Merge tag 'pm+acpi-3.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI material from Rafael J Wysocki:
 "These are fixes (operating performance points library, cpufreq-dt
  driver, cpufreq core, ACPI backlight, cpupower tool), cleanups
  (cpuidle), new processor IDs for the RAPL (Running Average Power
  Limit) power capping driver, and a modification of the generic power
  domains framework allowing modular drivers to call one of its helper
  functions.

  Specifics:

   - Fix for a potential NULL pointer dereference in the cpufreq core
     due to an initialization race condition (Ethan Zhao).

   - Fixes for abuse of the OPP (Operating Performance Points) API
     related to RCU and other minor issues in the OPP library and the
     cpufreq-dt driver (Dmitry Torokhov).

   - cpuidle governors cleanup making them measure idle duration in a
     better way without using the CPUIDLE_FLAG_TIME_INVALID flag which
     allows that flag to be dropped from the ACPI cpuidle driver and
     from the core too (Len Brown).

   - New ACPI backlight blacklist entries for Samsung machines without a
     working native backlight interface that need to use the ACPI
     backlight instead (Aaron Lu).

   - New CPU IDs of future Intel Xeon CPUs for the Intel RAPL power
     capping driver (Jacob Pan).

   - Generic power domains framework modification to export the
     of_genpd_get_from_provider() function to modular drivers that will
     allow future driver modifications to be based on the mainline (Amit
     Daniel Kachhap).

   - Two fixes for the cpupower tool (Michal Privoznik, Prarit
     Bhargava)"

* tag 'pm+acpi-3.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / video: Add some Samsung models to disable_native_backlight list
  tools / cpupower: Fix no idle state information return value
  tools / cpupower: Correctly detect if running as root
  cpufreq: fix a NULL pointer dereference in __cpufreq_governor()
  cpufreq-dt: defer probing if OPP table is not ready
  PM / OPP: take RCU lock in dev_pm_opp_get_opp_count
  PM / OPP: fix warning in of_free_opp_table()
  PM / OPP: add some lockdep annotations
  powercap / RAPL: add IDs for future Xeon CPUs
  PM / Domains: Export of_genpd_get_from_provider function
  cpuidle / ACPI: remove unused CPUIDLE_FLAG_TIME_INVALID
  cpuidle: ladder: Better idle duration measurement without using CPUIDLE_FLAG_TIME_INVALID
  cpuidle: menu: Better idle duration measurement without using CPUIDLE_FLAG_TIME_INVALID

13 files changed, 89 insertions, 37 deletions

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 499536504698..87b704e41877 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -985,8 +985,6 @@ static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr)
                 state->flags = 0;
                 switch (cx->type) {
                         case ACPI_STATE_C1:
-                        if (cx->entry_method != ACPI_CSTATE_FFH)
-                                state->flags |= CPUIDLE_FLAG_TIME_INVALID;
 
                         state->enter = acpi_idle_enter_c1;
                         state->enter_dead = acpi_idle_play_dead;
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 1eaadff2e198..c72e79d2c5ad 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -505,6 +505,23 @@ static struct dmi_system_id video_dmi_table[] __initdata = {
                 DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY 15 Notebook PC"),
                 },
         },
+
+        {
+         .callback = video_disable_native_backlight,
+         .ident = "SAMSUNG 870Z5E/880Z5E/680Z5E",
+         .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
+                DMI_MATCH(DMI_PRODUCT_NAME, "870Z5E/880Z5E/680Z5E"),
+                },
+        },
+        {
+         .callback = video_disable_native_backlight,
+         .ident = "SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V",
+         .matches = {
+                DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
+                DMI_MATCH(DMI_PRODUCT_NAME, "370R4E/370R4V/370R5E/3570RE/370R5V"),
+                },
+        },
         {}
 };
 
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 6a103a35ea9b..0d8780c04a5e 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -2088,7 +2088,7 @@ EXPORT_SYMBOL_GPL(of_genpd_del_provider);
  * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR()
  * on failure.
  */
-static struct generic_pm_domain *of_genpd_get_from_provider(
+struct generic_pm_domain *of_genpd_get_from_provider(
                                         struct of_phandle_args *genpdspec)
 {
         struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
@@ -2108,6 +2108,7 @@ static struct generic_pm_domain *of_genpd_get_from_provider(
 
         return genpd;
 }
+EXPORT_SYMBOL_GPL(of_genpd_get_from_provider);
 
