In a step to move away from using genpd's name based APIs, such as the pm_genpd_add_subdomain_names(), provide an API to lookup an already initialized generic PM domain by its device node. This API would typically be a called from SOC specific code, to fetch a handle to the domain. Especially convenient to configure subdomains and when the hierarchy of the domains are described in DT. Do note, before pm_genpd_init() is invoked to initialize a generic PM domain, it's the callers responsibility to assign the new ->dev_node pointer in the struct generic_pm_domain, to enable pm_genpd_lookup() to find the domain. Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> --- The background to why I propose this patch comes from a discussion around the below patchset: https://lkml.org/lkml/2014/11/24/290 --- drivers/base/power/domain.c | 26 ++++++++++++++++++++++++++ include/linux/pm_domain.h | 2 ++ 2 files changed, 28 insertions(+) diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 735c473..34555eb 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -75,6 +75,32 @@ struct generic_pm_domain *dev_to_genpd(struct device *dev) return pd_to_genpd(dev->pm_domain); } +/** + * pm_genpd_lookup - Fetch a generic PM domain object by device node + * @node: Device node to a corresponding genpd. + * + * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR() + * on failure. + */ +struct generic_pm_domain *pm_genpd_lookup(struct device_node *node) +{ + struct generic_pm_domain *genpd = ERR_PTR(-ENOENT), *gpd; + + if (IS_ERR_OR_NULL(node)) + return ERR_PTR(-EINVAL); + + mutex_lock(&gpd_list_lock); + list_for_each_entry(gpd, &gpd_list, gpd_list_node) { + if (gpd->dev_node == node) { + genpd = gpd; + break; + } + } + mutex_unlock(&gpd_list_lock); + return genpd; +} +EXPORT_SYMBOL_GPL(pm_genpd_lookup); + static int genpd_stop_dev(struct generic_pm_domain *genpd, struct device *dev) { return GENPD_DEV_TIMED_CALLBACK(genpd, int, stop, dev, diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index 8cbd32e..322cb7c 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -53,6 +53,7 @@ struct generic_pm_domain { struct dev_power_governor *gov; struct work_struct power_off_work; const char *name; + struct device_node *dev_node; /* Device node for the PM domain */ 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 */ @@ -126,6 +127,7 @@ static inline struct generic_pm_domain_data *dev_gpd_data(struct device *dev) } extern struct generic_pm_domain *dev_to_genpd(struct device *dev); +extern struct generic_pm_domain *pm_genpd_lookup(struct device_node *node); extern int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev, struct gpd_timing_data *td); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
 |