle. @@ -1399,6 +1354,94 @@ static int pm_genpd_default_restore_state(struct device *dev) return 0; } +/** + * pm_genpd_default_suspend - Default "device suspend" for PM domians. + * @dev: Device to handle. + */ +static int pm_genpd_default_suspend(struct device *dev) +{ + int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.freeze; + + return cb ? cb(dev) : pm_generic_suspend(dev); +} + +/** + * pm_genpd_default_suspend_late - Default "late device suspend" for PM domians. + * @dev: Device to handle. + */ +static int pm_genpd_default_suspend_late(struct device *dev) +{ + int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.freeze_late; + + return cb ? cb(dev) : pm_generic_suspend_noirq(dev); +} + +/** + * pm_genpd_default_resume_early - Default "early device resume" for PM domians. + * @dev: Device to handle. + */ +static int pm_genpd_default_resume_early(struct device *dev) +{ + int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.thaw_early; + + return cb ? cb(dev) : pm_generic_resume_noirq(dev); +} + +/** + * pm_genpd_default_resume - Default "device resume" for PM domians. + * @dev: Device to handle. + */ +static int pm_genpd_default_resume(struct device *dev) +{ + int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.thaw; + + return cb ? cb(dev) : pm_generic_resume(dev); +} + +/** + * pm_genpd_default_freeze - Default "device freeze" for PM domians. + * @dev: Device to handle. + */ +static int pm_genpd_default_freeze(struct device *dev) +{ + int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.freeze; + + return cb ? cb(dev) : pm_generic_freeze(dev); +} + +/** + * pm_genpd_default_freeze_late - Default "late device freeze" for PM domians. + * @dev: Device to handle. + */ +static int pm_genpd_default_freeze_late(struct device *dev) +{ + int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.freeze_late; + + return cb ? cb(dev) : pm_generic_freeze_noirq(dev); +} + +/** + * pm_genpd_default_thaw_early - Default "early device thaw" for PM domians. + * @dev: Device to handle. + */ +static int pm_genpd_default_thaw_early(struct device *dev) +{ + int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.thaw_early; + + return cb ? cb(dev) : pm_generic_thaw_noirq(dev); +} + +/** + * pm_genpd_default_thaw - Default "device thaw" for PM domians. + * @dev: Device to handle. + */ +static int pm_genpd_default_thaw(struct device *dev) +{ + int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.thaw; + + return cb ? cb(dev) : pm_generic_thaw(dev); +} + /** * pm_genpd_init - Initialize a generic I/O PM domain object. * @genpd: PM domain object to initialize. @@ -1437,13 +1480,21 @@ void pm_genpd_init(struct generic_pm_domain *genpd, genpd->domain.ops.freeze_noirq = pm_genpd_freeze_noirq; genpd->domain.ops.thaw_noirq = pm_genpd_thaw_noirq; genpd->domain.ops.thaw = pm_genpd_thaw; - genpd->domain.ops.poweroff = pm_genpd_dev_poweroff; - genpd->domain.ops.poweroff_noirq = pm_genpd_dev_poweroff_noirq; + genpd->domain.ops.poweroff = pm_genpd_suspend; + genpd->domain.ops.poweroff_noirq = pm_genpd_suspend_noirq; genpd->domain.ops.restore_noirq = pm_genpd_restore_noirq; - genpd->domain.ops.restore = pm_genpd_restore; + genpd->domain.ops.restore = pm_genpd_resume; genpd->domain.ops.complete = pm_genpd_complete; genpd->dev_ops.save_state = pm_genpd_default_save_state; genpd->dev_ops.restore_state = pm_genpd_default_restore_state; + genpd->dev_ops.freeze = pm_genpd_default_suspend; + genpd->dev_ops.freeze_late = pm_genpd_default_suspend_late; + genpd->dev_ops.thaw_early = pm_genpd_default_resume_early; + genpd->dev_ops.thaw = pm_genpd_default_resume; + genpd->dev_ops.freeze = pm_genpd_default_freeze; + genpd->dev_ops.freeze_late = pm_genpd_default_freeze_late; + genpd->dev_ops.thaw_early = pm_genpd_default_thaw_early; + genpd->dev_ops.thaw = pm_genpd_default_thaw; mutex_lock(&gpd_list_lock); list_add(&genpd->gpd_list_node, &gpd_list); mutex_unlock(&gpd_list_lock); diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index 731080dad250..10a197dce07e 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -28,6 +28,14 @@ struct gpd_dev_ops { int (*stop)(struct device *dev); int (*save_state)(struct device *dev); int (*restore_state)(struct device *dev); + int (*suspend)(struct device *dev); + int (*suspend_late)(struct device *dev); + int (*resume_early)(struct device *dev); + int (*resume)(struct device *dev); + int (*freeze)(struct device *dev); + int (*freeze_late)(struct device *dev); + int (*thaw_early)(struct device *dev); + int (*thaw)(struct device *dev); bool (*active_wakeup)(struct device *dev); }; -- cgit v1.2.3-59-g8ed1b From b02c999ac325e977585abeb4caf6e0a2ee21e30b Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 1 Dec 2011 00:02:05 +0100 Subject: PM / Domains: Add device stop governor function (v4) Add a function deciding whether or not devices should be stopped in pm_genpd_runtime_suspend() depending on their PM QoS constraints and stop/start timing values. Make it possible to add information used by this function to device objects. Signed-off-by: Rafael J. Wysocki Acked-by: Magnus Damm --- arch/arm/mach-shmobile/pm-sh7372.c | 4 ++- drivers/base/power/Makefile | 2 +- drivers/base/power/domain.c | 33 +++++++++++++++---- drivers/base/power/domain_governor.c | 33 +++++++++++++++++++ include/linux/pm_domain.h | 63 +++++++++++++++++++++++++++++++----- 5 files changed, 118 insertions(+), 17 deletions(-) create mode 100644 drivers/base/power/domain_governor.c (limited to 'drivers/base') diff --git a/arch/arm/mach-shmobile/pm-sh7372.c b/arch/arm/mach-shmobile/pm-sh7372.c index 6777bb1be059..adf1765e69c6 100644 --- a/arch/arm/mach-shmobile/pm-sh7372.c +++ b/arch/arm/mach-shmobile/pm-sh7372.c @@ -169,6 +169,7 @@ static bool sh7372_power_down_forbidden(struct dev_pm_domain *domain) struct dev_power_governor sh7372_always_on_gov = { .power_down_ok = sh7372_power_down_forbidden, + .stop_ok = default_stop_ok, }; static int sh7372_stop_dev(struct device *dev) @@ -203,8 +204,9 @@ static int sh7372_start_dev(struct device *dev) void sh7372_init_pm_domain(struct sh7372_pm_domain *sh7372_pd) { struct generic_pm_domain *genpd = &sh7372_pd->genpd; + struct dev_power_governor *gov = sh7372_pd->gov; - pm_genpd_init(genpd, sh7372_pd->gov, false); + pm_genpd_init(genpd, gov ? : &simple_qos_governor, false); genpd->dev_ops.stop = sh7372_stop_dev; genpd->dev_ops.start = sh7372_start_dev; genpd->dev_ops.active_wakeup = pd_active_wakeup; diff --git a/drivers/base/power/Makefile b/drivers/base/power/Makefile index 81676dd17900..2e58ebb1f6c0 100644 --- a/drivers/base/power/Makefile +++ b/drivers/base/power/Makefile @@ -3,7 +3,7 @@ obj-$(CONFIG_PM_SLEEP) += main.o wakeup.o obj-$(CONFIG_PM_RUNTIME) += runtime.o obj-$(CONFIG_PM_TRACE_RTC) += trace.o obj-$(CONFIG_PM_OPP) += opp.o -obj-$(CONFIG_PM_GENERIC_DOMAINS) += domain.o +obj-$(CONFIG_PM_GENERIC_DOMAINS) += domain.o domain_governor.o obj-$(CONFIG_HAVE_CLK) += clock_ops.o ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 9a77080cb799..3af9f5a71ad5 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -38,7 +38,7 @@ static DEFINE_MUTEX(gpd_list_lock); #ifdef CONFIG_PM -static struct generic_pm_domain *dev_to_genpd(struct device *dev) +struct generic_pm_domain *dev_to_genpd(struct device *dev) { if (IS_ERR_OR_NULL(dev->pm_domain)) return ERR_PTR(-EINVAL); @@ -436,6 +436,7 @@ static void genpd_power_off_work_fn(struct work_struct *work) static int pm_genpd_runtime_suspend(struct device *dev) { struct generic_pm_domain *genpd; + bool (*stop_ok)(struct device *__dev); int ret; dev_dbg(dev, "%s()\n", __func__); @@ -446,10 +447,17 @@ static int pm_genpd_runtime_suspend(struct device *dev) might_sleep_if(!genpd->dev_irq_safe); + stop_ok = genpd->gov ? genpd->gov->stop_ok : NULL; + if (stop_ok && !stop_ok(dev)) + return -EBUSY; + ret = genpd_stop_dev(genpd, dev); if (ret) return ret; + pm_runtime_update_max_time_suspended(dev, + dev_gpd_data(dev)->td.start_latency_ns); + /* * If power.irq_safe is set, this routine will be run with interrupts * off, so it can't use mutexes. @@ -1048,11 +1056,13 @@ static void pm_genpd_complete(struct device *dev) #endif /* CONFIG_PM_SLEEP */ /** - * pm_genpd_add_device - Add a device to an I/O PM domain. + * __pm_genpd_add_device - Add a device to an I/O PM domain. * @genpd: PM domain to add the device to. * @dev: Device to be added. + * @td: Set of PM QoS timing parameters to attach to the device. */ -int pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev) +int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev, + struct gpd_timing_data *td) { struct generic_pm_domain_data *gpd_data; struct pm_domain_data *pdd; @@ -1095,6 +1105,8 @@ int pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev) gpd_data->base.dev = dev; gpd_data->need_restore = false; list_add_tail(&gpd_data->base.list_node, &genpd->dev_list); + if (td) + gpd_data->td = *td; out: genpd_release_lock(genpd); @@ -1255,8 +1267,10 @@ int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd, * pm_genpd_add_callbacks - Add PM domain callbacks to a given device. * @dev: Device to add the callbacks to. * @ops: Set of callbacks to add. + * @td: Timing data to add to the device along with the callbacks (optional). */ -int pm_genpd_add_callbacks(struct device *dev, struct gpd_dev_ops *ops) +int pm_genpd_add_callbacks(struct device *dev, struct gpd_dev_ops *ops, + struct gpd_timing_data *td) { struct pm_domain_data *pdd; int ret = 0; @@ -1272,6 +1286,8 @@ int pm_genpd_add_callbacks(struct device *dev, struct gpd_dev_ops *ops) struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd); gpd_data->ops = *ops; + if (td) + gpd_data->td = *td; } else { ret = -EINVAL; } @@ -1284,10 +1300,11 @@ int pm_genpd_add_callbacks(struct device *dev, struct gpd_dev_ops *ops) EXPORT_SYMBOL_GPL(pm_genpd_add_callbacks); /** - * pm_genpd_remove_callbacks - Remove PM domain callbacks from a given device. + * __pm_genpd_remove_callbacks - Remove PM domain callbacks from a given device. * @dev: Device to remove the callbacks from. + * @clear_td: If set, clear the device's timing data too. */ -int pm_genpd_remove_callbacks(struct device *dev) +int __pm_genpd_remove_callbacks(struct device *dev, bool clear_td) { struct pm_domain_data *pdd; int ret = 0; @@ -1303,6 +1320,8 @@ int pm_genpd_remove_callbacks(struct device *dev) struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd); gpd_data->ops = (struct gpd_dev_ops){ 0 }; + if (clear_td) + gpd_data->td = (struct gpd_timing_data){ 0 }; } else { ret = -EINVAL; } @@ -1312,7 +1331,7 @@ int pm_genpd_remove_callbacks(struct device *dev) return ret; } -EXPORT_SYMBOL_GPL(pm_genpd_remove_callbacks); +EXPORT_SYMBOL_GPL(__pm_genpd_remove_callbacks); /* Default device callbacks for generic PM domains. */ diff --git a/drivers/base/power/domain_governor.c b/drivers/base/power/domain_governor.c new file mode 100644 index 000000000000..97b21c10c496 --- /dev/null +++ b/drivers/base/power/domain_governor.c @@ -0,0 +1,33 @@ +/* + * drivers/base/power/domain_governor.c - Governors for device PM domains. + * + * Copyright (C) 2011 Rafael J. Wysocki , Renesas Electronics Corp. + * + * This file is released under the GPLv2. + */ + +#include +#include +#include +#include + +/** + * default_stop_ok - Default PM domain governor routine for stopping devices. + * @dev: Device to check. + */ +bool default_stop_ok(struct device *dev) +{ + struct gpd_timing_data *td = &dev_gpd_data(dev)->td; + + dev_dbg(dev, "%s()\n", __func__); + + if (dev->power.max_time_suspended_ns < 0 || td->break_even_ns == 0) + return true; + + return td->stop_latency_ns + td->start_latency_ns < td->break_even_ns + && td->break_even_ns < dev->power.max_time_suspended_ns; +} + +struct dev_power_governor simple_qos_governor = { + .stop_ok = default_stop_ok, +}; diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index 10a197dce07e..f6745c213a57 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -21,6 +21,7 @@ enum gpd_status { struct dev_power_governor { bool (*power_down_ok)(struct dev_pm_domain *domain); + bool (*stop_ok)(struct device *dev); }; struct gpd_dev_ops { @@ -76,9 +77,16 @@ struct gpd_link { struct list_head slave_node; }; +struct gpd_timing_data { + s64 stop_latency_ns; + s64 start_latency_ns; + s64 break_even_ns; +}; + struct generic_pm_domain_data { struct pm_domain_data base; struct gpd_dev_ops ops; + struct gpd_timing_data td; bool need_restore; }; @@ -93,20 +101,48 @@ static inline struct generic_pm_domain_data *dev_gpd_data(struct device *dev) return to_gpd_data(dev->power.subsys_data->domain_data); } -extern int pm_genpd_add_device(struct generic_pm_domain *genpd, - struct device *dev); +extern struct dev_power_governor simple_qos_governor; + +extern struct generic_pm_domain *dev_to_genpd(struct device *dev); +extern int __pm_genpd_add_device(struct generic_pm_domain *genpd, + struct device *dev, + struct gpd_timing_data *td); + +static inline int pm_genpd_add_device(struct generic_pm_domain *genpd, + struct device *dev) +{ + return __pm_genpd_add_device(genpd, dev, NULL); +} + extern int pm_genpd_remove_device(struct generic_pm_domain *genpd, struct device *dev); extern int pm_genpd_add_subdomain(struct generic_pm_domain *genpd, struct generic_pm_domain *new_subdomain); extern int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd, struct generic_pm_domain *target); -extern int pm_genpd_add_callbacks(struct device *dev, struct gpd_dev_ops *ops); -extern int pm_genpd_remove_callbacks(struct device *dev); +extern int pm_genpd_add_callbacks(struct device *dev, + struct gpd_dev_ops *ops, + struct gpd_timing_data *td); +extern int __pm_genpd_remove_callbacks(struct device *dev, bool clear_td); extern void pm_genpd_init(struct generic_pm_domain *genpd, struct dev_power_governor *gov, bool is_off); + extern int pm_genpd_poweron(struct generic_pm_domain *genpd); + +extern bool default_stop_ok(struct device *dev); + #else + +static inline struct generic_pm_domain *dev_to_genpd(struct device *dev) +{ + return ERR_PTR(-ENOSYS); +} +static inline int __pm_genpd_add_device(struct generic_pm_domain *genpd, + struct device *dev, + struct gpd_timing_data *td) +{ + return -ENOSYS; +} static inline int pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev) { @@ -128,22 +164,33 @@ static inline int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd, return -ENOSYS; } static inline int pm_genpd_add_callbacks(struct device *dev, - struct gpd_dev_ops *ops) + struct gpd_dev_ops *ops, + struct gpd_timing_data *td) { return -ENOSYS; } -static inline int pm_genpd_remove_callbacks(struct device *dev) +static inline int __pm_genpd_remove_callbacks(struct device *dev, bool clear_td) { return -ENOSYS; } -static inline void pm_genpd_init(struct generic_pm_domain *genpd, - struct dev_power_governor *gov, bool is_off) {} +static inline void pm_genpd_init(struct generic_pm_domain *genpd, bool is_off) +{ +} static inline int pm_genpd_poweron(struct generic_pm_domain *genpd) { return -ENOSYS; } +static inline bool default_stop_ok(struct device *dev) +{ + return false; +} #endif +static inline int pm_genpd_remove_callbacks(struct device *dev) +{ + return __pm_genpd_remove_callbacks(dev, true); +} + #ifdef CONFIG_PM_GENERIC_DOMAINS_RUNTIME extern void genpd_queue_power_off_work(struct generic_pm_domain *genpd); extern void pm_genpd_poweroff_unused(void); -- cgit v1.2.3-59-g8ed1b From 221e9b58380abdd6c05e11b4538597e2586ee141 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 1 Dec 2011 00:02:10 +0100 Subject: PM / Domains: Add default power off governor function (v4) Add a function deciding whether or not a given PM domain should be powered off on the basis of the PM QoS constraints of devices belonging to it and their PM QoS timing data. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/domain.c | 12 ++++ drivers/base/power/domain_governor.c | 110 +++++++++++++++++++++++++++++++++++ include/linux/pm_domain.h | 7 +++ 3 files changed, 129 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 3af9f5a71ad5..91896194e76b 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -398,6 +398,17 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd) } genpd->status = GPD_STATE_POWER_OFF; + genpd->power_off_time = ktime_get(); + + /* Update PM QoS information for devices in the domain. */ + list_for_each_entry_reverse(pdd, &genpd->dev_list, list_node) { + struct gpd_timing_data *td = &to_gpd_data(pdd)->td; + + pm_runtime_update_max_time_suspended(pdd->dev, + td->start_latency_ns + + td->restore_state_latency_ns + + genpd->power_on_latency_ns); + } list_for_each_entry(link, &genpd->slave_links, slave_node) { genpd_sd_counter_dec(link->master); @@ -1487,6 +1498,7 @@ void pm_genpd_init(struct generic_pm_domain *genpd, genpd->resume_count = 0; genpd->device_count = 0; genpd->suspended_count = 0; + genpd->max_off_time_ns = -1; genpd->domain.ops.runtime_suspend = pm_genpd_runtime_suspend; genpd->domain.ops.runtime_resume = pm_genpd_runtime_resume; genpd->domain.ops.runtime_idle = pm_generic_runtime_idle; diff --git a/drivers/base/power/domain_governor.c b/drivers/base/power/domain_governor.c index 97b21c10c496..da78540e9b40 100644 --- a/drivers/base/power/domain_governor.c +++ b/drivers/base/power/domain_governor.c @@ -10,6 +10,7 @@ #include #include #include +#include /** * default_stop_ok - Default PM domain governor routine for stopping devices. @@ -28,6 +29,115 @@ bool default_stop_ok(struct device *dev) && td->break_even_ns < dev->power.max_time_suspended_ns; } +/** + * default_power_down_ok - Default generic PM domain power off governor routine. + * @pd: PM domain to check. + * + * This routine must be executed under the PM domain's lock. + */ +static bool default_power_down_ok(struct dev_pm_domain *pd) +{ + struct generic_pm_domain *genpd = pd_to_genpd(pd); + struct gpd_link *link; + struct pm_domain_data *pdd; + s64 min_dev_off_time_ns; + s64 off_on_time_ns; + ktime_t time_now = ktime_get(); + + off_on_time_ns = genpd->power_off_latency_ns + + genpd->power_on_latency_ns; + /* + * It doesn't make sense to remove power from the domain if saving + * the state of all devices in it and the power off/power on operations + * take too much time. + * + * All devices in this domain have been stopped already at this point. + */ + list_for_each_entry(pdd, &genpd->dev_list, list_node) { + if (pdd->dev->driver) + off_on_time_ns += + to_gpd_data(pdd)->td.save_state_latency_ns; + } + + /* + * Check if subdomains can be off for enough time. + * + * All subdomains have been powered off already at this point. + */ + list_for_each_entry(link, &genpd->master_links, master_node) { + struct generic_pm_domain *sd = link->slave; + s64 sd_max_off_ns = sd->max_off_time_ns; + + if (sd_max_off_ns < 0) + continue; + + sd_max_off_ns -= ktime_to_ns(ktime_sub(time_now, + sd->power_off_time)); + /* + * Check if the subdomain is allowed to be off long enough for + * the current domain to turn off and on (that's how much time + * it will have to wait worst case). + */ + if (sd_max_off_ns <= off_on_time_ns) + return false; + } + + /* + * Check if the devices in the domain can be off enough time. + */ + min_dev_off_time_ns = -1; + list_for_each_entry(pdd, &genpd->dev_list, list_node) { + struct gpd_timing_data *td; + struct device *dev = pdd->dev; + s64 dev_off_time_ns; + + if (!dev->driver || dev->power.max_time_suspended_ns < 0) + continue; + + td = &to_gpd_data(pdd)->td; + dev_off_time_ns = dev->power.max_time_suspended_ns - + (td->start_latency_ns + td->restore_state_latency_ns + + ktime_to_ns(ktime_sub(time_now, + dev->power.suspend_time))); + if (dev_off_time_ns <= off_on_time_ns) + return false; + + if (min_dev_off_time_ns > dev_off_time_ns + || min_dev_off_time_ns < 0) + min_dev_off_time_ns = dev_off_time_ns; + } + + if (min_dev_off_time_ns < 0) { + /* + * There are no latency constraints, so the domain can spend + * arbitrary time in the "off" state. + */ + genpd->max_off_time_ns = -1; + return true; + } + + /* + * The difference between the computed minimum delta and the time needed + * to turn the domain on is the maximum theoretical time this domain can + * spend in the "off" state. + */ + min_dev_off_time_ns -= genpd->power_on_latency_ns; + + /* + * If the difference between the computed minimum delta and the time + * needed to turn the domain off and back on on is smaller than the + * domain's power break even time, removing power from the domain is not + * worth it. + */ + if (genpd->break_even_ns > + min_dev_off_time_ns - genpd->power_off_latency_ns) + return false; + + genpd->max_off_time_ns = min_dev_off_time_ns; + return true; +} + struct dev_power_governor simple_qos_governor = { .stop_ok = default_stop_ok, + .power_down_ok = default_power_down_ok, }; diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index f6745c213a57..cc1a2450ff7b 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -61,8 +61,13 @@ struct generic_pm_domain { bool suspend_power_off; /* Power status before system suspend */ bool dev_irq_safe; /* Device callbacks are IRQ-safe */ int (*power_off)(struct generic_pm_domain *domain); + s64 power_off_latency_ns; int (*power_on)(struct generic_pm_domain *domain); + s64 power_on_latency_ns; struct gpd_dev_ops dev_ops; + s64 break_even_ns; /* Power break even for the entire domain. */ + s64 max_off_time_ns; /* Maximum allowed "suspended" time. */ + ktime_t power_off_time; }; static inline struct generic_pm_domain *pd_to_genpd(struct dev_pm_domain *pd) @@ -80,6 +85,8 @@ struct gpd_link { struct gpd_timing_data { s64 stop_latency_ns; s64 start_latency_ns; + s64 save_state_latency_ns; + s64 restore_state_latency_ns; s64 break_even_ns; }; -- cgit v1.2.3-59-g8ed1b From 0140d8bd47f798d55c3720f7fcade9e50929a5e5 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 1 Dec 2011 00:02:17 +0100 Subject: PM / Domains: Automatically update overoptimistic latency information Measure the time of execution of the .stop(), .start(), .save_state() and .restore_state() PM domain device callbacks and if the result is greater than the corresponding latency value stored in the device's struct generic_pm_domain_data object, replace the inaccurate value with the measured time. Do analogously for the PM domains' .power_off() and .power_off() callbacks. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/domain.c | 43 +++++++++++++++++++++++++++++++++++++++---- 1 file changed, 39 insertions(+), 4 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 91896194e76b..5a8d67d51f0e 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -33,6 +33,20 @@ __ret; \ }) +#define GENPD_DEV_TIMED_CALLBACK(genpd, type, callback, dev, field, name) \ +({ \ + ktime_t __start = ktime_get(); \ + type __retval = GENPD_DEV_CALLBACK(genpd, type, callback, dev); \ + s64 __elapsed = ktime_to_ns(ktime_sub(ktime_get(), __start)); \ + struct generic_pm_domain_data *__gpd_data = dev_gpd_data(dev); \ + if (__elapsed > __gpd_data->td.field) { \ + __gpd_data->td.field = __elapsed; \ + dev_warn(dev, name " latency exceeded, new value %lld ns\n", \ + __elapsed); \ + } \ + __retval; \ +}) + static LIST_HEAD(gpd_list); static DEFINE_MUTEX(gpd_list_lock); @@ -48,22 +62,27 @@ struct generic_pm_domain *dev_to_genpd(struct device *dev) static int genpd_stop_dev(struct generic_pm_domain *genpd, struct device *dev) { - return GENPD_DEV_CALLBACK(genpd, int, stop, dev); + return GENPD_DEV_TIMED_CALLBACK(genpd, int, stop, dev, + stop_latency_ns, "stop"); } static int genpd_start_dev(struct generic_pm_domain *genpd, struct device *dev) { - return GENPD_DEV_CALLBACK(genpd, int, start, dev); + return GENPD_DEV_TIMED_CALLBACK(genpd, int, start, dev, + start_latency_ns, "start"); } static int genpd_save_dev(struct generic_pm_domain *genpd, struct device *dev) { - return GENPD_DEV_CALLBACK(genpd, int, save_state, dev); + return GENPD_DEV_TIMED_CALLBACK(genpd, int, save_state, dev, + save_state_latency_ns, "state save"); } static int genpd_restore_dev(struct generic_pm_domain *genpd, struct device *dev) { - return GENPD_DEV_CALLBACK(genpd, int, restore_state, dev); + return GENPD_DEV_TIMED_CALLBACK(genpd, int, restore_state, dev, + restore_state_latency_ns, + "state restore"); } static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd) @@ -182,9 +201,16 @@ int __pm_genpd_poweron(struct generic_pm_domain *genpd) } if (genpd->power_on) { + ktime_t time_start = ktime_get(); + s64 elapsed_ns; + ret = genpd->power_on(genpd); if (ret) goto err; + + elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start)); + if (elapsed_ns > genpd->power_on_latency_ns) + genpd->power_on_latency_ns = elapsed_ns; } genpd_set_active(genpd); @@ -377,11 +403,16 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd) } if (genpd->power_off) { + ktime_t time_start; + s64 elapsed_ns; + if (atomic_read(&genpd->sd_count) > 0) { ret = -EBUSY; goto out; } + time_start = ktime_get(); + /* * If sd_count > 0 at this point, one of the subdomains hasn't * managed to call pm_genpd_poweron() for the master yet after @@ -395,6 +426,10 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd) genpd_set_active(genpd); goto out; } + + elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start)); + if (elapsed_ns > genpd->power_off_latency_ns) + genpd->power_off_latency_ns = elapsed_ns; } genpd->status = GPD_STATE_POWER_OFF; -- cgit v1.2.3-59-g8ed1b From 0c6aebe31861c470c8cfbfdfdfd72d1369a6440b Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sat, 3 Dec 2011 00:23:43 +0100 Subject: PM / Sleep: Unify diagnostic messages from device suspend/resume Make pm_op() and pm_noirq_op() use the same helper function for running callbacks, which will cause them to use the same format of diagnostic messages. This also reduces the complexity and size of the code quite a bit. Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman --- drivers/base/power/main.c | 128 +++++++++++++--------------------------------- 1 file changed, 35 insertions(+), 93 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 406f82c344fa..b570189d4f2d 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -164,8 +164,9 @@ static ktime_t initcall_debug_start(struct device *dev) ktime_t calltime = ktime_set(0, 0); if (initcall_debug) { - pr_info("calling %s+ @ %i\n", - dev_name(dev), task_pid_nr(current)); + pr_info("calling %s+ @ %i, parent: %s\n", + dev_name(dev), task_pid_nr(current), + dev->parent ? dev_name(dev->parent) : "none"); calltime = ktime_get(); } @@ -210,6 +211,24 @@ static void dpm_wait_for_children(struct device *dev, bool async) device_for_each_child(dev, &async, dpm_wait_fn); } +static int dpm_run_callback(struct device *dev, int (*cb)(struct device *)) +{ + ktime_t calltime; + int error; + + if (!cb) + return 0; + + calltime = initcall_debug_start(dev); + + error = cb(dev); + suspend_report_result(cb, error); + + initcall_debug_report(dev, calltime, error); + + return error; +} + /** * pm_op - Execute the PM operation appropriate for given PM event. * @dev: Device to handle. @@ -221,59 +240,36 @@ static int pm_op(struct device *dev, pm_message_t state) { int error = 0; - ktime_t calltime; - - calltime = initcall_debug_start(dev); switch (state.event) { #ifdef CONFIG_SUSPEND case PM_EVENT_SUSPEND: - if (ops->suspend) { - error = ops->suspend(dev); - suspend_report_result(ops->suspend, error); - } + error = dpm_run_callback(dev, ops->suspend); break; case PM_EVENT_RESUME: - if (ops->resume) { - error = ops->resume(dev); - suspend_report_result(ops->resume, error); - } + error = dpm_run_callback(dev, ops->resume); break; #endif /* CONFIG_SUSPEND */ #ifdef CONFIG_HIBERNATE_CALLBACKS case PM_EVENT_FREEZE: case PM_EVENT_QUIESCE: - if (ops->freeze) { - error = ops->freeze(dev); - suspend_report_result(ops->freeze, error); - } + error = dpm_run_callback(dev, ops->freeze); break; case PM_EVENT_HIBERNATE: - if (ops->poweroff) { - error = ops->poweroff(dev); - suspend_report_result(ops->poweroff, error); - } + error = dpm_run_callback(dev, ops->poweroff); break; case PM_EVENT_THAW: case PM_EVENT_RECOVER: - if (ops->thaw) { - error = ops->thaw(dev); - suspend_report_result(ops->thaw, error); - } + error = dpm_run_callback(dev, ops->thaw); break; case PM_EVENT_RESTORE: - if (ops->restore) { - error = ops->restore(dev); - suspend_report_result(ops->restore, error); - } + error = dpm_run_callback(dev, ops->restore); break; #endif /* CONFIG_HIBERNATE_CALLBACKS */ default: error = -EINVAL; } - initcall_debug_report(dev, calltime, error); - return error; } @@ -291,70 +287,36 @@ static int pm_noirq_op(struct device *dev, pm_message_t state) { int error = 0; - ktime_t calltime = ktime_set(0, 0), delta, rettime; - - if (initcall_debug) { - pr_info("calling %s+ @ %i, parent: %s\n", - dev_name(dev), task_pid_nr(current), - dev->parent ? dev_name(dev->parent) : "none"); - calltime = ktime_get(); - } switch (state.event) { #ifdef CONFIG_SUSPEND case PM_EVENT_SUSPEND: - if (ops->suspend_noirq) { - error = ops->suspend_noirq(dev); - suspend_report_result(ops->suspend_noirq, error); - } + error = dpm_run_callback(dev, ops->suspend_noirq); break; case PM_EVENT_RESUME: - if (ops->resume_noirq) { - error = ops->resume_noirq(dev); - suspend_report_result(ops->resume_noirq, error); - } + error = dpm_run_callback(dev, ops->resume_noirq); break; #endif /* CONFIG_SUSPEND */ #ifdef CONFIG_HIBERNATE_CALLBACKS case PM_EVENT_FREEZE: case PM_EVENT_QUIESCE: - if (ops->freeze_noirq) { - error = ops->freeze_noirq(dev); - suspend_report_result(ops->freeze_noirq, error); - } + error = dpm_run_callback(dev, ops->freeze_noirq); break; case PM_EVENT_HIBERNATE: - if (ops->poweroff_noirq) { - error = ops->poweroff_noirq(dev); - suspend_report_result(ops->poweroff_noirq, error); - } + error = dpm_run_callback(dev, ops->poweroff_noirq); break; case PM_EVENT_THAW: case PM_EVENT_RECOVER: - if (ops->thaw_noirq) { - error = ops->thaw_noirq(dev); - suspend_report_result(ops->thaw_noirq, error); - } + error = dpm_run_callback(dev, ops->thaw_noirq); break; case PM_EVENT_RESTORE: - if (ops->restore_noirq) { - error = ops->restore_noirq(dev); - suspend_report_result(ops->restore_noirq, error); - } + error = dpm_run_callback(dev, ops->restore_noirq); break; #endif /* CONFIG_HIBERNATE_CALLBACKS */ default: error = -EINVAL; } - if (initcall_debug) { - rettime = ktime_get(); - delta = ktime_sub(rettime, calltime); - printk("initcall %s_i+ returned %d after %Ld usecs\n", - dev_name(dev), error, - (unsigned long long)ktime_to_ns(delta) >> 10); - } - return error; } @@ -485,26 +447,6 @@ void dpm_resume_noirq(pm_message_t state) } EXPORT_SYMBOL_GPL(dpm_resume_noirq); -/** - * legacy_resume - Execute a legacy (bus or class) resume callback for device. - * @dev: Device to resume. - * @cb: Resume callback to execute. - */ -static int legacy_resume(struct device *dev, int (*cb)(struct device *dev)) -{ - int error; - ktime_t calltime; - - calltime = initcall_debug_start(dev); - - error = cb(dev); - suspend_report_result(cb, error); - - initcall_debug_report(dev, calltime, error); - - return error; -} - /** * device_resume - Execute "resume" callbacks for given device. * @dev: Device to handle. @@ -553,7 +495,7 @@ static int device_resume(struct device *dev, pm_message_t state, bool async) goto End; } else if (dev->class->resume) { pm_dev_dbg(dev, state, "legacy class "); - error = legacy_resume(dev, dev->class->resume); + error = dpm_run_callback(dev, dev->class->resume); goto End; } } @@ -564,7 +506,7 @@ static int device_resume(struct device *dev, pm_message_t state, bool async) error = pm_op(dev, dev->bus->pm, state); } else if (dev->bus->resume) { pm_dev_dbg(dev, state, "legacy "); - error = legacy_resume(dev, dev->bus->resume); + error = dpm_run_callback(dev, dev->bus->resume); } } -- cgit v1.2.3-59-g8ed1b From e84b2c202771bbd538866207efcb1f7dbab8045b Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 6 Dec 2011 22:19:54 +0100 Subject: PM / Domains: Make it possible to assign names to generic PM domains Add a name member pointer to struct generic_pm_domain and use it in diagnostic messages regarding the domain power-off and power-on latencies. Update the ARM shmobile SH7372 code to assign names to the PM domains used by it. Signed-off-by: Rafael J. Wysocki Acked-by: Magnus Damm --- arch/arm/mach-shmobile/pm-sh7372.c | 16 ++++++++++++---- drivers/base/power/domain.c | 14 ++++++++++++-- include/linux/pm_domain.h | 1 + 3 files changed, 25 insertions(+), 6 deletions(-) (limited to 'drivers/base') diff --git a/arch/arm/mach-shmobile/pm-sh7372.c b/arch/arm/mach-shmobile/pm-sh7372.c index adf1765e69c6..8d9ea8924ed3 100644 --- a/arch/arm/mach-shmobile/pm-sh7372.c +++ b/arch/arm/mach-shmobile/pm-sh7372.c @@ -101,8 +101,8 @@ static int pd_power_down(struct generic_pm_domain *genpd) } if (!sh7372_pd->no_debug) - pr_debug("sh7372 power domain down 0x%08x -> PSTR = 0x%08x\n", - mask, __raw_readl(PSTR)); + pr_debug("%s: Power off, 0x%08x -> PSTR = 0x%08x\n", + genpd->name, mask, __raw_readl(PSTR)); return 0; } @@ -133,8 +133,8 @@ static int __pd_power_up(struct sh7372_pm_domain *sh7372_pd, bool do_resume) ret = -EIO; if (!sh7372_pd->no_debug) - pr_debug("sh7372 power domain up 0x%08x -> PSTR = 0x%08x\n", - mask, __raw_readl(PSTR)); + pr_debug("%s: Power on, 0x%08x -> PSTR = 0x%08x\n", + sh7372_pd->genpd.name, mask, __raw_readl(PSTR)); out: if (ret == 0 && sh7372_pd->resume && do_resume) @@ -233,18 +233,22 @@ void sh7372_pm_add_subdomain(struct sh7372_pm_domain *sh7372_pd, } struct sh7372_pm_domain sh7372_a4lc = { + .genpd.name = "A4LC", .bit_shift = 1, }; struct sh7372_pm_domain sh7372_a4mp = { + .genpd.name = "A4MP", .bit_shift = 2, }; struct sh7372_pm_domain sh7372_d4 = { + .genpd.name = "D4", .bit_shift = 3, }; struct sh7372_pm_domain sh7372_a4r = { + .genpd.name = "A4R", .bit_shift = 5, .gov = &sh7372_always_on_gov, .suspend = sh7372_a4r_suspend, @@ -253,14 +257,17 @@ struct sh7372_pm_domain sh7372_a4r = { }; struct sh7372_pm_domain sh7372_a3rv = { + .genpd.name = "A3RV", .bit_shift = 6, }; struct sh7372_pm_domain sh7372_a3ri = { + .genpd.name = "A3RI", .bit_shift = 8, }; struct sh7372_pm_domain sh7372_a3sp = { + .genpd.name = "A3SP", .bit_shift = 11, .gov = &sh7372_always_on_gov, .no_debug = true, @@ -275,6 +282,7 @@ static void sh7372_a3sp_init(void) } struct sh7372_pm_domain sh7372_a3sg = { + .genpd.name = "A3SG", .bit_shift = 13, }; diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 5a8d67d51f0e..ad6ba2e04677 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -209,8 +209,13 @@ int __pm_genpd_poweron(struct generic_pm_domain *genpd) goto err; elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start)); - if (elapsed_ns > genpd->power_on_latency_ns) + if (elapsed_ns > genpd->power_on_latency_ns) { genpd->power_on_latency_ns = elapsed_ns; + if (genpd->name) + pr_warning("%s: Power-on latency exceeded, " + "new value %lld ns\n", genpd->name, + elapsed_ns); + } } genpd_set_active(genpd); @@ -428,8 +433,13 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd) } elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start)); - if (elapsed_ns > genpd->power_off_latency_ns) + if (elapsed_ns > genpd->power_off_latency_ns) { genpd->power_off_latency_ns = elapsed_ns; + if (genpd->name) + pr_warning("%s: Power-off latency exceeded, " + "new value %lld ns\n", genpd->name, + elapsed_ns); + } } genpd->status = GPD_STATE_POWER_OFF; diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index fbb81bc5065a..fb809b904891 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -50,6 +50,7 @@ struct generic_pm_domain { struct mutex lock; struct dev_power_governor *gov; struct work_struct power_off_work; + char *name; unsigned int in_progress; /* Number of devices being suspended now */ atomic_t sd_count; /* Number of subdomains with power "on" */ enum gpd_status status; /* Current state of the domain */ -- cgit v1.2.3-59-g8ed1b From c9914854b4ca339e511d052ce3a1a441ef15b928 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 6 Dec 2011 23:16:47 +0100 Subject: PM / Domains: Fix default system suspend/resume operations Commit d23b9b00cdde5c93b914a172cecd57d5625fcd04 (PM / Domains: Rework system suspend callback routines (v2)) broke the system suspend and resume handling by devices belonging to generic PM domains, because it used freeze/thaw callbacks instead of suspend/resume ones and didn't initialize device callbacks for system suspend/resume properly at all. Fix those problems. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/domain.