PM / QoS: Prepare device structure for adding more constraint types

Currently struct dev_pm_info contains only one PM QoS constraints
pointer reserved for latency requirements.  Since one more device
constraints type (i.e. flags) will be necessary, introduce a new
structure, struct dev_pm_qos, that eventually will contain all of
the available device PM QoS constraints and replace the "constraints"
pointer in struct dev_pm_info with a pointer to the new structure
called "qos".

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Jean Pihet <j-pihet@ti.com>

diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c
index 74a67e0019a2d246820ccb2858399bca193ff789..40ff1b02a7c5c74282bdd1e0549a936023dbb521 100644 (file)
--- a/drivers/base/power/qos.c
+++ b/drivers/base/power/qos.c
@@ -55,9 +55,7 @@ static BLOCKING_NOTIFIER_HEAD(dev_pm_notifiers);
  */
 s32 __dev_pm_qos_read_value(struct device *dev)
 {
-       struct pm_qos_constraints *c = dev->power.constraints;
-
-       return c ? pm_qos_read_value(c) : 0;
+       return dev->power.qos ? pm_qos_read_value(&dev->power.qos->latency) : 0;
 }
 
 /**
@@ -91,12 +89,12 @@ static int apply_constraint(struct dev_pm_qos_request *req,
 {
        int ret, curr_value;
 
-       ret = pm_qos_update_target(req->dev->power.constraints,
+       ret = pm_qos_update_target(&req->dev->power.qos->latency,
                                   &req->node, action, value);
 
        if (ret) {
                /* Call the global callbacks if needed */
-               curr_value = pm_qos_read_value(req->dev->power.constraints);
+               curr_value = pm_qos_read_value(&req->dev->power.qos->latency);
                blocking_notifier_call_chain(&dev_pm_notifiers,
                                             (unsigned long)curr_value,
                                             req);
@@ -114,20 +112,22 @@ static int apply_constraint(struct dev_pm_qos_request *req,
  */
 static int dev_pm_qos_constraints_allocate(struct device *dev)
 {
+       struct dev_pm_qos *qos;
        struct pm_qos_constraints *c;
        struct blocking_notifier_head *n;
 
-       c = kzalloc(sizeof(*c), GFP_KERNEL);
-       if (!c)
+       qos = kzalloc(sizeof(*qos), GFP_KERNEL);
+       if (!qos)
                return -ENOMEM;
 
        n = kzalloc(sizeof(*n), GFP_KERNEL);
        if (!n) {
-               kfree(c);
+               kfree(qos);
                return -ENOMEM;
        }
        BLOCKING_INIT_NOTIFIER_HEAD(n);
 
+       c = &qos->latency;
        plist_head_init(&c->list);
        c->target_value = PM_QOS_DEV_LAT_DEFAULT_VALUE;
        c->default_value = PM_QOS_DEV_LAT_DEFAULT_VALUE;
@@ -135,7 +135,7 @@ static int dev_pm_qos_constraints_allocate(struct device *dev)
        c->notifiers = n;
 
        spin_lock_irq(&dev->power.lock);
-       dev->power.constraints = c;
+       dev->power.qos = qos;
        spin_unlock_irq(&dev->power.lock);
 
        return 0;
@@ -151,7 +151,7 @@ static int dev_pm_qos_constraints_allocate(struct device *dev)
 void dev_pm_qos_constraints_init(struct device *dev)
 {
        mutex_lock(&dev_pm_qos_mtx);
-       dev->power.constraints = NULL;
+       dev->power.qos = NULL;
        dev->power.power_state = PMSG_ON;
        mutex_unlock(&dev_pm_qos_mtx);
 }
@@ -164,6 +164,7 @@ void dev_pm_qos_constraints_init(struct device *dev)
  */
 void dev_pm_qos_constraints_destroy(struct device *dev)
 {
+       struct dev_pm_qos *qos;
        struct dev_pm_qos_request *req, *tmp;
        struct pm_qos_constraints *c;
 
@@ -176,10 +177,11 @@ void dev_pm_qos_constraints_destroy(struct device *dev)
        mutex_lock(&dev_pm_qos_mtx);
 
        dev->power.power_state = PMSG_INVALID;
-       c = dev->power.constraints;
-       if (!c)
+       qos = dev->power.qos;
+       if (!qos)
                goto out;
 
