Update PM documentation

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3937 42af7a65-404d-4744-a932-0658087f49c3

4 files changed, 18 insertions, 12 deletions

diff --git a/nuttx/drivers/README.txt b/nuttx/drivers/README.txt
index 3c337956f..e5a1483b2 100644
--- a/nuttx/drivers/README.txt
+++ b/nuttx/drivers/README.txt
@@ -81,6 +81,12 @@ pipes/
 	FIFO and named pipe drivers.  Standard interfaces are declared
 	in include/unistd.h
 
+pm/
+    Power management (PM) driver interfaces.  These interfaces are used
+    to manage power usage of a platform by monitoring driver activity
+    and by placing drivers into reduce power usage modes when the
+    drivers are not active.
+
 sensors/
 	Drivers for various sensors
 
diff --git a/nuttx/drivers/pm/pm_activity.c b/nuttx/drivers/pm/pm_activity.c
index f1518520b..a0bae76fa 100644
--- a/nuttx/drivers/pm/pm_activity.c
+++ b/nuttx/drivers/pm/pm_activity.c
@@ -81,13 +81,13 @@
  * Description:
  *   This function is called by a device driver to indicate that it is
  *   performing meaningful activities (non-idle).  This increment an activty
- *   cound and/or will restart a idle timer and prevent entering IDLE
+ *   count and/or will restart a idle timer and prevent entering reduced
  *   power states.
  *
  * Input Parameters:
- *   priority - activity priority, range 0-9.  Larger values correspond to
+ *   priority - Activity priority, range 0-9.  Larger values correspond to
  *     higher priorities.  Higher priority activity can prevent the system
- *     fromentering reduced power states for a longer period of time.
+ *     from entering reduced power states for a longer period of time.
  *
  *     As an example, a button press might be higher priority activity because
  *     it means that the user is actively interacting with the device.
diff --git a/nuttx/drivers/pm/pm_changestate.c b/nuttx/drivers/pm/pm_changestate.c
index e98e46236..50fa0640f 100644
--- a/nuttx/drivers/pm/pm_changestate.c
+++ b/nuttx/drivers/pm/pm_changestate.c
@@ -77,7 +77,7 @@
  *   Prepare every driver for the state change.
  *
  * Input Parameters:
- *   newstate - Idenfifies the new PM state
+ *   newstate - Identifies the new PM state
  *
  * Returned Value:
  *   0 (OK) means that the callback function for all registered drivers
@@ -122,7 +122,7 @@ static int pm_prepall(enum pm_state_e newstate)
  *   Inform all drivers of the state change.
  *
  * Input Parameters:
- *   newstate - Idenfifies the new PM state
+ *   newstate - Identifies the new PM state
  *
  * Returned Value:
  *   None
@@ -147,7 +147,7 @@ static inline void pm_changeall(enum pm_state_e newstate)
         {
           /* Yes.. notify the driver */
 
-          (void)cb->notify(cb, newstate);
+          cb->notify(cb, newstate);
         }
     }
 }
@@ -160,12 +160,12 @@ static inline void pm_changeall(enum pm_state_e newstate)
  * Name: pm_changestate
  *
  * Description:
- *   This function is used to platform-specific power managmeent logic.  It
+ *   This function is used by platform-specific power management logic.  It
  *   will announce the power management power management state change to all
  *   drivers that have registered for power management event callbacks.
  *
  * Input Parameters:
- *   newstate - Idenfifies the new PM state
+ *   newstate - Identifies the new PM state
  *
  * Returned Value:
  *   0 (OK) means that the callback function for all registered drivers
diff --git a/nuttx/drivers/pm/pm_checkstate.c b/nuttx/drivers/pm/pm_checkstate.c
index 6b23ad05c..3a7f13d47 100644
--- a/nuttx/drivers/pm/pm_checkstate.c
+++ b/nuttx/drivers/pm/pm_checkstate.c
@@ -93,10 +93,10 @@
  *   even if there is activity.
  *
  *   NOTE: That these two steps are separated in time and, hence, the IDLE
- *   could be suspended for a long period of time between calling
- *   pm_checkstate() and pm_changestate().  There it is recommended that
- *   the IDLE loop make these calls atomic by either disabling interrupts
- *   until the state change is completed.
+ *   loop could be suspended for a long period of time between calling
+ *   pm_checkstate() and pm_changestate().  The IDLE loop may need to make
+ *   these calls atomic by either disabling interrupts until the state change
+ *   is completed.
  *
  * Input Parameters:
  *   None