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index ad6ba2e04677..92e6a9048065 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -1435,7 +1435,7 @@ static int pm_genpd_default_restore_state(struct device *dev) */ static int pm_genpd_default_suspend(struct device *dev) { - int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.freeze; + int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.suspend; return cb ? cb(dev) : pm_generic_suspend(dev); } @@ -1446,7 +1446,7 @@ static int pm_genpd_default_suspend(struct device *dev) */ static int pm_genpd_default_suspend_late(struct device *dev) { - int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.freeze_late; + int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.suspend_late; return cb ? cb(dev) : pm_generic_suspend_noirq(dev); } @@ -1457,7 +1457,7 @@ static int pm_genpd_default_suspend_late(struct device *dev) */ static int pm_genpd_default_resume_early(struct device *dev) { - int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.thaw_early; + int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.resume_early; return cb ? cb(dev) : pm_generic_resume_noirq(dev); } @@ -1468,7 +1468,7 @@ static int pm_genpd_default_resume_early(struct device *dev) */ static int pm_genpd_default_resume(struct device *dev) { - int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.thaw; + int (*cb)(struct device *__dev) = dev_gpd_data(dev)->ops.resume; return cb ? cb(dev) : pm_generic_resume(dev); } @@ -1563,10 +1563,10 @@ void pm_genpd_init(struct generic_pm_domain *genpd, genpd->domain.ops.complete = pm_genpd_complete; genpd->dev_ops.save_state = pm_genpd_default_save_state; genpd->dev_ops.restore_state = pm_genpd_default_restore_state; - genpd->dev_ops.freeze = pm_genpd_default_suspend; - genpd->dev_ops.freeze_late = pm_genpd_default_suspend_late; - genpd->dev_ops.thaw_early = pm_genpd_default_resume_early; - genpd->dev_ops.thaw = pm_genpd_default_resume; + genpd->dev_ops.suspend = pm_genpd_default_suspend; + genpd->dev_ops.suspend_late = pm_genpd_default_suspend_late; + genpd->dev_ops.resume_early = pm_genpd_default_resume_early; + genpd->dev_ops.resume = pm_genpd_default_resume; genpd->dev_ops.freeze = pm_genpd_default_freeze; genpd->dev_ops.freeze_late = pm_genpd_default_freeze_late; genpd->dev_ops.thaw_early = pm_genpd_default_thaw_early; -- cgit v1.2.3-59-g8ed1b From 925b44a273aa8c4c23c006c1228aacd538eead09 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Thu, 8 Dec 2011 23:27:28 +0100 Subject: PM / Domains: Provide an always on power domain governor Since systems are likely to have power domains that can't be turned off for various reasons at least temporarily while implementing power domain support provide a default governor which will always refuse to power off the domain, saving platforms having to implement their own. Since the code is so tiny don't bother with a Kconfig symbol for it. Signed-off-by: Mark Brown Signed-off-by: Rafael J. Wysocki --- drivers/base/power/domain_governor.c | 13 +++++++++++++ include/linux/pm_domain.h | 2 ++ 2 files changed, 15 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/power/domain_governor.c b/drivers/base/power/domain_governor.c index da78540e9b40..51527ee92d10 100644 --- a/drivers/base/power/domain_governor.c +++ b/drivers/base/power/domain_governor.c @@ -141,3 +141,16 @@ struct dev_power_governor simple_qos_governor = { .stop_ok = default_stop_ok, .power_down_ok = default_power_down_ok, }; + +static bool always_on_power_down_ok(struct dev_pm_domain *domain) +{ + return false; +} + +/** + * pm_genpd_gov_always_on - A governor implementing an always-on policy + */ +struct dev_power_governor pm_domain_always_on_gov = { + .power_down_ok = always_on_power_down_ok, + .stop_ok = default_stop_ok, +}; diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index fb809b904891..a03a0ad998b8 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -140,6 +140,7 @@ extern int pm_genpd_poweron(struct generic_pm_domain *genpd); extern bool default_stop_ok(struct device *dev); +extern struct dev_power_governor pm_domain_always_on_gov; #else static inline struct generic_pm_domain *dev_to_genpd(struct device *dev) @@ -193,6 +194,7 @@ static inline bool default_stop_ok(struct device *dev) { return false; } +#define pm_domain_always_on_gov NULL #endif static inline int pm_genpd_remove_callbacks(struct device *dev) -- cgit v1.2.3-59-g8ed1b From b298d289c79211508f11cb50749b0d1d54eb244a Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Fri, 9 Dec 2011 23:36:36 +0100 Subject: PM / Sleep: Fix freezer failures due to racy usermodehelper_is_disabled() Commit a144c6a (PM: Print a warning if firmware is requested when tasks are frozen) introduced usermodehelper_is_disabled() to warn and exit immediately if firmware is requested when usermodehelpers are disabled. However, it is racy. Consider the following scenario, currently used in drivers/base/firmware_class.c: ... if (usermodehelper_is_disabled()) goto out; /* Do actual work */ ... out: return err; Nothing prevents someone from disabling usermodehelpers just after the check in the 'if' condition, which means that it is quite possible to try doing the "actual work" with usermodehelpers disabled, leading to undesirable consequences. In particular, this race condition in _request_firmware() causes task freezing failures whenever suspend/hibernation is in progress because, it wrongly waits to get the firmware/microcode image from userspace when actually the usermodehelpers are disabled or userspace has been frozen. Some of the example scenarios that cause freezing failures due to this race are those that depend on userspace via request_firmware(), such as x86 microcode module initialization and microcode image reload. Previous discussions about this issue can be found at: http://thread.gmane.org/gmane.linux.kernel/1198291/focus=1200591 This patch adds proper synchronization to fix this issue. It is to be noted that this patchset fixes the freezing failures but doesn't remove the warnings. IOW, it does not attempt to add explicit synchronization to x86 microcode driver to avoid requesting microcode image at inopportune moments. Because, the warnings were introduced to highlight such cases, in the first place. And we need not silence the warnings, since we take care of the *real* problem (freezing failure) and hence, after that, the warnings are pretty harmless anyway. Signed-off-by: Srivatsa S. Bhat Signed-off-by: Rafael J. Wysocki --- drivers/base/firmware_class.c | 4 ++++ include/linux/kmod.h | 2 ++ kernel/kmod.c | 23 ++++++++++++++++++++++- 3 files changed, 28 insertions(+), 1 deletion(-) (limited to 'drivers/base') diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c index 06ed6b4e7df5..d5585da14c8a 100644 --- a/drivers/base/firmware_class.c +++ b/drivers/base/firmware_class.c @@ -534,6 +534,8 @@ static int _request_firmware(const struct firmware **firmware_p, return 0; } + read_lock_usermodehelper(); + if (WARN_ON(usermodehelper_is_disabled())) { dev_err(device, "firmware: %s will not be loaded\n", name); retval = -EBUSY; @@ -572,6 +574,8 @@ static int _request_firmware(const struct firmware **firmware_p, fw_destroy_instance(fw_priv); out: + read_unlock_usermodehelper(); + if (retval) { release_firmware(firmware); *firmware_p = NULL; diff --git a/include/linux/kmod.h b/include/linux/kmod.h index b16f65390734..722f477c4ef7 100644 --- a/include/linux/kmod.h +++ b/include/linux/kmod.h @@ -117,5 +117,7 @@ extern void usermodehelper_init(void); extern int usermodehelper_disable(void); extern void usermodehelper_enable(void); extern bool usermodehelper_is_disabled(void); +extern void read_lock_usermodehelper(void); +extern void read_unlock_usermodehelper(void); #endif /* __LINUX_KMOD_H__ */ diff --git a/kernel/kmod.c b/kernel/kmod.c index a4bea97c75b6..81b4a27261b2 100644 --- a/kernel/kmod.c +++ b/kernel/kmod.c @@ -36,6 +36,7 @@ #include #include #include +#include #include #include @@ -50,6 +51,7 @@ static struct workqueue_struct *khelper_wq; static kernel_cap_t usermodehelper_bset = CAP_FULL_SET; static kernel_cap_t usermodehelper_inheritable = CAP_FULL_SET; static DEFINE_SPINLOCK(umh_sysctl_lock); +static DECLARE_RWSEM(umhelper_sem); #ifdef CONFIG_MODULES @@ -275,6 +277,7 @@ static void __call_usermodehelper(struct work_struct *work) * If set, call_usermodehelper_exec() will exit immediately returning -EBUSY * (used for preventing user land processes from being created after the user * land has been frozen during a system-wide hibernation or suspend operation). + * Should always be manipulated under umhelper_sem acquired for write. */ static int usermodehelper_disabled = 1; @@ -293,6 +296,18 @@ static DECLARE_WAIT_QUEUE_HEAD(running_helpers_waitq); */ #define RUNNING_HELPERS_TIMEOUT (5 * HZ) +void read_lock_usermodehelper(void) +{ + down_read(&umhelper_sem); +} +EXPORT_SYMBOL_GPL(read_lock_usermodehelper); + +void read_unlock_usermodehelper(void) +{ + up_read(&umhelper_sem); +} +EXPORT_SYMBOL_GPL(read_unlock_usermodehelper); + /** * usermodehelper_disable - prevent new helpers from being started */ @@ -300,8 +315,10 @@ int usermodehelper_disable(void) { long retval; + down_write(&umhelper_sem); usermodehelper_disabled = 1; - smp_mb(); + up_write(&umhelper_sem); + /* * From now on call_usermodehelper_exec() won't start any new * helpers, so it is sufficient if running_helpers turns out to @@ -314,7 +331,9 @@ int usermodehelper_disable(void) if (retval) return 0; + down_write(&umhelper_sem); usermodehelper_disabled = 0; + up_write(&umhelper_sem); return -EAGAIN; } @@ -323,7 +342,9 @@ int usermodehelper_disable(void) */ void usermodehelper_enable(void) { + down_write(&umhelper_sem); usermodehelper_disabled = 0; + up_write(&umhelper_sem); } /** -- cgit v1.2.3-59-g8ed1b From 8ca6d9bcc8d33c592c0855b4b1481bc723ac7e85 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 15 Dec 2011 20:59:23 +0100 Subject: PM / Sleep: Simplify generic system suspend callbacks The pm_runtime_suspended() check in __pm_generic_call() doesn't really help and may cause problems to happen, because in some cases the system suspend callbacks need to be called even if the given device has been suspended by runtime PM. For example, if the device generally supports remote wakeup and is not enabled to wake up the system from sleep, it should be prevented from generating wakeup signals during system suspend and that has to be done by the suspend callbacks that the pm_runtime_suspended() check prevents from being executed. Similarly, it may not be a good idea to unconditionally change the runtime PM status of the device to 'active' in __pm_generic_resume(), because the driver may want to leave the device in the 'suspended' state, depending on what happened to it before the system suspend and whether or not it is enabled to wake up the system. For the above reasons, remove the pm_runtime_suspended() check from __pm_generic_call() and remove the code changing the device's runtime PM status from __pm_generic_resume(). Signed-off-by: Rafael J. Wysocki --- drivers/base/power/generic_ops.c | 24 ++++++------------------ 1 file changed, 6 insertions(+), 18 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/generic_ops.c b/drivers/base/power/generic_ops.c index 265a0ee3b49e..1b878b955c8a 100644 --- a/drivers/base/power/generic_ops.c +++ b/drivers/base/power/generic_ops.c @@ -97,16 +97,16 @@ int pm_generic_prepare(struct device *dev) * @event: PM transition of the system under way. * @bool: Whether or not this is the "noirq" stage. * - * If the device has not been suspended at run time, execute the - * suspend/freeze/poweroff/thaw callback provided by its driver, if defined, and - * return its error code. Otherwise, return zero. + * Execute the suspend/freeze/poweroff/thaw callback provided by the driver of + * @dev, if defined, and return its error code. Return 0 if the callback is + * not present. */ static int __pm_generic_call(struct device *dev, int event, bool noirq) { const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; int (*callback)(struct device *); - if (!pm || pm_runtime_suspended(dev)) + if (!pm) return 0; switch (event) { @@ -217,14 +217,12 @@ EXPORT_SYMBOL_GPL(pm_generic_thaw); * @bool: Whether or not this is the "noirq" stage. * * Execute the resume/resotre callback provided by the @dev's driver, if - * defined. If it returns 0, change the device's runtime PM status to 'active'. - * Return the callback's error code. + * defined, and return its error code. Return 0 if the callback is not present. */ static int __pm_generic_resume(struct device *dev, int event, bool noirq) { const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; int (*callback)(struct device *); - int ret; if (!pm) return 0; @@ -241,17 +239,7 @@ static int __pm_generic_resume(struct device *dev, int event, bool noirq) break; } - if (!callback) - return 0; - - ret = callback(dev); - if (!ret && !noirq && pm_runtime_enabled(dev)) { - pm_runtime_disable(dev); - pm_runtime_set_active(dev); - pm_runtime_enable(dev); - } - - return ret; + return callback ? callback(dev) : 0; } /** -- cgit v1.2.3-59-g8ed1b From 1eac8111e0763853266a171ce11214da3a347a0a Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 15 Dec 2011 20:59:30 +0100 Subject: PM / Sleep: Merge internal functions in generic_ops.c After the change that removed the code related to runtime PM from __pm_generic_call() and __pm_generic_resume() these two functions need not be separate any more, so merge them. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/generic_ops.c | 48 +++++++++------------------------------- 1 file changed, 11 insertions(+), 37 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/generic_ops.c b/drivers/base/power/generic_ops.c index 1b878b955c8a..5a5b154bc1e9 100644 --- a/drivers/base/power/generic_ops.c +++ b/drivers/base/power/generic_ops.c @@ -97,7 +97,7 @@ int pm_generic_prepare(struct device *dev) * @event: PM transition of the system under way. * @bool: Whether or not this is the "noirq" stage. * - * Execute the suspend/freeze/poweroff/thaw callback provided by the driver of + * Execute the PM callback corresponding to @event provided by the driver of * @dev, if defined, and return its error code. Return 0 if the callback is * not present. */ @@ -119,9 +119,15 @@ static int __pm_generic_call(struct device *dev, int event, bool noirq) case PM_EVENT_HIBERNATE: callback = noirq ? pm->poweroff_noirq : pm->poweroff; break; + case PM_EVENT_RESUME: + callback = noirq ? pm->resume_noirq : pm->resume; + break; case PM_EVENT_THAW: callback = noirq ? pm->thaw_noirq : pm->thaw; break; + case PM_EVENT_RESTORE: + callback = noirq ? pm->restore_noirq : pm->restore; + break; default: callback = NULL; break; @@ -210,45 +216,13 @@ int pm_generic_thaw(struct device *dev) } EXPORT_SYMBOL_GPL(pm_generic_thaw); -/** - * __pm_generic_resume - Generic resume/restore callback for subsystems. - * @dev: Device to handle. - * @event: PM transition of the system under way. - * @bool: Whether or not this is the "noirq" stage. - * - * Execute the resume/resotre callback provided by the @dev's driver, if - * defined, and return its error code. Return 0 if the callback is not present. - */ -static int __pm_generic_resume(struct device *dev, int event, bool noirq) -{ - const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; - int (*callback)(struct device *); - - if (!pm) - return 0; - - switch (event) { - case PM_EVENT_RESUME: - callback = noirq ? pm->resume_noirq : pm->resume; - break; - case PM_EVENT_RESTORE: - callback = noirq ? pm->restore_noirq : pm->restore; - break; - default: - callback = NULL; - break; - } - - return callback ? callback(dev) : 0; -} - /** * pm_generic_resume_noirq - Generic resume_noirq callback for subsystems. * @dev: Device to resume. */ int pm_generic_resume_noirq(struct device *dev) { - return __pm_generic_resume(dev, PM_EVENT_RESUME, true); + return __pm_generic_call(dev, PM_EVENT_RESUME, true); } EXPORT_SYMBOL_GPL(pm_generic_resume_noirq); @@ -258,7 +232,7 @@ EXPORT_SYMBOL_GPL(pm_generic_resume_noirq); */ int pm_generic_resume(struct device *dev) { - return __pm_generic_resume(dev, PM_EVENT_RESUME, false); + return __pm_generic_call(dev, PM_EVENT_RESUME, false); } EXPORT_SYMBOL_GPL(pm_generic_resume); @@ -268,7 +242,7 @@ EXPORT_SYMBOL_GPL(pm_generic_resume); */ int pm_generic_restore_noirq(struct device *dev) { - return __pm_generic_resume(dev, PM_EVENT_RESTORE, true); + return __pm_generic_call(dev, PM_EVENT_RESTORE, true); } EXPORT_SYMBOL_GPL(pm_generic_restore_noirq); @@ -278,7 +252,7 @@ EXPORT_SYMBOL_GPL(pm_generic_restore_noirq); */ int pm_generic_restore(struct device *dev) { - return __pm_generic_resume(dev, PM_EVENT_RESTORE, false); + return __pm_generic_call(dev, PM_EVENT_RESTORE, false); } EXPORT_SYMBOL_GPL(pm_generic_restore); -- cgit v1.2.3-59-g8ed1b From 9cf519d1c15fa05a538c2b3963c5f3903daf765a Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 18 Dec 2011 00:34:01 +0100 Subject: PM / Sleep: Make pm_op() and pm_noirq_op() return callback pointers Make the pm_op() and pm_noirq_op() functions return pointers to appropriate callbacks instead of executing those callbacks and returning their results. This change is required for a subsequent modification that will execute the corresponding driver callback if the subsystem callback returned by either pm_op(), or pm_noirq_op() is NULL. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/main.c | 197 ++++++++++++++++++++++------------------------ 1 file changed, 95 insertions(+), 102 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index b570189d4f2d..b5cef7e7de23 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -32,6 +32,8 @@ #include "../base.h" #include "power.h" +typedef int (*pm_callback_t)(struct device *); + /* * The entries in the dpm_list list are in a depth first order, simply * because children are guaranteed to be discovered after parents, and @@ -211,113 +213,70 @@ static void dpm_wait_for_children(struct device *dev, bool async) device_for_each_child(dev, &async, dpm_wait_fn); } -static int dpm_run_callback(struct device *dev, int (*cb)(struct device *)) -{ - ktime_t calltime; - int error; - - if (!cb) - return 0; - - calltime = initcall_debug_start(dev); - - error = cb(dev); - suspend_report_result(cb, error); - - initcall_debug_report(dev, calltime, error); - - return error; -} - /** - * pm_op - Execute the PM operation appropriate for given PM event. - * @dev: Device to handle. + * pm_op - Return the PM operation appropriate for given PM event. * @ops: PM operations to choose from. * @state: PM transition of the system being carried out. */ -static int pm_op(struct device *dev, - const struct dev_pm_ops *ops, - pm_message_t state) +static pm_callback_t pm_op(const struct dev_pm_ops *ops, pm_message_t state) { - int error = 0; - switch (state.event) { #ifdef CONFIG_SUSPEND case PM_EVENT_SUSPEND: - error = dpm_run_callback(dev, ops->suspend); - break; + return ops->suspend; case PM_EVENT_RESUME: - error = dpm_run_callback(dev, ops->resume); - break; + return ops->resume; #endif /* CONFIG_SUSPEND */ #ifdef CONFIG_HIBERNATE_CALLBACKS case PM_EVENT_FREEZE: case PM_EVENT_QUIESCE: - error = dpm_run_callback(dev, ops->freeze); - break; + return ops->freeze; case PM_EVENT_HIBERNATE: - error = dpm_run_callback(dev, ops->poweroff); - break; + return ops->poweroff; case PM_EVENT_THAW: case PM_EVENT_RECOVER: - error = dpm_run_callback(dev, ops->thaw); + return ops->thaw; break; case PM_EVENT_RESTORE: - error = dpm_run_callback(dev, ops->restore); - break; + return ops->restore; #endif /* CONFIG_HIBERNATE_CALLBACKS */ - default: - error = -EINVAL; } - return error; + return NULL; } /** - * pm_noirq_op - Execute the PM operation appropriate for given PM event. - * @dev: Device to handle. + * pm_noirq_op - Return the PM operation appropriate for given PM event. * @ops: PM operations to choose from. * @state: PM transition of the system being carried out. * * The driver of @dev will not receive interrupts while this function is being * executed. */ -static int pm_noirq_op(struct device *dev, - const struct dev_pm_ops *ops, - pm_message_t state) +static pm_callback_t pm_noirq_op(const struct dev_pm_ops *ops, pm_message_t state) { - int error = 0; - switch (state.event) { #ifdef CONFIG_SUSPEND case PM_EVENT_SUSPEND: - error = dpm_run_callback(dev, ops->suspend_noirq); - break; + return ops->suspend_noirq; case PM_EVENT_RESUME: - error = dpm_run_callback(dev, ops->resume_noirq); - break; + return ops->resume_noirq; #endif /* CONFIG_SUSPEND */ #ifdef CONFIG_HIBERNATE_CALLBACKS case PM_EVENT_FREEZE: case PM_EVENT_QUIESCE: - error = dpm_run_callback(dev, ops->freeze_noirq); - break; + return ops->freeze_noirq; case PM_EVENT_HIBERNATE: - error = dpm_run_callback(dev, ops->poweroff_noirq); - break; + return ops->poweroff_noirq; case PM_EVENT_THAW: case PM_EVENT_RECOVER: - error = dpm_run_callback(dev, ops->thaw_noirq); - break; + return ops->thaw_noirq; case PM_EVENT_RESTORE: - error = dpm_run_callback(dev, ops->restore_noirq); - break; + return ops->restore_noirq; #endif /* CONFIG_HIBERNATE_CALLBACKS */ - default: - error = -EINVAL; } - return error; + return NULL; } static char *pm_verb(int event) @@ -375,6 +334,26 @@ static void dpm_show_time(ktime_t starttime, pm_message_t state, char *info) usecs / USEC_PER_MSEC, usecs % USEC_PER_MSEC); } +static int dpm_run_callback(pm_callback_t cb, struct device *dev, + pm_message_t state, char *info) +{ + ktime_t calltime; + int error; + + if (!cb) + return 0; + + calltime = initcall_debug_start(dev); + + pm_dev_dbg(dev, state, info); + error = cb(dev); + suspend_report_result(cb, error); + + initcall_debug_report(dev, calltime, error); + + return error; +} + /*------------------------- Resume routines -------------------------*/ /** @@ -387,25 +366,29 @@ static void dpm_show_time(ktime_t starttime, pm_message_t state, char *info) */ static int device_resume_noirq(struct device *dev, pm_message_t state) { + pm_callback_t callback = NULL; + char *info = NULL; int error = 0; TRACE_DEVICE(dev); TRACE_RESUME(0); if (dev->pm_domain) { - pm_dev_dbg(dev, state, "EARLY power domain "); - error = pm_noirq_op(dev, &dev->pm_domain->ops, state); + info = "EARLY power domain "; + callback = pm_noirq_op(&dev->pm_domain->ops, state); } else if (dev->type && dev->type->pm) { - pm_dev_dbg(dev, state, "EARLY type "); - error = pm_noirq_op(dev, dev->type->pm, state); + info = "EARLY type "; + callback = pm_noirq_op(dev->type->pm, state); } else if (dev->class && dev->class->pm) { - pm_dev_dbg(dev, state, "EARLY class "); - error = pm_noirq_op(dev, dev->class->pm, state); + info = "EARLY class "; + callback = pm_noirq_op(dev->class->pm, state); } else if (dev->bus && dev->bus->pm) { - pm_dev_dbg(dev, state, "EARLY "); - error = pm_noirq_op(dev, dev->bus->pm, state); + info = "EARLY "; + callback = pm_noirq_op(dev->bus->pm, state); } + error = dpm_run_callback(callback, dev, state, info); + TRACE_RESUME(error); return error; } @@ -455,6 +438,8 @@ EXPORT_SYMBOL_GPL(dpm_resume_noirq); */ static int device_resume(struct device *dev, pm_message_t state, bool async) { + pm_callback_t callback = NULL; + char *info = NULL; int error = 0; bool put = false; @@ -477,40 +462,41 @@ static int device_resume(struct device *dev, pm_message_t state, bool async) put = true; if (dev->pm_domain) { - pm_dev_dbg(dev, state, "power domain "); - error = pm_op(dev, &dev->pm_domain->ops, state); + info = "power domain "; + callback = pm_op(&dev->pm_domain->ops, state); goto End; } if (dev->type && dev->type->pm) { - pm_dev_dbg(dev, state, "type "); - error = pm_op(dev, dev->type->pm, state); + info = "type "; + callback = pm_op(dev->type->pm, state); goto End; } if (dev->class) { if (dev->class->pm) { - pm_dev_dbg(dev, state, "class "); - error = pm_op(dev, dev->class->pm, state); + info = "class "; + callback = pm_op(dev->class->pm, state); goto End; } else if (dev->class->resume) { - pm_dev_dbg(dev, state, "legacy class "); - error = dpm_run_callback(dev, dev->class->resume); + info = "legacy class "; + callback = dev->class->resume; goto End; } } if (dev->bus) { if (dev->bus->pm) { - pm_dev_dbg(dev, state, ""); - error = pm_op(dev, dev->bus->pm, state); + info = ""; + callback = pm_op(dev->bus->pm, state); } else if (dev->bus->resume) { - pm_dev_dbg(dev, state, "legacy "); - error = dpm_run_callback(dev, dev->bus->resume); + info = "legacy "; + callback = dev->bus->resume; } } End: + error = dpm_run_callback(callback, dev, state, info); dev->power.is_suspended = false; Unlock: @@ -705,23 +691,24 @@ static pm_message_t resume_event(pm_message_t sleep_state) */ static int device_suspend_noirq(struct device *dev, pm_message_t state) { - int error = 0; + pm_callback_t callback = NULL; + char *info = NULL; if (dev->pm_domain) { - pm_dev_dbg(dev, state, "LATE power domain "); - error = pm_noirq_op(dev, &dev->pm_domain->ops, state); + info = "LATE power domain "; + callback = pm_noirq_op(&dev->pm_domain->ops, state); } else if (dev->type && dev->type->pm) { - pm_dev_dbg(dev, state, "LATE type "); - error = pm_noirq_op(dev, dev->type->pm, state); + info = "LATE type "; + callback = pm_noirq_op(dev->type->pm, state); } else if (dev->class && dev->class->pm) { - pm_dev_dbg(dev, state, "LATE class "); - error = pm_noirq_op(dev, dev->class->pm, state); + info = "LATE class "; + callback = pm_noirq_op(dev->class->pm, state); } else if (dev->bus && dev->bus->pm) { - pm_dev_dbg(dev, state, "LATE "); - error = pm_noirq_op(dev, dev->bus->pm, state); + info = "LATE "; + callback = pm_noirq_op(dev->bus->pm, state); } - return error; + return