| Message ID | 1417097653-22599-1-git-send-email-ulf.hansson@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thursday, November 27, 2014 03:14:13 PM Ulf Hansson wrote: > 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@linaro.org> > --- > > 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 */ Please don't add DT-specific members to generic data structures. You can use struct fwnode_handle (currently in linux-next) instead. > 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); >
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);
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@linaro.org> --- 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(+)