 /**
  * genpd_dev_pm_detach - Detach a device from its PM domain.
diff --git a/drivers/base/power/opp.c b/drivers/base/power/opp.c
index d24dd614a0bd..106c69359306 100644
--- a/drivers/base/power/opp.c
+++ b/drivers/base/power/opp.c
@@ -108,6 +108,14 @@ static LIST_HEAD(dev_opp_list);
 /* Lock to allow exclusive modification to the device and opp lists */
 static DEFINE_MUTEX(dev_opp_list_lock);
 
+#define opp_rcu_lockdep_assert()                                        \
+do {                                                                    \
+        rcu_lockdep_assert(rcu_read_lock_held() ||                      \
+                                lockdep_is_held(&dev_opp_list_lock),    \
+                           "Missing rcu_read_lock() or "                \
+                           "dev_opp_list_lock protection");             \
+} while (0)
+
 /**
  * find_device_opp() - find device_opp struct using device pointer
  * @dev:        device pointer used to lookup device OPPs
@@ -208,9 +216,7 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_get_freq);
  * This function returns the number of available opps if there are any,
  * else returns 0 if none or the corresponding error value.
  *
- * Locking: This function must be called under rcu_read_lock(). This function
- * internally references two RCU protected structures: device_opp and opp which
- * are safe as long as we are under a common RCU locked section.
+ * Locking: This function takes rcu_read_lock().
  */
 int dev_pm_opp_get_opp_count(struct device *dev)
 {
@@ -218,11 +224,14 @@ int dev_pm_opp_get_opp_count(struct device *dev)
         struct dev_pm_opp *temp_opp;
         int count = 0;
 
+        rcu_read_lock();
+
         dev_opp = find_device_opp(dev);
         if (IS_ERR(dev_opp)) {
-                int r = PTR_ERR(dev_opp);
-                dev_err(dev, "%s: device OPP not found (%d)\n", __func__, r);
-                return r;
+                count = PTR_ERR(dev_opp);
+                dev_err(dev, "%s: device OPP not found (%d)\n",
+                        __func__, count);
+                goto out_unlock;
         }
 
         list_for_each_entry_rcu(temp_opp, &dev_opp->opp_list, node) {
@@ -230,6 +239,8 @@ int dev_pm_opp_get_opp_count(struct device *dev)
                         count++;
         }
 
+out_unlock:
+        rcu_read_unlock();
         return count;
 }
 EXPORT_SYMBOL_GPL(dev_pm_opp_get_opp_count);
@@ -267,6 +278,8 @@ struct dev_pm_opp *dev_pm_opp_find_freq_exact(struct device *dev,
         struct device_opp *dev_opp;
         struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);
 
+        opp_rcu_lockdep_assert();
+
         dev_opp = find_device_opp(dev);
         if (IS_ERR(dev_opp)) {
                 int r = PTR_ERR(dev_opp);
@@ -313,6 +326,8 @@ struct dev_pm_opp *dev_pm_opp_find_freq_ceil(struct device *dev,
         struct device_opp *dev_opp;
         struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);
 
+        opp_rcu_lockdep_assert();
+
         if (!dev || !freq) {
                 dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq);
                 return ERR_PTR(-EINVAL);
@@ -361,6 +376,8 @@ struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev,
         struct device_opp *dev_opp;
         struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);
 
+        opp_rcu_lockdep_assert();
+
         if (!dev || !freq) {
                 dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq);
                 return ERR_PTR(-EINVAL);
@@ -783,9 +800,15 @@ void of_free_opp_table(struct device *dev)
 
         /* Check for existing list for 'dev' */
         dev_opp = find_device_opp(dev);
-        if (WARN(IS_ERR(dev_opp), "%s: dev_opp: %ld\n", dev_name(dev),
-                 PTR_ERR(dev_opp)))
+        if (IS_ERR(dev_opp)) {
+                int error = PTR_ERR(dev_opp);
+                if (error != -ENODEV)
+                        WARN(1, "%s: dev_opp: %d\n",
+                             IS_ERR_OR_NULL(dev) ?
+                                        "Invalid device" : dev_name(dev),
+                             error);
                 return;
+        }
 