dpm_run_callback(callback, dev, state, info); } /** @@ -798,6 +785,8 @@ static int legacy_suspend(struct device *dev, pm_message_t state, */ static int __device_suspend(struct device *dev, pm_message_t state, bool async) { + pm_callback_t callback = NULL; + char *info = NULL; int error = 0; dpm_wait_for_children(dev, async); @@ -818,22 +807,22 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async) device_lock(dev); if (dev->pm_domain) { - pm_dev_dbg(dev, state, "power domain "); - error = pm_op(dev, &dev->pm_domain->ops, state); - goto End; + info = "power domain "; + callback = pm_op(&dev->pm_domain->ops, state); + goto Run; } if (dev->type && dev->type->pm) { - pm_dev_dbg(dev, state, "type "); - error = pm_op(dev, dev->type->pm, state); - goto End; + info = "type "; + callback = pm_op(dev->type->pm, state); + goto Run; } if (dev->class) { if (dev->class->pm) { - pm_dev_dbg(dev, state, "class "); - error = pm_op(dev, dev->class->pm, state); - goto End; + info = "class "; + callback = pm_op(dev->class->pm, state); + goto Run; } else if (dev->class->suspend) { pm_dev_dbg(dev, state, "legacy class "); error = legacy_suspend(dev, state, dev->class->suspend); @@ -843,14 +832,18 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async) if (dev->bus) { if (dev->bus->pm) { - pm_dev_dbg(dev, state, ""); - error = pm_op(dev, dev->bus->pm, state); + info = ""; + callback = pm_op(dev->bus->pm, state); } else if (dev->bus->suspend) { pm_dev_dbg(dev, state, "legacy "); error = legacy_suspend(dev, state, dev->bus->suspend); + goto End; } } + Run: + error = dpm_run_callback(callback, dev, state, info); + End: if (!error) { dev->power.is_suspended = true; -- cgit v1.2.3-59-g8ed1b From 35cd133c6130c1eb52806808abee9d62e6854a27 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 18 Dec 2011 00:34:13 +0100 Subject: PM: Run the driver callback directly if the subsystem one is not there Make the PM core execute driver PM callbacks directly if the corresponding subsystem callbacks are not present. There are three reasons for doing that. First, it reflects the behavior of drivers/base/dd.c:really_probe() that runs the driver's .probe() callback directly if the bus type's one is not defined, so this change will remove one arbitrary difference between the PM core and the remaining parts of the driver core. Second, it will allow some subsystems, whose PM callbacks don't do anything except for executing driver callbacks, to be simplified quite a bit by removing those "forward-only" callbacks. Finally, it will allow us to remove one level of indirection in the system suspend and resume code paths where it is not necessary, which is going to lead to less debug noise with initcall_debug passed in the kernel command line (messages won't be printed for driverless devices whose subsystems don't provide PM callbacks among other things). Signed-off-by: Rafael J. Wysocki --- Documentation/power/devices.txt | 37 ++++++----- Documentation/power/runtime_pm.txt | 130 +++++++++++++++++++------------------ drivers/base/power/main.c | 109 ++++++++++++++++++++----------- drivers/base/power/runtime.c | 9 +++ 4 files changed, 170 insertions(+), 115 deletions(-) (limited to 'drivers/base') diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt index 3139fb505dce..20af7def23c8 100644 --- a/Documentation/power/devices.txt +++ b/Documentation/power/devices.txt @@ -126,7 +126,9 @@ The core methods to suspend and resume devices reside in struct dev_pm_ops pointed to by the ops member of struct dev_pm_domain, or by the pm member of struct bus_type, struct device_type and struct class. They are mostly of interest to the people writing infrastructure for platforms and buses, like PCI -or USB, or device type and device class drivers. +or USB, or device type and device class drivers. They also are relevant to the +writers of device drivers whose subsystems (PM domains, device types, device +classes and bus types) don't provide all power management methods. Bus drivers implement these methods as appropriate for the hardware and the drivers using it; PCI works differently from USB, and so on. Not many people @@ -268,32 +270,35 @@ various phases always run after tasks have been frozen and before they are unfrozen. Furthermore, the *_noirq phases run at a time when IRQ handlers have been disabled (except for those marked with the IRQF_NO_SUSPEND flag). -All phases use PM domain, bus, type, or class callbacks (that is, methods -defined in dev->pm_domain->ops, dev->bus->pm, dev->type->pm, or dev->class->pm). -These callbacks are regarded by the PM core as mutually exclusive. Moreover, -PM domain callbacks always take precedence over bus, type and class callbacks, -while type callbacks take precedence over bus and class callbacks, and class -callbacks take precedence over bus callbacks. To be precise, the following -rules are used to determine which callback to execute in the given phase: +All phases use PM domain, bus, type, class or driver callbacks (that is, methods +defined in dev->pm_domain->ops, dev->bus->pm, dev->type->pm, dev->class->pm or +dev->driver->pm). These callbacks are regarded by the PM core as mutually +exclusive. Moreover, PM domain callbacks always take precedence over all of the +other callbacks and, for example, type callbacks take precedence over bus, class +and driver callbacks. To be precise, the following rules are used to determine +which callback to execute in the given phase: - 1. If dev->pm_domain is present, the PM core will attempt to execute the - callback included in dev->pm_domain->ops. If that callback is not - present, no action will be carried out for the given device. + 1. If dev->pm_domain is present, the PM core will choose the callback + included in dev->pm_domain->ops for execution 2. Otherwise, if both dev->type and dev->type->pm are present, the callback - included in dev->type->pm will be executed. + included in dev->type->pm will be chosen for execution. 3. Otherwise, if both dev->class and dev->class->pm are present, the - callback included in dev->class->pm will be executed. + callback included in dev->class->pm will be chosen for execution. 4. Otherwise, if both dev->bus and dev->bus->pm are present, the callback - included in dev->bus->pm will be executed. + included in dev->bus->pm will be chosen for execution. This allows PM domains and device types to override callbacks provided by bus types or device classes if necessary. -These callbacks may in turn invoke device- or driver-specific methods stored in -dev->driver->pm, but they don't have to. +The PM domain, type, class and bus callbacks may in turn invoke device- or +driver-specific methods stored in dev->driver->pm, but they don't have to do +that. + +If the subsystem callback chosen for execution is not present, the PM core will +execute the corresponding method from dev->driver->pm instead if there is one. Entering System Suspend diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index c2ae8bf77d46..4abe83e1045a 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -57,6 +57,10 @@ the following: 4. Bus type of the device, if both dev->bus and dev->bus->pm are present. +If the subsystem chosen by applying the above rules doesn't provide the relevant +callback, the PM core will invoke the corresponding driver callback stored in +dev->driver->pm directly (if present). + The PM core always checks which callback to use in the order given above, so the priority order of callbacks from high to low is: PM domain, device type, class and bus type. Moreover, the high-priority one will always take precedence over @@ -64,86 +68,88 @@ a low-priority one. The PM domain, bus type, device type and class callbacks are referred to as subsystem-level callbacks in what follows. By default, the callbacks are always invoked in process context with interrupts -enabled. However, subsystems can use the pm_runtime_irq_safe() helper function -to tell the PM core that their ->runtime_suspend(), ->runtime_resume() and -->runtime_idle() callbacks may be invoked in atomic context with interrupts -disabled for a given device. This implies that the callback routines in -question must not block or sleep, but it also means that the synchronous helper -functions listed at the end of Section 4 may be used for that device within an -interrupt handler or generally in an atomic context. - -The subsystem-level suspend callback is _entirely_ _responsible_ for handling -the suspend of the device as appropriate, which may, but need not include -executing the device driver's own ->runtime_suspend() callback (from the +enabled. However, the pm_runtime_irq_safe() helper function can be used to tell +the PM core that it is safe to run the ->runtime_suspend(), ->runtime_resume() +and ->runtime_idle() callbacks for the given device in atomic context with +interrupts disabled. This implies that the callback routines in question must +not block or sleep, but it also means that the synchronous helper functions +listed at the end of Section 4 may be used for that device within an interrupt +handler or generally in an atomic context. + +The subsystem-level suspend callback, if present, is _entirely_ _responsible_ +for handling the suspend of the device as appropriate, which may, but need not +include executing the device driver's own ->runtime_suspend() callback (from the PM core's point of view it is not necessary to implement a ->runtime_suspend() callback in a device driver as long as the subsystem-level suspend callback knows what to do to handle the device). - * Once the subsystem-level suspend callback has completed successfully - for given device, the PM core regards the device as suspended, which need - not mean that the device has been put into a low power state. It is - supposed to mean, however, that the device will not process data and will - not communicate with the CPU(s) and RAM until the subsystem-level resume - callback is executed for it. The runtime PM status of a device after - successful execution of the subsystem-level suspend callback is 'suspended'. - - * If the subsystem-level suspend callback returns -EBUSY or -EAGAIN, - the device's runtime PM status is 'active', which means that the device - _must_ be fully operational afterwards. - - * If the subsystem-level suspend callback returns an error code different - from -EBUSY or -EAGAIN, the PM core regards this as a fatal error and will - refuse to run the helper functions described in Section 4 for the device, - until the status of it is directly set either to 'active', or to 'suspended' - (the PM core provides special helper functions for this purpose). - -In particular, if the driver requires remote wake-up capability (i.e. hardware + * Once the subsystem-level suspend callback (or the driver suspend callback, + if invoked directly) has completed successfully for the given device, the PM + core regards the device as suspended, which need not mean that it has been + put into a low power state. It is supposed to mean, however, that the + device will not process data and will not communicate with the CPU(s) and + RAM until the appropriate resume callback is executed for it. The runtime + PM status of a device after successful execution of the suspend callback is + 'suspended'. + + * If the suspend callback returns -EBUSY or -EAGAIN, the device's runtime PM + status remains 'active', which means that the device _must_ be fully + operational afterwards. + + * If the suspend callback returns an error code different from -EBUSY and + -EAGAIN, the PM core regards this as a fatal error and will refuse to run + the helper functions described in Section 4 for the device until its status + is directly set to either'active', or 'suspended' (the PM core provides + special helper functions for this purpose). + +In particular, if the driver requires remote wakeup capability (i.e. hardware mechanism allowing the device to request a change of its power state, such as PCI PME) for proper functioning and device_run_wake() returns 'false' for the device, then ->runtime_suspend() should return -EBUSY. On the other hand, if -device_run_wake() returns 'true' for the device and the device is put into a low -power state during the execution of the subsystem-level suspend callback, it is -expected that remote wake-up will be enabled for the device. Generally, remote -wake-up should be enabled for all input devices put