diff mbox

[V3,3/4] cpuidle: prepare the driver core to be multi drivers aware

Message ID 1351701888-19963-4-git-send-email-daniel.lezcano@linaro.org
State Accepted
Commit 13dd52f11a04e616900f565d6a1e5138e58d579f
Headers show

Commit Message

Daniel Lezcano Oct. 31, 2012, 4:44 p.m. UTC 
This patch is a preparation for the multiple drivers support.

As the next patch will introduce the multiple drivers with the Kconfig
option and we want to keep the code clean and understandable, this patch
defines a set of functions for encapsulating some common parts and split
what should be done in a lock context or not.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
---
 drivers/cpuidle/driver.c |   60 ++++++++++++++++++++++++++++++++-------------
 1 files changed, 42 insertions(+), 18 deletions(-)
diff mbox

Patch

diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c
index 3e59075..8246662 100644
--- a/drivers/cpuidle/driver.c
+++ b/drivers/cpuidle/driver.c
@@ -39,11 +39,20 @@  static void set_power_states(struct cpuidle_driver *drv)
 		drv->states[i].power_usage = -1 - i;
 }
 
-/**
- * cpuidle_register_driver - registers a driver
- * @drv: the driver
- */
-int cpuidle_register_driver(struct cpuidle_driver *drv)
+static void __cpuidle_driver_init(struct cpuidle_driver *drv)
+{
+	drv->refcnt = 0;
+
+	if (!drv->power_specified)
+		set_power_states(drv);
+}
+
+static void cpuidle_set_driver(struct cpuidle_driver *drv)
+{
+	cpuidle_curr_driver = drv;
+}
+
+static int __cpuidle_register_driver(struct cpuidle_driver *drv)
 {
 	if (!drv || !drv->state_count)
 		return -EINVAL;
@@ -51,22 +60,38 @@  int cpuidle_register_driver(struct cpuidle_driver *drv)
 	if (cpuidle_disabled())
 		return -ENODEV;
 
-	spin_lock(&cpuidle_driver_lock);
-	if (cpuidle_curr_driver) {
-		spin_unlock(&cpuidle_driver_lock);
+	if (cpuidle_get_driver())
 		return -EBUSY;
-	}
 
-	if (!drv->power_specified)
-		set_power_states(drv);
+	__cpuidle_driver_init(drv);
 
-	drv->refcnt = 0;
+	cpuidle_set_driver(drv);
 
-	cpuidle_curr_driver = drv;
+	return 0;
+}
+
+static void __cpuidle_unregister_driver(struct cpuidle_driver *drv)
+{
+	if (drv != cpuidle_get_driver())
+		return;
+
+	if (!WARN_ON(drv->refcnt > 0))
+		cpuidle_set_driver(NULL);
+}
 
+/**
+ * cpuidle_register_driver - registers a driver
+ * @drv: the driver
+ */
+int cpuidle_register_driver(struct cpuidle_driver *drv)
+{
+	int ret;
+
+	spin_lock(&cpuidle_driver_lock);
+	ret = __cpuidle_register_driver(drv);
 	spin_unlock(&cpuidle_driver_lock);
 
-	return 0;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(cpuidle_register_driver);
 
@@ -86,8 +111,7 @@  EXPORT_SYMBOL_GPL(cpuidle_get_driver);
 void cpuidle_unregister_driver(struct cpuidle_driver *drv)
 {
 	spin_lock(&cpuidle_driver_lock);
-	if (drv == cpuidle_curr_driver && !WARN_ON(drv->refcnt > 0))
-		cpuidle_curr_driver = NULL;
+	__cpuidle_unregister_driver(drv);
 	spin_unlock(&cpuidle_driver_lock);
 }
 EXPORT_SYMBOL_GPL(cpuidle_unregister_driver);
@@ -98,7 +122,7 @@  struct cpuidle_driver *cpuidle_driver_ref(void)
 
 	spin_lock(&cpuidle_driver_lock);
 
-	drv = cpuidle_curr_driver;
+	drv = cpuidle_get_driver();
 	drv->refcnt++;
 
 	spin_unlock(&cpuidle_driver_lock);
@@ -107,7 +131,7 @@  struct cpuidle_driver *cpuidle_driver_ref(void)
 
 void cpuidle_driver_unref(void)
 {
-	struct cpuidle_driver *drv = cpuidle_curr_driver;
+	struct cpuidle_driver *drv = cpuidle_get_driver();
 
 	spin_lock(&cpuidle_driver_lock);