Merge branches 'pm-cpuidle', 'pm-cpufreq', 'pm-domains' and 'pm-sleep'

* pm-cpuidle:
  cpuidle: coupled: remove unused define cpuidle_coupled_lock
  cpuidle: fix fallback mechanism for suspend to idle in absence of enter_freeze

* pm-cpufreq:
  cpufreq: cpufreq-dt: avoid uninitialized variable warnings:
  cpufreq: pxa2xx: fix pxa_cpufreq_change_voltage prototype
  cpufreq: Use list_is_last() to check last entry of the policy list
  cpufreq: Fix NULL reference crash while accessing policy->governor_data

* pm-domains:
  PM / Domains: Fix typo in comment
  PM / Domains: Fix potential deadlock while adding/removing subdomains
  PM / domains: fix lockdep issue for all subdomains

* pm-sleep:
  PM: APM_EMULATION does not depend on PM

drivers/base/power/domain.c

@@ -162,7 +162,7 @@ static int genpd_power_off(struct generic_pm_domain *genpd, bool timed)
 
 /**
  * genpd_queue_power_off_work - Queue up the execution of genpd_poweroff().
- * @genpd: PM domait to power off.
+ * @genpd: PM domain to power off.
  *
  * Queue up the execution of genpd_poweroff() unless it's already been done
  * before.
@@ -172,16 +172,15 @@ static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
 	queue_work(pm_wq, &genpd->power_off_work);
 }
 
-static int genpd_poweron(struct generic_pm_domain *genpd);
-
 /**
  * __genpd_poweron - Restore power to a given PM domain and its masters.
  * @genpd: PM domain to power up.
+ * @depth: nesting count for lockdep.
  *
  * Restore power to @genpd and all of its masters so that it is possible to
  * resume a device belonging to it.
  */
-static int __genpd_poweron(struct generic_pm_domain *genpd)
+static int __genpd_poweron(struct generic_pm_domain *genpd, unsigned int depth)
 {
 	struct gpd_link *link;
 	int ret = 0;
@@ -196,11 +195,16 @@ static int __genpd_poweron(struct generic_pm_domain *genpd)
 	 * with it.
 	 */
 	list_for_each_entry(link, &genpd->slave_links, slave_node) {
-		genpd_sd_counter_inc(link->master);
+		struct generic_pm_domain *master = link->master;
+
+		genpd_sd_counter_inc(master);
+
+		mutex_lock_nested(&master->lock, depth + 1);
+		ret = __genpd_poweron(master, depth + 1);
+		mutex_unlock(&master->lock);
 
-		ret = genpd_poweron(link->master);
 		if (ret) {
-			genpd_sd_counter_dec(link->master);
+			genpd_sd_counter_dec(master);
 			goto err;
 		}
 	}
@@ -232,11 +236,12 @@ static int genpd_poweron(struct generic_pm_domain *genpd)
 	int ret;
 
 	mutex_lock(&genpd->lock);
-	ret = __genpd_poweron(genpd);
+	ret = __genpd_poweron(genpd, 0);
 	mutex_unlock(&genpd->lock);
 	return ret;
 }
 
+
 static int genpd_save_dev(struct generic_pm_domain *genpd, struct device *dev)
 {
 	return GENPD_DEV_CALLBACK(genpd, int, save_state, dev);
@@ -484,7 +489,7 @@ static int pm_genpd_runtime_resume(struct device *dev)
 	}
 
 	mutex_lock(&genpd->lock);
-	ret = __genpd_poweron(genpd);
+	ret = __genpd_poweron(genpd, 0);
 	mutex_unlock(&genpd->lock);
 
 	if (ret)
@@ -1339,8 +1344,8 @@ int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
 	if (!link)
 		return -ENOMEM;
 
-	mutex_lock(&genpd->lock);
-	mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
+	mutex_lock(&subdomain->lock);
+	mutex_lock_nested(&genpd->lock, SINGLE_DEPTH_NESTING);
 
 	if (genpd->status == GPD_STATE_POWER_OFF
 	    &&  subdomain->status != GPD_STATE_POWER_OFF) {
@@ -1363,8 +1368,8 @@ int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
 		genpd_sd_counter_inc(genpd);
 
  out:
-	mutex_unlock(&subdomain->lock);
 	mutex_unlock(&genpd->lock);
+	mutex_unlock(&subdomain->lock);
 	if (ret)
 		kfree(link);
 	return ret;
@@ -1385,7 +1390,8 @@ int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
 	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
 		return -EINVAL;
 
-	mutex_lock(&genpd->lock);
+	mutex_lock(&subdomain->lock);
+	mutex_lock_nested(&genpd->lock, SINGLE_DEPTH_NESTING);
 
 	if (!list_empty(&subdomain->slave_links) || subdomain->device_count) {
 		pr_warn("%s: unable to remove subdomain %s\n", genpd->name,
@@ -1398,22 +1404,19 @@ int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
 		if (link->slave != subdomain)
 			continue;
 
-		mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
-
 		list_del(&link->master_node);
 		list_del(&link->slave_node);
 		kfree(link);
 		if (subdomain->status != GPD_STATE_POWER_OFF)
 			genpd_sd_counter_dec(genpd);
 
