3 files changed, 33 insertions, 3 deletions

diff --git a/Documentation/power/pm_qos_interface.txt b/Documentation/power/pm_qos_interface.txt
index a5da5c7e7128..129f7c0e1483 100644
--- a/Documentation/power/pm_qos_interface.txt
+++ b/Documentation/power/pm_qos_interface.txt
@@ -5,7 +5,8 @@ performance expectations by drivers, subsystems and user space applications on
 one of the parameters.
 
 Two different PM QoS frameworks are available:
-1. PM QoS classes for cpu_dma_latency, network_latency, network_throughput.
+1. PM QoS classes for cpu_dma_latency, network_latency, network_throughput,
+memory_bandwidth.
 2. the per-device PM QoS framework provides the API to manage the per-device latency
 constraints and PM QoS flags.
 
@@ -13,6 +14,7 @@ Each parameters have defined units:
  * latency: usec
  * timeout: usec
  * throughput: kbs (kilo bit / sec)
+ * memory bandwidth: mbs (mega bit / sec)
 
 
 1. PM QoS framework
diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
index 9ab4bf7c4646..636e82834506 100644
--- a/include/linux/pm_qos.h
+++ b/include/linux/pm_qos.h
@@ -15,6 +15,7 @@ enum {
         PM_QOS_CPU_DMA_LATENCY,
         PM_QOS_NETWORK_LATENCY,
         PM_QOS_NETWORK_THROUGHPUT,
+        PM_QOS_MEMORY_BANDWIDTH,
 
         /* insert new class ID */
         PM_QOS_NUM_CLASSES,
@@ -32,6 +33,7 @@ enum pm_qos_flags_status {
 #define PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE        (2000 * USEC_PER_SEC)
 #define PM_QOS_NETWORK_LAT_DEFAULT_VALUE        (2000 * USEC_PER_SEC)
 #define PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE 0
+#define PM_QOS_MEMORY_BANDWIDTH_DEFAULT_VALUE   0
 #define PM_QOS_RESUME_LATENCY_DEFAULT_VALUE     0
 #define PM_QOS_LATENCY_TOLERANCE_DEFAULT_VALUE  0
 #define PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT  (-1)
@@ -69,7 +71,8 @@ struct dev_pm_qos_request {
 enum pm_qos_type {
         PM_QOS_UNITIALIZED,
         PM_QOS_MAX,             /* return the largest value */
-        PM_QOS_MIN              /* return the smallest value */
+        PM_QOS_MIN,             /* return the smallest value */
+        PM_QOS_SUM              /* return the sum */
 };
 
 /*
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index 884b77058864..5f4c006c4b1e 100644
--- a/kernel/power/qos.c
+++ b/kernel/power/qos.c
@@ -105,11 +105,27 @@ static struct pm_qos_object network_throughput_pm_qos = {
 };
 
 
+static BLOCKING_NOTIFIER_HEAD(memory_bandwidth_notifier);
+static struct pm_qos_constraints memory_bw_constraints = {
+        .list = PLIST_HEAD_INIT(memory_bw_constraints.list),
+        .target_value = PM_QOS_MEMORY_BANDWIDTH_DEFAULT_VALUE,
+        .default_value = PM_QOS_MEMORY_BANDWIDTH_DEFAULT_VALUE,
+        .no_constraint_value = PM_QOS_MEMORY_BANDWIDTH_DEFAULT_VALUE,
+        .type = PM_QOS_SUM,
+        .notifiers = &memory_bandwidth_notifier,
+};
+static struct pm_qos_object memory_bandwidth_pm_qos = {
+        .constraints = &memory_bw_constraints,
+        .name = "memory_bandwidth",
+};
+
+
 static struct pm_qos_object *pm_qos_array[] = {
         &null_pm_qos,
         &cpu_dma_pm_qos,
         &network_lat_pm_qos,
-        &network_throughput_pm_qos
+        &network_throughput_pm_qos,
+        &memory_bandwidth_pm_qos,
 };
 
 static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf,
@@ -130,6 +146,9 @@ static const struct file_operations pm_qos_power_fops = {
 /* unlocked internal variant */
 static inline int pm_qos_get_value(struct pm_qos_constraints *c)
 {
+        struct plist_node *node;
+        int total_value = 0;
+
         if (plist_head_empty(&c->list))
                 return c->no_constraint_value;
 
@@ -140,6 +159,12 @@ static inline int pm_qos_get_value(struct pm_qos_constraints *c)
         case PM_QOS_MAX:
                 return plist_last(&c->list)->prio;
 
+        case PM_QOS_SUM:
+                plist_for_each(node, &c->list)
+                        total_value += node->prio;
+
+                return total_value;
+
         default:
                 /* runtime check for not using enum */
                 BUG();