Merge branch 'pm-qos'

* pm-qos: (30 commits)
  PM: QoS: annotate data races in pm_qos_*_value()
  Documentation: power: fix pm_qos_interface.rst format warning
  PM: QoS: Make CPU latency QoS depend on CONFIG_CPU_IDLE
  Documentation: PM: QoS: Update to reflect previous code changes
  PM: QoS: Update file information comments
  PM: QoS: Drop PM_QOS_CPU_DMA_LATENCY and rename related functions
  sound: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: usb: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: tty: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: spi: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: net: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: mmc: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: media: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: hsi: Call cpu_latency_qos_*() instead of pm_qos_*()
  drm: i915: Call cpu_latency_qos_*() instead of pm_qos_*()
  x86: platform: iosf_mbi: Call cpu_latency_qos_*() instead of pm_qos_*()
  cpuidle: Call cpu_latency_qos_limit() instead of pm_qos_request()
  PM: QoS: Add CPU latency QoS API wrappers
  PM: QoS: Adjust pm_qos_request() signature and reorder pm_qos.h
  PM: QoS: Simplify definitions of CPU latency QoS trace events
  ...

1 files changed, 40 insertions, 48 deletions

diff --git a/Documentation/power/pm_qos_interface.rst b/Documentation/power/pm_qos_interface.rst
index 0d62d506caf0..69b0fe3e2542 100644
--- a/Documentation/power/pm_qos_interface.rst
+++ b/Documentation/power/pm_qos_interface.rst
@@ -7,86 +7,78 @@ 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
-2. The per-device PM QoS framework provides the API to manage the
+ * CPU latency QoS.
+ * The per-device PM QoS framework provides the API to manage the
    per-device latency constraints and PM QoS flags.
 
-Each parameters have defined units:
-
- * latency: usec
- * timeout: usec
- * throughput: kbs (kilo bit / sec)
- * memory bandwidth: mbs (mega bit / sec)
+The latency unit used in the PM QoS framework is the microsecond (usec).
 
 
 1. PM QoS framework
 ===================
 
-The infrastructure exposes multiple misc device nodes one per implemented
-parameter.  The set of parameters implement is defined by pm_qos_power_init()
-and pm_qos_params.h.  This is done because having the available parameters
-being runtime configurable or changeable from a driver was seen as too easy to
-abuse.
-
-For each parameter a list of performance requests is maintained along with
-an aggregated target value.  The aggregated target value is updated with
-changes to the request list or elements of the list.  Typically the
-aggregated target value is simply the max or min of the request values held
-in the parameter list elements.
+A global list of CPU latency QoS requests is maintained along with an aggregated
+(effective) target value.  The aggregated target value is updated with changes
+to the request list or elements of the list.  For CPU latency QoS, the
+aggregated target value is simply the min of the request values held in the list
+elements.
+
 Note: the aggregated target value is implemented as an atomic variable so that
 reading the aggregated value does not require any locking mechanism.
 
+From kernel space the use of this interface is simple:
 
-From kernel mode the use of this interface is simple:
-
-void pm_qos_add_request(handle, param_class, target_value):
-  Will insert an element into the list for that identified PM QoS class with the
-  target value.  Upon change to this list the new target is recomputed and any
-  registered notifiers are called only if the target value is now different.
-  Clients of pm_qos need to save the returned handle for future use in other
-  pm_qos API functions.
+void cpu_latency_qos_add_request(handle, target_value):
+  Will insert an element into the CPU latency QoS list with the target value.
+  Upon change to this list the new target is recomputed and any registered
+  notifiers are called only if the target value is now different.
+  Clients of PM QoS need to save the returned handle for future use in other
+  PM QoS API functions.
 
-void pm_qos_update_request(handle, new_target_value):
+void cpu_latency_qos_update_request(handle, new_target_value):
   Will update the list element pointed to by the handle with the new target
   value and recompute the new aggregated target, calling the notification tree
   if the target is changed.
 
-void pm_qos_remove_request(handle):
+void cpu_latency_qos_remove_request(handle):
   Will remove the element.  After removal it will update the aggregate target
   and call the notification tree if the target was changed as a result of
   removing the request.
 
-int pm_qos_request(param_class):
-  Returns the aggregated value for a given PM QoS class.
+int cpu_latency_qos_limit():
+  Returns the aggregated value for the CPU latency QoS.
+
+int cpu_latency_qos_request_active(handle):
+  Returns if the request is still active, i.e. it has not been removed from the
+  CPU latency QoS list.
 
-int pm_qos_request_active(handle):
-  Returns if the request is still active, i.e. it has not been removed from a
-  PM QoS class constraints list.
+int cpu_latency_qos_add_notifier(notifier):
+  Adds a notification callback function to the CPU latency QoS. The callback is
+  called when the aggregated value for the CPU latency QoS is changed.
 
-int pm_qos_add_notifier(param_class, notifier):
-  Adds a notification callback function to the PM QoS class. The callback is
-  called when the aggregated value for the PM QoS class is changed.
+int cpu_latency_qos_remove_notifier(notifier):
+  Removes the notification callback function from the CPU latency QoS.
 
-int pm_qos_remove_notifier(int param_class, notifier):
-  Removes the notification callback function for the PM QoS class.
 
+From user space:
 
-From user mode:
+The infrastructure exposes one device node, /dev/cpu_dma_latency, for the CPU
+latency QoS.
 
-Only processes can register a pm_qos request.  To provide for automatic
+Only processes can register a PM QoS request.  To provide for automatic
 cleanup of a process, the interface requires the process to register its
-parameter requests in the following way:
+parameter requests as follows.
 
-To register the default pm_qos target for the specific parameter, the process
-must open /dev/cpu_dma_latency
+To register the default PM QoS target for the CPU latency QoS, the process must
+open /dev/cpu_dma_latency.
 
 As long as the device node is held open that process has a registered
 request on the parameter.
 
-To change the requested target value the process needs to write an s32 value to
-the open device node.  Alternatively the user mode program could write a hex
-string for the value using 10 char long format e.g. "0x12345678".  This
-translates to a pm_qos_update_request call.
+To change the requested target value, the process needs to write an s32 value to
+the open device node.  Alternatively, it can write a hex string for the value
+using the 10 char long format e.g. "0x12345678".  This translates to a
+cpu_latency_qos_update_request() call.
 
 To remove the user mode request for a target value simply close the device
 node.