into a low power state at -run time. - -The subsystem-level resume callback is _entirely_ _responsible_ for handling the -resume of the device as appropriate, which may, but need not include executing -the device driver's own ->runtime_resume() callback (from the PM core's point of -view it is not necessary to implement a ->runtime_resume() callback in a device -driver as long as the subsystem-level resume callback knows what to do to handle -the device). - - * Once the subsystem-level resume callback has completed successfully, the PM - core regards the device as fully operational, which means that the device - _must_ be able to complete I/O operations as needed. The runtime PM status - of the device is then 'active'. - - * If the subsystem-level resume callback returns an error code, the PM core - regards this as a fatal error and will refuse to run the helper functions - described in Section 4 for the device, until its status is directly set - either to 'active' or to 'suspended' (the PM core provides special helper - functions for this purpose). - -The subsystem-level idle callback is executed by the PM core whenever the device -appears to be idle, which is indicated to the PM core by two counters, the -device's usage counter and the counter of 'active' children of the device. +device_run_wake() returns 'true' for the device and the device is put into a +low-power state during the execution of the suspend callback, it is expected +that remote wakeup will be enabled for the device. Generally, remote wakeup +should be enabled for all input devices put into low-power states at run time. + +The subsystem-level resume callback, if present, is _entirely_ _responsible_ for +handling the resume of the device as appropriate, which may, but need not +include executing the device driver's own ->runtime_resume() callback (from the +PM core's point of view it is not necessary to implement a ->runtime_resume() +callback in a device driver as long as the subsystem-level resume callback knows +what to do to handle the device). + + * Once the subsystem-level resume callback (or the driver resume callback, if + invoked directly) has completed successfully, the PM core regards the device + as fully operational, which means that the device _must_ be able to complete + I/O operations as needed. The runtime PM status of the device is then + 'active'. + + * If the resume callback returns an error code, the PM core regards this as a + fatal error and will refuse to run the helper functions described in Section + 4 for the device, until its status is directly set to either 'active', or + 'suspended' (by means of special helper functions provided by the PM core + for this purpose). + +The idle callback (a subsystem-level one, if present, or the driver one) is +executed by the PM core whenever the device appears to be idle, which is +indicated to the PM core by two counters, the device's usage counter and the +counter of 'active' children of the device. * If any of these counters is decreased using a helper function provided by the PM core and it turns out to be equal to zero, the other counter is checked. If that counter also is equal to zero, the PM core executes the - subsystem-level idle callback with the device as an argument. + idle callback with the device as its argument. -The action performed by a subsystem-level idle callback is totally dependent on -the subsystem in question, but the expected and recommended action is to check +The action performed by the idle callback is totally dependent on the subsystem +(or driver) in question, but the expected and recommended action is to check if the device can be suspended (i.e. if all of the conditions necessary for suspending the device are satisfied) and to queue up a suspend request for the device in that case. The value returned by this callback is ignored by the PM core. The helper functions provided by the PM core, described in Section 4, guarantee -that the following constraints are met with respect to the bus type's runtime -PM callbacks: +that the following constraints are met with respect to runtime PM callbacks for +one device: (1) The callbacks are mutually exclusive (e.g. it is forbidden to execute ->runtime_suspend() in parallel with ->runtime_resume() or with another diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index b5cef7e7de23..e2cc3d2e0ecc 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -383,10 +383,15 @@ static int device_resume_noirq(struct device *dev, pm_message_t state) info = "EARLY class "; callback = pm_noirq_op(dev->class->pm, state); } else if (dev->bus && dev->bus->pm) { - info = "EARLY "; + info = "EARLY bus "; callback = pm_noirq_op(dev->bus->pm, state); } + if (!callback && dev->driver && dev->driver->pm) { + info = "EARLY driver "; + callback = pm_noirq_op(dev->driver->pm, state); + } + error = dpm_run_callback(callback, dev, state, info); TRACE_RESUME(error); @@ -464,20 +469,20 @@ static int device_resume(struct device *dev, pm_message_t state, bool async) if (dev->pm_domain) { info = "power domain "; callback = pm_op(&dev->pm_domain->ops, state); - goto End; + goto Driver; } if (dev->type && dev->type->pm) { info = "type "; callback = pm_op(dev->type->pm, state); - goto End; + goto Driver; } if (dev->class) { if (dev->class->pm) { info = "class "; callback = pm_op(dev->class->pm, state); - goto End; + goto Driver; } else if (dev->class->resume) { info = "legacy class "; callback = dev->class->resume; @@ -487,14 +492,21 @@ static int device_resume(struct device *dev, pm_message_t state, bool async) if (dev->bus) { if (dev->bus->pm) { - info = ""; + info = "bus "; callback = pm_op(dev->bus->pm, state); } else if (dev->bus->resume) { - info = "legacy "; + info = "legacy bus "; callback = dev->bus->resume; + goto End; } } + Driver: + if (!callback && dev->driver && dev->driver->pm) { + info = "driver "; + callback = pm_op(dev->driver->pm, state); + } + End: error = dpm_run_callback(callback, dev, state, info); dev->power.is_suspended = false; @@ -588,24 +600,33 @@ void dpm_resume(pm_message_t state) */ static void device_complete(struct device *dev, pm_message_t state) { + void (*callback)(struct device *) = NULL; + char *info = NULL; + device_lock(dev); if (dev->pm_domain) { - pm_dev_dbg(dev, state, "completing power domain "); - if (dev->pm_domain->ops.complete) - dev->pm_domain->ops.complete(dev); + info = "completing power domain "; + callback = dev->pm_domain->ops.complete; } else if (dev->type && dev->type->pm) { - pm_dev_dbg(dev, state, "completing type "); - if (dev->type->pm->complete) - dev->type->pm->complete(dev); + info = "completing type "; + callback = dev->type->pm->complete; } else if (dev->class && dev->class->pm) { - pm_dev_dbg(dev, state, "completing class "); - if (dev->class->pm->complete) - dev->class->pm->complete(dev); + info = "completing class "; + callback = dev->class->pm->complete; } else if (dev->bus && dev->bus->pm) { - pm_dev_dbg(dev, state, "completing "); - if (dev->bus->pm->complete) - dev->bus->pm->complete(dev); + info = "completing bus "; + callback = dev->bus->pm->complete; + } + + if (!callback && dev->driver && dev->driver->pm) { + info = "completing driver "; + callback = dev->driver->pm->complete; + } + + if (callback) { + pm_dev_dbg(dev, state, info); + callback(dev); } device_unlock(dev); @@ -704,10 +725,15 @@ static int device_suspend_noirq(struct device *dev, pm_message_t state) info = "LATE class "; callback = pm_noirq_op(dev->class->pm, state); } else if (dev->bus && dev->bus->pm) { - info = "LATE "; + info = "LATE bus "; callback = pm_noirq_op(dev->bus->pm, state); } + if (!callback && dev->driver && dev->driver->pm) { + info = "LATE driver "; + callback = pm_noirq_op(dev->driver->pm, state); + } + return dpm_run_callback(callback, dev, state, info); } @@ -832,16 +858,21 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async) if (dev->bus) { if (dev->bus->pm) { - info = ""; + info = "bus "; callback = pm_op(dev->bus->pm, state); } else if (dev->bus->suspend) { - pm_dev_dbg(dev, state, "legacy "); + pm_dev_dbg(dev, state, "legacy bus "); error = legacy_suspend(dev, state, dev->bus->suspend); goto End; } } Run: + if (!callback && dev->driver && dev->driver->pm) { + info = "driver "; + callback = pm_op(dev->driver->pm, state); + } + error = dpm_run_callback(callback, dev, state, info); End: @@ -949,6 +980,8 @@ int dpm_suspend(pm_message_t state) */ static int device_prepare(struct device *dev, pm_message_t state) { + int (*callback)(struct device *) = NULL; + char *info = NULL; int error = 0; device_lock(dev); @@ -956,25 +989,27 @@ static int device_prepare(struct device *dev, pm_message_t state) dev->power.wakeup_path = device_may_wakeup(dev); if (dev->pm_domain) { - pm_dev_dbg(dev, state, "preparing power domain "); - if (dev->pm_domain->ops.prepare) - error = dev->pm_domain->ops.prepare(dev); - suspend_report_result(dev->pm_domain->ops.prepare, error); + info = "preparing power domain "; + callback = dev->pm_domain->ops.prepare; } else if (dev->type && dev->type->pm) { - pm_dev_dbg(dev, state, "preparing type "); - if (dev->type->pm->prepare) - error = dev->type->pm->prepare(dev); - suspend_report_result(dev->type->pm->prepare, error); + info = "preparing type "; + callback = dev->type->pm->prepare; } else if (dev->class && dev->class->pm) { - pm_dev_dbg(dev, state, "preparing class "); - if (dev->class->pm->prepare) - error = dev->class->pm->prepare(dev); - suspend_report_result(dev->class->pm->prepare, error); + info = "preparing class "; + callback = dev->class->pm->prepare; } else if (dev->bus && dev->bus->pm) { - pm_dev_dbg(dev, state, "preparing "); - if (dev->bus->pm->prepare) - error = dev->bus->pm->prepare(dev); - suspend_report_result(dev->bus->pm->prepare, error); + info = "preparing bus "; + callback = dev->bus->pm->prepare; + } + + if (!callback && dev->driver && dev->driver->pm) { + info = "preparing driver "; + callback = dev->driver->pm->prepare; + } + + if (callback) { + error = callback(dev); + suspend_report_result(callback, error); } device_unlock(dev); diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 8c78443bca8f..c56efd756531 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -250,6 +250,9 @@ static int rpm_idle(struct device *dev, int rpmflags) else callback = NULL; + if (!callback && dev->driver && dev->driver->pm) + callback = dev->driver->pm->runtime_idle; + if (callback) __rpm_callback(callback, dev); @@ -413,6 +416,9 @@ static int rpm_suspend(struct device *dev, int rpmflags) else callback = NULL; + if (!callback && dev->driver && dev->driver->pm) + callback = dev->driver->pm->runtime_suspend; + retval = rpm_callback(callback, dev); if (retval) { __update_runtime_status(dev, RPM_ACTIVE); @@ -633,6 +639,9 @@ static int rpm_resume(struct device *dev, int rpmflags) else callback = NULL; + if (!callback && dev->driver && dev->driver->pm) + callback = dev->driver->pm->runtime_resume; + retval = rpm_callback(callback, dev); if (retval) { __update_runtime_status(dev, RPM_SUSPENDED); -- cgit v1.2.3-59-g8ed1b From 9b39e73d0c2b265a7f8748b0e9a9f09be84079a8 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 18 Dec 2011 00:34:24 +0100 Subject: PM / Sleep: Remove forward-only callbacks from platform bus type The forward-only PM callbacks provided by the platform bus type are not necessary any more, because the PM core executes driver callbacks when the corresponding subsystem callbacks are not present, so drop them. Signed-off-by: Rafael J. Wysocki --- drivers/base/platform.c | 115 ---------------------------------------- include/linux/platform_device.h | 30 +---------- 2 files changed, 1 insertion(+), 144 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 7a24895543e7..7d912d5675d8 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -700,25 +700,6 @@ static int platform_legacy_resume(struct device *dev) return ret; } -int platform_pm_prepare(struct device *dev) -{ - struct device_driver *drv = dev->driver; - int ret = 0; - - if (drv && drv->pm && drv->pm->prepare) - ret = drv->pm->prepare(dev); - - return ret; -} - -void platform_pm_complete(struct device *dev) -{ - struct device_driver *drv = dev->driver; - - if (drv && drv->pm && drv->pm->complete) - drv->pm->complete(dev); -} - #endif /* CONFIG_PM_SLEEP */ #ifdef CONFIG_SUSPEND @@ -741,22 +722,6 @@ int platform_pm_suspend(struct device *dev) return ret; } -int