summaryrefslogtreecommitdiffstats
path: root/kernel/power
diff options
context:
space:
mode:
authorRafael J. Wysocki <rafael.j.wysocki@intel.com>2012-10-23 01:07:46 +0200
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2012-10-23 01:07:46 +0200
commit5efbe4279f959a3f5ed26adf5f05cb78dd1ffa7e (patch)
treeebc9bc44e7ac33b11c187850291114f30c39455a /kernel/power
parent5f986c590fcf4284924fcda991cf14ab32bff49f (diff)
downloadlinux-stable-5efbe4279f959a3f5ed26adf5f05cb78dd1ffa7e.tar.gz
linux-stable-5efbe4279f959a3f5ed26adf5f05cb78dd1ffa7e.tar.bz2
linux-stable-5efbe4279f959a3f5ed26adf5f05cb78dd1ffa7e.zip
PM / QoS: Introduce request and constraint data types for PM QoS flags
Introduce struct pm_qos_flags_request and struct pm_qos_flags representing PM QoS flags request type and PM QoS flags constraint type, respectively. With these definitions the data structures will be arranged so that the list member of a struct pm_qos_flags object will contain the head of a list of struct pm_qos_flags_request objects representing all of the "flags" requests present for the given device. Then, the effective_flags member of a struct pm_qos_flags object will contain the bitwise OR of the flags members of all the struct pm_qos_flags_request objects in the list. Additionally, introduce helper function pm_qos_update_flags() allowing the caller to manage the list of struct pm_qos_flags_request pointed to by the list member of struct pm_qos_flags. The flags are of type s32 so that the request's "value" field is always of the same type regardless of what kind of request it is (latency requests already have value fields of type s32). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Jean Pihet <j-pihet@ti.com> Acked-by: mark gross <markgross@thegnar.org>
Diffstat (limited to 'kernel/power')
-rw-r--r--kernel/power/qos.c63
1 files changed, 63 insertions, 0 deletions
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index 846bd42c7ed1..2ab2819aee65 100644
--- a/kernel/power/qos.c
+++ b/kernel/power/qos.c
@@ -213,6 +213,69 @@ int pm_qos_update_target(struct pm_qos_constraints *c, struct plist_node *node,
}
/**
+ * pm_qos_flags_remove_req - Remove device PM QoS flags request.
+ * @pqf: Device PM QoS flags set to remove the request from.
+ * @req: Request to remove from the set.
+ */
+static void pm_qos_flags_remove_req(struct pm_qos_flags *pqf,
+ struct pm_qos_flags_request *req)
+{
+ s32 val = 0;
+
+ list_del(&req->node);
+ list_for_each_entry(req, &pqf->list, node)
+ val |= req->flags;
+
+ pqf->effective_flags = val;
+}
+
+/**
+ * pm_qos_update_flags - Update a set of PM QoS flags.
+ * @pqf: Set of flags to update.
+ * @req: Request to add to the set, to modify, or to remove from the set.
+ * @action: Action to take on the set.
+ * @val: Value of the request to add or modify.
+ *
+ * Update the given set of PM QoS flags and call notifiers if the aggregate
+ * value has changed. Returns 1 if the aggregate constraint value has changed,
+ * 0 otherwise.
+ */
+bool pm_qos_update_flags(struct pm_qos_flags *pqf,
+ struct pm_qos_flags_request *req,
+ enum pm_qos_req_action action, s32 val)
+{
+ unsigned long irqflags;
+ s32 prev_value, curr_value;
+
+ spin_lock_irqsave(&pm_qos_lock, irqflags);
+
+ prev_value = list_empty(&pqf->list) ? 0 : pqf->effective_flags;
+
+ switch (action) {
+ case PM_QOS_REMOVE_REQ:
+ pm_qos_flags_remove_req(pqf, req);
+ break;
+ case PM_QOS_UPDATE_REQ:
+ pm_qos_flags_remove_req(pqf, req);
+ case PM_QOS_ADD_REQ:
+ req->flags = val;
+ INIT_LIST_HEAD(&req->node);
+ list_add_tail(&req->node, &pqf->list);
+ pqf->effective_flags |= val;
+ break;
+ default:
+ /* no action */
+ ;
+ }
+
+ curr_value = list_empty(&pqf->list) ? 0 : pqf->effective_flags;
+
+ spin_unlock_irqrestore(&pm_qos_lock, irqflags);
+
+ return prev_value != curr_value;
+}
+
+/**
* pm_qos_request - returns current system wide qos expectation
* @pm_qos_class: identification of which qos value is requested
*