         /* Hold our list modification lock here */
         mutex_lock(&dev_opp_list_lock);
diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c
index f56147a1daed..fde97d6e31d6 100644
--- a/drivers/cpufreq/cpufreq-dt.c
+++ b/drivers/cpufreq/cpufreq-dt.c
@@ -211,6 +211,17 @@ static int cpufreq_init(struct cpufreq_policy *policy)
         /* OPPs might be populated at runtime, don't check for error here */
         of_init_opp_table(cpu_dev);
 
+        /*
+         * But we need OPP table to function so if it is not there let's
+         * give platform code chance to provide it for us.
+         */
+        ret = dev_pm_opp_get_opp_count(cpu_dev);
+        if (ret <= 0) {
+                pr_debug("OPP table is not ready, deferring probe\n");
+                ret = -EPROBE_DEFER;
+                goto out_free_opp;
+        }
+
         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
         if (!priv) {
                 ret = -ENOMEM;
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index a09a29c312a9..46bed4f81cde 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -2028,6 +2028,12 @@ static int __cpufreq_governor(struct cpufreq_policy *policy,
         /* Don't start any governor operations if we are entering suspend */
         if (cpufreq_suspended)
                 return 0;
+        /*
+         * Governor might not be initiated here if ACPI _PPC changed
+         * notification happened, so check it.
+         */
+        if (!policy->governor)
+                return -EINVAL;
 
         if (policy->governor->max_transition_latency &&
             policy->cpuinfo.transition_latency >
diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c
index 37263d9a1051..401c0106ed34 100644
--- a/drivers/cpuidle/governors/ladder.c
+++ b/drivers/cpuidle/governors/ladder.c
@@ -79,12 +79,7 @@ static int ladder_select_state(struct cpuidle_driver *drv,
 
         last_state = &ldev->states[last_idx];
 
-        if (!(drv->states[last_idx].flags & CPUIDLE_FLAG_TIME_INVALID)) {
-                last_residency = cpuidle_get_last_residency(dev) - \
-                                         drv->states[last_idx].exit_latency;
-        }
-        else
-                last_residency = last_state->threshold.promotion_time + 1;
+        last_residency = cpuidle_get_last_residency(dev) - drv->states[last_idx].exit_latency;
 
         /* consider promotion */
         if (last_idx < drv->state_count - 1 &&
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index 659d7b0c9ebf..40580794e23d 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -396,8 +396,8 @@ static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev)
          * power state and occurrence of the wakeup event.
          *
          * If the entered idle state didn't support residency measurements,
-         * we are basically lost in the dark how much time passed.
-         * As a compromise, assume we slept for the whole expected time.
+         * we use them anyway if they are short, and if long,
+         * truncate to the whole expected time.
          *
          * Any measured amount of time will include the exit latency.
          * Since we are interested in when the wakeup begun, not when it
@@ -405,22 +405,17 @@ static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev)
          * the measured amount of time is less than the exit latency,
          * assume the state was never reached and the exit latency is 0.
          */
-        if (unlikely(target->flags & CPUIDLE_FLAG_TIME_INVALID)) {
-                /* Use timer value as is */
-                measured_us = data->next_timer_us;
 
-        } else {
-                /* Use measured value */
-                measured_us = cpuidle_get_last_residency(dev);
+        /* measured value */
+        measured_us = cpuidle_get_last_residency(dev);
 
-                /* Deduct exit latency */
-                if (measured_us > target->exit_latency)
-                        measured_us -= target->exit_latency;
+        /* Deduct exit latency */
+        if (measured_us > target->exit_latency)
+                measured_us -= target->exit_latency;
 
-                /* Make sure our coefficients do not exceed unity */
-                if (measured_us > data->next_timer_us)
-                        measured_us = data->next_timer_us;
-        }
+        /* Make sure our coefficients do not exceed unity */
+        if (measured_us > data->next_timer_us)
+                measured_us = data->next_timer_us;
 
