diff options
| -rw-r--r-- | drivers/base/power/domain.c | 161 | ||||
| -rw-r--r-- | include/linux/pm_domain.h | 22 |
2 files changed, 171 insertions, 12 deletions
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 05bb4d4401b2..c2a8821bdb26 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -413,28 +413,47 @@ static int _genpd_power_on(struct generic_pm_domain *genpd, bool timed) unsigned int state_idx = genpd->state_idx; ktime_t time_start; s64 elapsed_ns; - int ret; + int ret, nr_calls = 0; + + /* Notify consumers that we are about to power on. */ + ret = __raw_notifier_call_chain(&genpd->power_notifiers, + GENPD_NOTIFY_PRE_ON, NULL, -1, + &nr_calls); + ret = notifier_to_errno(ret); + if (ret) + goto err; if (!genpd->power_on) - return 0; + goto out; - if (!timed) - return genpd->power_on(genpd); + if (!timed) { + ret = genpd->power_on(genpd); + if (ret) + goto err; + + goto out; + } time_start = ktime_get(); ret = genpd->power_on(genpd); if (ret) - return ret; + goto err; elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start)); if (elapsed_ns <= genpd->states[state_idx].power_on_latency_ns) - return ret; + goto out; genpd->states[state_idx].power_on_latency_ns = elapsed_ns; genpd->max_off_time_changed = true; pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n", genpd->name, "on", elapsed_ns); +out: + raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_ON, NULL); + return 0; +err: + raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_OFF, + NULL); return ret; } @@ -443,29 +462,51 @@ static int _genpd_power_off(struct generic_pm_domain *genpd, bool timed) unsigned int state_idx = genpd->state_idx; ktime_t time_start; s64 elapsed_ns; - int ret; + int ret, nr_calls = 0; + + /* Notify consumers that we are about to power off. */ + ret = __raw_notifier_call_chain(&genpd->power_notifiers, + GENPD_NOTIFY_PRE_OFF, NULL, -1, + &nr_calls); + ret = notifier_to_errno(ret); + if (ret) + goto busy; if (!genpd->power_off) - return 0; + goto out; + + if (!timed) { + ret = genpd->power_off(genpd); + if (ret) + goto busy; - if (!timed) - return genpd->power_off(genpd); + goto out; + } time_start = ktime_get(); ret = genpd->power_off(genpd); if (ret) - return ret; + goto busy; elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start)); if (elapsed_ns <= genpd->states[state_idx].power_off_latency_ns) - return 0; + goto out; genpd->states[state_idx].power_off_latency_ns = elapsed_ns; genpd->max_off_time_changed = true; pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n", genpd->name, "off", elapsed_ns); +out: + raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_OFF, + NULL); return 0; +busy: + if (nr_calls) + __raw_notifier_call_chain(&genpd->power_notifiers, + GENPD_NOTIFY_ON, NULL, nr_calls - 1, + NULL); + return ret; } /** @@ -1592,6 +1633,101 @@ int pm_genpd_remove_device(struct device *dev) } EXPORT_SYMBOL_GPL(pm_genpd_remove_device); +/** + * dev_pm_genpd_add_notifier - Add a genpd power on/off notifier for @dev + * + * @dev: Device that should be associated with the notifier + * @nb: The notifier block to register + * + * Users may call this function to add a genpd power on/off notifier for an + * attached @dev. Only one notifier per device is allowed. The notifier is + * sent when genpd is powering on/off the PM domain. + * + * It is assumed that the user guarantee that the genpd wouldn't be detached + * while this routine is getting called. + * + * Returns 0 on success and negative error values on failures. + */ +int dev_pm_genpd_add_notifier(struct device *dev, struct notifier_block *nb) +{ + struct generic_pm_domain *genpd; + struct generic_pm_domain_data *gpd_data; + int ret; + + genpd = dev_to_genpd_safe(dev); + if (!genpd) + return -ENODEV; + + if (WARN_ON(!dev->power.subsys_data || + !dev->power.subsys_data->domain_data)) + return -EINVAL; + + gpd_data = to_gpd_data(dev->power.subsys_data->domain_data); + if (gpd_data->power_nb) + return -EEXIST; + + genpd_lock(genpd); + ret = raw_notifier_chain_register(&genpd->power_notifiers, nb); + genpd_unlock(genpd); + + if (ret) { + dev_warn(dev, "failed to add notifier for PM domain %s\n", + genpd->name); + return ret; + } + + gpd_data->power_nb = nb; + return 0; +} +EXPORT_SYMBOL_GPL(dev_pm_genpd_add_notifier); + +/** + * dev_pm_genpd_remove_notifier - Remove a genpd power on/off notifier for @dev + * + * @dev: Device that is associated with the notifier + * + * Users may call this function to remove a genpd power on/off notifier for an + * attached @dev. + * + * It is assumed that the user guarantee that the genpd wouldn't be detached + * while this routine is getting called. + * + * Returns 0 on success and negative error values on failures. + */ +int dev_pm_genpd_remove_notifier(struct device *dev) +{ + struct generic_pm_domain *genpd; + struct generic_pm_domain_data *gpd_data; + int ret; + + genpd = dev_to_genpd_safe(dev); + if (!genpd) + return -ENODEV; + + if (WARN_ON(!dev->power.subsys_data || + !dev->power.subsys_data->domain_data)) + return -EINVAL; + + gpd_data = to_gpd_data(dev->power.subsys_data->domain_data); + if (!gpd_data->power_nb) + return -ENODEV; + + genpd_lock(genpd); + ret = raw_notifier_chain_unregister(&genpd->power_notifiers, + gpd_data->power_nb); + genpd_unlock(genpd); + + if (ret) { + dev_warn(dev, "failed to remove notifier for PM domain %s\n", + genpd->name); + return ret; + } + + gpd_data->power_nb = NULL; + return 0; +} +EXPORT_SYMBOL_GPL(dev_pm_genpd_remove_notifier); + static int genpd_add_subdomain(struct generic_pm_domain *genpd, struct generic_pm_domain *subdomain) { @@ -1762,6 +1898,7 @@ int pm_genpd_init(struct generic_pm_domain *genpd, INIT_LIST_HEAD(&genpd->parent_links); INIT_LIST_HEAD(&genpd->child_links); INIT_LIST_HEAD(&genpd->dev_list); + RAW_INIT_NOTIFIER_HEAD(&genpd->power_notifiers); genpd_lock_init(genpd); genpd->gov = gov; INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn); diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index 66f3c5d64d81..db039da0aba2 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -68,6 +68,13 @@ enum gpd_status { GENPD_STATE_OFF, /* PM domain is off */ }; +enum genpd_notication { + GENPD_NOTIFY_PRE_OFF = 0, + GENPD_NOTIFY_OFF, + GENPD_NOTIFY_PRE_ON, + GENPD_NOTIFY_ON, +}; + struct dev_power_governor { bool (*power_down_ok)(struct dev_pm_domain *domain); bool (*suspend_ok)(struct device *dev); @@ -112,6 +119,7 @@ struct generic_pm_domain { cpumask_var_t cpus; /* A cpumask of the attached CPUs */ int (*power_off)(struct generic_pm_domain *domain); int (*power_on)(struct generic_pm_domain *domain); + struct raw_notifier_head power_notifiers; /* Power on/off notifiers */ struct opp_table *opp_table; /* OPP table of the genpd */ unsigned int (*opp_to_performance_state)(struct generic_pm_domain *genpd, struct dev_pm_opp *opp); @@ -178,6 +186,7 @@ struct generic_pm_domain_data { struct pm_domain_data base; struct gpd_timing_data td; struct notifier_block nb; + struct notifier_block *power_nb; int cpu; unsigned int performance_state; void *data; @@ -204,6 +213,8 @@ int pm_genpd_init(struct generic_pm_domain *genpd, struct dev_power_governor *gov, bool is_off); int pm_genpd_remove(struct generic_pm_domain *genpd); int dev_pm_genpd_set_performance_state(struct device *dev, unsigned int state); +int dev_pm_genpd_add_notifier(struct device *dev, struct notifier_block *nb); +int dev_pm_genpd_remove_notifier(struct device *dev); extern struct dev_power_governor simple_qos_governor; extern struct dev_power_governor pm_domain_always_on_gov; @@ -251,6 +262,17 @@ static inline int dev_pm_genpd_set_performance_state(struct device *dev, return -ENOTSUPP; } +static inline int dev_pm_genpd_add_notifier(struct device *dev, + struct notifier_block *nb) +{ + return -ENOTSUPP; +} + +static inline int dev_pm_genpd_remove_notifier(struct device *dev) +{ + return -ENOTSUPP; +} + #define simple_qos_governor (*(struct dev_power_governor *)(NULL)) #define pm_domain_always_on_gov (*(struct dev_power_governor *)(NULL)) #endif |