platform_pm_suspend_noirq(struct device *dev) -{ - struct device_driver *drv = dev->driver; - int ret = 0; - - if (!drv) - return 0; - - if (drv->pm) { - if (drv->pm->suspend_noirq) - ret = drv->pm->suspend_noirq(dev); - } - - return ret; -} - int platform_pm_resume(struct device *dev) { struct device_driver *drv = dev->driver; @@ -775,22 +740,6 @@ int platform_pm_resume(struct device *dev) return ret; } -int platform_pm_resume_noirq(struct device *dev) -{ - struct device_driver *drv = dev->driver; - int ret = 0; - - if (!drv) - return 0; - - if (drv->pm) { - if (drv->pm->resume_noirq) - ret = drv->pm->resume_noirq(dev); - } - - return ret; -} - #endif /* CONFIG_SUSPEND */ #ifdef CONFIG_HIBERNATE_CALLBACKS @@ -813,22 +762,6 @@ int platform_pm_freeze(struct device *dev) return ret; } -int platform_pm_freeze_noirq(struct device *dev) -{ - struct device_driver *drv = dev->driver; - int ret = 0; - - if (!drv) - return 0; - - if (drv->pm) { - if (drv->pm->freeze_noirq) - ret = drv->pm->freeze_noirq(dev); - } - - return ret; -} - int platform_pm_thaw(struct device *dev) { struct device_driver *drv = dev->driver; @@ -847,22 +780,6 @@ int platform_pm_thaw(struct device *dev) return ret; } -int platform_pm_thaw_noirq(struct device *dev) -{ - struct device_driver *drv = dev->driver; - int ret = 0; - - if (!drv) - return 0; - - if (drv->pm) { - if (drv->pm->thaw_noirq) - ret = drv->pm->thaw_noirq(dev); - } - - return ret; -} - int platform_pm_poweroff(struct device *dev) { struct device_driver *drv = dev->driver; @@ -881,22 +798,6 @@ int platform_pm_poweroff(struct device *dev) return ret; } -int platform_pm_poweroff_noirq(struct device *dev) -{ - struct device_driver *drv = dev->driver; - int ret = 0; - - if (!drv) - return 0; - - if (drv->pm) { - if (drv->pm->poweroff_noirq) - ret = drv->pm->poweroff_noirq(dev); - } - - return ret; -} - int platform_pm_restore(struct device *dev) { struct device_driver *drv = dev->driver; @@ -915,22 +816,6 @@ int platform_pm_restore(struct device *dev) return ret; } -int platform_pm_restore_noirq(struct device *dev) -{ - struct device_driver *drv = dev->driver; - int ret = 0; - - if (!drv) - return 0; - - if (drv->pm) { - if (drv->pm->restore_noirq) - ret = drv->pm->restore_noirq(dev); - } - - return ret; -} - #endif /* CONFIG_HIBERNATE_CALLBACKS */ static const struct dev_pm_ops platform_dev_pm_ops = { diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 2a23f7d1a825..b5267c951161 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -264,62 +264,34 @@ static inline char *early_platform_driver_setup_func(void) \ } #endif /* MODULE */ -#ifdef CONFIG_PM_SLEEP -extern int platform_pm_prepare(struct device *dev); -extern void platform_pm_complete(struct device *dev); -#else -#define platform_pm_prepare NULL -#define platform_pm_complete NULL -#endif - #ifdef CONFIG_SUSPEND extern int platform_pm_suspend(struct device *dev); -extern int platform_pm_suspend_noirq(struct device *dev); extern int platform_pm_resume(struct device *dev); -extern int platform_pm_resume_noirq(struct device *dev); #else #define platform_pm_suspend NULL #define platform_pm_resume NULL -#define platform_pm_suspend_noirq NULL -#define platform_pm_resume_noirq NULL #endif #ifdef CONFIG_HIBERNATE_CALLBACKS extern int platform_pm_freeze(struct device *dev); -extern int platform_pm_freeze_noirq(struct device *dev); extern int platform_pm_thaw(struct device *dev); -extern int platform_pm_thaw_noirq(struct device *dev); extern int platform_pm_poweroff(struct device *dev); -extern int platform_pm_poweroff_noirq(struct device *dev); extern int platform_pm_restore(struct device *dev); -extern int platform_pm_restore_noirq(struct device *dev); #else #define platform_pm_freeze NULL #define platform_pm_thaw NULL #define platform_pm_poweroff NULL #define platform_pm_restore NULL -#define platform_pm_freeze_noirq NULL -#define platform_pm_thaw_noirq NULL -#define platform_pm_poweroff_noirq NULL -#define platform_pm_restore_noirq NULL #endif #ifdef CONFIG_PM_SLEEP #define USE_PLATFORM_PM_SLEEP_OPS \ - .prepare = platform_pm_prepare, \ - .complete = platform_pm_complete, \ .suspend = platform_pm_suspend, \ .resume = platform_pm_resume, \ .freeze = platform_pm_freeze, \ .thaw = platform_pm_thaw, \ .poweroff = platform_pm_poweroff, \ - .restore = platform_pm_restore, \ - .suspend_noirq = platform_pm_suspend_noirq, \ - .resume_noirq = platform_pm_resume_noirq, \ - .freeze_noirq = platform_pm_freeze_noirq, \ - .thaw_noirq = platform_pm_thaw_noirq, \ - .poweroff_noirq = platform_pm_poweroff_noirq, \ - .restore_noirq = platform_pm_restore_noirq, + .restore = platform_pm_restore, #else #define USE_PLATFORM_PM_SLEEP_OPS #endif -- cgit v1.2.3-59-g8ed1b From 90363ddf0a1a4dccfbb8d0c10b8f488bc7fa69f8 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 18 Dec 2011 00:34:42 +0100 Subject: PM: Drop generic_subsys_pm_ops Since the PM core is now going to execute driver callbacks directly if the corresponding subsystem callbacks are not present, forward-only subsystem callbacks (i.e. such that only execute the corresponding driver callbacks) are not necessary any more. Thus it is possible to remove generic_subsys_pm_ops, because the only callback in there that is not forward-only, .runtime_idle, is not really used by the only user of generic_subsys_pm_ops, which is vio_bus_type. However, the generic callback routines themselves cannot be removed from generic_ops.c, because they are used individually by a number of subsystems. Signed-off-by: Rafael J. Wysocki --- arch/powerpc/kernel/vio.c | 1 - drivers/base/power/generic_ops.c | 25 ------------------------- include/linux/pm.h | 13 ------------- 3 files changed, 39 deletions(-) (limited to 'drivers/base') diff --git a/arch/powerpc/kernel/vio.c b/arch/powerpc/kernel/vio.c index f65af61996bd..8b086299ba25 100644 --- a/arch/powerpc/kernel/vio.c +++ b/arch/powerpc/kernel/vio.c @@ -1406,7 +1406,6 @@ static struct bus_type vio_bus_type = { .match = vio_bus_match, .probe = vio_bus_probe, .remove = vio_bus_remove, - .pm = GENERIC_SUBSYS_PM_OPS, }; /** diff --git a/drivers/base/power/generic_ops.c b/drivers/base/power/generic_ops.c index 5a5b154bc1e9..10bdd793f0bd 100644 --- a/drivers/base/power/generic_ops.c +++ b/drivers/base/power/generic_ops.c @@ -276,28 +276,3 @@ void pm_generic_complete(struct device *dev) pm_runtime_idle(dev); } #endif /* CONFIG_PM_SLEEP */ - -struct dev_pm_ops generic_subsys_pm_ops = { -#ifdef CONFIG_PM_SLEEP - .prepare = pm_generic_prepare, - .suspend = pm_generic_suspend, - .suspend_noirq = pm_generic_suspend_noirq, - .resume = pm_generic_resume, - .resume_noirq = pm_generic_resume_noirq, - .freeze = pm_generic_freeze, - .freeze_noirq = pm_generic_freeze_noirq, - .thaw = pm_generic_thaw, - .thaw_noirq = pm_generic_thaw_noirq, - .poweroff = pm_generic_poweroff, - .poweroff_noirq = pm_generic_poweroff_noirq, - .restore = pm_generic_restore, - .restore_noirq = pm_generic_restore_noirq, - .complete = pm_generic_complete, -#endif -#ifdef CONFIG_PM_RUNTIME - .runtime_suspend = pm_generic_runtime_suspend, - .runtime_resume = pm_generic_runtime_resume, - .runtime_idle = pm_generic_runtime_idle, -#endif -}; -EXPORT_SYMBOL_GPL(generic_subsys_pm_ops); diff --git a/include/linux/pm.h b/include/linux/pm.h index 3f3ed83a9aa5..21e04dd72a84 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -300,19 +300,6 @@ const struct dev_pm_ops name = { \ SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \ } -/* - * Use this for subsystems (bus types, device types, device classes) that don't - * need any special suspend/resume handling in addition to invoking the PM - * callbacks provided by device drivers supporting both the system sleep PM and - * runtime PM, make the pm member point to generic_subsys_pm_ops. - */ -#ifdef CONFIG_PM -extern struct dev_pm_ops generic_subsys_pm_ops; -#define GENERIC_SUBSYS_PM_OPS (&generic_subsys_pm_ops) -#else -#define GENERIC_SUBSYS_PM_OPS NULL -#endif - /** * PM_EVENT_ messages * -- cgit v1.2.3-59-g8ed1b From 40a5f8be2f482783de0f1f0fe856660e489734a8 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 23 Dec 2011 01:23:52 +0100 Subject: PM / QoS: Introduce dev_pm_qos_add_ancestor_request() Some devices, like the I2C controller on SH7372, are not necessary for providing power to their children or forwarding wakeup signals (and generally interrupts) from them. They are only needed by their children when there's some data to transfer, so they may be suspended for the majority of time and resumed on demand, when the children have data to send or receive. For this purpose, however, their power.ignore_children flags have to be set, or the PM core wouldn't allow them to be suspended while their children were active. Unfortunately, in some situations it may take too much time to resume such devices so that they can assist their children in transferring data. For example, if such a device belongs to a PM domain which goes to the "power off" state when that device is suspended, it may take too much time to restore power to the domain in response to the request from one of the device's children. In that case, if the parent's resume time is critical, the domain should stay in the "power on" state, although it still may be desirable to power manage the parent itself (e.g. by manipulating its clock). In general, device PM QoS may be used to address this problem. Namely, if the device's children added PM QoS latency constraints for it, they would be able to prevent it from being put into an overly deep low-power state. However, in some cases the devices needing to be serviced are not the immediate children of a "children-ignoring" device, but its grandchildren or even less direct descendants. In those cases, the entity wanting to add a PM QoS request for a given device's ancestor that ignores its children will have to find it in the first place, so introduce a new helper function that may be used to achieve that. This function, dev_pm_qos_add_ancestor_request(), will search for the first ancestor of the given device whose power.ignore_children flag is set and will add a device PM QoS latency request for that ancestor on behalf of the caller. The request added this way may be removed with the help of dev_pm_qos_remove_request() in the future, like any other device PM QoS latency request. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/qos.c | 25 +++++++++++++++++++++++++ include/linux/pm_qos.h | 5 +++++ 2 files changed, 30 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c index 86de6c50fc41..edf7687615e8 100644 --- a/drivers/base/power/qos.c +++ b/drivers/base/power/qos.c @@ -412,3 +412,28 @@ int dev_pm_qos_remove_global_notifier(struct notifier_block *notifier) return blocking_notifier_chain_unregister(&dev_pm_notifiers, notifier); } EXPORT_SYMBOL_GPL(dev_pm_qos_remove_global_notifier); + +/** + * dev_pm_qos_add_ancestor_request - Add PM QoS request for device's ancestor. + * @dev: Device whose ancestor to add the request for. + * @req: Pointer to the preallocated handle. + * @value: Constraint latency value. + */ +int dev_pm_qos_add_ancestor_request(struct device *dev, + struct dev_pm_qos_request *req, s32 value) +{ + struct device *ancestor = dev->parent; + int error = -ENODEV; + + while (ancestor && !ancestor->power.ignore_children) + ancestor = ancestor->parent; + + if (ancestor) + error = dev_pm_qos_add_request(ancestor, req, value); + + if (error) + req->dev = NULL; + + return error; +} +EXPORT_SYMBOL_GPL(dev_pm_qos_add_ancestor_request); diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h index 83b0ea302a80..fe247b33652d 100644 --- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -91,6 +91,8 @@ int dev_pm_qos_add_global_notifier(struct notifier_block *notifier); int dev_pm_qos_remove_global_notifier(struct notifier_block *notifier); void dev_pm_qos_constraints_init(struct device *dev); void dev_pm_qos_constraints_destroy(struct device *dev); +int dev_pm_qos_add_ancestor_request(struct device *dev, + struct dev_pm_qos_request *req, s32 value); #else static inline int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node, @@ -150,6 +152,9 @@ static inline void dev_pm_qos_constraints_destroy(struct device *dev) { dev->power.power_state = PMSG_INVALID; } +static inline int dev_pm_qos_add_ancestor_request(struct device *dev, + struct dev_pm_qos_request *req, s32 value) + { return 0; } #endif #endif -- cgit v1.2.3-59-g8ed1b