         /* Update our correction ratio */
         new_factor = data->correction_factor[data->bucket];
diff --git a/drivers/powercap/intel_rapl.c b/drivers/powercap/intel_rapl.c
index c71443c4f265..97b5e4ee1ca4 100644
--- a/drivers/powercap/intel_rapl.c
+++ b/drivers/powercap/intel_rapl.c
@@ -1041,6 +1041,7 @@ static const struct x86_cpu_id rapl_ids[] = {
         RAPL_CPU(0x45, rapl_defaults_core),/* Haswell ULT */
         RAPL_CPU(0x4C, rapl_defaults_atom),/* Braswell */
         RAPL_CPU(0x4A, rapl_defaults_atom),/* Tangier */
+        RAPL_CPU(0x56, rapl_defaults_core),/* Future Xeon */
         RAPL_CPU(0x5A, rapl_defaults_atom),/* Annidale */
         {}
 };
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index a07e087f54b2..ab70f3bc44ad 100644
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -53,7 +53,6 @@ struct cpuidle_state {
 };
 
 /* Idle State Flags */
-#define CPUIDLE_FLAG_TIME_INVALID       (0x01) /* is residency time measurable? */
 #define CPUIDLE_FLAG_COUPLED    (0x02) /* state applies to multiple cpus */
 #define CPUIDLE_FLAG_TIMER_STOP (0x04)  /* timer is stopped on this state */
 
@@ -89,8 +88,6 @@ DECLARE_PER_CPU(struct cpuidle_device, cpuidle_dev);
 /**
  * cpuidle_get_last_residency - retrieves the last state's residency time
  * @dev: the target CPU
- *
- * NOTE: this value is invalid if CPUIDLE_FLAG_TIME_INVALID is set
  */
 static inline int cpuidle_get_last_residency(struct cpuidle_device *dev)
 {
diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index 6cd20d5e651b..a9edab2c787a 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h
@@ -271,6 +271,8 @@ typedef struct generic_pm_domain *(*genpd_xlate_t)(struct of_phandle_args *args,
 int __of_genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
                         void *data);
 void of_genpd_del_provider(struct device_node *np);
+struct generic_pm_domain *of_genpd_get_from_provider(
+                        struct of_phandle_args *genpdspec);
 
 struct generic_pm_domain *__of_genpd_xlate_simple(
                                         struct of_phandle_args *genpdspec,
@@ -288,6 +290,12 @@ static inline int __of_genpd_add_provider(struct device_node *np,
 }
 static inline void of_genpd_del_provider(struct device_node *np) {}
 
+static inline struct generic_pm_domain *of_genpd_get_from_provider(
+                        struct of_phandle_args *genpdspec)
+{
+        return NULL;
+}
+
 #define __of_genpd_xlate_simple         NULL
 #define __of_genpd_xlate_onecell        NULL
 
diff --git a/tools/power/cpupower/utils/cpupower.c b/tools/power/cpupower/utils/cpupower.c
index 7cdcf88659c7..9ea914378985 100644
--- a/tools/power/cpupower/utils/cpupower.c
+++ b/tools/power/cpupower/utils/cpupower.c
@@ -199,7 +199,7 @@ int main(int argc, const char *argv[])
         }
 
         get_cpu_info(0, &cpupower_cpu_info);
-        run_as_root = !getuid();
+        run_as_root = !geteuid();
         if (run_as_root) {
                 ret = uname(&uts);
                 if (!ret && !strcmp(uts.machine, "x86_64") &&
diff --git a/tools/power/cpupower/utils/helpers/sysfs.c b/tools/power/cpupower/utils/helpers/sysfs.c
index 09afe5d87f2b..4e8fe2c7b054 100644
--- a/tools/power/cpupower/utils/helpers/sysfs.c
+++ b/tools/power/cpupower/utils/helpers/sysfs.c
@@ -361,7 +361,7 @@ unsigned int sysfs_get_idlestate_count(unsigned int cpu)
 
         snprintf(file, SYSFS_PATH_MAX, PATH_TO_CPU "cpuidle");
         if (stat(file, &statbuf) != 0 || !S_ISDIR(statbuf.st_mode))
-                return -ENODEV;
+                return 0;
 
         snprintf(file, SYSFS_PATH_MAX, PATH_TO_CPU "cpu%u/cpuidle/state0", cpu);
         if (stat(file, &statbuf) != 0 || !S_ISDIR(statbuf.st_mode))