diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 37ab7f1ef178..9af75ba0472a 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -1916,6 +1916,100 @@ out: return ret ? -EPROBE_DEFER : 0; } EXPORT_SYMBOL_GPL(genpd_dev_pm_attach); + +static const struct of_device_id idle_state_match[] = { + { .compatible = "arm,idle-state", }, + { } +}; + +static int genpd_parse_state(struct genpd_power_state *genpd_state, + struct device_node *state_node) +{ + int err; + u32 residency; + u32 entry_latency, exit_latency; + const struct of_device_id *match_id; + + match_id = of_match_node(idle_state_match, state_node); + if (!match_id) + return -EINVAL; + + err = of_property_read_u32(state_node, "entry-latency-us", + &entry_latency); + if (err) { + pr_debug(" * %s missing entry-latency-us property\n", + state_node->full_name); + return -EINVAL; + } + + err = of_property_read_u32(state_node, "exit-latency-us", + &exit_latency); + if (err) { + pr_debug(" * %s missing exit-latency-us property\n", + state_node->full_name); + return -EINVAL; + } + + err = of_property_read_u32(state_node, "min-residency-us", &residency); + if (!err) + genpd_state->residency_ns = 1000 * residency; + + genpd_state->power_on_latency_ns = 1000 * exit_latency; + genpd_state->power_off_latency_ns = 1000 * entry_latency; + + return 0; +} + +/** + * of_genpd_parse_idle_states: Return array of idle states for the genpd. + * + * @dn: The genpd device node + * @states: The pointer to which the state array will be saved. + * @n: The count of elements in the array returned from this function. + * + * Returns the device states parsed from the OF node. The memory for the states + * is allocated by this function and is the responsibility of the caller to + * free the memory after use. + */ +int of_genpd_parse_idle_states(struct device_node *dn, + struct genpd_power_state **states, int *n) +{ + struct genpd_power_state *st; + struct device_node *np; + int i = 0; + int err, ret; + int count; + struct of_phandle_iterator it; + + count = of_count_phandle_with_args(dn, "domain-idle-states", NULL); + if (!count) + return -EINVAL; + + st = kcalloc(count, sizeof(*st), GFP_KERNEL); + if (!st) + return -ENOMEM; + + /* Loop over the phandles until all the requested entry is found */ + of_for_each_phandle(&it, err, dn, "domain-idle-states", NULL, 0) { + np = it.node; + ret = genpd_parse_state(&st[i++], np); + if (ret) { + pr_err + ("Parsing idle state node %s failed with err %d\n", + np->full_name, ret); + of_node_put(np); + kfree(st); + return ret; + } + } + + *n = count; + *states = st; + + return 0; +} +EXPORT_SYMBOL_GPL(of_genpd_parse_idle_states); + #endif /* CONFIG_PM_GENERIC_DOMAINS_OF */ diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index f4492eb71701..b4894969fbec 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -205,6 +205,8 @@ extern int of_genpd_add_device(struct of_phandle_args *args, extern int of_genpd_add_subdomain(struct of_phandle_args *parent, struct of_phandle_args *new_subdomain); extern struct generic_pm_domain *of_genpd_remove_last(struct device_node *np); +extern int of_genpd_parse_idle_states(struct device_node *dn, + struct genpd_power_state **states, int *n); int genpd_dev_pm_attach(struct device *dev); #else /* !CONFIG_PM_GENERIC_DOMAINS_OF */ @@ -234,6 +236,12 @@ static inline int of_genpd_add_subdomain(struct of_phandle_args *parent, return -ENODEV; } +static inline int of_genpd_parse_idle_states(struct device_node *dn, + struct genpd_power_state **states, int *n) +{ + return -ENODEV; +} + static inline int genpd_dev_pm_attach(struct device *dev) { return -ENODEV;