-		mutex_unlock(&subdomain->lock);
-
 		ret = 0;
 		break;
 	}
 
 out:
 	mutex_unlock(&genpd->lock);
+	mutex_unlock(&subdomain->lock);
 
 	return ret;
 }

drivers/cpufreq/cpufreq-dt.c

@@ -142,15 +142,16 @@ static int allocate_resources(int cpu, struct device **cdev,
 
 try_again:
 	cpu_reg = regulator_get_optional(cpu_dev, reg);
-	if (IS_ERR(cpu_reg)) {
+	ret = PTR_ERR_OR_ZERO(cpu_reg);
+	if (ret) {
 		/*
 		 * If cpu's regulator supply node is present, but regulator is
 		 * not yet registered, we should try defering probe.
 		 */
-		if (PTR_ERR(cpu_reg) == -EPROBE_DEFER) {
+		if (ret == -EPROBE_DEFER) {
 			dev_dbg(cpu_dev, "cpu%d regulator not ready, retry\n",
 				cpu);
-			return -EPROBE_DEFER;
+			return ret;
 		}
 
 		/* Try with "cpu-supply" */
@@ -159,18 +160,16 @@ static int allocate_resources(int cpu, struct device **cdev,
 			goto try_again;
 		}
 
-		dev_dbg(cpu_dev, "no regulator for cpu%d: %ld\n",
-			cpu, PTR_ERR(cpu_reg));
+		dev_dbg(cpu_dev, "no regulator for cpu%d: %d\n", cpu, ret);
 	}
 
 	cpu_clk = clk_get(cpu_dev, NULL);
-	if (IS_ERR(cpu_clk)) {
+	ret = PTR_ERR_OR_ZERO(cpu_clk);
+	if (ret) {
 		/* put regulator */
 		if (!IS_ERR(cpu_reg))
 			regulator_put(cpu_reg);
 
-		ret = PTR_ERR(cpu_clk);
-
 		/*
 		 * If cpu's clk node is present, but clock is not yet
 		 * registered, we should try defering probe.

drivers/cpufreq/cpufreq.c

@@ -48,11 +48,11 @@ static struct cpufreq_policy *next_policy(struct cpufreq_policy *policy,
 					  bool active)
 {
 	do {
-		policy = list_next_entry(policy, policy_list);
-
 		/* No more policies in the list */
-		if (&policy->policy_list == &cpufreq_policy_list)
+		if (list_is_last(&policy->policy_list, &cpufreq_policy_list))
 			return NULL;
+
+		policy = list_next_entry(policy, policy_list);
 	} while (!suitable_policy(policy, active));
 
 	return policy;

drivers/cpufreq/cpufreq_governor.c

@@ -387,16 +387,18 @@ static int cpufreq_governor_init(struct cpufreq_policy *policy,
 	if (!have_governor_per_policy())
 		cdata->gdbs_data = dbs_data;
 
+	policy->governor_data = dbs_data;
+
 	ret = sysfs_create_group(get_governor_parent_kobj(policy),
 				 get_sysfs_attr(dbs_data));
 	if (ret)
 		goto reset_gdbs_data;
 
-	policy->governor_data = dbs_data;
-
 	return 0;
 
 reset_gdbs_data:
+	policy->governor_data = NULL;
+
 	if (!have_governor_per_policy())
 		cdata->gdbs_data = NULL;
 	cdata->exit(dbs_data, !policy->governor->initialized);
@@ -417,16 +419,19 @@ static int cpufreq_governor_exit(struct cpufreq_policy *policy,
 	if (!cdbs->shared || cdbs->shared->policy)
 		return -EBUSY;
 
-	policy->governor_data = NULL;
 	if (!--dbs_data->usage_count) {
 		sysfs_remove_group(get_governor_parent_kobj(policy),
 				   get_sysfs_attr(dbs_data));
 
+		policy->governor_data = NULL;
+
 		if (!have_governor_per_policy())
 			cdata->gdbs_data = NULL;
 
 		cdata->exit(dbs_data, policy->governor->initialized == 1);
 		kfree(dbs_data);
+	} else {
+		policy->governor_data = NULL;
 	}
 
 	free_common_dbs_info(policy, cdata);

drivers/cpufreq/pxa2xx-cpufreq.c

@@ -202,7 +202,7 @@ static void __init pxa_cpufreq_init_voltages(void)
 	}
 }
 #else
-static int pxa_cpufreq_change_voltage(struct pxa_freqs *pxa_freq)
+static int pxa_cpufreq_change_voltage(const struct pxa_freqs *pxa_freq)
 {
 	return 0;
 }

drivers/cpuidle/coupled.c

@@ -119,7 +119,6 @@ struct cpuidle_coupled {
 
 #define CPUIDLE_COUPLED_NOT_IDLE	(-1)
 
-static DEFINE_MUTEX(cpuidle_coupled_lock);
 static DEFINE_PER_CPU(struct call_single_data, cpuidle_coupled_poke_cb);
 
 /*

drivers/cpuidle/cpuidle.c

@@ -153,7 +153,7 @@ int cpuidle_enter_freeze(struct cpuidle_driver *drv, struct cpuidle_device *dev)
 	 * be frozen safely.
 	 */
 	index = find_deepest_state(drv, dev, UINT_MAX, 0, true);
-	if (index >= 0)
+	if (index > 0)
 		enter_freeze_proper(drv, dev, index);
 
 	return index;

kernel/power/Kconfig

@@ -235,7 +235,7 @@ config PM_TRACE_RTC
 
 config APM_EMULATION
 	tristate "Advanced Power Management Emulation"
-	depends on PM && SYS_SUPPORTS_APM_EMULATION
+	depends on SYS_SUPPORTS_APM_EMULATION
 	help
 	  APM is a BIOS specification for saving power using several different
 	  techniques. This is mostly useful for battery powered laptops with

kernel/sched/idle.c

@@ -162,7 +162,7 @@ static void cpuidle_idle_call(void)
 	 */
 	if (idle_should_freeze()) {
 		entered_state = cpuidle_enter_freeze(drv, dev);
-		if (entered_state >= 0) {
+		if (entered_state > 0) {
 			local_irq_enable();
 			goto exit_idle;
 		}