1 files changed, 42 insertions, 13 deletions

diff --git a/drivers/cpuidle/governor.c b/drivers/cpuidle/governor.c
index 4e78263e34a4..5d0e7f78c6c5 100644
--- a/drivers/cpuidle/governor.c
+++ b/drivers/cpuidle/governor.c
@@ -8,21 +8,27 @@
  * This code is licenced under the GPL.
  */
 
-#include <linux/mutex.h>
+#include <linux/cpu.h>
 #include <linux/cpuidle.h>
+#include <linux/mutex.h>
+#include <linux/module.h>
+#include <linux/pm_qos.h>
 
 #include "cpuidle.h"
 
+char param_governor[CPUIDLE_NAME_LEN];
+
 LIST_HEAD(cpuidle_governors);
 struct cpuidle_governor *cpuidle_curr_governor;
+struct cpuidle_governor *cpuidle_prev_governor;
 
 /**
- * __cpuidle_find_governor - finds a governor of the specified name
+ * cpuidle_find_governor - finds a governor of the specified name
  * @str: the name
  *
  * Must be called with cpuidle_lock acquired.
  */
-static struct cpuidle_governor * __cpuidle_find_governor(const char *str)
+struct cpuidle_governor *cpuidle_find_governor(const char *str)
 {
 	struct cpuidle_governor *gov;
 
@@ -36,14 +42,15 @@ static struct cpuidle_governor * __cpuidle_find_governor(const char *str)
 /**
  * cpuidle_switch_governor - changes the governor
  * @gov: the new target governor
- *
- * NOTE: "gov" can be NULL to specify disabled
  * Must be called with cpuidle_lock acquired.
  */
 int cpuidle_switch_governor(struct cpuidle_governor *gov)
 {
 	struct cpuidle_device *dev;
 
+	if (!gov)
+		return -EINVAL;
+
 	if (gov == cpuidle_curr_governor)
 		return 0;
 
@@ -56,12 +63,11 @@ int cpuidle_switch_governor(struct cpuidle_governor *gov)
 
 	cpuidle_curr_governor = gov;
 
-	if (gov) {
-		list_for_each_entry(dev, &cpuidle_detected_devices, device_list)
-			cpuidle_enable_device(dev);
-		cpuidle_install_idle_handler();
-		printk(KERN_INFO "cpuidle: using governor %s\n", gov->name);
-	}
+	list_for_each_entry(dev, &cpuidle_detected_devices, device_list)
+		cpuidle_enable_device(dev);
+
+	cpuidle_install_idle_handler();
+	pr_info("cpuidle: using governor %s\n", gov->name);
 
 	return 0;
 }
@@ -81,14 +87,37 @@ int cpuidle_register_governor(struct cpuidle_governor *gov)
 		return -ENODEV;
 
 	mutex_lock(&cpuidle_lock);
-	if (__cpuidle_find_governor(gov->name) == NULL) {
+	if (cpuidle_find_governor(gov->name) == NULL) {
 		ret = 0;
 		list_add_tail(&gov->governor_list, &cpuidle_governors);
 		if (!cpuidle_curr_governor ||
-		    cpuidle_curr_governor->rating < gov->rating)
+		    !strncasecmp(param_governor, gov->name, CPUIDLE_NAME_LEN) ||
+		    (cpuidle_curr_governor->rating < gov->rating &&
+		     strncasecmp(param_governor, cpuidle_curr_governor->name,
+				 CPUIDLE_NAME_LEN)))
 			cpuidle_switch_governor(gov);
 	}
 	mutex_unlock(&cpuidle_lock);
 
 	return ret;
 }
+
+/**
+ * cpuidle_governor_latency_req - Compute a latency constraint for CPU
+ * @cpu: Target CPU
+ */
+s64 cpuidle_governor_latency_req(unsigned int cpu)
+{
+	struct device *device = get_cpu_device(cpu);
+	int device_req = dev_pm_qos_raw_resume_latency(device);
+	int global_req = cpu_latency_qos_limit();
+	int global_wake_req = cpu_wakeup_latency_qos_limit();
+
+	if (global_req > global_wake_req)
+		global_req = global_wake_req;
+
+	if (device_req > global_req)
+		device_req = global_req;
+
+	return (s64)device_req * NSEC_PER_USEC;
+}