1 files changed, 19 insertions, 27 deletions

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index ee61db93163c..73ccddf94cf4 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -349,7 +349,7 @@ static struct pstate_adjust_policy pid_params __read_mostly = {
 static int hwp_active __read_mostly;
 static bool per_cpu_limits __read_mostly;
 
-static bool driver_registered __read_mostly;
+static struct cpufreq_driver *intel_pstate_driver __read_mostly;
 
 #ifdef CONFIG_ACPI
 static bool acpi_ppc;
@@ -1035,7 +1035,7 @@ static ssize_t show_turbo_pct(struct kobject *kobj,
 
         mutex_lock(&intel_pstate_driver_lock);
 
-        if (!driver_registered) {
+        if (!intel_pstate_driver) {
                 mutex_unlock(&intel_pstate_driver_lock);
                 return -EAGAIN;
         }
@@ -1060,7 +1060,7 @@ static ssize_t show_num_pstates(struct kobject *kobj,
 
         mutex_lock(&intel_pstate_driver_lock);
 
-        if (!driver_registered) {
+        if (!intel_pstate_driver) {
                 mutex_unlock(&intel_pstate_driver_lock);
                 return -EAGAIN;
         }
@@ -1080,7 +1080,7 @@ static ssize_t show_no_turbo(struct kobject *kobj,
 
         mutex_lock(&intel_pstate_driver_lock);
 
-        if (!driver_registered) {
+        if (!intel_pstate_driver) {
                 mutex_unlock(&intel_pstate_driver_lock);
                 return -EAGAIN;
         }
@@ -1108,7 +1108,7 @@ static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
 
         mutex_lock(&intel_pstate_driver_lock);
 
-        if (!driver_registered) {
+        if (!intel_pstate_driver) {
                 mutex_unlock(&intel_pstate_driver_lock);
                 return -EAGAIN;
         }
@@ -1155,7 +1155,7 @@ static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
 
         mutex_lock(&intel_pstate_driver_lock);
 
-        if (!driver_registered) {
+        if (!intel_pstate_driver) {
                 mutex_unlock(&intel_pstate_driver_lock);
                 return -EAGAIN;
         }
@@ -1185,7 +1185,7 @@ static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
 
         mutex_lock(&intel_pstate_driver_lock);
 
-        if (!driver_registered) {
+        if (!intel_pstate_driver) {
                 mutex_unlock(&intel_pstate_driver_lock);
                 return -EAGAIN;
         }
@@ -2255,7 +2255,7 @@ static struct cpufreq_driver intel_cpufreq = {
         .name           = "intel_cpufreq",
 };
 
-static struct cpufreq_driver *intel_pstate_driver = &intel_pstate;
+static struct cpufreq_driver *default_driver = &intel_pstate;
 
 static void intel_pstate_driver_cleanup(void)
 {
@@ -2272,15 +2272,17 @@ static void intel_pstate_driver_cleanup(void)
                 }
         }
         put_online_cpus();
+        intel_pstate_driver = NULL;
 }
 
-static int intel_pstate_register_driver(void)
+static int intel_pstate_register_driver(struct cpufreq_driver *driver)
 {
         int ret;
 
         memset(&global, 0, sizeof(global));
         global.max_perf_pct = 100;
 
+        intel_pstate_driver = driver;
         ret = cpufreq_register_driver(intel_pstate_driver);
         if (ret) {
                 intel_pstate_driver_cleanup();
@@ -2289,10 +2291,6 @@ static int intel_pstate_register_driver(void)
 
         global.min_perf_pct = min_perf_pct_min();
 
-        mutex_lock(&intel_pstate_limits_lock);
-        driver_registered = true;
-        mutex_unlock(&intel_pstate_limits_lock);
-
         if (intel_pstate_driver == &intel_pstate && !hwp_active &&
             pstate_funcs.get_target_pstate != get_target_pstate_use_cpu_load)
                 intel_pstate_debug_expose_params();
@@ -2309,10 +2307,6 @@ static int intel_pstate_unregister_driver(void)
             pstate_funcs.get_target_pstate != get_target_pstate_use_cpu_load)
                 intel_pstate_debug_hide_params();
 
-        mutex_lock(&intel_pstate_limits_lock);
-        driver_registered = false;
-        mutex_unlock(&intel_pstate_limits_lock);
-
         cpufreq_unregister_driver(intel_pstate_driver);
         intel_pstate_driver_cleanup();
 
@@ -2321,7 +2315,7 @@ static int intel_pstate_unregister_driver(void)
 
 static ssize_t intel_pstate_show_status(char *buf)
 {
-        if (!driver_registered)
+        if (!intel_pstate_driver)
                 return sprintf(buf, "off\n");
 
         return sprintf(buf, "%s\n", intel_pstate_driver == &intel_pstate ?
@@ -2333,11 +2327,11 @@ static int intel_pstate_update_status(const char *buf, size_t size)
         int ret;
 
         if (size == 3 && !strncmp(buf, "off", size))
-                return driver_registered ?
+                return intel_pstate_driver ?
                         intel_pstate_unregister_driver() : -EINVAL;
 
         if (size == 6 && !strncmp(buf, "active", size)) {
-                if (driver_registered) {
+                if (intel_pstate_driver) {
                         if (intel_pstate_driver == &intel_pstate)
                                 return 0;
 
@@ -2346,12 +2340,11 @@ static int intel_pstate_update_status(const char *buf, size_t size)
                                 return ret;
                 }
 
-                intel_pstate_driver = &intel_pstate;
-                return intel_pstate_register_driver();
+                return intel_pstate_register_driver(&intel_pstate);
         }
 
         if (size == 7 && !strncmp(buf, "passive", size)) {
-                if (driver_registered) {
+                if (intel_pstate_driver) {
                         if (intel_pstate_driver != &intel_pstate)
                                 return 0;
 
@@ -2360,8 +2353,7 @@ static int intel_pstate_update_status(const char *buf, size_t size)
                                 return ret;
                 }
 
-                intel_pstate_driver = &intel_cpufreq;
-                return intel_pstate_register_driver();
+                return intel_pstate_register_driver(&intel_cpufreq);
         }
 
         return -EINVAL;
@@ -2601,7 +2593,7 @@ hwp_cpu_matched:
         intel_pstate_sysfs_expose_params();
 
         mutex_lock(&intel_pstate_driver_lock);
-        rc = intel_pstate_register_driver();
+        rc = intel_pstate_register_driver(default_driver);
         mutex_unlock(&intel_pstate_driver_lock);
         if (rc)
                 return rc;
@@ -2622,7 +2614,7 @@ static int __init intel_pstate_setup(char *str)
                 no_load = 1;
         } else if (!strcmp(str, "passive")) {
                 pr_info("Passive mode enabled\n");
-                intel_pstate_driver = &intel_cpufreq;
+                default_driver = &intel_cpufreq;
                 no_hwp = 1;
         }
         if (!strcmp(str, "no_hwp")) {