+       c = &qos->latency;
        /* Flush the constraints list for the device */
        plist_for_each_entry_safe(req, tmp, &c->list, node) {
                /*
@@ -191,7 +193,7 @@ void dev_pm_qos_constraints_destroy(struct device *dev)
        }
 
        spin_lock_irq(&dev->power.lock);
-       dev->power.constraints = NULL;
+       dev->power.qos = NULL;
        spin_unlock_irq(&dev->power.lock);
 
        kfree(c->notifiers);
@@ -235,7 +237,7 @@ int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req,
 
        mutex_lock(&dev_pm_qos_mtx);
 
-       if (!dev->power.constraints) {
+       if (!dev->power.qos) {
                if (dev->power.power_state.event == PM_EVENT_INVALID) {
                        /* The device has been removed from the system. */
                        req->dev = NULL;
@@ -290,7 +292,7 @@ int dev_pm_qos_update_request(struct dev_pm_qos_request *req,
 
        mutex_lock(&dev_pm_qos_mtx);
 
-       if (req->dev->power.constraints) {
+       if (req->dev->power.qos) {
                if (new_value != req->node.prio)
                        ret = apply_constraint(req, PM_QOS_UPDATE_REQ,
                                               new_value);
@@ -329,7 +331,7 @@ int dev_pm_qos_remove_request(struct dev_pm_qos_request *req)
 
        mutex_lock(&dev_pm_qos_mtx);
 
-       if (req->dev->power.constraints) {
+       if (req->dev->power.qos) {
                ret = apply_constraint(req, PM_QOS_REMOVE_REQ,
                                       PM_QOS_DEFAULT_VALUE);
                memset(req, 0, sizeof(*req));
@@ -362,13 +364,13 @@ int dev_pm_qos_add_notifier(struct device *dev, struct notifier_block *notifier)
 
        mutex_lock(&dev_pm_qos_mtx);
 
-       if (!dev->power.constraints)
+       if (!dev->power.qos)
                ret = dev->power.power_state.event != PM_EVENT_INVALID ?
                        dev_pm_qos_constraints_allocate(dev) : -ENODEV;
 
        if (!ret)
                ret = blocking_notifier_chain_register(
-                               dev->power.constraints->notifiers, notifier);
+                               dev->power.qos->latency.notifiers, notifier);
 
        mutex_unlock(&dev_pm_qos_mtx);
        return ret;
@@ -393,9 +395,9 @@ int dev_pm_qos_remove_notifier(struct device *dev,
        mutex_lock(&dev_pm_qos_mtx);
 
        /* Silently return if the constraints object is not present. */
-       if (dev->power.constraints)
+       if (dev->power.qos)
                retval = blocking_notifier_chain_unregister(
-                               dev->power.constraints->notifiers,
+                               dev->power.qos->latency.notifiers,
                                notifier);
 
        mutex_unlock(&dev_pm_qos_mtx);

diff --git a/include/linux/pm.h b/include/linux/pm.h
index 007e687c4f6915866b9d551bbc37cd14747f28ac..0ce6df94221ae611b40f376b4beb8ab2c8da2703 100644 (file)
--- a/include/linux/pm.h
+++ b/include/linux/pm.h
@@ -549,7 +549,7 @@ struct dev_pm_info {
        struct dev_pm_qos_request *pq_req;
 #endif
        struct pm_subsys_data   *subsys_data;  /* Owned by the subsystem. */
-       struct pm_qos_constraints *constraints;
+       struct dev_pm_qos       *qos;
 };
 
 extern void update_pm_runtime_accounting(struct device *dev);

diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
index 9924ea1f22e07306f39607e08df8b36244832ab9..30e9ad72e79742504f85c0cb3f60b4e6fd95fd53 100644 (file)
--- a/include/linux/pm_qos.h
+++ b/include/linux/pm_qos.h
@@ -57,6 +57,10 @@ struct pm_qos_constraints {
        struct blocking_notifier_head *notifiers;
 };
 
+struct dev_pm_qos {
+       struct pm_qos_constraints latency;
+};
+
 /* Action requested to pm_qos_update_target */
 enum pm_qos_req_action {
        PM_QOS_ADD_REQ,         /* Add a new request */