diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index b1fcbf917974..4925af5c4cf0 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -2171,6 +2171,15 @@ struct generic_pm_domain *of_genpd_remove_last(struct device_node *np) } EXPORT_SYMBOL_GPL(of_genpd_remove_last); +static void genpd_release_dev(struct device *dev) +{ + kfree(dev); +} + +static struct bus_type genpd_bus_type = { + .name = "genpd", +}; + /** * genpd_dev_pm_detach - Detach a device from its PM domain. * @dev: Device to detach. @@ -2208,6 +2217,10 @@ static void genpd_dev_pm_detach(struct device *dev, bool power_off) /* Check if PM domain can be powered off after removing this device. */ genpd_queue_power_off_work(pd); + + /* Unregister the device if it was created by genpd. */ + if (dev->bus == &genpd_bus_type) + device_unregister(dev); } static void genpd_dev_pm_sync(struct device *dev) @@ -2298,6 +2311,67 @@ int genpd_dev_pm_attach(struct device *dev) } EXPORT_SYMBOL_GPL(genpd_dev_pm_attach); +/** + * genpd_dev_pm_attach_by_id - Associate a device with one of its PM domains. + * @dev: The device used to lookup the PM domain. + * @index: The index of the PM domain. + * + * Parse device's OF node to find a PM domain specifier at the provided @index. + * If such is found, creates a virtual device and attaches it to the retrieved + * pm_domain ops. To deal with detaching of the virtual device, the ->detach() + * callback in the struct dev_pm_domain are assigned to genpd_dev_pm_detach(). + * + * Returns the created virtual device if successfully attached PM domain, NULL + * when the device don't need a PM domain, else an ERR_PTR() in case of + * failures. If a power-domain exists for the device, but cannot be found or + * turned on, then ERR_PTR(-EPROBE_DEFER) is returned to ensure that the device + * is not probed and to re-try again later. + */ +struct device *genpd_dev_pm_attach_by_id(struct device *dev, + unsigned int index) +{ + struct device *genpd_dev; + int num_domains; + int ret; + + if (!dev->of_node) + return NULL; + + /* Deal only with devices using multiple PM domains. */ + num_domains = of_count_phandle_with_args(dev->of_node, "power-domains", + "#power-domain-cells"); + if (num_domains < 2 || index >= num_domains) + return NULL; + + /* Allocate and register device on the genpd bus. */ + genpd_dev = kzalloc(sizeof(*genpd_dev), GFP_KERNEL); + if (!genpd_dev) + return ERR_PTR(-ENOMEM); + + dev_set_name(genpd_dev, "genpd:%u:%s", index, dev_name(dev)); + genpd_dev->bus = &genpd_bus_type; + genpd_dev->release = genpd_release_dev; + + ret = device_register(genpd_dev); + if (ret) { + kfree(genpd_dev); + return ERR_PTR(ret); + } + + /* Try to attach the device to the PM domain at the specified index. */ + ret = __genpd_dev_pm_attach(genpd_dev, dev->of_node, index); + if (ret < 1) { + device_unregister(genpd_dev); + return ret ? ERR_PTR(ret) : NULL; + } + + pm_runtime_set_active(genpd_dev); + pm_runtime_enable(genpd_dev); + + return genpd_dev; +} +EXPORT_SYMBOL_GPL(genpd_dev_pm_attach_by_id); + static const struct of_device_id idle_state_match[] = { { .compatible = "domain-idle-state", }, { } @@ -2457,6 +2531,12 @@ unlock: } EXPORT_SYMBOL_GPL(of_genpd_opp_to_performance_state); +static int __init genpd_bus_init(void) +{ + return bus_register(&genpd_bus_type); +} +core_initcall(genpd_bus_init); + #endif /* CONFIG_PM_GENERIC_DOMAINS_OF */ diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index 42e0d649e653..82458e8e2e01 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -237,6 +237,8 @@ unsigned int of_genpd_opp_to_performance_state(struct device *dev, struct device_node *opp_node); int genpd_dev_pm_attach(struct device *dev); +struct device *genpd_dev_pm_attach_by_id(struct device *dev, + unsigned int index); #else /* !CONFIG_PM_GENERIC_DOMAINS_OF */ static inline int of_genpd_add_provider_simple(struct device_node *np, struct generic_pm_domain *genpd) @@ -282,6 +284,12 @@ static inline int genpd_dev_pm_attach(struct device *dev) return 0; } +static inline struct device *genpd_dev_pm_attach_by_id(struct device *dev, + unsigned int index) +{ + return NULL; +} + static inline struct generic_pm_domain *of_genpd_remove_last(struct device_node *np) {