The genpd framework allows users to add PM domains via the pm_genpd_init()
function, however, there is no corresponding function to remove a PM
domain. For most devices this may be fine as the PM domains are never
removed, however, for devices that wish to populate the PM domains from
within a driver, having the ability to remove a PM domain if the probing
of the device fails or the driver is unloaded is necessary.
Add the function pm_genpd_remove() to remove a PM domain by referencing
it's generic_pm_domain structure.
PM domains can only be removed if they are not a parent domain to
another PM domain and have no devices associated with them.
Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx>
---
drivers/base/power/domain.c | 46 +++++++++++++++++++++++++++++++++++++++++++++
include/linux/pm_domain.h | 5 +++++
2 files changed, 51 insertions(+)
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 7ce4608bbbe0..72b973539205 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -1356,6 +1356,52 @@ int pm_genpd_init(struct generic_pm_domain *genpd,
}
EXPORT_SYMBOL_GPL(pm_genpd_init);
+/**
+ * pm_genpd_remove - Remove a generic I/O PM domain
+ * @genpd: Pointer to PM domain that is to be removed.
+ *
+ * To remove the PM domain, this function:
+ * - Removes the PM domain as a subdomain to any parent domains,
+ * if it was added.
+ * - Removes the PM domain from the list of registered PM domains.
+ *
+ * The PM domain will only be removed, if it is not a parent to any
+ * other PM domain and has no devices associated with it.
+ */
+int pm_genpd_remove(struct generic_pm_domain *genpd)
+{
+ struct gpd_link *l, *link;
+ int ret = 0;
+
+ if (IS_ERR_OR_NULL(genpd))
+ return -EINVAL;
+
+ mutex_lock(&gpd_list_lock);
+ mutex_lock(&genpd->lock);
+
+ if (!list_empty(&genpd->master_links) || genpd->device_count) {
+ mutex_unlock(&genpd->lock);
+ mutex_unlock(&gpd_list_lock);
+ pr_err("%s: unable to remove %s\n", __func__, genpd->name);
+ return -EBUSY;
+ }
+
+ list_for_each_entry_safe(link, l, &genpd->slave_links, slave_node) {
+ list_del(&link->master_node);
+ list_del(&link->slave_node);
+ kfree(link);
+ }
+
+ list_del(&genpd->gpd_list_node);
+ mutex_unlock(&genpd->lock);
+ cancel_work_sync(&genpd->power_off_work);
+ mutex_unlock(&gpd_list_lock);
+ pr_debug("%s: removed %s\n", __func__, genpd->name);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pm_genpd_remove);
+
#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
typedef struct generic_pm_domain *(*genpd_xlate_t)(struct of_phandle_args *args,
diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index f103869db443..fbdc5c4588ef 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h
@@ -128,6 +128,7 @@ extern int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
struct generic_pm_domain *target);
extern int pm_genpd_init(struct generic_pm_domain *genpd,
struct dev_power_governor *gov, bool is_off);
+extern int pm_genpd_remove(struct generic_pm_domain *genpd);
extern struct dev_power_governor simple_qos_governor;
extern struct dev_power_governor pm_domain_always_on_gov;
@@ -163,6 +164,10 @@ static inline int pm_genpd_init(struct generic_pm_domain *genpd,
{
return -ENOSYS;
}
+static inline int pm_genpd_remove(struct generic_pm_domain *genpd)
+{
+ return -ENOTSUPP;
+}
#endif
static inline int pm_genpd_add_device(struct generic_pm_domain *genpd,
--
2.1.4
--
To unsubscribe from this list: send the line "unsubscribe linux-tegra" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
